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.
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.