Seal pupping on Skomer is drawing to a close for 2018. It has been a good season for the seals with no disasterous storm events such as Ophelia which hit last October and well over 200 pups born. At least one of the storms this year corresponded with neap tides which meant the pups had somewhere to retreat to away from the crashing waves. So it seems that survival to weaning (around 3 weeks of age) will be good this year. Of course, knowing this is only possible due to the long-term monitoring that we do on Skomer. This monitoring is of vital importance if we are to understand the population dynamics of the seals and safeguard them for future generations to coexist with and enjoy.
A Grey Seal pup, less than 5 seconds old!
Each year in July or August the first pregnant cows will return to pup on one of Skomer's beaches or in one of its secluded caves. From that point onwards the seal field workers (Bee Bueche and Ed Stubbings for the last 6 years and Dave Boyle before that) will check the beaches daily and the caves around once a week. This means that we know the date of birth of each new pup to within about 24 hours, sometimes actually catching the birth itself. Grey Seal pups are born with a white coat which is shed after around three weeks and by following each pup through to the completion of moult we are able to give an overall survival rate to this stage. We can also say how many pups were born each season and, by counting the adults (including all the major haul outs), how many seals are present. These are the equivelant of the productivity and population studies that we do with the seabirds during the summer. The final piece of the puzzle is adult survival and return rates which we do by taking thousands of pictures of the seals, mostly pupping cows, and comparing them with a huge catalogue of known animals.
A Grey Seal pup after many bouts of suckling on mums fat rich milk
Pup 158 (popular on social media this year!!!) having a suckle
Pups 158 (above) and 130 nearly moulted and moulted
Many people help us with this work, from Assistant Wardens and Visitor Officers to Long-Term Volunteers, visiting researchers and even our line manager Lizzie Wilberforce. We owe a huge debt to these people as it would not be possible to make the number of visits and enter caves as regularly without their help.
Field work involves visiting pupping beaches to check and spray pups, collect poo samples for diet analysis and skin samples for DNA analysis
A just sprayed pup
Sometimes they try and hide to avoid being sprayed...
...but obviously it doesn't always work.
One of our Long-Term Volunteers this year, Harriet Sleight, took this footage of us spraying seal pups. It shows quite nicely the process we need to go through each time we make a site visit - check spray list, spray (not as easy as it sounds), photograph, map, do this for each pup then check for poos and any dead pups to take skin samples from - quite a lot to remember.
Harriet (LTV) and Sarah K (Assistant Warden) in Matthews Wick
Harriet coming out of Matthews Wick after a successful visit
Then of course there are the bulls, which, in a rough and tumble kind of way, ensure next years crop of seal pups.
Fighting bulls attract a female's attention
Mating usually involves lots of biting and scratching!!!
Females are slowly subdued but are definitely not always willing
Once the breeding season is completely over we will write the Grey Seal Report for Natural Resources Wales who fund the work that we do on Skomer each year. The final report will be available on the trust website in the new year. See here for previous year's reports.
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