Species Details

Details of Spotted eagle ray will be displayed below

Spotted eagle ray   

Common Name: Spotted eagle ray
Scientific Name: Aetobatus narinari
Local Name: vaifiya madi
Dhivehi Name: ވައިފިޔަ މަޑި
Animalia  (Kingdom)
Chordata  (Plylum)
Rajiformes  (Order)
Myliobatidae  (Family)
Aetobatus   (Genus)

Spotted eagle ray's description

White-spotted eagle ray, grow to at least 3.5m disc width and 9m total length. The spotted eagle ray has a long snout, flat and rounded like a duck\\\'s bill, a thick head, and a pectoral disc with sharply curved, angular corners, and no caudal fin; jaws usually with single row of flat, chevron-shaped teeth. Each tooth is a crescent-shaped plate joined into a band. They usually have numerous white spots on black or bluish disc; with white below. Long whip-like tail, with a long spine near the base, behind small dorsal fin.

Spotted eagle ray habitat

The Whitespotted Eagle Ray is benthopelagic over the continental shelf from the surface to 60 m depth (Last et al. 2016). It frequently enters lagoons and estuaries and is often associated with coral reef ecosystems (Ajemian et al. 2012, Bassos-Hull et al. 2014). It reaches a maximum size of approximately 230 cm disc width (DW); males mature at 127–129 cm DW and females mature at 134.9 cm DW (Tagliafico et al. 2012, Last et al. 2016). Reproduction is matrotrophic viviparous and litters of 1–5 pups, with an average of 3, are produced annually after a 12-month gestation and size-at-birth is estimated at 18–36 cm DW (Tagliafico et al. 2012, Last et al. 2016). Generation length is inferred from the slightly larger (300 cm DW) Spotted Eagle Ray (Aetobatus ocellatus) which has a generation length of 12 years (Kyne et al. 2016), and this was scaled down to 10 years to account for the smaller size of the Whitespotted Eagle Ray.

Spotted eagle ray threats

Whitespotted Eagle Rays occur in coastal inshore waters where fishing pressure is substantial through portions of the species' range, particularly in the Gulf of Mexico, Caribbean Sea, and Eastern Central and Southeast Atlantic Ocean along the coast of Africa. The species often enters estuarine waters where fishing pressure is high. The swimming behaviour of this species makes it susceptible to a range of fishing gear throughout the water column, especially inshore gillnet fisheries, which are intensive throughout most of its range. This species is taken in target artisanal gillnet fisheries and industrial shrimp trawl fisheries.

First, in the Northwest and Western Central Atlantic, artisanal directed fisheries for Whitespotted Eagle Ray are not well described throughout its range but are known to exist in Mexico (Cuevas-Zimbrón et al. 2011), Cuba (Cuba NPOA-Sharks 2015), and Venezuela (Tagliafico et al. 2012). In Caribbean Colombia, artisanal fisheries are widespread and lack management, and there is also a shallow-water shrimp trawl fishery for which stocks have collapsed; this ray is taken there using gillnet, longline, and trawl gears (P. Mejía-Falla and A. Navia unpubl. data 2018);. In Venezuela, commercial and artisanal fisheries are intense, they lack management, and have exhibited peaks in catches followed by declines, indicative of sequential overfishing (Mendoza 2015), and this species is targeted in artisanal fisheries there (Tagliafico et al. 2012). Declining annual catch rates have been demonstrated for fisheries in Mexico and Venezuela (Cuevas-Zimbrón et al. 2011, Tagliafico et al. 2012).

Second, in the Southwest Atlantic, artisanal fisheries are intense across much of coastal Atlantic South America, and there are largely unmanaged commercial trawl and longline fisheries in many areas. Groundfish fisheries on the Brazil-Guianas shelf were already fully over-exploited by 2000; these fisheries are multi-gear, multi-species, and multinational, with vessels crossing national maritime borders (Booth et al. 2001). Despite some areal closures and the implementation of a total allowable catch of target species, there is now a diminished effort and number of vessels in operation there (Diop et al. 2015). In northwestern Brazil, artisanal fisheries pressure is high and 44% of target stocks were likely to be overfished by the end of the 2000s (Vasconcellos et al. 2011). The combination of intense and unmanaged artisanal and commercial fishing in that area has led to the disappearance of several elasmobranch species in the region, including Largetooth Sawfish (Pristis pristis), Smalltooth Sawfish (Pristis pectinata), Daggernose Shark (Isogomphodon oxyrhynchus), and Smalltail Shark (Carcharhinus porosus) (Charvet and Faria 2014, Lessa et al. 2016, Reis-Filho et al. 2016, Santana et al. 2020). In northeastern and eastern Brazil, artisanal fisheries are intense, gillnetting is the predominant artisanal gear, fishers there report that stocks are overexploited, and other sharks have been depleted (Guebert-Bartholo et al. 2011, Reis-Filho et al. 2016). In southern Brazil, the trawl fishery began in the 1960s and entered a period of rapid expansion in the 1990s and 2000s, resulting in over 650 vessels fishing at depths of 20–1,000 m (Port et al. 2016). Artisanal fisheries are also intense, and 58% of stocks targeted by artisanal fishers are overexploited, half of those having collapsed (Vasconcellos et al. 2011).

Third, in the Eastern Central Atlantic, sharks and rays were already being exploited by semi-industrial fisheries in the 1950s (Walker et al. 2005). While these fisheries gradually collapsed, the demand for dried salted shark meat (for export to Ghana) and shark fins in the 1980s drove the development of artisanal targeted shark fishing across much of the region (Diop and Dossa 2011, CCLME 2016, Seto et al. 2017, Moore et al. 2019). Over the years, this has expanded into targeted shark and ray fisheries across many countries and is likely increasing fishing pressure on this species (Walker et al. 2005, Diop and Dossa 2011). Furthermore, this has led to population reductions of many species of sharks and rays including the local extinction of sawfishes (family Pristidae) from West African coastal waters and several species of wedgefishes from their northern range in Mauritania and Senegal (e.g., False Shark Ray (Rhynchorhina mauritaniensis) from the Parc National du Banc d’Arguin) (Walker et al. 2005, Kyne et al. 2020). Sharks and rays are still targeted in a number of countries with artisanal fishers using drift gillnets and demersal set gillnets with large mesh sizes (e.g., Mauritania, Nigeria, Ghana, Cameroon; M. Diop, I. Seidu, A. Tamo, and A.B. Williams unpubl. data 2020).

In general, fishing effort and the number of fishers has intensified in recent decades across most of the range of this species. For example, in West Africa, reports indicate that the diversity and average body size of many important commercial coastal, demersal, and pelagic fishery species have markedly declined with many stocks now considered to be overexploited (FAO 2000, Srinivasan et al. 2012, Polidoro et al. 2016, CCLME 2016). Trawl surveys carried out across the Gulf of Guinea from 1977 to 2000 showed a decline in fish biomass of approximately 50% (Brashares et al. 2004). Further, the total demersal biomass of inshore stocks is estimated to have declined by 75% since 1982 (Meissa and Gascuel 2015). The direct cause of decline for many of these stocks has been attributed to overcapacity within both the industrial and artisanal fisheries and destructive fishing practices (GCLME 2006, CCLME 2016). Overall, between 1950 and 2010, the total artisanal fishing effort increased by 10-fold with an estimated 252,000 unregulated artisanal and 3,300 industrial vessels (mostly distant water fleets from Europe and East Asia operating under ‘access agreements’ that take sharks and rays as bycatch) operating in this region by 2010 (Walker et al. 2005, Diop and Dossa 2011, Belhabib et al. 2018).

Given their naturally molluscan diet, negative interactions with shellfish farming are episodic and anecdotally reported in the Northwest Atlantic (McEachran and Carvalho 2002, M. Ajemian pers. obs. 2019). Confirmed interactions generally stem from molluscan culture operations in the Indo-Pacific such as have also been reported for conspecifics such as A. narutobiei in Japan (Yamaguchi et al. 2005). While never implemented for Whitespotted Eagle Ray in the United States of America (USA), predator culling programs have been considered for other myliobatid species in the USA, notably Bat Ray (Myliobatis californicus) off California (Gray et al. 1997) and Cownose Ray (Rhinoptera bonasus) in Chesapeake Bay and elsewhere in the USA (Grubbs et al. 2016).

Whitespotted Eagle Ray is a popular public aquarium species and is collected for the marine aquarium trade (Swider et al. 2017). Since this species routinely enters estuaries this species may also be threatened by pollution, dredging, and habitat loss.

Spotted eagle ray's status