Sunday 3 December 2017

3rd of December: Number crunching

Today's Grey Seal count on Blakeney Point takes the total pups born, so far this season, to 2,395 (116 births in the last three days). This is just eight less than last year's total already.

This figure is 58 less than the record season total: 2,453 three years ago in winter 2014/15:


Year Total pups born
1999-00 5
2000-01 ?
2001-02 25
2002-03 50
2003-04 80
2004-05 100
2005-06 175
2006-07 213
2007-08 297
2008-09 433
2009-10 603
2010-11 789
2011-12 973
2012-13 1248
2013-14 1614
2014-15 2453
2015-16 2372
2016-17 2403

It looks like the 2017/18 season could be set to be a record-breaker, although birth rate continues to slow: dropping to an average of 38 per day over the last three days, from 52 per day during the three days before (a 27% decrease).

The number of cows on the Point has also decreased - from 1,849, 12 days ago, to 1,601 (a 13% decrease) - as cows that pupped early in the season have weaned their pups and left the colony. The number of bulls, in contrast, has increased from 706 to 844 in the same period.


Today's pup count was as follows:


                     Bulls   Cows   Pups*

     Zone 1      248      394      804
     Zone 2      139      508      640
     Zone 3      301      408      541
     Zone 4        80      267      360
     Zone 5          1          1          1
     Zone 6          2          3        10
     Zone 7        68        15        14
     Zone 8          5          5        15

     Total         844    1601    2395

*Total births this season - not total pups present today, as pups born early in the season have left the colony: heading into the North Sea to fish for themselves.


During today's count, we also recorded the number of weaned pups, which totalled 769. Interestingly, this is very similar to the pup count four weeks ago. This figure is 800 less than the pup count three weeks ago. As pups are weaned at about three weeks, this suggests that about 750+ pups have already left Blakeney Point; leaving approximately 1,650 pups currently on site alongside the 2,445 adults counted today: that's a total of around 4,100 seals on the beach (very close to the total seals present 12 days ago, which suggests that combined adult arrival and birth rate has been almost identical to cow and pup departure rate).


Moulting pup (Ajay Tegala)

Moulted pup (Ajay Tegala)


Pup, cow and bull (H. Mitchell)


A bit of drama to finish with:
Seal fight on the beach (H. Mitchell)

- Ajay, Ranger

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