Saturday, 7 April 2018

So what about the seals?

The seabirds have returned from their wintering grounds and are getting ready to breed but what are the seals doing?

The seals got a lot of publicity last autumn as the winter storms hit during the pupping season, so I thought I should update all seal lovers on how the seals did in the end and what has been happening this season.

New born seal pup looking a little water shy

There is some good news: even though a lot of pups and weaned youngsters were affected by the storms last autumn the end result of the breeding season was not as disastrous as we had feared.

We know the fate of nearly all 225 pups with reasonable certainty, only one pup's fate was completely unknown. 170 Skomer pups are assumed to have survived, giving a survival rate of 76%, which is only 2% lower than the average since records began.

This relatively good survival rate is rather astonishing given the two storms (Ophelia (16/10) and Brian (21/10) which hit Skomer with immense force during peak pupping time. Storm Ophelia developed wind speeds of over 100km/h and the weather station at St. Ann’s Head measured wave heights of more than 16 meters. Ophelia washed roughly two-thirds of the white coated pups off the beaches. Storm Brian, only five days later, was less severe but no less devastating, sweeping some of the remaining pups away. 

Well grown seal pup but only 14 days old

The reason why the overall breeding season was still relatively positive, can be explained by the very good start and end to the seal pupping season. 

Luckily, by the time the storms hit many pups had already left the natal beaches, as they take approximately three weeks from birth to weaning.  A good end to the seal pupping season, and the fact that some of Skomer beaches are more sheltered than the ones on the mainland, also contributed to a higher survival rate than on the mainland.

Sadly the mainland breeding season wasn't such a good one with a survival rate of only 60%.

Skomer and MCZ mainland (Marloes Peninsular) seal pup survival rate 1983-2017

And what has been happening this spring? The seals haul-out mainly on North Haven beach to moult. They shed their old fur and, as they need a lot of energy to grow their new pelage, they take every opportunity to rest on land, or in our boat...

We conduct daily seal haul-out counts in North Haven and most days we observe over a hundred animals.

Seals provide endless entertainment. Here are just a few things we have observed and learned about them this spring:

Seal snot is tasty and nutritious - at least when you are a Turnstone
Not only seals eat fish - Ravens too - which seems to puzzle this seal a bit
Not every seal needs a comfy Zodiac to sleep in, some are quite content with a rock as a pillow
Trixie is still around! She was in North Haven most of last year and she is still here (Orange tag with the number 80191)
And here is Velma with an orange tag with the number 80204
(Skomer Warden)


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