A small species of Ambystoma, dark gray to black with a yellow, tan or olive green dorsal stripe often broken up into blotches (Stebbins 1951). The sides have some white speckling. The ventral side is gray or black (Petranka 1998).
Ambystoma macrodactylum columbianum A. m. croceum, A. m. krausei, A. m. macrodactylum, A. m. sigillatum are subspecies.
occurs (regularly, as a native taxon) in multiple nations
Global Range: (20,000-2,500,000 square km (about 8000-1,000,000 square miles)) Range extends from southeastern Alaska southward to Tuolumne County, California, east to Rocky Mountains (east to east-central British Columbia, west-central Alberta, western Montana, and central Idaho). Isolated populations exist in Santa Cruz and Monterey counties, California (Bury et al. 1980). Elevational range extends from sea level to about 10,000 feet (Stebbins 1985).
Regional Distribution in the Western United States
This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):
1 Northern Pacific Border
2 Cascade Mountains
3 Southern Pacific Border
4 Sierra Mountains
5 Columbia Plateau
8 Northern Rocky Mountains
Occurrence in North America
western long-toed salamander: Vancouver Island, British Columbia; Coastal Ranges of Washington and Oregon
eastern long-toed salamander: southeastern Alaska and northern British Columbia; central and eastern Washington; north-central and northeastern Oregon; western half of the Idaho panhandle
northern long-toed salamander: eastern British Columbia; extreme western Alberta; western Montana; eastern half of the Idaho panhandle
southern long-toed salamander: southwestern Oregon; northeastern California
Santa Cruz long-toed salamander: a disjunct population known from only 3 locations in California - Ellicott Pond State Wildlife Reserve, Santa Cruz Co.; Valencia Lagoon, Santa Cruz Co.; Elkhorn Slough, Monterey Co.
Distribution and Habitat
Their range extends from south-eastern Alaska south to northern California, and from the Pacific coast east to north-central Idaho and western Montana (Petranka 1998). Found in a variety of habitats from coniferous forests to sagebrush plains to alpine meadows. Found on the ground under bark, rocks, and rotting wood piles. Also found in the quiet water of streams, ponds and lakes (Stebbins 1951).
Length: 17 cm
Catalog Number: USNM 48598
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Amphibians & Reptiles
Year Collected: 1906
Locality: Bloomfield, Davis, Iowa, United States, North America
Catalog Number: USNM 48599
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Amphibians & Reptiles
Year Collected: 1906
Locality: Bloomfield, Davis, Iowa, United States, North America
Catalog Number: USNM 4042
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Amphibians & Reptiles
Locality: Astoria, Clatsop, Oregon, United States, North America
Central and Southern Cascades Forests Habitat
The Oregon slender salamander is endemic to the Central and Southern Cascades forests ecoregion. The Central and Southern Cascades forests span several physiographic provinces in Washington and Oregon, including the southern Cascades, the Western Cascades, and the High Cascades, all within the USA. This ecoregion extends from Snoqualmie Pass in Washington to slightly north of the California border. The region is characterized by accordant ridge crests separated by steep, deeply dissected valleys, strongly influenced by historic and recent volcanic events (e.g. Mount Saint Helens).
This ecoregion contains one of the highest levels of endemic amphibians (five of eleven ecoregion endemics are amphibians) of any ecoregion within its major habitat type. The threatened Northern spotted owl has been used as an indicator species in environmental impact assessments, since its range overlaps with 39 listed or proposed species (ten of which are late-seral associates) and 1116 total species associated with late-seral forests. Late-seral forests in general are of national and global importance because they provide some of the last refugia for dependent species, and perform vital ecological services, including sequestration of carbon, cleansing of atmospheric pollutants, and maintenance of hydrological regimes.
There are a number ofl amphibian taxa present in the Central and Southern Cascades ecoregion; the totality of these amphibian taxa are: the Rough-skinned newt (Taricha granulosa); the endemic and Vulnerable Shasta salamander (Hydromantes shastae); the endemic and Vulnerable Oregon slender salamander (Batrachoseps wrighti); the Endangered Dunn's salamander (Bolitoglossa dunni); the Northwestern salamander (Ambystoma gracile); the Near Threatened western toad (Anaxyrus boreas); the Vulnerable Oregon spotted frog (Rana pretiosa); the Near Threatened Cascades frog (Rana cascadae); Coastal tailed frog (Ascaphus truei); Near Threatened Larch Mountain salamander (Plethodon larselli); California newt (Taricha torosa); Pacific giant salamander (Dicamptodon ensatus); Cope's giant salamander (Dicamptodon copei); Monterey ensatina (Ensatina eschscholtzii); the Near Threatened Foothill yellow-legged frog (Rana boylii); Northern Red-legged frog (Rana aurora); Pacific chorus frog (Pseudacris regilla); Van Dyke's salamander (Plethodon vandykei), an endemic of the State of Washington, USA; Long-toed salamander (Ambystoma macrodactylum); and the Olympic torrent salamander (Rhyacotriton olympicus).
There are a moderate number of reptilian species present in the ecoregion, namely in total they are: Western pond turtle (Emys marmorata); Western fence lizard (Sceloporus occidentalis); Sharp-tailed snake (Contia tenuis); Ringed-neck snake (Diadophis punctatus); Rubber boa (Charina bottae); California mountain kingsnake (Lampropeltis zonata); Yellow-bellied racer (Coluber constrictor); Western rattlesnake (Crotalus viridis); Western gopher snake (Pituophis catenifer); Common garter snake (Thanophis sirtalis); Northwestern garter snake (Thamnophis ordinoides); Western skink (Megascops kennicottii); Southern alligator lizard (Elgaria multicarinata); and the Northern alligator lizard (Elgaria coerulea).
There is a considerable number of avifauna within the Central and Southern Cascades ecoregion; representative species being: Flammulated owl (Otus flammeolus); Western screech owl (Megascops kennicottii); White-tailed ptarmigan (Picoides albolarvatus); and White-headed woodpecker (Picoides albolarvatus).
There are a large number of mammalian taxa in the ecoregion, including: Bobcat (Lynx rufus); Wolverine (Gulo gulo); California ground squirrel (Spermophilus beecheyi); Yellow-bellied marmot (Marmota flaviventris); Ermine (Mustela erminea); Fog shrew (Sorex sonomae), an endemic mammal to the far western USA; Hoary marmot (Marmota caligata); Mountain beaver (Aplodontia rufa); and the Near Threatened red tree vole (Arborimus longicaudus); Yellow pine chipmunk (Tamias amoenus); and the American water shrew (Sorex palustris).
Puget Lowland Forests Habitat
Cope's giant salamander is found in the Puget lowland forests along with several other western North America ecoregions. The Puget lowland forests occupy a north-south topographic depression between the Olympic Peninsula and western slopes of the Cascade Mountains, extending from north of the Canadian border to the lower Columbia River along the Oregon border. The portion of this forest ecoregion within British Columbia includes the Fraser Valley lowlands, the coastal lowlands locally known as the Sunshine Coast and several of the Gulf Islands. This ecoregion is within the Nearctic Realm and classified as part of the Temperate Coniferous Forests biome.
The Puget lowland forests have a Mediterranean-like climate, with warm, dry summers, and mild wet winters. The mean annual temperature is 9°C, the mean summer temperature is 15°C, and the mean winter temperature is 3.5°C. Annual precipitation averages 800 to 900 millimeters (mm) but may be as great as 1530 mm. Only a small percentage of this precipitation falls as snow. However, annual rainfall on the San Juan Islands can be as low as 460 mm, due to rain-shadow effects caused by the Olympic Mountains. This local rain shadow effect results in some of the driest sites encountered in the region. Varied topography on these hilly islands results in a diverse assemblage of plant communities arranged along orographically defiined moisture gradients. Open grasslands with widely scattered trees dominate the exposed southern aspects of the islands, while moister dense forests occur on northern sheltered slopes characterized by Western red cedar (Thuja plicata), Grand fir (Abies grandis), and Sword fern (Polystichum munitum) communities.
There are only a small number of amphibian taxa in the Puget lowland forests, namely: Cope's giant salamander (Dicamptodon copei); Monterey ensatina (Ensatina eschscholtzii); Long-toed salamander (Ambystoma macrodactylum); Western redback salamander (Plethodon vehiculum); Northwestern salamander (Ambystoma gracile); Pacific chorus frog (Pseudacris regilla); Coastal giant salamander (Dicamptodon tenebrosus); Rough-skin newt (Taricha granulosa); the Vulnerable Spotted frog (Rana pretiosa); Tailed frog (Ascopus truei); and Northern red-legged frog (Rana aurora).
Likewise there are a small number of reptilian taxa within the ecoregion: Common garter snake (Thamnophis sirtalis); Western terrestrial garter snake (Thamnophis sirtalis); Northern alligator lizard (Elgaria coerulea); Western fence lizard (Sceloporus occidentalis); Northwestern garter snake (Thamnophis ordinoides); Sharp-tailed snake (Contia tenuis); Yellow-bellied racer (Coluber constrictor); and Western pond turtle (Clemmys marmorata).
There are numberous mammalian taxa present in the Puget lowland forests. A small sample of these are:Creeping vole (Microtus oregoni), Raccoon (Procyon lotor), Southern sea otter (Enhydra lutris), Mink (Mustela vison), Coyote (Canis latrans), Black-tailed deer (Odocoileus hemionus), Pallid bat (Antrozous pallidus), and Harbour seal (Phoca vitulina).
A rich assortment of bird species present in this ecoregion, including the Near Threatened Spotted owl (Strix occidentalis), Turkey vulture (Cathartes aura), Bald eagle (Haliaeetus leucocephalus), Blue grouse (Dendragapus obscurus), as well as a gamut of seabirds, numerous shorebirds and waterfowl.
Sierra Nevada Forests
The Limestone salamander is a highly localized endemic of the Sierra Nevada forests foothills conifned to a limited reach of the Merced River. The Sierra Nevada forests are the forested areas of the Sierra Nevada Mountains, which run northwest to southwest and are approximately 650 kilometers long and 80 km wide. The range achieves its greatest height towards the south, with a number of peaks reaching heights of over 4000 meters. Several large river valleys dissect the western slope with dramatic canyons. The eastern escarpment is much steeper than the western slope, in general.
The Sierra Nevada forests ecoregion harbors one of the most diverse temperate conifer forests on Earth displaying an extraordinary range of habitat types and supporting many unusual species. Fifty percent of California's estimated 7000 species of vascular plants occur in the Sierra Nevada, with 400 Sierra endemics and 200 rare species. The southern section has the highest concentration of species and rare and endemic species, but pockets of rare plants occur throughout the range.
Sierra Nevada amphibian endemics are the Yosemite toad, Mount Lyell salamander (Hydromantes platycephalus), the Vulnerable Limestone salamander (Hydromantes brunus), Kern salamander and the Endangered Inyo Mountains salamander (Batrachoseps campi). The non endemic amphibians are: the Endangered Southern mountain yellow-legged frog (Rana muscosa); the Near Threatened Cascades frog (Rana cascadae); Northern red-legged frog (Rana aurora); Pacific chorus frog (Pseudacris regilia); Foothill Yellow-legged frog (Rana boylii); Long-toed salamander (Ambystoma macrodactylum); and the Monterey ensatina (Ensatina eschscholtzii).
A considerable number of mammalian taxa are found in the ecoregion, including the Long-eared chipmunk, Alpine chipmunk, Western heather vole, Walker Pass pocket mouse, and the Yellow-eared pocket-mouse. A diverse vertebrate predator assemblage once occurred in the ecoregion including Grizzly bear (Ursus arctos), Black bear (Ursus americanus), Coyote (Canis latrans), Mountain lion (Puma concolor), Ringtail (Bassariscus astutus), Fisher (Martes pennanti), Pine marten (Martes americana) and Wolverine (Gulo gulo).
There are a small number of reptilian taxa present in the Sierra Nevada forests: sagebrush lizard (Sceloporus graciosus); Northern alligator lizard (Elgaria coerulea); Southern alligator lizard (Elgaria multicarinata); Sharp-tailed snake (Contia tenuis); California mountain kingsnake (Molothrus ater); Common garter snake (Thamnophis sirtalis); Couch's garter snake (Thamnophis couchii); Western gopher snake (Pituophis catenifer); Longnose snake (Rhinocheilus lecontei); and the Common kingsnake (Lampropeltis getula).
A number of bird species are found in the ecoreion including high level predators that include several large owls, hawks and eagles. Other representative avifauna species present are the Blue-headed vireo (Vireo solitarius); Brown-headed cowbird (Molothrus ater); and the Near Threatened Cassin's finch (Carpodacus cassinii).
Montana Valley and Foothill Grasslands Habitat
This taxon can be found in the Montana valley and foothill grasslands ecoregions, along with some other North American ecoregions. This ecoregion occupies high valleys and foothill regions in the central Rocky Mountains of Montana in the USA and Alberta, Canada. The ecoregion the uppermost flatland reaches of the Missouri River drainage involving part of the Yellowstone River basin, and extends into the Clark Fork-Bitterroot drainage of the Columbia River system. The ecoregion, consisting of three chief disjunctive units, also extends marginally into a small portion of northern Wyoming. Having moderate vertebrate species richness, 321 different vertebrate taxa have been recorded here.
The dominant vegetation type of this ecoregion consists chiefly of wheatgrass (Agropyron spp.) and fescue (Festuca spp.). Certain valleys, notably the upper Madison, Ruby, and Red Rock drainages of southwestern Montana, are distinguished by extensive sagebrush (Artemisia spp.) communities as well. This is a reflection of semi-arid conditions caused by pronounced rain shadow effects and high elevation. Thus, near the Continental Divide in southwestern Montana, the ecoregion closely resembles the nearby Snake/Columbia shrub steppe.
A number of mammalian species are found in the ecoregion, including: American Pika (Ochotona princeps), a herbivore preferring talus habitat; Bighorn Sheep (Ovis canadensis), Black-tailed Prairie Dog (Cynomys ludovicianus), who live in underground towns that may occupy vast areas; Brown Bear (Ursos arctos); Hoary Marmot (Marmota caligata), a species who selects treeless meadows and talus as habitat; and the Northern River Otter (Lontra canadensis), a species that can tolerate fresh or brackish water and builds its den in the disused burrows of other animals.
There are six distinct anuran species that can be found in the Montana valleys and foothills grasslands, including: Canadian Toad (Anaxyrus hemiophrys); Western Toad (Anaxyrus boreas); Northern Leopard Frog (Lithobates pipiens); Plains Spadefoot Toad (Spea bombifrons); Columbia Spotted Frog (Rana luteiventris), an anuran that typically breeds in shallow quiet ponds; and the Boreal Chorus Frog (Pseudacris maculata).
Exactly two amphibian taxa occurr in the ecoregion: Long-toed Salamander (Ambystoma macrodactylum), a species who prefers lentic waters and spends most of its life hidden under bark or soil; Tiger Salamander (Ambystoma tigrinum).
Reptilian species within the ecoregion are: Milk Snake (Lampropeltis triangulum), an adaptable taxon that can be found on rocky slopes, prairie and near streambeds; Painted Turtle (Chrysemys picta); Western Plains Garter Snake (Thamnophis radix), a taxon that can hibernate in the burrows of rodents or crayfish or even hibernate underwater; Yellow-bellied Racer (Coluber constrictor); Spiny Softshell Turtle (Apalone spinifera); Western Terrestrial Garter Snake (Thamnophis elegans); Rubber Boa (Charina bottae); Western Skink (Plestiodon skiltonianus); and the Western Rattlesnake (Crotalis viridis).
The ecoregion supports endemic and relict fisheries: Westslope Cutthroat Trout (Oncorhynchus clarki lewisi), Yellowstone Cutthroat Trout (Oncorhynchus clarkii bouvieri), and fluvial Arctic Grayling (Thymallus arcticus), a relict species from past glaciation.
Palouse Grasslands Habitat
This taxon is found in the Palouse grasslands, among other North American ecoregions. The Palouse ecoregion extends over eastern Washington, northwestern Idaho and northeastern Oregon. Grasslands and savannas once covered extensive areas of the inter-mountain west, from southwest Canada into western Montana in the USA. Today, areas like the great Palouse prairie of eastern are virtually eliminated as natural areas due to conversion to rangeland. The Palouse, formerly a vast expanse of native wheatgrasses (Agropyron spp), Idaho Fescue (Festuca idahoensis), and other grasses, has been mostly plowed and converted to wheat fields or is covered by Drooping Brome (Bromus tectorum) and other alien plant species.
the Palouse historically resembled the mixed-grass vegetation of the Central grasslands, except for the absence of short grasses. Such species as Bluebunch Wheatgrass (Elymus spicatus), Idaho Fescue (Festuca idahoensis) and Giant Wildrye (Elymus condensatus) and the associated species Lassen County Bluegrass (Poa limosa), Crested Hairgrass (Koeleria pyramidata), Bottlebrush Squirrel-tail (Sitanion hystrix), Needle-and-thread (Stipa comata) and Western Wheatgrass (Agropyron smithii) historically dominated the Palouse prairie grassland.
Representative mammals found in the Palouse grasslands include the Yellow-bellied Marmot (Marmota flaviventris), found burrowing in grasslands or beneath rocky scree; American Black Bear (Ursus americanus); American Pika (Ochotona princeps); Coast Mole (Scapanus orarius), who consumes chiefly earthworms and insects; Golden-mantled Ground Squirrel (Spermophilus lateralis); Gray Wolf (Canis lupus); Great Basin Pocket Mouse (Perognathus parvus); Northern River Otter (Lontra canadensis); the Near Threatened Washington Ground Squirrel (Spermophilus washingtoni), a taxon who prefers habitat with dense grass cover and deep soils; and the Northern Flying Squirrel (Glaucomys sabrinus), a mammal that can be either arboreal or fossorial.
There are not a large number of amphibians in this ecoregion. The species present are the Great Basin Spadefoot Toad (Spea intermontana), a fossorial toad that sometimes filches the burrows of small mammals; Long-toed Salamander (Ambystoma macrodactylum); Northern Leopard Frog (Glaucomys sabrinus), typically found near permanent water bodies or marsh; Columbia Spotted Frog (Rana luteiventris), usually found near permanent lotic water; Pacific Treefrog (Pseudacris regilla), who deposits eggs on submerged plant stems or the bottom of water bodies; Tiger Salamander (Ambystoma tigrinum), fossorial species found in burrows or under rocks; Woodhouse's Toad (Anaxyrus woodhousii), found in arid grasslands with deep friable soils; Western Toad (Anaxyrus boreas), who uses woody debris or submerged vegetation to protect its egg-masses.
There are a limited number of reptiles found in the Palouse grasslands, namely only: the Northern Alligator Lizard (Elgaria coerulea), often found in screes, rock outcrops as well as riparian vicinity; the Painted Turtle (Chrysemys picta), who prefers lentic freshwater habitat with a thick mud layer; Yellow-bellied Racer (Chrysemys picta); Ringneck Snake (Diadophis punctatus), often found under loose stones in this ecoregion; Pygmy Short-horned Lizard (Phrynosoma douglasii), a fossorial taxon often found in bunchgrass habitats; Side-blotched Lizard (Uta stansburiana), frequently found in sandy washes with scattered rocks; Southern Alligator Lizard (Elgaria multicarinata), an essentially terrestrial species that prefers riparian areas and other moist habitats; Pacific Pond Turtle (Emys marmorata), a species that usually overwinters in upland habitat; Western Rattlesnake (Crotalus viridis), who, when inactive, may hide under rocks or in animal burrows; Night Snake (Hypsiglena torquata); Western Skink (Plestiodon skiltonianus), who prefers grasslands with rocky areas; Western Terrestrial Garter Snake (Thamnophis elegans), found in rocky grasslands, especially near water; Rubber Boa (Charina bottae).
Habitat and Ecology
Central Pacific Coastal Forests Habitat
This taxon is found in the Central Pacific Coastal Forests ecoregion, as one of its North American ecoregions of occurrence. These mixed conifer rainforests stretch from stretch from southern Oregon in the USA to the northern tip of Vancouver Island, Canada. These forests are among the most productive in the world, characterized by large trees, substantial woody debris, luxuriant growths of mosses and lichens, and abundant ferns and herbs on the forest floor. The major forest complex consists of Douglas-fir (Pseudotsuga menziesii) and Western hemlock (Tsuga heterophylla), encompassing seral forests dominated by Douglas-fir and massive old-growth forests of Douglas-fir, Western hemlock, Western red cedar (Thuja plicata), and other species. These forests occur from sea level up to elevations of 700-1000 meters in the Coast Range and Olympic Mountains. Such forests occupy a gamut of environments with variable composition and structure and includes such other species as Grand fir (Abies grandis), Sitka spruce (Picea sitchensis), and Western white pine (Pinus monticola).
Characteristic mammalian fauna include Elk (Cervus elaphus), Black-tailed Deer (Odocoileus hemionus), Coyote (Canis latrans), Black Bear (Ursus americanus), Mink (Mustela vison), and Raccoon (Procyon lotor).
The following anuran species occur in the Central Pacific coastal forests: Coastal tailed frog (Ascaphus truei); Oregon spotted frog (Rana pretiosa VU); Northern red-legged frog (Rana pretiosa); Pacific chorus frog (Pseudacris regilla); Cascade frog (Rana cascadae NT), generally restricted to the Cascade Range from northern Washington to the California border; Foothill yellow-legged frog (Rana boylii) and the Western toad (Anaxyrus boreas NT). A newt found in the ecoregion is the Rough skinned newt (Taricha granulosa).
Salamanders within the ecoregion are: Del Norte salamander (Plethodon elongatus NT); Van Dyke's salamander (Plethodon vandykei); Western redback salamander (Plethodon vehiculum); Northwestern salamander (Ambystoma gracile); Olympic torrent salamander (Rhyacotriton olympicus VU), whose preferred habitat is along richly leafed stream edges; Long-toed salamander (Ambystoma macrodactylum), whose adults are always subterranean except during the breeding season; Dunn's salamander (Plethodon dunni), usually found in seeps and stream splash zones; Clouded salamander (Aneides ferreus NT), an aggressive insectivore; Monterey ensatina (Ensatina eschscholtzii), usually found in thermally insulated micro-habitats such as under logs and rocks; Pacific giant salamander (Dicamptodon tenebrosus), found in damp, dense forests near streams; and Cope's giant salamander (Dicamptodon copei), usually found in rapidly flowing waters on the Olympic Peninsula and Cascade Range.
There are a small number of reptilian taxa that are observed within this forested ecoregion, including: Pacific pond turtle (Emys marmorata); Common garter snake (Thamnophis sirtalis), an adaptable snake most often found near water; Northern alligator lizard (Elgaria coerulea); and the Western fence lizard.
Numerous avian species are found in the ecoregion, both resident and migratory. Example taxa occurring here are the Belted kingfisher (Megaceryle alcyon); Wild turkey (Meleagris gallopavo); and the White-headed woodpecker (Picoides albolarvatus) and the Trumpeter swan (Cygnus buccinator), the largest of the North American waterfowl.
Comments: Found in a wide variety of habitats, from semiarid sagebrush deserts to sub-alpine meadows, including dry woodlands, humid forests, and rocky shores of mountain lakes. Adults are subterranean except during the breeding season. A terrestrial habitat use survey near Hinton, Alberta determined that individuals were found primarily in well-drained areas with thick litter on the forest floor and close to relatively permanent water bodies (Graham 1997). Salamanders were also found in seral stages ranging from three-year-old clear-cuts to 180-year-old forests and occurred in active logging areas (Graham 1997). Breeds in temporary or permanent ponds, or in quiet water at the edge of lakes and streams. During the breeding season adults may be found under logs, rocks, and other debris near water. Eggs are attached to vegetation or loose on bottom.
Since they are highly susceptible to desiccation, adult and subadult long-toed salamanders spend most of their lives underground or beneath objects. Larvae use submerged objects and aquatic vegetation for cover .
Southern long-toed salamander larvae generally remain hidden under bark, logs, or other submerged objects. They overwinter beneath such objects, in water more than 12 inches (30 cm) deep. In mid-summer in Calaveras County, California, subadults sought cover beneath objects in dried temporary ponds; they were never found outside pond perimeters. In late summer, subadults were still beneath objects in the dried ponds but had formed ball-shaped aggregations of 15 to 43 individuals. Adults used large, rotting logs for cover most of the year .
Santa Cruz long-toed salamander larvae in Santa Cruz County use dense aquatic vegetation and turbid water for cover. Subadults cannot disperse to coast live oak woodlands immediately after transformation due to arid summer climate. After summer metamorphosis, they retreat to willow thickets at shore edges or beneath matted vegetation or other debris at the bottoms of drying ponds. When these substrates dry, subadults seek the same substrates used by adults in summer: rodent burrows, buried logs, dense tule (Scirpus acutus) mats, or other microhabitats where moisture is retained throughout the dry season. Subadults often aggregate at these sites, tightly entwined in groups of three to nine individuals. With onset of autumn rains, subadults move into coast live oak woodlands . Adult Santa Cruz salamanders in Monterey County have been found in willow thickets and beneath wooden boxes and other urban debris during the dry season .
General: Long-toed salamanders occur in diverse habitats including coniferous forest, oak (Quercus spp.) woodland, alpine, sagebrush (Artemisia spp.), and marshland communities [2,26]. They use springs, ponds, small lakes, slow-moving streams, and marshlands for breeding and larval development [2,5].
Habitat of Subspecies:
Eastern long-toed salamanders occur in ponderosa pine, lodgepole pine, and subalpine fir-Engelmann spruce (Abies lasiocarpa-Picea engelmannii) zones. A population near Moscow, Idaho, used artificial ponds within ponderosa pine-grand fir (A. grandis) forest for breeding . Eastern long-toed salamanders have also been documented in wheatfields (Triticum aestivus) with irrigation ponds, ponderosa pine-big sagebrush (Artemisia tridentata) woodlands with temporary ponds, and sparsely vegetated whitebark pine-mountain heather (Pinus albicaulis-Phyllodoce empetriformis) communities with permanent lakes [12,13]. Long-toed salamander larvae, presumably eastern long-toed salamanders, were found in a spring within a cottonwood-quaking aspen (Populus spp.-P. tremuloides) riparian community on the Bruneau Resource Area of southern Idaho .
The southern long-toed salamander occurs in mixed Sierra Nevada coniferous forest and alpine communities. It has been noted at 8,075 feet (2,750 m) elevation in Alpine County, California. A population at 6,534 feet (1980 m) elevation in Calaveras County, California, occurred in and near a temporary pond formed from snowmelt. The pond was shaded by large trees, including white fir (Abies concolor), ponderosa pine (Pinus ponderosa), lodgepole pine (P. contorta), and quaking aspen, that provided shade for most of the day. The pond was clear and moderately acidic (pH 5.9). It lacked aquatic vegetation and was littered with needles and small woody debris. Further east, a population occurring at 8,085 feet (2,450 m) in Alpine County, California, occupied permanent ponds fed by snowmelt and springs. Lodgepole pine, western white pine (Pinus monticola), and mountain hemlock (Tsuga mertensiana) were sparse to numerous around pond margins but always provided at least some shade. The pond waters were very clear, lacking live vegetation but with considerable downed woody debris including floating and submerged logs .
Santa Cruz long-toed salamanders in the two Santa Cruz County populations occur in and near temporary ponds in coast live oak (Quercus agrifolia) woodlands [2,21]. Pond waters are often turbid and aquatic plant growth is extensive. In summer, adults seek moist areas such as seeps and willow (Salix spp.) thickets near pond shores . The Monterey County population occurs in a cattail-bulrush (Typha-Scirpus spp.) marsh .
Habitat: Rangeland Cover Types
This species is known to occur in association with the following Rangeland Cover Types (as classified by the Society for Range Management, SRM):
109 Ponderosa pine shrubland
110 Ponderosa pine-grassland
202 Coast live oak woodland
203 Riparian woodland
213 Alpine grassland
216 Montane meadows
401 Basin big sagebrush
409 Tall forb
411 Aspen woodland
906 Broadleaf forest
Habitat: Plant Associations
This species is known to occur in association with the following plant community types (as classified by Küchler 1964):
More info for the term: shrub
K001 Spruce-cedar-hemlock forest
K002 Cedar-hemlock-Douglas-fir forest
K003 Silver fir-Douglas-fir forest
K004 Fir-hemlock forest
K005 Mixed conifer forest
K007 Red fir forest
K008 Lodgepole pine-subalpine forest
K009 Pine-cypress forest
K010 Ponderosa shrub forest
K011 Western ponderosa forest
K012 Douglas-fir forest
K013 Cedar-hemlock-pine forest
K014 Grand fir-Douglas-fir forest
K015 Western spruce-fir forest
K018 Pine-Douglas-fir forest
K025 Alder-ash forest
K026 Oregon oakwoods
K028 Mosaic of K002 and K026
K029 California mixed evergreen forest
K030 California oakwoods
K049 Tule marshes
K052 Alpine meadows and barren
K055 Sagebrush steppe
This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):
FRES21 Ponderosa pine
FRES22 Western white pine
FRES24 Hemlock-Sitka spruce
FRES26 Lodgepole pine
FRES28 Western hardwoods
FRES36 Mountain grasslands
FRES37 Mountain meadows
FRES41 Wet grasslands
Habitat: Cover Types
This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):
205 Mountain hemlock
206 Engelmann spruce-subalpine fir
207 Red fir
208 Whitebark pine
210 Interior Douglas-fir
211 White fir
212 Western larch
213 Grand fir
215 Western white pine
218 Lodgepole pine
221 Red alder
222 Black cottonwood-willow
223 Sitka spruce
224 Western hemlock
225 Western hemlock-Sitka spruce
226 Coastal true fir-hemlock
227 Western redcedar-western hemlock
228 Western redcedar
229 Pacific Douglas-fir
230 Douglas-fir-western hemlock
233 Oregon white oak
234 Douglas-fir-tanoak-Pacific madrone
237 Interior ponderosa pine
243 Sierra Nevada mixed conifer
244 Pacific ponderosa pine-Douglas-fir
245 Pacific ponderosa pine
246 California black oak
247 Jeffrey pine
255 California coast live oak
256 California mixed subalpine
Associated Plant Communities
Non-Migrant: No. All populations of this species make significant seasonal migrations.
Locally Migrant: Yes. At least some populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
Migrates between breeding ponds and nonbreeding habitat; usually migrates at night in conjunction with precipitation. Males reach ponds before females and stay longer.
Comments: Larvae feed on zooplankton, immature insects, snails, and occasionally other salamander larvae, including conspecifics. Adults eat terrestrial and aquatic invertebrates including: insects, insect larvae, spiders, slugs, earthworms, amphipods, etc.
Adult long-toed salamanders hunt terrestrial and aquatic arthropods. They also scavenge dead arthropods [19,30]. The diet of larvae is similar: larvae consume aquatic arthropods and terrestrial arthropods that fall into the water, and scavenge arthropod remains. In addition, some long-toed salamander larvae are cannibalistic. Cannibal larvae are morphologically different from "normal" larvae, having larger heads and jaws, reduced gills, and a more slender body. Larvae may become cannibalistic in response to either high larval population density or a scarcity of other food sources .
In summer, proteins and fats are stored in the tails of long-toed salamanders. These nutrients are metabolized during long periods of dormancy .
Eastern long-toed salamander larvae in Oregon have been observed feeding on hatchling Pacific treefrog (Hyla regilla) larvae. Cascades frog (Rana cascadae) larvae and fairy shrimp (Anostraca) were other potential prey in the breeding pond .
Adult long-toed salamanders are probably not highly vulnerable to predation. Except during migration, they are secretive in habit. Even then, they migrate to and from breeding ponds at night, in winter or during spring snowmelt, when most predators that would potentially prey on long-toed salamander are relatively inactive . Additionally, long-toed salamanders secrete a toxin from glands in their tails when captured; the toxin often prompts predators to drop and abandon the long-toed salamanders .
Near Moscow, Idaho, a common garter snake (Thamnophis sirtalis) was observed in the process of swallowing an eastern long-toed salamander. Other potential predators captured near breeding ponds were western terrestrial garter snakes (T. elgans) and shrews (Sorex spp.). However, these predators were not active until late April, when all but a few male long-toed salamanders had already departed from breeding ponds and returned to forest cover .
Long-toed salamander larvae prey upon each other [2,5].
Number of Occurrences
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Estimated Number of Occurrences: 81 to >300
Comments: Many occurrences.
100,000 - 1,000,000 individuals
Comments: Total adult population size is unknown but likely exceeds 100,000.
Predators of larvae probably include aquatic insects and garter snakes; garter snakes and bullfrogs eat adults (Nussbaum et al. 1983).
Habitat-related Fire Effects
Adult and subadult long-toed salamanders use logs and large branches for cover, and larvae use floating and submerged downed woody debris of all size classes for cover . Fire that increases downed woody debris while retaining some overhead shade probably improves habitat structure of long-toed salamanders.
Timing of Major Life History Events
Life span: A sampling of adults and subadults (individuals that have metamorphosed but not yet reached sexual maturity) in a northern long-toed salamander population in Alberta showed an age distribution from 1 year to 10 years of age, with most individuals in the 2- to 3-year-old age bracket .
Life History - General: Life histories of long-toed salamanders vary with temperature and moisture conditions. Several life history patterns are evident: a one-season larval period (in warm climates); either a short facultative one-season larval period or a two-season larval period (moderate climates); and a three- to four-season larval period (cold climates). In warm climates, period of development is limited by precipitation. Breeding cannot take place until temporary ponds fill. Variation in rainfall determines the length of time water remains and, therefore, period of larval development. Metamorphosis occurs when ponds begin to shrink . In cold climates, development time extends to several years due to short growing season. Regardless of subspecies, long-toed salamander larvae do not transform until attaining a snout-to-vent length of at least 33 mm. In cold climates, it may take 4 years to reach that size .
Life History of Subspecies:
Eastern long-toed salamanders - In ponderosa pine forest near Moscow, Idaho, migration to breeding ponds began in late February. By late April, most adults had left the ponds . Howard and Wallace  reported that low-elevation (1,390 feet (420 m)) populations in Nez Perce County, Idaho, bred in early February; mid-elevation (3,760 feet (1140 m)) populations in Baker County, Oregon, bred in April; and high-elevation (8,150 feet (2470 m)) populations in Wallowa County, Oregon, bred in June and July. Females at high-elevation sites laid fewer, larger eggs than females at lower-elevation sites. Number of eggs per female averaged 166 (SD +/- 60) at the 1,390-foot site and 90 (SD +/-49) at the 8,150-foot site. Larvae from populations below 6,930 feet (2100 m) metamorphosed in their first summer, while larvae from higher elevations metamorphosed in late summer of their third or fourth year.
Northern long-toed salamanders - A sample of wild individuals in Alberta reached sexual maturity at 47 mm in length, a length attained at about 3 years of age. Well-fed, captive individuals, raised in aquaria from eggs, exceeded 47 mm in length by their first year but did not reach sexual maturity until their second year .
Southern long-toed salamanders - Populations in the Sierra Nevada have facultative one-season and two-season larval periods. In Calaveras County, California, at 6,530 feet (1980 m) elevation, time from egg deposition to metamorphosis was 80 to 90 days in temporary ponds. Larval period is probably longer at that elevation in large, permanent ponds. At higher elevations, southern long-toed salamanders do not reach the critical size for metamorphosis in a single season. In Alpine County, California, (elevation 8,085 feet (2450 m)), mating and egg deposition occurs from late May to late June, as soon as ponds partially thaw. Larvae develop in summer and spend the winter beneath ice, transforming in August or September of their second year. Adults first reproduce at age 2 or 3 .
Santa Cruz long-toed salamanders - Living in a mediterranean climate, Santa Cruz long-toed salamanders experience one of the driest environments of the species. Larval development is completed within one season. In drought years, rainfall is sometimes insufficient to allow normal breeding and larval development to occur. In wetter years, migration to breeding ponds begins with late fall and winter rains. Santa Cruz long-toed salamanders only migrate on rainy nights. Subadults move to ponds after light rains, but adults migrate only after heavy, ground-soaking rains. Breeding occurs from January to mid-February and eggs hatch from late February to mid-March. Time from breeding to larval transformation and pond shrinkage varies from about 90 to 140 days. Santa Cruz long-toed salamanders are sexually mature at age 2 .
Direct Effects of Fire
If caught in the open during a fire, long-toed salamanders would probably be killed. They are very slow-moving , and probably cannot escape even slow-moving fire. Even if missed by fire, they probably could not survive the heat. High temperatures are lethal to long-toed salamanders. In the laboratory, adults from northeastern Oregon and western Idaho were killed by water temperatures that ranged from above 91 to 96 degrees Fahrenheit (33-36 oC) .
Life History and Behavior
Comments: May be active almost all winter in Pacific Northwest coastal ponds (Stebbins 1985).
Lifespan, longevity, and ageing
Breeding season is longer and earlier (fall-early spring) in coastal lowlands, shorter and later (summer) in interior mtns. Clutch size is larger at lower elevations (Howard and Wallace 1985). Larvae metamorphose in first summer or overwinter (high elevations). In Alberta, sexually mature in 2+ years; maximum life span 10 years, usually 6 years or less (Russell et al. 1996).
Molecular Biology and Genetics
Statistics of barcoding coverage: Ambystoma macrodactylum
Public Records: 0
Specimens with Barcodes: 10
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
National NatureServe Conservation Status
Rounded National Status Rank: N4 - Apparently Secure
Rounded National Status Rank: N5 - Secure
NatureServe Conservation Status
Rounded Global Status Rank: G5 - Secure
Intrinsic Vulnerability: Moderately vulnerable
Environmental Specificity: Narrow. Specialist or community with key requirements common.
U.S. Federal Legal Status
Global Short Term Trend: Relatively stable to decline of 30%
Comments: Trends have not been well documented in most of the range, but area of occupancy, number of subpopulations, and population size probably are relatively stable or declining at a rate of less than 30 percent over 10 years or three generations.
Global Long Term Trend: Relatively stable to decline of 50%
Life History, Abundance, Activity, and Special Behaviors
Life history varies greatly with elevation and climate. Each season individuals migrate to breeding ponds with males arriving earlier and staying longer than females (Beneski et al 1986). At low elevations this migration may be in October or November, but at higher elevations it does not occur until snowmelt in late spring (Petranka 1998). Males deposit spermatophores (packets of sperm) which females pick up after courtship. Single eggs or loose egg clumps are attached to vegetation or detritus. Larvae hatch 2-5 weeks later and metamorphose in about 3 months (Petranka 1998).
Degree of Threat: Medium
Comments: In the Cascades of northern Washington, larval abundance was related to both lake productivity and the presence of introduced trout (reduced larval abundance when trout present) (Tyler et al. 1998). In Montana, introduced trout populations clearly excluded salamanders from lakes (Funk and Dunlap 1999).
In developed areas, the destruction of wetland habitats may be the greatest threat. Human disturbance such as road and trail construction, timber harvest, grazing, and fire management may result in fragmentation of terrestrial habitat and breeding ponds (Fukumoto 1995 in Graham and Powell 1999, Maxell 2000, Paton 2002).
Larvae are sensitive to a combination of low pH and aluminum.
In the Pacific Northwest, this species appears to be particularly sensitive to UV-B exposure (Belden et al. 2000). Possible effects of exposure to UV-B include increased mortality and incidence of deformities, slowed growth, and skin darkening (Belden and Blaustein 2002).
Life History, Abundance, Activity, and Special Behaviors
Eggs exposed to ambient levels of UV-B radiation have been shown to have increased mortality and incidence of deformities than those shielded from UV-B (Blaustein et al 1997). A trematode has been found that disrupts both limb development and regeneration and has been proposed as an explanation of why individuals with supernumerary limbs are found (Sessions and Ruth 1990). Environmental contaminants as well as the introduction of non-native fish predators may also threaten this species. The destruction of wetland habitats may prove to be the greatest threat. The subspecies, A. m. croceum, persists in only a few scattered populations and is threatened with extinction (Petranka 1998).
Restoration Potential: In Montana, salamanders recolonized high-elevation lakes after the extirpation of introduced trout (Funk and Dunlap 1999).
Management Requirements: Fisheries management could improve the status of salamander populations by not introducing fishes into salamander habitats where fishes are not native. Removal of non-native fishes from otherwise favorable salamander habitat is appropriate in many locations.
Fisheries management could improve the status of salamander populations by preventing introduction of fishes into salamander habitats where fishes are not native. Removal of non-native fishes from otherwise favorable salamander habitat is appropriate in many locations. Montana researchers recommend using only herbicide and pesticide brands that rapidly decompose and not spraying within 300m of water bodies or wetlands (Joslin and Youmans 1999 in Paton 2002). Logging activities in areas with long-toed salamanders should be scheduled to occur during the winter to minimize soil compaction and litter layer disturbance (Graham 1997, Paton 2002).
Management Research Needs: Information on genetic variation on a large scale (subspecies) and population scale would be useful for management decision-making (Graham and Powell 1999)
Biological Research Needs: Since there can be significant year to year variation in population size, long-term monitoring is necessary to determine population trends (Graham and Powell 1999, Paton 2002).
Global Protection: Several to very many (4 to >40) occurrences appropriately protected and managed
Comments: In British Columbia, protection occurs through the Wildlife Act, which includes all native amphibians (Graham and Powell 1999). In Alberta, long-toed salamanders are designated a sensitive species (Pearson 2003).
Needs: Would benefit from protection of habitat near breeding ponds (Bury et al. 1980). Prohibit introductions of non-native fishes in salamander habitat.
The long-toed salamander (Ambystoma macrodactylum, Baird 1849) is a mole salamander in the family Ambystomatidae. This species, typically 4.1–8.9 cm (1.6 to 3.5 in) long when mature, is characterized by its mottled black, brown, and yellow pigmentation, and its long outer fourth toe on the hind limbs. Analysis of fossil records, genetics, and biogeography suggest A. macrodactylum and A. laterale are descended from a common ancestor that gained access to the western Cordillera with the loss of the mid-continental seaway toward the Paleocene.
The distribution of the long-toed salamander is primarily in the Pacific Northwest, with an altitudinal range of up to 2,800 m (9,200 ft). It lives in a variety of habitats, including temperate rainforests, coniferous forests, montane riparian zones, sagebrush plains, red fir forests, semiarid sagebrush, cheatgrass plains, and alpine meadows along the rocky shores of mountain lakes. It lives in slow-moving streams, ponds, and lakes during its aquatic breeding phase. The long-toed salamander hibernates during the cold winter months, surviving on energy reserves stored in the skin and tail.
The five subspecies have different genetic and ecological histories, phenotypically expressed in a range of color and skin patterns. Although the long-toed salamander is classified as a species of Least Concern by the IUCN, many forms of land development threaten and negatively affect the salamander's habitat.
- 1 Taxonomy
- 2 Description
- 3 Habitat and distribution
- 4 Ecology and life cycle
- 5 Behaviour
- 6 Conservation status
- 7 Systematics and Biogeography
- 8 See also
- 9 Notes
- 10 External links
A. macrodactylum is a member of the Ambystomatidae, also known as the mole salamanders. The Ambystomatidae originated approximately 81 million years ago (late Cretaceous) from its sister taxon Dicamptodontidae. The Ambystomatidae are also members of suborder Salamandroidea, which includes all the salamanders capable of internal fertilization. The sister species to A. macrodactylum is A. laterale, distributed in eastern North America. However, the species-level phylogeny for Ambystomatidae is tentative and in need of further testing.
The body of the long-toed salamander is dusky black with a dorsal stripe of tan, yellow, or olive-green. This stripe can also be broken up into a series of spots. The sides of the body can have fine white or pale blue flecks. The belly is dark-brown or sooty in color with white flecks. Root tubercles are present, but they are not quite as developed as other species, such as the tiger salamander.
The eggs of this species look similar to those of the related northwestern salamander (A. gracile) and tiger salamander (A. tigrinum). Like many amphibians, the eggs of the long-toed salamander are surrounded by a gelatinous capsule. This capsule is transparent, making the embryo visible during development. Unlike A. gracile eggs, there are no visible signs of green algae, which makes egg jellies green in color. When in its egg, the long-toed salamander embryo is darker on top and whiter below compared to a tiger salamander embryo that is light brown to grey above and cream-colored on the bottom. The eggs are about 2 mm (0.08 in) or greater in diameter with a wide outer jelly layer. Prior to hatching—both in the egg and as newborn larvae—they have balancers, which are thin skin protrusions sticking out the sides and supporting the head. The balancers eventually fall off and their external gills grow larger. Once the balancers are lost the larvae are distinguished by the sharply pointed flaring of the gills. As the larvae mature and metamorphose, their limbs with digits become visible and the gills are resorbed.
The skin of a larva is mottled with black, brown, and yellow pigmentation. Skin color changes as the larvae develop and pigment cells migrate and concentrate in different regions of the body. The pigment cells, called chromatophores, are derived from the neural crest. The three types of pigment chromatophores in salamanders include yellow xanthophores, black melanophores, and silvery iridiophores (or guanophores). As the larvae mature, the melanophores concentrate along the body and provide the darker background. The yellow xanthophores arrange along the spine and on top of the limbs. The rest of the body is flecked with reflective iridiophores along the sides and underneath.
As larvae metamorphose, they develop digits from their limb bud protrusions. A fully metamorphosed long-toed salamander has four digits on the front limbs and five digits on the rear limbs. Its head is longer than it is wide, and the long outer fourth toe on the hind limb of mature larvae and adults distinguishes this species from others and is also the etymological origin of its specific epithet: macrodactylum (Greek makros = long and daktylos = toe). The adult skin has a dark brown, dark grey, to black background with a yellow, green, or dull red blotchy stripe with dots and spots along the sides. Underneath the limbs, head, and body the salamander is white, pinkish, to brown with larger flecks of white and smaller flecks of yellow. Adults are typically 3.8–7.6 cm (1.5–3.0 in) long.
Habitat and distribution
The long-toed salamander is an ecologically versatile species living in a variety of habitats, ranging from temperate rainforests, coniferous forests, montane riparian, sagebrush plains, red fir forest, semiarid sagebrush, cheatgrass plains, to alpine meadows along the rocky shores of mountain lakes. Adults can be located in forested understory, hiding under coarse woody debris, rocks, and in small mammal burrows. During the spring breeding season, adults can be found under debris or in the shoreline shallows of rivers, streams, lakes, and ponds. Ephemeral waters are often frequented.
This species is one of the most widely distributed salamanders in North America, second only to the tiger salamander. Its altitudinal range runs from sea level up to 2,800 meters (9,200 ft), spanning a wide variety of vegetational zones. The range includes isolated endemic populations in Monterey Bay and Santa Cruz, California. The distribution reconnects in northeastern Sierra Nevada running continuously along the Pacific Coast to Juneau, Alaska, with populations dotted along the Taku and Stikine River valleys. From the Pacific coast, the range extends longitudinally to the eastern foothills of the Rocky Mountains in Montana and Alberta.
Ecology and life cycle
Like all amphibians, the life of a long-toed salamander begins as an egg. In the northern extent of its range, the eggs are laid in lumpy masses along grass, sticks, rocks, or the mucky substrate of a calm pond. The number of eggs in a single mass ranges in size, possibly up to 110 eggs per cluster. Females invest a significant amount of resources into egg production, with the ovaries accounting for over 50% of the body mass in the pre-breeding season. A maximum of 264 eggs have been found in a single female—a large number considering each egg is approximately 0.5 millimeters (0.02 in) in diameter. The egg mass is held together by a gelatinous outer layer protecting the outer capsule of individual eggs. The eggs are sometimes laid singly, especially in warmer climates south of the Canada and US border. The egg jellies contribute a yearly supply of biological material that supports the chemistry and nutrient dynamics of shallow-water aquatic ecosystems and adjacent forest ecosystems. The eggs also provide habitat for water molds, also known as oomycetes.
Larvae hatch from their egg casing in two to six weeks. They are born carnivores, feeding instinctively on small invertebrates that move in their field of vision. Food items include small aquatic crustaceans (cladocerans, copepods and ostracods), aquatic dipterans and tadpoles. As they develop, they naturally feed upon larger prey. To increase their chances for survival, some individuals grow bigger heads and become cannibals, and feed upon their own brood mates.
Metamorphosis and juveniles
After the larvae grow and mature, for at least one season (the larval period lasts about four months on the Pacific coast), they absorb their gills and metamorphose into terrestrial juveniles that roam the forest undergrowth. Metamorphosis has been reported as early as July at sea level, for A. m. croceum in October to November and even January. At higher elevations the larvae may overwinter, develop, and grow for an extra season before metamorphosing. In lakes at higher elevations, the larvae can reach sizes of 47 millimeters (1.9 in) snout to vent length (SVL) at metamorphosis, but at lower elevations they develop faster and metamorphose when they reach 35–40 millimeters (1.4–1.6 in) SVL.
As adults, long-toed salamanders often go unnoticed because they live a subterranean lifestyle digging, migrating, and feeding on the invertebrates in forest soils, decaying logs, small rodent burrows or rock fissures. The adult diet consists of insects, tadpoles, worms, beetles and small fish. Salamanders are preyed upon by garter snakes, small mammals, birds, and fish. An adult may live 6–10 years, with the largest individuals weighing approximately 7.5 grams (0.26 oz), snout to vent lengths reaching 8 cm (3.1 in), and total lengths reaching 14 cm (5.5 in).
The life history of the long-toed salamander varies greatly with elevation and climate. Seasonal dates of migration to and from the breeding ponds can be correlated with bouts of sustained rainfall, ice thaw, or snow melt sufficient to replenish the (often) seasonal ponds. Eggs may be spawned at low elevations as early as mid-February in southern Oregon, from early January to July in northwestern Washington, from January to March in southeastern Washington, and from mid-April to early May in Waterton Lakes National Park, Alberta. The timing of breeding can be highly variable; of notable mention, several egg masses in early stages of development were found on July 8, 1999 along the British Columbia provincial border outside Jasper, Alberta. Adults migrate seasonally to return to their natal breeding ponds, with males arriving earlier and staying longer than females, and some individuals have been seen migrating along snow banks on warm spring days. Gender differences (or sexual dimorphism) in this species are only apparent during the breeding season, when mature males display an enlarged or bulbous vent area.
The time of breeding depends on the elevation and latitude of the salamander's habitat. Generally, the lower-elevation salamanders breed in the fall, winter, and early spring. Higher-elevation salamanders breed in spring and early summer. In the higher climates especially, salamanders will enter ponds and lakes that still have ice floating.
Adults aggregate in large numbers (>20 individuals) under rocks and logs along the immediate edge of the breeding sites and breed explosively over a few days. Suitable breeding sites include small fish-free ponds, marshes, shallow lakes and other still-water wetlands. Like other ambystomatid salamanders, they have evolved a characteristic courtship dance where they rub bodies and release pheromones from their chin gland prior to assuming a copulatory mating position. Once in position, the male deposits a spermatophore, which is a gooey stalk tipped with a packet of sperm, and walks the female forward to be inseminated. Males may mate more than once and may deposit as many as 15 spermatophores over the course of a five-hour period. The courtship dance for the long-toed salamander is similar to other species of Ambystoma and very similar to A. jeffersonianum. In the long-toed salamander, there is no rubbing or head-butting; the males directly approach females and grab on, while the females try to rapidly swim away. The males clasp the female from behind the forelimbs and shake, a behavior called amplexus. Males sometimes clasp other amphibian species during breeding and shake them as well. The male only grabs with the front limbs and never uses his hind limbs during the courtship dance as he rubs his chin side to side pressing down on the female's head. The female struggles but later becomes subdued. Males increase the tempo and motions, rubbing over the female's nostrils, sides, and sometimes the vent. When the female becomes quite docile the male moves forward with his tail positioned over her head, raised, and waving at the tip. If the female accepts the males courtship, the male directs her snout toward his vent region while both move forward stiffly with pelvic undulations. As the female follows, the male stops and deposits a spermatophore, and the female will move forward with the male to raise her tail and receive the sperm packet. The full courtship dance is rarely accomplished in the first attempt. Females deposit their eggs a few days after mating.
Energy storage and defense mechanisms
In some lowland areas the adult salamanders will remain active all winter long, excluding cold spells. However, during the cold winter months in the northern parts of its range, the long-toed salamander burrows below the frost-line in a coarse substrate to hibernate in clusters of 8–14 individuals. While hibernating, it survives on protein energy reserves that are stored in its skin and along its tail. These proteins serve a secondary function as part of a mixture or concoction of skin secretions that is used for defense. When threatened, the long-toed salamander will wave its tail and secrete an adhesive white milky substance that is noxious and likely poisonous. The color of its skin can serve as a warning to predators (aposematism) that it will taste bad. Its skin colors and patterns are diverse, ranging from a dark black to reddish brown background that is spotted or blotched by a pale-reddish-brown, pale-green, to a bright yellow stripe. An adult may also drop part of its tail and slink away while the tail bit acts as a squirmy decoy; this is called autotomy. The regeneration and regrowth of the tail is one example of the developmental physiology of amphibians that is of great interest to the medical profession.
While the long-toed salamander is classified as least concern by the IUCN, many forms of land development negatively affect the salamander's habitat and have put new perspectives and priorities into its conservation biology. Conservation priorities focus at the population level of diversity, which is declining at rates ten times that of species extinction. Population level diversity is what provides ecosystem services, such as the keystone role that salamanders play in the soil ecosystems, including the nutrient cycling that supports wetland and forested ecosystems.
Two life-history features of amphibians are often cited as a reason why amphibians are good indicators of environmental health or 'canaries in the coal mine'. Like all amphibians, the long-toed salamander has both an aquatic and terrestrial life transition and semipermeable skin. Since they serve different ecological functions in the water than they do in land, the loss of one amphibian species is equivalent to the loss of two ecological species. The second notion is that amphibians, such as long-toed salamanders, are more susceptible to the absorption of pollutants because they naturally absorb water and oxygen through their skin. The validity of this special sensitivity to environmental pollutants, however, has been called into question. The problem is more complex, because not all amphibians are equally susceptible to environmental damage because there is such a diverse array of life histories among species.
Long-toed salamander populations are threatened by fragmentation, introduced species, and UV radiation. Forestry, roads, and other land developments have altered the environments that amphibians migrate to, and have increased mortality. Places such as Waterton Lakes National Park have installed a road tunnel underpass to allow safe passage and to sustain the migration ecology of the species. The distribution of the long-toed salamander overlaps extensively with the forestry industry, a dominant resource supporting the economy of British Columbia and the western United States. Long-toed salamanders will alter migration behaviour and are affected negatively by forestry practices not offering sizable management buffers and protections for the smaller wetlands where salamanders breed. Populations near the Peace River Valley, Alberta, have been lost to the clearing and draining of wetlands for agriculture. Trout introduced for the sport fisheries into once fishless lakes are also destroying long-toed salamander populations. Introduced goldfish predate upon the eggs and larvae of long-toed salamanders. Increased exposure to UVB radiation is another factor being implicated in the global decline of amphibians and the long-toed salamander is also susceptible to this threat, which increases the incidence of deformities and reduces their survival and growth rates.
The subspecies Ambystoma macrodactylum croceum (Santa Cruz Long-toed Salamander) is of particular concern and it was afforded protections in 1967 under the US Endangered Species Act. This subspecies lives in a narrow range of habitat in Santa Cruz County and Monterey County, California. Prior to receiving protections, some few remaining populations were threatened by development. The subspecies is ecologically unique, having unique and irregular skin patterns on its back, a unique moisture tolerance, and it is also an endemic that is geographically isolated from the rest of the species range. Other subspecies include A. m. columbianum, A. m. krausei, A. m. macrodactylum and A. m. sigillatum.
Systematics and Biogeography
The ancestral origins for this species stem from eastern North America, where species richness of ambystomatids are highest. The following biogeographic interpretation on the origins of A. macrodactylum into western North America is based on a descriptive account of fossils, genetics, and biogeography. The long-toed salamander's closest living sister species is A. laterale, a native to northeastern North America. Ambystomatidae was isolated to the southeast of the mid-Continental or Western Interior Seaway during the Cretaceous (~145.5–66 Ma). While three other species of the Ambystomatidae (A. tigrinum, A. californiense, and A. gracile) have overlapping ranges in western North America, the long-toed salamander's closest living sister species is A. laterale, a native to northeastern North America. It has been suggested that A. macrodactylum speciated from A. laterale after the Paleocene (~66–55.8 Ma) with the loss of the Western Interior Seaway opening an access route for a common ancestor into the Western Cordillera. Once situated in the montane regions of western North America, species had to contend with a dynamic spatial and compositional ecology responding to the changes in altitude, as mountains grew and the climate changed. For example, the Pacific Northwest became cooler in the Paleocene, paving the way for temperate forest to replace the warmer tropical forest of the Cretaceous. A scenario for the splitting of A. macrodacylum and other western temperate species from their eastern counterparts involves Rocky Mountain uplift in the late Oligocene into the Miocene. The orogeny created a climatic barrier by removing moisture from the westerly air stream and dried the midcontinental area, from southern Alberta to the Gulf of Mexico.
Ancestors of contemporary salamanders were likely able to disperse and migrate into habitats of the Rocky Mountains and surrounding areas by the Eocene. Mesic forests were established in western North America by the mid Eocene and attained their contemporary range distributions by the early Pliocene. The temperate forest valleys and montane environments of these time periods (Paleogene to Neogene) would have provided the physiographic and ecological features supporting analogs of contemporary Ambystoma macrodactylum habitats. The Cascade Range rose during the mid Pliocene and created a rain shadow effect causing the xerification of the Columbia Basin and also altered ranges of temperate mesic ecosystems at higher elevations. The rise of the Cascades causing the xerification of the Columbia Basin is a major biogeographic feature of western North America that divided many species, including A. macrodactylum, into coastal and inland lineages.
There are five subspecies of long-toed salamander. The subspecies are discerned by their geographic location and patterns in their dorsal stripe; Denzel Ferguson gives a biogeographic account of skin patterns, morphology; based on this analysis, he introduced two new subspecies: A. macrodactylum columbianum and A. m. sigillatum. The ranges of subspecies are illustrated in Robert Stebbin's amphibian field guides.
Physical appearance (phenotypes)
- A. m. croceum
- Orange dorsal color on tail breaking into patches along black body and into tiny dots on head, often absent anterior to eyes. Sides have whitish flecks. Number of costal grooves equals 13.
- A. m. columbianum
- Yellow to tan dorsal stripe on black body, continuous blotches to spots along body ending in narrowed blotches with spot patterns distributed on the head. White flecks along the sides and underside remaining as separate small flecks. Number of vomerine teeth greater than 35.
- A. m. krausei
- Yellow to tan dorsal stripe, continuous blotches to spots along body ending in widened blotches with spot patterns distributed on the head. White flecks along the sides and underside remaining as separate small flecks. Number of vomerine teeth equaling 32. Number of costal grooves equals 12.
- A. m. sigillatum
- Wax yellow to tan dorsal stripe forming spotty to irregular shaped blotches along body ending in dots or specks of dorsal color on head. Number of vomerine teeth equals 44. Number of costal grooves equals 13.
- A. m. macrodactylum
- Citrine, dull citrine, to tan dorsal stripe that is diffuse and continuous along grayish body. Pattern ending in diffuse specks of stripe color or absent on head and snout. White flecks on sides sometimes coming together to form larger flecks. Number of vomerine teeth equaling 33, forming a distinguished transverse arc. Number of costal grooves equals 13.
Biogeography and genetics
Mitochondrial DNA analysis identifies somewhat different ranges for the subspecies lineages. The genetic analysis, for example, identifies an additional pattern of deep divergence in the eastern part of the range. The spatial distribution of populations and genetics of this species links spatially and historically through the interconnecting mountain and temperate valley systems of western North America. The breeding fidelity of long-toed salamanders (philopatry) and other migratory behaviours reduce rates of dispersal among regions, such as within mountain basins. This aspect of their behavior restricts gene flow and increases the degree and rates of genetic differentiation. Genetic differentiation among regions is higher in the long-toed salamander than measured in most other vertebrate groups. Natural breaks in the range of dispersal and migration occur where ecosystems grade into drier xeric low-lands (such as prairie climates) and at frozen or harsher terrain at high elevation extremes (2,200 meters (7,200 ft)).
- A. m. columbianum
- Genetic evidence for the 'central' subspecies (A. m. columbianum) suggests that it does not extend north into British Columbia, but is restricted to the Blue and Wallowa Mountains of central to northeastern sections of Oregon. Populations are restricted to these areas by the Snake River Canyon (Idaho) to the east and low dry or xeric lands in the Madras basin to the west.
- A. m. macrodactylum
- The 'coastal' or 'western' subspecies (A. m. macrodactylum) lineage extends north from northeastern California, across the Klamath Siskiyou Range, through the Willamette Valley, along the coastal mountain ranges, including the Cascade Mountains, and continuing north through British Columbia and up into Alaska.
- A. m. croceum
- The Santa Cruz long-toed salamander (A. m. croceum) is most closely related to the 'coastal' or 'western' subspecies. This conclusion is the most parsimonious biogeographic explanation with nearest populations of A. m. macrodactylum separated by approximately 300 km across the Sacramento-San Joaquin River Delta, California. The isolated endemic populations are listed as an endangered subspecies. Based on the biogeography and molecular clock calibrations, this subspecies may have been separated from the remainder of the distribution since the Miocene, molecular clock calibrations estimating 13.9 million years of separation.
- A. m. krausei
- The 'eastern' subspecies (A. m. krausei) range is distributed throughout the interior mountains, with the western extent of its range encroaching into the low-land areas of the central interior plateau of Washington and British Columbia and the eastern extent of its range pushing through Rocky Mountain valleys into the lowland foothills and prairies of Montana and Alberta.
- A. m. sigillatum
- The traditional 'southern' subspecies (A. m. sigillatum) does not register a mitochondrial genetic identity. This subspecies was identified by Ferguson as forming an integrade with A. m. columbianum in south central Oregon.
Thompson and Russell found another evolutionary lineage that originates in a glacially restricted area of the Salmon River Mountains, Idaho. With the arrival of the Holocene interglacial, approximately 10,000 years ago, the Pleistocene glaciers receded and opened a migratory path linking these southern populations to northern areas where they currently overlap with A. m. krausei and co-migrated north into the Peace River (Canada) Valley. Ferguson also noted an intergradation in the same geographic area, but between the morphological subspecies A. m. columbianum and A. m. kraisei that run parallel to the Bitteroot and Selkirk ranges. Thompson and Russell suggest that this contact zone is between two different subspecies lineages because the A. m. columbianum lineage is geographically isolated and restricted to the central Oregon Mountains.
- Santa Cruz Long-toed Salamander, an endangered subspecies
- Originally described as Ambystoma macrodactyla.
- Tihen J (1958). "Comments on the osteology and phylogeny of ambystomatid salamanders". Bulletin Florida State Museum 3 (1): 1–50. Retrieved 2010-01-11.
- Jones TR, Kluge AG, Wolf AJ (1993). "When theories and methodologies clash: A phylogenetic reanalysis of the north American ambystomatid salamanders (Caudata: Amybstomatidae)". Systematic Biology 42 (1): 92–102. doi:10.1093/sysbio/42.1.92.
- Wiens JJ (2007). "Global patterns of diversification and species richness in amphibians". American Naturalist 170 (S2): S86–S106. doi:10.1086/519396. PMID 17874387.
- Zhang P, Wake DB (2009). "Higher-level salamander relationships and divergence dates inferred from complete mitochondrial genomes" (PDF). Molecular Phylogenetics and Evolution 53 (2): 492–508. doi:10.1016/j.ympev.2009.07.010. PMID 19595776.
- Larson A (1996). "Ambystomatidae". Tree of Life Web Project. Retrieved 2010-01-14.
- Stebbins RA (2003). A Field Guide to Western Reptiles and Amphibians (Peterson Field Guide Series) (3rd ed.). Boston: Houghton Mifflin. ISBN 0-395-98272-3.
- Thoms C, Corkran CC (2006). Amphibians of Oregon, Washington And British Columbia: A Field Identification Guide (Lone Pine Field Guides). Edmonton, Alberta, Canada: Lone Pine Publishing. ISBN 1-55105-566-X.
- Salthe SN (1963). "The egg capsules in the amphibia". Journal of Morphology 113 (2): 161–171. doi:10.1002/jmor.1051130204. PMID 14065317.
- Watson S, Russell AP (2000). "A posthatching developmental staging table for the Long-toed salamander, Ambystoma macrodactylum krausei" (PDF). Amphibia-Reptilia 21 (2): 143–154. doi:10.1163/156853800507336. Retrieved 2010-01-14.
- Parichy DM (1996). "Pigment patterns of larval salamanders (Ambystomatidae, Salamandridae): the role of the lateral line sensory system and the evolution of pattern-forming mechanisms" (PDF). Developmental Biology 175 (2): 265–282. doi:10.1006/dbio.1996.0114. PMID 8626032.
- Pederzoli A, Gambarelli A, Restani C (2003). "Xanthophore migration from the dermis to the epidermis and dermal remodeling during Salamandra salamandra salamandra (L.) larval development". Pigment Cell Research 16 (1): 50–58. doi:10.1034/j.1600-0749.2003.00013.x. PMID 12519125.
- Ferguson DE (1961). "The geographic variation of Ambystoma macrodactylum Baird, with the description of two new subspecies". The American Midland Naturalist 65 (2): 311–338. doi:10.2307/2422958. JSTOR 2422958.
- Watson, Sheri M (1997). Food level effects on metamorphic timing in the long-toed salamander, Ambystoma macrodactylum krausei (MSc thesis). University of Calgary. ISBN 978-0-612-20859-9. OCLC 150699685.
- Baird SF (1849). "Revision of the North American Tailed-Batrachia, with descriptions of new genera and species—Description of four new species of North America Salamanders, and one new species of Scink". Journal of the Academy of Natural Sciences of Philadelphia 1 (4): 281–292.
- Petranka JW (1998). Salamanders of the United States and Canada. Washington, D.C: Smithsonian Books. ISBN 1-56098-828-2.
- Graham KL, Powell GL (1999). Status of the Long-toed Salamander (Ambystoma macrodactylum) in Alberta. Alberta Environmental Protection, Fisheries and Wildlife Management Division, and Alberta Conservation Association, Wildlife Status Report No. 22. Edmonton, Alberta, Canada: Alberta Environmental Protection, Fisheries and Wildlife Management Division, and Alberta Conservation Association. p. 1. Retrieved 2010-01-15.
- Howard JH, Wallace RL (1985). "Life history characteristics of populations of the longtoed salamander (Ambystoma macrodactylum) from different altitudes". American Midland Naturalist 133 (2): 361–373. JSTOR 2425582.
- Funk WC, Dunlap WW (1999). "Colonization of high-elevation lakes by long-toed salamanders (Ambystoma macrodactylum) after the extinction of introduced trout populations". Canadian Journal of Zoology 77 (11): 1759–1767. doi:10.1139/cjz-77-11-1759.
- Giordano AR, Ridenhour BJ, Storfer A (April 2007). "The influence of altitude and topography on genetic structure in the long-toed salamander (Ambystoma macrodactulym)". Molecular Ecology 16 (8): 1625–1637. doi:10.1111/j.1365-294X.2006.03223.x. PMID 17402978. Retrieved 2010-01-14.
- Russell RW, Anderson JD (1956). "A disjunct population of the long-toed salamander from the coast of California". Herpetologica 12: 137–140.
- Carl CG (1943). The Amphibians of British Columbia. Handbook No. 2 (3rd ed.). Victoria, BC: British Columbia Provincial Museum, Department of Education.
- Nussbaum RA, Brodie ED Jr., Storm RM. (1983). Amphibians and reptiles of the Pacific northwest. Moscow, Idaho: University Press of Idaho. ISBN 0-89301-086-3.
- For Alaskan distributions, see MacDonald SO. Amphibians and Reptiles of Alaska. See also: Norman BR. (1999). "Geographic distribution: Ambystoma macrodactylum". Herpetological Review 30:171.
- Green DM, Campbell RW. (1992). The Amphibians of British Columbia. Royal British Columbia Museum Handbook No. 45. Province of British Columbia, Ministry of Tourism and Ministry Responsible for Culture.
- Thompson MD. (2001). An unusually adept Ambystomatid, the long-toed salamander, coping at northern extremes. The Boreal Dip Net 5(2): 8–10. PDF
- Verrell P (2007). "The female reproductive cycle of the North American salamander Ambystoma macrodactylum columbianum". Amphibia-Reptilia 27 (2): 274–277. doi:10.1163/156853806777239887.
- Trueb L, Duellman WE (1994). Biology of Amphibians. Baltimore: Johns Hopkins University Press. p. 112. ISBN 0-8018-4780-X. Retrieved 2010-03-06.
- Regester KJ, Whiles MR (2006). Taylor, C. M., ed. "Decomposition rates of salamander (Ambystoma maculatum) life stages and associated energy and nutrient fluxes in ponds and adjacent forest in southern Illinois". Copeia 2006 (4): 640–649. doi:10.1643/0045-8511(2006)6[640:DROSAM]2.0.CO;2. JSTOR 4126531.
- Petrisko JE, Pearl CA, Pilliod DS, Sheridan PP, Williams CF, Peterson CR, Bury BR (2008). "Saprolegniaceae identified on amphibian eggs throughout the Pacific Northwest, USA, by internal transcribed spacer sequences and phylogenetic analysis" (PDF). Mycologia 100 (2): 171–180. doi:10.3852/mycologia.100.2.171. PMID 18592894. Retrieved 2010-03-07.
- Anderson JD (1968). "A Comparison of the Food Habits of Ambystoma macrodactylum sigillatum, Ambystoma macrodactylum croceum and Ambystoma tigrinum californiense". Herpetologica 24 (4): 273–284. JSTOR 3891365.
- Walls SC, Belanger SS, Blaustein AR (1993). "Morphological variation in a larval salamander: dietary induction of plasticity in head shape". Oecologia 96 (2): 162–168. doi:10.1007/BF00317728.
- Kezer J, Farner DS (1955). "Life History Patterns of the Salamander Ambystoma macrodactylum in the High Cascade Mountains of Southern Oregon". Copeia 1955 (2): 127–131. doi:10.2307/1439318. JSTOR 1439318.
- Marnell LF (1997). "Herpetofauna of Glacier National Park". Northwestern Naturalist 78 (1): 17–33. doi:10.2307/3536855. JSTOR 3536855.
- Howard JH, Wallace RL (1981). "Microgeographic variation of electrophoretic loci in populations of Ambystoma macrodactylum columbianum (Caudata: Ambystomatidae)". Copeia (2): 466–471.
- Gregory PT, Matsuda BM, Green D (2006). Amphibians and Reptiles of British Columbia. Victoria: Royal BC Museum. ISBN 0-7726-5448-4.
- Russell AP, Powell GL, Hall DR (1996). "Growth and age of Alberta long-toed salamanders (Ambystoma macrodactylum krausei): a comparison of two methods of estimation". Canadian Journal of Zoology 74 (3): 397–412. doi:10.1139/z96-047. Retrieved 2010-03-07.
- Adding to the range of weight and sizes come from the NAMOS BC amphibian database .
- Kezer J, Farner DS (1955). "Life history patterns of the salamander Ambystoma macrodactylum in the high Cascade Mountains of southern Oregon". Copeia 1955 (2): 127–131. doi:10.2307/1439318. JSTOR 1439318.
- Slater JR (1936). "Notes on Ambystoma gracile Baird and Ambystoma macrodactylum Baird". Copeia 1936 (4): 234–236. doi:10.2307/1436330. JSTOR 1436330.
- Verrell P, Pelton J (1996). "The sexual strategy of the central long-toed salamander, Ambystoma macrodactylum columbianum, in southeastern Washington". Journal of Zoology 240: 37–50. doi:10.1111/j.1469-7998.1996.tb05484.x.
- Fukumoto JM. (1995). Long-toed salamander (Ambystoma macrodactylum) ecology and management in Waterton Lakes National Park (ME thesis). University of Calgary. ISBN 978-0-612-04397-8. OCLC 70487881.
- Thompson, Mark D (2003). Phylogeography of the long-toed salamander, Ambystoma macrodactylum (MSc thesis). University of Calgary. ISBN 978-0-612-87451-0. OCLC 150649401.
- Beneski J Jr, Zalisko EJ, Larsen J Jr (1986). "Demography and migratory patterns of the eastern long-toed salamander, Ambystoma macrodactylum columbianum". Copeia 2 (2): 398–408. JSTOR 1444998.
- Stebbins RC, Cohen NW. (1995). A Natural History of Amphibians. Princeton University Press ISBN 0-691-10251-1.
- Knudsen JW (1960). "The courtship and egg mass of Ambystoma gracile and Ambystoma macrodactylum". Copeia 1: 44–46. doi:10.2307/1439844.
- Anderson JD (1961). "The Courtship Behavior of Ambystoma macrodactylum croceum". Copeia 1961 (2): 132–139. doi:10.2307/1439987. JSTOR 1439987.
- Sheppard, Robert Frank (1997). The ecology and home range movements of Ambystoma macrodactylum krausei (Amphibia:Urodela) (M. Sc thesis). University of Calgary. OCLC 15847219.
- Williams, Thomas A; Larsen, John H (1986). "New function for the granular skin glands of the eastern long-toed salamander,Ambystoma macrodactylum columbianum". Journal of Experimental Zoology 239 (3): 329. doi:10.1002/jez.1402390304.
- Grant JB, Evans JA (2007). "A technique to collect and assay adhesive-free skin secretions from Ambystomatid salamanders". Herpetological Review 38 (3): 301–5.
- Toledo, R (1995). "Cutaneous granular glands and amphibian venoms". Comparative Biochemistry and Physiology Part A: Physiology 111: 1. doi:10.1016/0300-9629(95)98515-I.
- "NAMOS BC (Northern Amphibian Monitoring Outpost Society)". Retrieved 2009-06-24.
- Odelberg SJ (2005). "Cellular plasticity in vertebrate regeneration". Anatomical Record. Part B, New Anatomist 287 (1): 25–35. doi:10.1002/ar.b.20080. PMID 16308861.
- Lannoo MJ. (2005). Amphibian Declines: The Conservation Status of United States Species. University of California Press.
- Blaustein AR, Kiesecker JM. (2002). Complexity in conservation: lessons from the global decline of amphibian populations. Ecology Letters 5: 597–608. PDF
- Luck GW, Daily GC, Ehrlich PR. (2003). Population diversity and ecosystem services. Trends in Ecology and Evolution 18(7): 331–336. PDF
- Gascon C, Collins JP, Moore RD, Church DR, McKay JE, Mendelson JR III. (eds). (2007). Amphibian Conservation Action Plan. IUCN/SSC Amphibian Specialist Group. Gland, Switzerland and Cambridge, UK. 64 pp. PDF
- Wood CW, Gross MR. (2008). Elemental Conservation Units: Communicating Extinction Risk without Dictating Targets for Protection. Conservation Biology 22(1): 36–47. PDF
- Kareiva P, Marvier M. (2003). Conserving biodiversity coldspots. American Scientist 91: 344–351. PDF
- Davic RD, Welsh HH Jr. (2004). On the ecological role of salamanders. Annual Review of Ecology and Systematics 35: 405–434. PDF
- Whiles, M.R.; Lips, K.R.; Pringle, C.M.; Kilham, S.S.; Bixby, R.J.; Brenes, R.; Connelly, S.; et al. "The effects of amphibian population declines on the structure and function of Neotropical stream ecosystems". Frontiers in Ecology (1): 27–34.
- John, Fraley (October 2009). Long-toed Salamander. Montana Outdoors. ISBN 0-7785-2002-1.
- Collins, J.P.; Crump, M. (2008). Extinction in our times: Global amphibian decline. New York: Oxford University Press. ISBN 0-19-531694-0.
- Beebee, T.J.C.; Griffiths, R (2005). "The amphibian decline crisis: A watershed for conservation biology?". Biological Conservation 125 (3): 271–285. doi:10.1016/j.biocon.2005.04.009.
- Becker CG, Fonseca CR, Haddad CFB, Batista RF, Prado PI. (2007). Habitat Split and the Global Decline of Amphibians. Science 318(5857): 1775–1777.
- Ferguson C. (1999). Impacts of forest harvesting on the long-toed salamander (Ambystoma macrodactylum) at Opax Mountain. Pp. 221–229 In C. Hollstedt, A. Vyse, and D. Huggard, eds. New information for the management of dry Douglas-fir forests: Proc. dry Douglas-fir workshop. B.C. Minist. for., Victoria, BC. PDF
- Naughton GP, Henderson CB, Foresman KR, McGraw RL II. (2000). Long-toed salamanders in harvested and intact Douglas-fir forests of western Montana. Ecological Applications 10(6): 1681–1689.
- Walsh R. (1998). An extension of the known range of the long-toed salamander, Ambystoma macrodactylum, in Alberta. Canadian Field Naturalist 112: 331–333.
- Funk WC, Dunlap WW. (1999). Colonization of high-elevation lakes by long-toed salamanders (Ambystoma macrodactylum) after the extinction of introduced trout populations. Canadian Journal of Zoology 77: 1759–1767.PDF
- Monello RJ, Wright RG. (2001). Predation by goldfish (Carassius auratus) on eggs and larvae of the eastern Long-Toed Salamander (Ambystoma macrodactylum columbianum). Journal of Herpetology 35(2): 350–353.
- Blaustein AR, Kiesecker JM, Chivers DP, Anthony RG. (1997). Ambient UV-B radiation causes deformities in amphibian embryos. Proceedings of the National Academy of Sciences of the United States of America 94(25): 13735–13737.
- Belden LK, Wildy EL, Blaustein AR. (2000). Growth, survival, and behaviour of larval long-toed salamanders (Ambystoma macrodactylum) exposed to ambient levels of UV-B radiation. Journal of Zoology (London) 251: 473–479.
- Croteau MC, Davidson MA, Lean DR, Trudeau VL. (2008). Global increases in ultraviolet B radiation: potential impacts on amphibian development and metamorphosis. Physiological and Biochemical Zoology 81(6): 743–761. PDF
- "DFG - Nongame Wildlife Program - Threatened and Endangered Amphibians". Retrieved 2009-06-23.
- Anderson JD. (1972). Behavior of three subspecies of Ambystoma macrodactylum in a soil moisture gradient. Journal of Herpetology 6(3–4): 191–194.
- Reed RJ. (1978). Population study of the Santa Cruz long-toed salamander (Ambystoma macrodactylum croceum) at Valencia Lagoon 1977–1978, with notes on habitat and occurrence in Santa Cruz and Monterey counties. Calif. Dept. Fish & Game, contract S-1180.
- Fisher RN, Shaffer HB. (2002). The Decline of Amphibians in California's Great Central Valley. Conservation Biology 10(5): 1387–1397.
- Milner AR (1983). "The biogeography of salamanders in the mesozoic and early caenozoic: A cladistic-vicariance model.". In Sims RW, Price JH, Whalley PES. Evolution, Time and Space: The Emergence of the Biosphere. The Systematics Association special volume 23. London: Academic Press. pp. 431–468. ISBN 0-12-644550-8.
- Duellman EW (1999). Patterns of Distribution of Amphibians: A Global Perspective. JHU Press. p. 633. ISBN 978-0-8018-6115-4. Retrieved 2010-01-12.
- Thompson MD, Russell AP (2005). "Glacial Retreat and its Influence on Migration of Mitochondrial Genes in the Long-toed Salamander (Ambystoma macrodactylum) in Western North America". In Elewa AMT. Climatology, Geography, Ecology: Causes of Migration in Organisms. Heidelberg, Germany: Springer-Verlag Publishers. pp. 205–246. ISBN 978-3-540-26603-7.
- Milner AR. (1983). The biogeography of salamanders in the mesozoic and early Caenozoic: A cladistic-vicariance model. In Sims, RW, Price JH, Whalley PES. (Eds.), Evolution, Time and Space: The Emergence of the Biosphere. (pp. 431–468) Vol. 23 of The Systematics Association, Special Volume. Academic Press, London.
- Nussbaum RA. (1974). Geographic Variation and Systematics of Salamanders of the Genus Dicamptodon Strauch (Ambystomatidae). 94 pp. Miscellaneous Publications of the Museum of Zoology, University of Michigan, No. 149.
- Daubenmire R (March 1975). "Floristic Plant Geography of Eastern Washington and Northern Idaho". Journal of Biogeography 2 (1): 1–18. doi:10.2307/3038197. JSTOR 3038197.
- For the original source describing the paleoenvironmental analogs that was cited by Thompson (2003), see: Heusser C, Minneapolis (1983). Vegetational history of the Northwestern United States including Alaska: The late Pleistocene. In: Wright H, Porter S. (Eds.). Late-Quaternary Environments of the United States. (pp. 239–258) University of Minnesota Press.
- Brunsfeld S, Sullivan J, Soltis D, Soltis P. (2001). Comparative phylogeography of northwestern North America: A synthesis. In: Silverton, J., Antonovics, J. (Eds.), Integrating Ecology and Evolution in a Spatial Context. The 14th Special Symposium of the British Ecological Society. British Ecological Society, Blackwell Science Ltd., Ch. 15, pp. 319–339.
- Steele, C. A; Carstens, B. C.; Storfer, A.; Sullivan, J. (2005). "Testing hypotheses of speciation timing in Dicamptodon copei and Dicamptodon aterrimus (Caudata: Dicamptodontidae)". Molecular Phylogenetics and Evolution 36 (1): 90–100. doi:10.1016/j.ympev.2004.12.001. PMID 15904859.
- Tallmon DA, Funk WC, Dunlap WW, Allendorf FW (2000). McEachran, J. D., ed. "Genetic differentiation among long-toed salamander (Ambystoma macrodactylum) populations". Copeia 2000 (1): 27–35. doi:10.1643/0045-8511(2000)2000[0027:GDALTS]2.0.CO;2. JSTOR 1448236.
- The height of elevation extremes varies with climate, but >2,200 metres (7,200 ft) is likely to be an impediment to dispersal across most of this species range north of Oregon. See also: Giordano AR, Ridenhour BJ, Storfer A. (2008). The influence of altitude and topography on genetic structure in the long-toed salamander (Ambystoma macrodactulym). Molecular Ecology 16(8): 1625–1637. PDF
Names and Taxonomy
Comments: For phylogenetic analyses of North American Ambystoma, see Kraus (1988), Shaffer et al. (1991), and Jones et al. (1993).
Five subspecies are currently recognized, one occurs in Alaska. It has been suggested that the mainland and island population in the vicinity of the Stikine River of coastal Alaska are phenotypically and taxonomically distinct (MacDonald 2003).