Friday, September 15, 2017

Whales: one stroke backward, one forwards

The North Atlantic right whale is as magnificent as an animal can get. Eubalaena glacialis can weigh over 70 metric tons and stretch 15 meters from its nose to its its deeply notched tail.  It bears distinctive callosities covered with white "whale lice"  on a stocky, black body.   As with all large whales, evolution hasn't really equipped the animal to be wary of still larger objects, like ships. The population, decimated first by whaling (centuries of it, going back to the first great oceanic whalers, the Basques, and  Native Americans, both in small open boats, before modern whalers had their turn), and now by fishing gear entanglement and hip collisions, dipped below 400 at one point before struggling to perhaps 450 (although a European population is functionally extinct). 

Head of right whale, showing distinctive curved jaws and callosities (Georgia Dept. of Natural Resources)

There was sad news today when a dead whale was spotted in the Gulf of St. Lawrence. This is the 11th carcass found in the Gulf this year. Others have been found off the American coast (they calve off Georgia and Florida). Necropsies of a few (such an effort is not easy to arrange, and many whales are not necropsied) and observations show a split between ship strikes and fishing gear entanglement as the causes. 
The good news is that humans are not letting the species drift into extinction.  On top of existing protections, Canada imposed strict speed limits on ships in the Gulf over 20m long.   Meanwhile, in the eastern Pacific, where blue whales and others have been subject to the same lethal pressures, crabbers are part of a new program to track traps that may be scattered by storms and currents to become "ghost gear," drifting without supervision. Rather than engage in the complex politics of banning crabbers from large areas (a step the nonprofit Center for Biological Diversity, which is filing suit over the issue, says is still needed) skippers fix the position of drifting pots via GPS.  The next step, supported by fishery officials and the nonprofit Nature Conservancy, is to pay crabbers $65 for every pot they are able to take on board and return to port, where the original owners are usually happy to cough up $100 to get the $250 pots back.  
The whales are in deep trouble on both coasts, but humans aren't just letting it happen the way we used to.   
THANKS TO environmental scientist Laurie Baker, who keeps me up on much of the whale news. 

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