Quantifying the Effects of Diver Interactions on Manta Ray Behavior at Their Aggregation Sites

Manta rays ( Mobula birostris, Mobula. cf. birostris , and alfredi ), the largest mobulid rays, are subjected to exploitation overfishing in certain parts of world. Tourism has been supported as a sustainable alternative for conservation species, potential source economic spillover local populations. Nevertheless, effects tourism over these highly social animals remains unknown. aggregate at three sites Mexico: Oceanic manta M. birostris) The Revillagigedo Archipelago Banderas Bay Pacific. Caribbean ) around Isla Contoy National Park Caribbean. We analyzed behavior using video data collected by researchers operators determine how diver behaviors techniques (SCUBA free diving) affect them. Diver activities were grouped into passive active categories. described 16 them four behavioral states: Directional, erratic, attraction evasion divers. modeled sequence exhibited via first order Markov chains. Our models accounted when modeling changes behavior. displayed higher frequency erratic than Contoy, while transitioned more often. responded similarly both At freediving sites, from less frequently Bay. Changes ray similar but mantas with increased food availability could be reason reduced response toward divers this site. existence additional stressors such traffic causing site respond This study, its kind oceanic highlights that regulations use best practices vital achieving longer disturbing encounters