No abstract

A mass mortality of bottlenose dolphins Tursiops truncatus and Florida manatees Trichechus manatus latirostris co-occurred with a severe bloom of the toxic algal species Karenia brevis along the eastern coast of Florida, USA, between October 2007 and January 2008. Brevetoxin (PbTx), a potent neurotoxin produced by this marine alga, was detected in 69 and 92% of the tested carcasses of manatees and dolphins, respectively, at concentrations similar to those reported for earlier mortality events along the west coast of Florida. Brevetoxin was also detected in fetal and neonate dolphins, providing evidence of maternal transfer of the toxin in wild populations. This study is the first to document a brevetoxin-associated marine mammal mortality event along the Atlantic coast of Florida. It also demonstrates that, despite the rarity of K. brevis blooms in this region, significant negative impacts to marine mammals inhabiting this region can occur.