The report on the latest population estimate for harp seals off the east coast of North America was released in late March without fanfare and therefore no media attention.
This was one of the missing scientific reports mentioned in my State of the Polar Bear Report 2019 released in February (Crockford 2020): results of surveys promised for months or years by early 2020 but not delivered.
Not surprisingly then, we find the report has good news: the population estimate of harp seals in the NW Atlantic has risen to about 7.6 million (range 6.55-8.82) animals (DFO 2020), up from 7.4 million in 2014 (DFO 2014).
Note that the survey was done in March 2017, a low ice year for the Gulf of St. Lawrence (see discussion below) and while this may have resulted in some increased mortality for pups born there, it is also known that many ‘Gulf’ pregnant females will instead have given birth off Newfoundland and Labrador in a whelping region called ‘The Front’.
Apparently, these factors were accounted for in the population model.
Harp seal pups born at the Front are an important food for the Davis Strait polar bears.
This increase in the prey base for the Davis Strait polar bears suggests the bear population may have grown substantially since the last survey in 2007 (Peacock et al. 2013; Rode et al. 2012).
The Davis Strait is the only subpopulation of polar bears officially considered to have ‘likely increased’ in 2018 by Environment Canada.
A new Davis Strait population size survey was apparently completed in 2018 but the results are not yet available (Crockford 2020).
Highlights, quotes, and figures from the harp seal report below.
Dr. Susan Crockford is a zoologist (former adjunct professor, University of Victoria) specializing in Holocene mammals, including polar bears and walruses. Her new book is called The Polar Bear Catastrophe That Never Happened (Amazon).
Read rest at Polar Bear Science
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