Foraging Ecology and Behavior

Abstract

AbstractPhocid seals exhibit a range of body sizes and life-history traits. They forage at a wide range of spatial scales from long-distance oceanic movements (e.g., northern elephant seals) to short local trips of resident coastal species (e.g., harbor seals). Our current understanding of the foraging behavior of phocids comes mainly from northern and southern elephant seals, gray seals, harbor seals, ringed seals, and Hawaiian monk seals. Foraging tactics appear to develop rapidly within the first year of life, but the effect of age on the foraging of older animals appears to be weak. Sex differences in seasonal foraging distribution and diving behavior are evident in several dimorphic species but less evident or absent otherwise. Body size, condition, and reproductive status also influence foraging trip characteristics and dive effort. Recent studies reveal the consequences of foraging on mass gain and reproductive success and how those consequences vary with interannual and longer-term environmental change. More accurate location tags, improved dataloggers, and new analysis tools are being used to measure and infer in-situ patterns of foraging behavior and foraging success. Animal-borne instruments can also collect data on the ocean environment, which have proven useful in describing foraging behavior.KeywordsPhocidsIntrinsic and environmental driversMovementDivingForaging successLife-history consequencesNew toolsAnalysis methods