Spatially Estimating Disturbance of Harbor Seals (Phoca vitulina).

Tidewater glacial fjords in Alaska provide habitat for some of the largest aggregations of harbor seals (Phoca vitulina), with calved ice serving as platforms for birthing and nursing pups, molting, and resting. These fjords have also been popular destinations for tour ships for more than a century, with dramatic increases in vessel traffic since the 1980s. Seals on ice are known to flush into the water when approached by tour ships, but estimating the exposure to disturbance across populations is difficult.

Seasonal shifts in the provisioning behavior of chinstrap penguins, Pygoscelis antarctica.

Whether parents are able to adapt food gathering to rising offspring demands, or if they are controlled largely by extrinsic factors, is important for understanding key limits on fitness. Over seven breeding seasons, we studied the provisioning behavior of chinstrap penguins, Pygoscelis antarctica, at Seal Island, Antarctica, during parents' transition to leave broods of one or two chicks unguarded. By measuring the frequency, duration, and diel timing of foraging trips and the quantity of prey brought to chicks, we examined the extent to which variation in parents' feeding behavior could be attributed to provisioning costs which increase with chick growth.