|Scientific Name:||Urolophus javanicus (Martens, 1864)|
|Taxonomic Notes:||Only known from the type specimen. A good species but extended variation unknown.|
|Red List Category & Criteria:||Critically Endangered (Possibly Extinct) B1ab(iii,v) ver 3.1|
|Assessor(s):||Last, P.R. & Marshall, L.J.|
|Reviewer(s):||Kyne, P.M., Fowler, S.L. & Compagno, L.J.V. (Shark Red List Authority)|
Recorded from off Java, Indonesia, Urolophus javanicus is only known from the type specimen and has not been recorded again since its discovery 150 years ago. Possibly extinct, on the verge of extinction or at least has suffered extreme range restriction and/or population declines. Extensive fishing, particularity in the form of trawling, in the region is of major concern regarding the conservation of the species. Similarly the type locality is near major human population centres and has suffered high levels of degradation over the last century. This species may have been captured in the past but without being recognised. It would be retained and landed if captured by artisanal or commercial fisheries. If the population of this species remained healthy it should have resurfaced particularly given the various surveys conducted in the region. There are ongoing market surveys around Java, and there is an urgent need to re-survey the region to define population remnants (if they exist) and introduce appropriate management where possible. Given the restricted extent of occurrence with the species known from only one location, the species is assessed as Critically Endangered inferring a continuing decline in habitat quality through pollution and degradation and a continuing decline in the number of mature individuals through intensive fishing pressure in the region.
|Date last seen:||mid 19th century|
|Range Description:||Known only from off Java (probably near Jakarta), Indonesia. Actual range is unspecified but certainly very restricted and has possibly reduced due to intensive fishing pressure.|
Possibly extinct:Indonesia (Jawa)
|FAO Marine Fishing Areas:|
Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Unknown but as known only from the type specimen in an area that is heavily fished and despite survey work, has not been recognized in 150 years, this species is likely very rare.|
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||Biology unknown. The holotype is a 33.3 cm TL female. Likely to have low fecundity (1 to 2 young/year) as with other urolophid species (for example see White et al. 2001). |
Life history parameters
Age at maturity (years): Unknown.
Size at maturity (total length): At least 33 cm TL.
Longevity (years): Unknown.
Maximum size (total length cm): Unknown.
Size at birth (cm): Unknown.
Average reproductive age (years): Unknown.
Gestation time (months): Unknown.
Reproductive periodicity: Unknown.
Average annual fecundity or litter size: Unknown.
Annual rate of population increase: Unknown.
Natural mortality: Unknown.
|Major Threat(s):||Not recognized since its discovery over 150 years ago and possibly extinct, on the verge of extinction or at least has suffered extreme range restriction and/or population decline. Extensive fishing, particularity in the form of trawling, in the region is of major concern regarding the conservation of the species. Similarly the type locality is near major human population centres and has suffered high levels of degradation over the last century. May have been captured in the past but without being recognised. If the population of this species remained healthy it should have resurfaced particularly given the various surveys conducted in the region.|
|Conservation Actions:||There are ongoing market surveys around Java and there is an urgent need to re-survey the region to define population remnants and introduce appropriate management where possible. Given locality of species, management and enforcement of any regulations will be difficult.|
|Citation:||Last, P.R. & Marshall, L.J. 2006. Urolophus javanicus. The IUCN Red List of Threatened Species 2006: e.T60095A12247760.Downloaded on 25 April 2018.|