![]() ![]() ![]() alfredi aggregation in the Red Sea and is considered a globally important site for the species’ conservation. One possible exception is the Dungonab Bay and Mukkawar Island National Park (DMNP), located on the Northeastern Sudanese coast. alfredi cohorts along the eastern coast of Africa (Somalia, Tanzania, Kenya, Madagascar) are understudied but are also thought to be threatened by human activities. ![]() alfredi sightings declined by 88% over an eight-year period which is thought to have been caused by increased fishing pressure. alfredi is officially classified as “Vulnerable” by the International Union for the Conservation of Nature (IUCN) due to declines in abundance reported from several known aggregation sites. alfredi populations are at risk of rapid depletion and local extirpation in regions of sustained targeted fishing. one pup per litter ) with a very low maximum intrinsic population growth rate, M. As a highly k-selected elasmobranch (i.e. alfredi are regularly exposed to human activities and have been heavily fished in several regions, both directly for their gill plates and indirectly as bycatch. Due to their preference for near-shore habitats, M. Mobula alfredi abundance and habitat selection within these areas is often seasonal, most likely in response to predictable fluctuations in food availability and distribution. While capable of long-distance movements spanning hundreds of kilometers , the species is commonly found in shallow coastal and lagoonal habitats. The reef manta ray ( Mobula alfredi) is a large, reef-associated, filter-feeding batoid that is widely distributed in tropical and subtropical regions of the Indo-Pacific. Understanding species’ habitat selection will likely by critical to the conservation of these species in the face on anthropogenic change. As anthropogenic impacts continue to increase in coastal and open ocean ecosystems, describing patterns of megafauna movements and identifying the ecological, physiological, and oceanographic drivers of those movements is a priority. Movements can be shaped by foraging opportunities and reproductive ecology, predator avoidance, and environmental needs, all of which are influenced by scale-dependent environmental factors. The movement behavior of large marine vertebrates is strongly impacted by habitat complexity rather than evolutionary origin across a wide range of taxa. This information can be used to assist in managing and supporting sustainable ecotourism within the DMNP, part of a recently designated UNESCO World Heritage Site. ![]() alfredi are highly resident and site-attached to coastal bays and lagoons but display seasonal shifts in habitat use that are likely driven by resource availability. The current study adds to growing evidence that M. However, all these individuals were subsequently detected in the Bay, suggesting a strong degree of site fidelity at this location. Despite the high residency suggested by acoustic telemetry, satellite tag data and offshore acoustic detections in Sanganeb Atoll and Suedi Pass recorded individuals moving up to 125 km from the Bay. Modeled biological factors, including sex and wingspan, had no influence on animal presence. alfredi presence was highly correlated with increasing chlorophyll-a levels and weakly correlated with the full moon. Detections were recorded throughout the year, though some individuals were absent from the receiver array for weeks or months at a time, and generalized additive mixed models showed a clear seasonal pattern in presence with the highest probabilities of detection occurring in boreal fall. Tagged individuals were detected within the array on 96% of monitored days and recorded an average residence index of 0.39 across all receivers. alfredi were also equipped with satellite linked archival tags and one individual was fitted with a satellite transmitting tag. Together, these data are used to describe approximately two years of residency and seasonal shifts in habitat use. alfredi aggregation in the Red Sea.Ī total of 19 individuals were tagged using surgically implanted acoustic tags and tracked within DMNP on an array of 15 strategically placed acoustic receivers in addition to two offshore receivers. Dungonab Bay and Mukkawar Island National Park (DMNP), a component of a UNESCO World Heritage Site in Sudan, hosts the largest known M. Identifying critical habitats for this species is essential for future research and conservation efforts. Reef manta ray ( Mobula alfredi) populations along the Northeastern African coastline are poorly studied. ![]()
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