The Relationship Between Krill Food Requirements and Phytoplankton Production in a Sector of the Southern Indian Ocean

摘要: Acoustic measurements of Antarctic Krill, Euphausia superba, standing stock and concurrent primary productivity are used with recently published data on Krill energy requirements to assess the importance species as a herbivore in sector southern Indian Ocean surveyed during FIBEX. It is estimated that average could satisfy daily by consuming about 3.0% phytoplankton available at time survey. Assuming linear growth exponential mortality rates, it shown ments earlier growing season were probably even lower than Since rates high (0.51–2.10 doublings d−1), suggested production area was being rapidly exploited other consumers (particularly microorganisms), some contributory loss due sinking vertical mixing. Results from bird census carried out survey, an IWC Minke Whale, Balaenoptera acutorostrata, survey previous summer, estimate seasonal consumption flying birds, squid whales. Predation seals penguins crudely extrapolation circumpolar data, giving total predator 1.4 × 106 t. This reasonable agreement growth-exponential model. similar analyses should be undertaken for areas which available. Future trophodynamic studies concentrate alternative pathways, particularly those involving micro-zooplankton microorganisms.