| Citation |
Manjaji Matsumoto, B.M., White, W.T., Fahmi & Gutteridge, A.N. 2016. Pateobatis fai. The IUCN Red List of Threatened Species 2016: e.T161615A104219816. https://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T161615A104219816.en. Accessed on 15 December 2021. |
Description |
JUSTIFICATION
This is an amended version of the 2015 assessment to accommodate the change in genus name from Himatura to Pateobatis.
The Pink Whipray (Pateobatis fai) has a wide, but poorly defined range throughout the Indo-West Pacific. It is frequently misidentified as P. jenkinsii, which can complicate species-specific catch data. It is taken as a utilised bycatch of tangle/gillnet, trawl net, and dropline fisheries throughout Southeast Asia and parts of the Indian Ocean. Inshore fishing pressure is intense throughout this species range in Southeast Asia and in parts of the Indian Ocean. It is caught in particularly high numbers in the target fishery for rhynchobatids operating in the Arafura Sea. Although no species-specific data are available, overall catches of sharks and rays are reported to be declining, with fishermen having to travel further to sustain catch levels. Given the continuation of high levels of exploitation throughout its range in Southeast Asia where the species is commonly caught in multiple types of fisheries, along with evidence for declines in catches of rays, the level of decline (>30% over the last three generations) and exploitation can be inferred from overall declines in fish catches in the region, as well as from habitat loss.
In Australia, the Pink Whipray is considered at minimal threat throughout its wide range as there is no information to suggest that this species has declined in this area. Fisheries in northern Australia are generally well managed and the introduction of turtle exclusion devices (TEDs) have significantly reduced the bycatch of large stingrays. There are also marine protected areas in this species range, and this species is common in parts of the Great Barrier Reef Marine Park. This large species may have limiting life history characteristics that would make it biologically susceptible to depletion in fisheries and therefore, efforts should be made to assess and monitor mortality in fisheries and population trends throughout its range. The Pink Whipray is assessed as Vulnerable globally based on inferred levels of decline and exploitation across a large part of its range, but is considered to be Least Concern in Australia.
RANGE DESCRIPTION
The Pink Whipray has a likely widespread, but poorly defined range in the Indian and Western Pacific Oceans from southern Africa to Micronesia (White et al. 2006, Last and Stevens 2009).
Indian Ocean: Western Indian Ocean: South Africa (Last and Compagno 1999); Suez, Egypt (R. Bonfil pers. comm). Eastern Indian Ocean: Andaman Sea (Kuiter and Debelius 1994); Maldives (Anderson and Hafiz 1997); Myanmar.
Pacific Ocean: Northwest Pacific: Ryukyu Islands (Yoshigou and Yoshino 1999).Western Central Pacific: South China Sea and Sulu Sea off Sabah (Fowler et al. 1999); Indonesia; Thailand; Viet Nam and north to Myanmar; northern tropical Australia (Ningaloo Reef, Western Australia to Stradbroke Island, Queensland) (Whittington and Last 1994, Last and Stevens 2009); Caroline Islands (Homma et al. 1994); Orangere Bay, Papua New Guinea (P. Kailola pers. comm.); Eiao, Marquesas Islands (J. Randall pers. comm.); Apia, Samoa (Jordan and Seale 1906, Manjaji 2004); Philippines; Micronesia.
DESCRIPTION
This species is common but not abundant in some areas in Indonesia, Malaysia, Philippines (M. Manjaji-Matsumoto, Famhi and B. Samiengo, pers. obs. 2007). It can be relatively common in reef sand adjacent areas along northern Australia, (W. White, pers. obs., 2007), including in areas of the Great Barrier Reef.
Globally, shark and ray landings have declined by at least 20% since 2003, but the Indo-Pacific is amongst the regions where this decline has been more severe (Dulvy et al. 2014). Catches of sharks and rays in Southeast Asia are very high but are declining and fishers are travelling much further from port in order to increase catches (Chen 1996). Net and trawl fisheries in Indonesia (especially the Java Sea) and elsewhere are very extensive and as a result, many shark and ray species are highly exploited and stocks of most species have declined by at least an order of magnitude (Blaber et al. 2009). Batoids are heavily exploited (White and Dharmadi 2007) and datasets from as early as 1963–1972 show the considerable decline in batoids in the Gulf of Thailand (Pauly 1979). Trawl and gill net fisheries are also moving further afield. For example, in Jakarta the gillnet fishery at Muara Baru travels to waters around Kalimantan due to the decline in local populations (W.T. White, unpubl. data). While species-specific data on long-term declines in elasmobranchs in the Southeast Asian region are lacking, declines of the Pink Whipray in Southeast Asia and elsewhere in the Indo-West Pacific are inferred given the widespread historical and continuing declines of demersal fisheries in this region (Stobutzki et al. 2006). Furthermore, the extensive loss and degradation of habitats such as coastal mangroves are another key threat to coastal and inshore species; Southeast Asia has seen an estimated 30% reduction in mangrove area since 1980 (FAO 2007, Polidoro et al. 2010).
HABITAT AND ECOLOGY
The Pink Whipray is found on soft substrates on the inner continental shelf, from the intertidal zone to at least 200 m depth (Last and Stevens 2009). Reproduction is viviparous with histotrophy (White et al. 2006). Males reach maturity at 108-122 cm disc width (DW), but size at maturity for females is unknown (White and Dharmadi 2007, Last and Stevens 2009). Maximum size is at least 186 cm DW and size at birth is reported at 30-55 cm DW (Manjaji 2004, White et al. 2006, Gutteridge 2012). Little is known of its biology. A generation length of 20 years can be estimated based on the Blackspotted Whipray (Himantura astra) (Jacobsen and Bennett 2011), but noting that the Blackspotted Whipray grows to a much smaller maximum size (80 cm disc width) than the Pink Whipray (186 cm DW).
Aggregations have been observed on atolls of the Great Barrier Reef and Ningaloo Reef (Last and Stevens 2009); it has been observed aggregating in groups of up to 25 individuals within sandy coral reef and inshore habitats (Vaudo and Heithaus 2009). Tracking data indicates that such aggregations are likely seasonal, with more frequent aggregations known during warmer months (Vaudo and Heithaus 2012). The species has also been observed "catching a ride" on other large bodied ray species (in Ningaloo Marine Park, Western Australia) (W. White, pers. obs., 2007).
THREATS
The inshore fishing pressure for the Pink Whipray is high throughout much of its range in Southeast Asia. In this area, most bycatch by commercial fisheries (especially trawlers) are landed and sold as food fish. In Indonesia, and probably throughout other areas of its range, this species is captured by demersal tangle net, bottom trawl, commercial gillnet and, to a lesser extent, longline fisheries (White et al. 2006).
The Pink Whipray and other stingrays are an important retained bycatch of the commercial gillnet fishery in Indonesia that targets rhynchobatid rays in the Arafura Sea (Last and Compagno 1999; W. White, pers. obs. 2007). Catches in inshore waters have declined and these vessels are having to travel farther to sustain catches; the rhynchobatid fisheries are very intensive in this region, thus the level of exploitation is extremely high.
Within Borneo, the species is an occasional capture in the demersal tangle net and bottom trawl fisheries (Last et al. 2010), and it has been observed from fish market surveys within Thailand (Krajangdara 2014). Given that this species occurs in shallow, nearshore environments, ongoing and widespread degradation of coral reefs and coastal areas throughout south-east Asia are likely contributing to declines in the region.
In Sabah (Malaysia), Papua New Guinea, and Indonesia, Himantura species are often caught and landed in the inshore fisheries (trawls and longlines) and are also taken by Danish seine fishing gear (M. Manjaji-Matsumoto and Fahmi, pers. obs. 2007; W. White, pers. obs. 2014).
Within the prawn trawl fleet that operates in the Gulf of Papua in Southern Papua New Guinea, the Pink Whipray is captured in low numbers, as bycatch reduction gear are not currently in place for the fishery (L. Baje, pers. comm. 2015).
In Australia, catch data for this species is relatively limited, though large specimens were previously reported as bycatch in the Australian Northern Prawn Fishery. However, with the introduction of turtle exclusion devices (TEDs) and other bycatch reduction devices in the fishery, the ray bycatch has declined by 36.6% and there has been significant reductions in the catch and associated mortality of the Pink Whipray (Brewer et al. 2006).
This species may be more vulnerable to depletion given its large size at maturity and maximum size compared to other Himantura species (Manjaji-Matsumoto and Fahmi, pers. obs. 2007).
USE AND TRADE
The Pink Whipray is predominantly captured as bycatch throughout its range, but retained for its meat, highly valued skin, and cartilage in parts of Southeast Asia (Last and Compagno 1999, Last and Stevens 2009, Last et al. 2010).
CONSERVATION ACTIONS
The conservation measures in place for the Pink Whipray include both protected areas and gear modifications in fisheries.
In Australia, the use of TEDs in the Northern Prawn Fishery has been compulsory since 2000 (Day 2000) and following their introduction, ray bycatch has reduced by 36.3% (Brewer et al. 2006). The presence of marine protected areas within Australian coastal waters, such as Great Barrier Reef Marine Park (GBRMP) and Shark Bay Marine Reserve, has reduced the potential for this species to be captured, and it is very common in parts of the GBRMP.
In the Maldives, 15 popular dive sites were declared marine protected areas in 1995 with further protective measures under consideration (Anderson and Hafiz 1997). The Pink Whipray is one of the species that is fed daily at a popular dive site. The Maldives recognised the large economic value in terms of tourism that ray-watching brought and banned all exports of rays in June 1995 (Anderson and Hafiz 1997). |
