Friday, December 9, 2011

Kleenex's Daughters

Both Echo (#2642) and #3142, 1996 and 2001 calves of Kleenex #1142 were seen in the Bay of Fundy by the New England Aquarium this August and/or September.  Both were mothers in 2010 and both brought their calves to the Bay as they were also brought by their mother Kleenex when they were calves.

Right whale mothers take at least a year to recover the weight they lost nursing their calves for a year, plus a year pregnancy which gives a minimum three year calving interval.  The New England Aquarium are concerned about both of Kleenex's daughters because they have not adequately recovered their weight and are showing signs of stress: leaner bodies and with Echo, rake marks below her blow holes.  These are parallel white marks that are only present in under weight, sick or stressed animals.

Photograph taken by the New England Aquarium in the Bay of Fundy in 2011 showing a thin right whale
 "Echo" #2642 with white rake marks below her blowholes.
It may be that zooplankton patches have been harder to find or fewer patches were found last year when they were nursing their calves, and both females lost more weight than usual during nursing.  Hopefully, this will improve and the health of these sisters will improve. 

A similar problem occurred in the 1990s when many of the right whales were under weight.  Odd white skin patches developed on many individuals and calving intervals increased to over six years between calves.  Lack of adequate food (zooplankton) was suggested.  There was much concern for the right whale population because, combined with high accidental mortalities, the population began to decline.  That trend was reversed for the last ten years when the population began increasing when the number of calves born rose dramatically (an average of 22 calves as compared to just over 11 calves prior to 2001).  Are we heading for lower numbers of calves again because females are thinner?  Or is this a blip that will disappear quickly as food resources recover, if that is the problem? We shall have to wait and see.

Radiator Update

Last photographed July 18, 2009 on George's Bank at the mouth of the Gulf of Maine, Radiator was trailing rope with a yellow buoy.  The attachment point for this was unclear.  He hasn't been photographed since but that is not unusual with some right whales who sometimes avoid areas where researchers or others are more likely to be.  Right whales are constantly on the move even when they are in feeding areas.  The shifting zooplankton patches and their never ending cruising around the North Atlantic makes it difficult to always know where they are or may turn up.  While in general whales move northward during the summer to feeding grounds and southward to wintering areas - this can be as far as Florida for pregnant females and young whales, or further north for males and non-pregnant females, these areas are fluid and can change yearly.

Right Whale lifting tail flukes in a dive off Grand Manan Island, Bay of Fundy
The New England Aquarium maintain the North Atlantic Right Whale Catalog (http://rwcatalog.neaq.org/) which is a great source of information about where individuals have been photographed, as well as photographs of each whale.  The Center for Coastal Studies in Provincetown, MA, keep files on right whale entanglements.