The Antarctica field team is now shifting gears in their field work. Weddell seal pupping has peaked, and the field work is now focusing more on population surveys, and assessing seal mom and pup weights. The number of pups born in the Erebus Bay study area appears to be down some from the last few years when record high numbers of pups were born during the pupping seasons.
Last season, some 658 pups were born–one of the highest pupping numbers ever for the nearly 50 year old Weddell seal population study. This season the number will be lower. Lead scientist Dr. Jay Rotella, who will soon join Dr. Bob Garrott and the rest of the field team on the ice, noted in a previous post that, "Since 2004, annual population sizes and pup-production levels have ranged from record lows (in 2004, only 169 pups were produced, which is 38% of the long-term average) to the highest level recorded since 1967 (in 2015, 658 pups were produced, which is 149% of the long-term average)."
With the shift in focus at this point in the season, the field team will be conducting more Weddell seal population surveys, and seeking out pups and moms weighed this season to reweigh them at subsequent points during the pup nursing/nurturing period.
To conduct Weddell seal population surveys, the field team will travel over the entirety of the Erebus Bay Weddell study area counting and identifying every seal. The team will do this between 5 and 8 times over the duration of the pupping and nurturing period in order to account for all the seals that may be in the water on a single survey, maximizing the number of individual seals counted through repeated census surveys.
We'll have further data from the team as the season progresses in November.
-Mary Lynn
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