Algal toxin impairs sea lion memory and hippocampal connectivity, with implications for strandings

Red tides make dinner hard to find Domoic acid (DA) is a neurotoxin produced by marine algae. When present in large amounts, it is harmful to marine organisms and to humans. Cook et al. tested California sea lions being treated at a marine mammal rescue facility. Animals that had evidence of exposure to DA had lesions in their hippocampus and displayed reduced performance on spatial memory tasks. Because such tasks are essential to foraging in a marine environment, increasing exposure to DA may be contributing to increasing sea lion strandings. Science , this issue p. 1545