They describe the two-fold challenge: "First, biologists need to determine which populations really need recovery action, and just as important, we need to know when a population no longer requires our intervention."
The authors explain that there is very little certainly of determining when a population has recovered. "Recognizing this, we have been working to solve this problem for several populations of endangered whales with the hope that it will move us into a time where rigorous data collection and analysis, and not sentimentality, drive conservation policy," they state.
For example the western North Atlantic right whales, which have been researched extensively, may be falling peril, in part, due to the "Allee" effect, or reproductive failure due to low population density, report the researchers. They explain that biologists are currently debating whether an Allee effect is preventing recovery, or if other threats -- particularly entanglement and ship strikes -- are the cause.
Unfortunately they explain that at this point human efforts at mitigating these threats have not resulted in any substantial growth in that population of whales for two decades.
"The problem is especially challenging, because even if there were perfect information, political will and unlimited resources, it might not be possible to adopt any single action that would immediately increase the population growth rate of the northern right whale," they state.
In analyzing a variety of whales which differ in their recovery status,
the authors assert, "It may be that when large whale populations becom
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Contact: Gail Brown
gbrown@instadv.ucsb.edu
805-893-7220
University of California - Santa Barbara
27-Jun-2000