Marine Mammals as Oceanographic Sampling Platforms

  • Thomas G. Smith
Keywords: Beluga whales, Animal tagging, Animal live-capture, Biological sampling, Animal health, Arctic cod, Predation, Marine ecology, Polynyas, Energy budgets, Animal food, Animal behaviour, Marine mammals, Sea ice, Animal migration, Animal distribution, Oceanography, Instruments, Plankton, Fishes, Animal population, Ocean-atmosphere interaction, Biological productivity, Water masses, Trophic levels, Satellite communications, Remote sensing, Arctic waters


Thirty years ago, at a meeting devoted to finding new directions for Arctic biological oceanography, it was suggested that marine mammals might some day be used as "educated" oceanographic sampling platforms. They are "educated" because, through millions of years of evolution, they have developed the ability to find and consume such prey as the arctic cod, Boreogadus saida, a keystone ... Arctic species that to this day has largely eluded the efforts of scientists who have tried to study it .... The ice-covered and ice-filled waters of the polar regions have thwarted the attempts of oceanographers to study the Arctic marine ecosystem. ... Arctic seals, whales, and polar bears have been studied much more intensively than organisms lower down in the marine trophic pyramid. Studies of bears and seals have shown that large inter-annual changes in productivity occur in certain regions of the Arctic .... Studies of higher vertebrates have resulted in some interesting recent attempts to apply the "top-down" modeling approach. Such modeling uses the energy requirements of bears, seals, and whales to estimate the energy flow through the ecosystem ... or to calculate the standing crops of upper trophic-level components ... of regional Arctic marine ecosystems. To date, this appears to be the most practical and workable means available, but the assumptions and quantitative uncertainties at various stages in the model make it a blunt tool. ... The advent of satellite-linked VHF and other satellite-based remote sensing has opened the doors to research on a large geographical scale and an intensive schedule of sampling, both essential to furthering our understanding of Arctic marine ecosystems. ... One of the most interesting results from studies to date is that belugas consistently go to certain deep water areas to feed, in some cases traveling great distances from the center of their summer distribution to do so. ... The first stage in satellite-telemetry studies of some Arctic marine mammal species is being completed. The seasonal movements and annual migrations of polar bears and belugas are becoming well known for many of the North American stocks .... The next major leap forward in the study of Arctic marine mammals will be to use them to their full potential as "educated" oceanographic sampling platforms [i.e. attempting to relate their distribution or behaviour to physical oceanographic parameters]. ...
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