Increased anthropogenic activity in coastal regions results in species’ heightened exposure to boat traffic and strikes, mooring lines, and fishing activities, marine debris and storm water runoff. Manta rays can be disturbed by divers’ poor buoyancy or divers approaching too close to the station, which in turn, can also cause damage to the fragile coral ecosystem.Ĭritical juvenile habitats (often shallow, more protected areas of the reef) are vulnerable to anthropogenic pressures, including pollution and habitat or coastal erosion. An illegal market has been also identified mostly to export manta and mobula parts to Asian markets.Īside from their consumptive use in the gill plate trade and as meat (for bait and local consumption), manta rays are the focus of highly lucrative ecotourism “swim-with” experiences. Mantas that use to be considered bycatch are now kept and processed. The demand for this species has grown in recent years. The greatest threat facing all mobulid species are fisheries, either as targets or bycatch. Being a mobile, pelagic species that is often observed feeding near the surface mantas are highly susceptible to direct and by-catch fishing incidents. M. birostris is considered highly susceptible to anthropogenic threats. Giant manta ray (Manta birostris) geographic range©IUCN red list When National Marine Fisheries Service examined all the available scientific and commercial information for a critical habitat designation for giant manta rays in 2019, sightings were rare throughout the U.S. They are observed along coastlines, islands, offshore pinnacles and seamounts, or observed surface-feeding both inshore and offshore. Oceanic manta rays inhabit areas of high productivity across tropical, sub-tropical and temperate waters. Although populations appear to be fragmented, and across ocean-basin travels are likely to be rare, records of individual large-scale movements across jurisdictional borders and into the open ocean support the fact that the species are capable of large movements. Mobulid rays are capable of making significant movements across broad geographic ranges throughout pelagic and coastal waters. In addition, a low rate of exchange of individuals between populations is suggested, which makes it even more vulnerable.
Like other elasmobranchs, the Giant manta has long gestation periods and low fecundity, which makes them highly vulnerable to any kind of exploitation such as fishing.
Their frontal lobes help driving water to their mouths where planktonic organisms are filtered. The oceanic manta ray, attains a maximum disc-width of 680 cm, but averages between 400 – 500 cm. The Mobulidae family are planktivorous elasmobranchs comprised of manta and devil rays (ten extant species), with a circumglobal range all are recognised by the cephalic lobes used for feeding, a stingless tail, and wing-like pectoral fins. French : Raie manta Giant Manta Ray (Mobula birostris)©Andrea Marshall
0 kommentar(er)
