![]() ![]() 2014) or reproduction, in response to strong seasonal weather patterns such as the monsoon season (Anderson et al. The seasonal movements and longer distance migrations that do occur are thought to be related to seasonal shifts in resource use (Dewar 2008 Couturier et al. 2014) providing additional support to the notion that individuals remain within restricted home ranges. alfredi as well, with photo identified individuals being seen at the same aggregation areas over short and long time periods (Homma et al. Long-term site fidelity has been confirmed and quite commonly reported in dedicated photographic studies of M. 2008 Marshall 2009 van Duinkerken 2010 Kessel et al. Other telemetry-based studies have demonstrated individual variation in movement patterns but agree that home ranges are relatively restricted and that individuals regularly and repeatedly visit known sites within a larger home range (Dewar et al. alfredi moved across wide geographical areas along the eastern Australian coastline, individuals often returned to the area they were tagged. Aplethora of other studies confirm the regular, habitual use of shallow water habitats, particularly cleaning stations, where individuals are cleaned by attending fish while they socialize with conspecifics (Dewar et al. alfredi around the Palmyra Atoll in the Pacific swam offshore but no further than 126 km from the atoll, suggesting that their dependence on shallow inshore reefs for cleaning may limit their range into open ocean environments. Perle ( 2011) also noted that satellite tagged M. Notably the individual rays tracked in this study occupied both regional shelf and offshore waters swimming up to 155 km off the continental shelf presumably to forage in deeper waters. 2014) and venturing as far as 520 km in any one direction from the tagging site. alfredi in Australia, satellite tracked reef manta rays moved across a latitudinal range of 1035 km along the northern eastern coast, travelling up to 2441 km in 118 d (Jaine et al. 2014) and Mozambique (500 km in Marshall unpublished data). alfredi have occurred along continental coastlines, in locations like Australia (650 km in Couturier et al. However, the longest documented straight-line movements of M. 1999 Kitchen-Wheeler 2008 Germanov and Marshall 2014). alfredi can and often do make inter-island movements between neighboring islands up to 450 km straight-line distance apart (Homma et al. alfredi tagged in the north of Raja Ampat did not venture to the southern end of the seascape a distance of only 180 km. ( 2011) reported that despite considerable effort, no matches were found when cross referencing 290 individual manta rays from one study area in Maui, Hawaii and 145 photo-identified individuals in waters off Kona on the Big Island, a transit distance of only ~ 150 km. alfredi’s range may be quite small (Kessel et al. birostris, with a fairly restricted home range for such a capable swimmer. alfredi appears to display a more resident behavior than M. 2017) but published accounts report this species occurring only as far east as Fatu Hiva (10° 29_ S, 138° 37_ W) in the Marquesas Islands (Mourier 2012). alfredi is also commonly encountered in the West Pacific (Lawson et al. alfredi is widely distributed throughout the Indian Ocean, including large populations in isolated island chains like the Maldives and Chagos Archipelagos (Lawson et al. alfredi from the Atlantic or on either side of the American continent (Lawson et al. To date there have not been any verified or published records of M. birostris, the more widely distributed species, exhibits a broad, circumglobal distribution in all three of the world’s major oceans (Kashiwagi et al. Further investigation is required to confirm existing distribution information and to fill in the gaps in areas where little to no information is currently available. For instance, the global distributions of both recognized species, Mobula birostris and Mobula alfredi, have, to a large extent, been inferred or projected from opportunistic sighting records, a few dozen focused studies, fisheries data, historical records and perceived habitat suitability (Kashiwagi et al. Despite a surge in effort over the last two decades to study manta rays, many key aspects are still poorly understood and require additional investigation (Stewart et al. Most members of this ray group are highly threatened and may face extirpation where targeted in large fisheries (Couturier et al. Understanding the range and distribution of pelagic and highly mobile species, like Mobulid rays, is of critical importance.
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