Health Assessment of Weddell Seals, \u3ci\u3eLeptonychotes weddellii\u3c/i\u3e, in McMurdo Sound, Antarctica

The demography of Weddell seals in eastern McMurdo Sound, Antarctica, has been well studied during the past three decades (e.g. Stirling 1971; Siniff et al. 1977; Testa and Siniff 1987; Hastings and Testa 1998; Gelatt et al. 2001). Detailed life-history data are available on thousands of seals tagged as pups in McMurdo Sound, making this population a rich resource for wildlife health studies because health parameters can be evaluated in the light of reproductive histories and genetic relationships of several generations of tagged seals. Recently, evidence of exposure to diseases generally associated with domestic animals and feral wildlife has been detected in Antarctic wildlife (Austin and Webster 1993; Olsen et al. 1996; Gardner et al. 1997; Retamal et al. 2000; Foster et al. 2002) and this has generated concern and debate regarding the risks of disease introduction to Antarctic wildlife. Antibodies to viruses that have caused large die-offs in phocids in other areas of the world have been detected in Weddell seals (Bengtson et al. 1991), and there is a historical report of a mass die-off of crabeater seals that may have had a viral etiology (Laws and Taylor 1957)

Equipment and Methods for Radio Tracking Freshwater Fish

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Fishing for data in the Ross Sea

The public perceives a certification by the Marine Stewardship Council (MSC) to mean an environmentally friendly fishery, not one characterized by the \u201cdearth of key data\u201d. Significant data deficiencies lead to conclude that an eco-friendly label for the fishery of Ross Sea Antarctic toothfish (Dissostichus mawsoni) is scientifically indefensible. Credible life history data are missing: spawning areas, eggs, and larvae have never been found, spawning intervals are unknown, and most density-dependent aspects of ecological relationships are undetermined. Stock assessment is problematic because severe Antarctic pack ice conditions for more than 9 months a year prevent scientists from effectively using standard models, which require random tagging over time, space, and age classes. The number of fish harvested by illegal, unregulated, and unreported fisheries is likely substantial. Finally, ecosystem effects of removing 50% of spawning biomass of this slow-to-mature species are unlikely to be neutral. The large, adult toothfish targeted by the fishery are a key structural link in the food web of the Ross Sea, currently the most pristine marine area on Earth. Instead of a certification that lacks proper data, a moratorium should be placed on further Ross Sea fishing until the quality of science at least equals that of certified fisheries elsewhere