The Shortjaw Bonefish occurs from Hawaii and French Polynesia to the Seychelles in the western Indian Ocean, north to southern Japan and south to Lord Howe Island, Australia. Its type locality is in the Red Sea (Bowen et al. 2008). Reflecting results in Colborn et al. (2001), the geographic range of A. glossodonta is likely representative of multiple species.
Habitat and Ecology
Larvae of A. glossodonta are morphologically indistinguishable from A. argentea (then listed as A. forsteri) (Friedlander et al. 2008). Mean larval stage is 56 days (Friedlander et al. 2008). Maximum age recorded is 11 years (Friedlander et al. 2008). Sex ratio varies widely across its distribution (1 to 1.25 in a study by Friedlander and 1–6.75 in another (Beets 2000). Although minimum size and age at maturity is not known, Albula sp. reared in the lab were sexually mature at two and three years of age (Pfeiler et al. 2000). Using equation number five of section 4.4 of the Guidelines for Using the IUCN Red List Categories and Criteria (IUCN Standards and Petitions Working Group 2008), if generation length = age of first reproduction + z*(length of the reproductive period), and age at first reproduction is estimated at 2.5 years, z is estimated to be 0.5 based on survivorship and relative fecundity with age, and the length of the reproductive period is estimated at 8.5 years, then generation length is estimated to be 4.5 years.
This species primarily feeds on crustaceans, including mantis shrimps and crab, also polychaetes, bivalves and amphipods (Friedlander 1997). Crustaceans comprised more than 50% of the diet in a Hawaiian study (Friedlander 1997).
Natural mortality from sharks is very high at Palmyra Atoll (Adams pers. comm. 2011). The maximum size for this species is 90 cm (SL) (Myers 1991).
Molecular Biology and Genetics
Barcode data: Albula glossodonta
Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.
See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
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Download FASTA File
Statistics of barcoding coverage: Albula glossodonta
Public Records: 3
Specimens with Barcodes: 6
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
This species is rare in Mauritius (Sato et al. 2008).
In Tarawa, there has been a dramatic increase in scale of effort and modernization of the fishing gears. In 1977, bonefish comprised 44.6% of the total catch; in 1992, they were 7.5% of the total catch. This decline (37.1% in 15 years) was a result of overfishing, as opposed to a change in fishing method and effort (Beets 2000). Spawning aggregations are often targeted (Beets 2000). A survey from the Fisheries Division of Kiribati conducted in 1995 shows that bonefish was the second-most common species caught, accounting for 7% of total catch. Gill nets caught 82% of the bonefish, with handlines providing the remainder (18%) of the catch (Friedlander et al. 2008). In Tarawa Lagoon, Kiribati, recent studies have demonstrated significant declines in abundance and average size of bonefish in the catch between 1977 and the late 1990s. The annual take of bonefish from Tarawa Lagoon is between 1,000,000 and 5,000,000 fish per year, but no stock assessment has been conducted (Friedlander et al. 2008). This species is probably the most abundant molluscivorous fish in the lagoon (Beets 2001). Comparison data from fished and protected locations at Palmyra Atoll show significant differences in population characteristics which may indicate that threats are expressed asymmetrically across its range (Adams pers. comm. 2011). Given fisheries characteristics throughout the region, we expect that in areas where bonefish are exposed to fishing effort that Tarawa serves as an example of what would likely occur in other areas throughout its range. In addition, the recreational fishery is not well-established in the Indo-Pacific, so there is little economic incentive for conservation. Therefore, we do not expect conservation to be occurring at present.
Like A. vulpes, A. glossodonta may be closely associated with mangroves and seagrasses and other shallow coastal habitats. Valiela et al. (2001) estimate that mangroves have decreased worldwide by 35%, at a rate of 2% per year. Using this estimate, mangroves have declined global by an estimated 27% over the last three generation lengths for A. glossodonta (13.5 years). Much of this species' distribution lies in the Indo-Pacific, where up to 14% of mangrove species are listed as threatened (Vulnerable, Endangered, or Critically Endangered) in some places (Polidoro et al. 2010). The Indo-Malay Philippine Archipelago is of particular concern, as it has one of the highest rates of mangrove loss globally, with an estimated 30% reduction in mangrove area since 1980 (FAO 2007). In the tropical Indo-Pacific, 12% of all seagrasses are currently threatened, and 20% of all seagrass species are experiencing declines. In the temperate North Pacific, the northern-most part of A. glossodonta's range, 22% of all seagrass species are threatened, and 44% are experiencing population declines (Short et al. 2011). Given the declines in these habitats, we infer that the extreme habitat loss in parts of its Pacific range will have similar negative consequences for population trajectories.
Given population declines of at least 30% over three generation lengths at Tarawa, significant habitat loss throughout much of its range, we estimate global decline to equal or exceed 30% over three generation lengths (13.5 years), with some substantially greater localized depletions in parts of the Indo-Pacific.
Heavy fishing pressure and degradation of habitats at Tarawa and Kiritimati Atolls have resulted in the loss of pre-spawning staging sites and spawning migration routes, which may be responsible for the observed declines in bonefish catches, average size, and sex ratios at these locations (Friedlander et al. 2008). There are declines in CPUE, mean length and weight of fish and also a change in sex ratio (Beets 2000). Sex ratio (F:M) was 0.71:1 in 1977 and in 1992–1993 it was recorded as 0.15:1. In 1977, mean length was 46.4 cm and mean weight was 1.3 kg. In 1992, mean length recorded was 37.6 cm and mean weight was 0.84 kg. There was a decrease in the smallest size of sexually mature individuals between the two time periods: in 1977 the smallest size of sexually mature males was 42.5 cm and 46.5 cm for females; in 1992 is was 32 cm for males and 35 cm for females. In addition, Beets (2000) conservatively estimates that the 30% of total catch was non-reproductive. In Tarawa, there has been a dramatic increase in scale of effort and modernization of the fishing gears. In 1977, bonefish comprised 44.6% of the total catch; in 1992, they comprised only 7.5% of the total catch. Spawning aggregations are often targeted (Beets 2000). The effects of catch-and-release fishing on this species are unclear.
Unrestrained growth of human populations in the coastal zones has also accelerated habitat destruction, water quality degradation, and disruption of prey species dynamics. Fishing and habitat loss and degradation may pose the most significant threats to this species. Disruptions to shallow coastal ecosystems such as seagrasses and mangroves due to climate change may pose significant future threats to this species, particularly in areas with accelerated rates of coastal development and urbanization.
The limited range of this species may also make it vulnerable to local threats, such as habitat loss (Friedlander et al. 2008). It has been noted that habitat alteration, fragmentation and loss may contribute to the decline in abundance of this species in Tarawa (Beets 2000). Bonefish are closely associated with mangroves,seagrasses and other shallow coastal habitats. Given the dramatic declines in these habitats (Mumby et al. 2004, Valiela et al. 2001, Polidoro et al. 2010, Orth et al. 2006, Short et al. 2011), we infer that comparable regional declines are likely throughout its range. Valiela et al. (2001) estimates that mangroves have decreased worldwide by 35%, at a rate of 2% per year. Since bonefish rely upon habitats of limited extent, they are especially susceptible to habitat loss and degradation, particularly due to climatic and anthropogenic influences. These habitats are often fragmented in nature, exacerbating this issue. As with other coastal species, fragmentation will likely have direct and indirect negative impacts on bonefish.
Relevance to Humans and Ecosystems
Albula glossodonta (roundjaw bonefish, shortjaw bonefish, Indo-Pacific bonefish, sharpjaw bonefish, or smallmouth bonefish) is a type of marine fish found in the Pacific Ocean. They grow up to 70 cm.
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