|Scientific Name:||Narcine nelsoni|
|Species Authority:||Carvalho, 2008|
|Taxonomic Notes:||The Eastern Numbfish (Narcine nelsoni) is a recently described species (Carvalho 2008).|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Reviewer(s):||Ebert, D.A. & Kyne, P.M.|
The Eastern Numbfish (Narcine nelsoni) is a small numbfish that is endemic to northeastern Australia. This species has a distribution restricted to an area off central Queensland and occurs in depths of 140–540 m. To date it has been recorded in only two areas, though many specimens have been collected together and it is expected to occur in relative abundance between these two distributional areas. Little is known of its biology and population trends. It is not likely to be of commercial value and threats are currently minimal as there is low fishing effort in the area of its occurrence. Future increases in fishing pressure within its range may pose a risk due to the restricted geographic range, however Australian fisheries are relatively well managed with ongoing ecological risk assessments conducted that take biological factors into account and give an indication of which species are at high risk from fishing in each fishery. Under this process, any changes in fishing activity and effort would be considered which should reduce the level of any potential future risks to species such as this numbfish. Despite this species being poorly known, there presently are no apparent considerable threats to the population, so the status of Least Concern is warranted.
The Eastern Numbfish is endemic to northeastern Australia in the Western Central Pacific with a distribution restricted to off the Queensland coast, from Dunk Island to Rockhampton. This species has been collected in two main areas: east of Dunk Island and further south off Swain and Saumarez Reefs and has not yet been recorded in between these two areas, though it is expected to occur in relative abundance between these two distributional locations (Carvalho 2008, Last and Stevens 2009).
|FAO Marine Fishing Areas:||
Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
In the areas from which the Eastern Numbfish has been recorded, many specimens have been collected together (Carvalho 2008). There is no other information about the population trends or structure.
|Habitat and Ecology:||
The Eastern Numbfish is demersal on the outer continental shelf and upper slope and has been recorded mainly in depths of 140–540 m Little is known of its biology; it reaches at least 35 cm total length (TL) with both sexes maturing at 20–25 cm TL (Carvalho 2008, Last and Stevens 2009).
|Use and Trade:||The Eastern Numbfish is not known to be utilized commercially (Carvalho et al. 1999).|
The main threat that may affect the Eastern Numbfish is fishing which has the potential to cause direct and indirect mortality and habitat modification. However, the current demersal fishing pressure across this species’ range is generally very low. The area of the Australian Commonwealth managed Coral Sea Fishery lies mostly to the east of the distribution of the Eastern Numbfish, overlapping only marginally with the species’ range. It is possible but unlikely that this numbfish is taken as bycatch in the Line and Trap Sector, and Trawl and Trap Sector of this fishery. While line, trawl and trap gear could capture this species as it fishes at depths this species occurs, they are relatively small-scale fisheries with effort less than seven vessels across both sectors in recent years and with no trawl fishing effort over the last two years (Furlani et al. 2007a,b; Woodhams et al. 2010). The management area of the fishery is far greater than the range of the Eastern Numbfish, with the majority of fishing effort outside of the species’ occurrence.
The Queensland managed Deep Water Fin Fish Fishery operates in all Queensland east coast waters east of the 200 m bathymetric line and does overlap this species’ distribution. However, this fishery uses benthopelagic rather than truly demersal gear, and most of the fishing effort, which is low with only four active licences, is in areas where the 200 m depth contour is relatively close to the coast. In recent years, the majority of the effort has been much further south than the range of this numbfish (DEEDI 2009). The deepwater eastern king prawn sector of the Queensland managed East Coast Trawl Fishery that operates to depths of 300–350 m could possibly take this species as bycatch at the southern limit of its distribution, though the majority of effort in this fishery sector is further south (Courtney and Posser 2009). This species has not been recorded in the commercial and research surveys of the bycatch of this fishery sector (Courtney et al. 2007).
There are no conservation actions currently in place for the Eastern Numbfish. Research is needed on its life history characteristics and further survey work would be beneficial to confirm the occurrence of this species’ in the full distributional range.
The Australian Commonwealth Government recognize that the line and trawl sectors of the Coral Sea Fishery (CSF) may pose a risk to chondrichthyans that occur deeper than 200 m. Though catches of chondrichthyans are extremely low and infrequent in the CSF, the Australian Fisheries Management Authority has taken a precautionary and proactive approach in recognition that they may be more susceptible than others to overfishing due to their low rates of reproduction. All deepwater sharks brought aboard live must be released alive, while a very small quantity of any dead animals may be retained by way of trip limits introduced in July 2010 to facilitate the collection of information on species occurrence. These trip limits do not currently include skates and rays as these are incidental to the catch and are released (AFMA 2010).
|Citation:||Rigby, C. 2011. Narcine nelsoni. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 08 July 2015.|