Marine mammals as ecosystem sentinels

Selfish sentinels in cooperative mammals.

Like humans engaged in risky activities, group members of some animal societies take turns acting as sentinels. Explanations of the evolution of sentinel behavior have frequently relied on kin selection or reciprocal altruism, but recent models suggest that guarding may be an individual's optimal activity once its stomach is full if no other animal is on guard. This paper provides support for t...

Maritime mammals: terrestrial mammals as consumers in marine intertidal communities

The phenomenon of terrestrial mammals as predators in marine intertidal communities, and thus as agents of energy transfer from sea to land, is poorly understood. We review here the evidence for terrestrial mammals intentionally entering the ocean shore at low tide in order to prey on living marine invertebrates, fish, algae, and seagrasses. We introduce the term ‘maritime mammals’, defined as ...

Marine Mammals as Oceanographic Sampling Platforms

The use of mammals as sentinels for human exposure to toxic contaminants in the environment.

The use of sentinel species shows the potential to bridge the gap between animal-based and human-based environmental health research. With regard to the assessment of environmental contamination, the use of the terms "indicator," "monitor," and "sentinel" has often been confusing and ambiguous. A set of definitions is proposed as a standard to rectify this situation. The advantages of the use o...

Brucellosis in Marine Mammals

Last Updated: July 28, 2009 Importance Brucella infections have recently been recognized in seals, sea lions, walruses, dolphins, porpoises, whales and an otter. This organism appears to be widespread in marine mammals, and has probably been endemic in these populations for a long time. The clinical significance is uncertain. A few infections have been associated with placentitis/abortions, neo...