Island’s seals offer an autumn sight to behold
FOR many, autumn’s arrival means watching the leaves turn crisp as they fall from the trees.
For others, it could mean jays burying acorns or hedgehogs gorging on food in preparation for the winter months ahead.
For RSPB Ramsey Island staff however, autumn’s arrival is heralded by grey seals coming onto the island’s shores for pupping season.
The Pembrokeshire coast has the largest population of breeding Atlantic grey seals in the Irish Sea and southwest Britain, while RSPB Ramsey Island supports the largest proportion within this region.
Main pupping season takes place on RSPB Ramsey Island between late August and the end of October, meaning that autumn presents the perfect opportunity to witness this wonderful natural spectacle first hand.
Grey seals give birth on RSPB Ramsey’s beaches and in numerous sea-caves around the island, which can make it difficult to see exactly how many pups are born each year.
What we can do, however, is count the number of pups born on the large beach sites to give us an idea of how the population is doing. Using this counting method, an average of 320 pups can be seen on RSPB Ramsey each year.
Nevertheless, we believe that these charismatic animals only represent around 50% of the total pups born on the island, and that the actual figures could reach between 500 and 760 pups.
When born, pups will weigh an average of 14kg. Yet, when it comes to being weaned at between 16 and 18 days old, and subsequently abandoned by their mothers, the pups will have ballooned to an average weight of 45kg.
To achieve this great natural feat, the mothers must provide 2.5 litres of fat-rich milk each day to support their growing pup. And to raise their growing brood, mums will use 30,000 calories a day – the energy equivalent of a human eating 285 bananas a day.
Many of our grey seals are creatures of habit, giving birth on the same beach, on the same day, each year. Some, however, make the decision to move between sites, with some moving onto our neighbouring island over at Skomer.
To help identify the females from one year to the next, RSPB Ramsey Island wardens use a clever piece of “spy” software, where photographs are taken and individual spots and markings are analysed.
Then, if the same grey seal is spotted for a second time the software would flag a match, allowing RSPB Ramsey Island staff to discover the animals’ movements outside pupping season. The island’s seals have so far been spotted as far north as Anglesey and as far south as Cornwall.
So many seals come to pup on RSPB Ramsey Island that they can give birth in the most unlikely – and random – of places. Each year, five or six cows will give birth in the island’s busy harbour, oblivious to boats, people, sheepdogs and quad bikes – with one grey seal even giving birth in front of 40 school children last year.
Our iconic seabirds may have left for winter but the seals are certainly an autumn sight to behold.
RSPB Ramey Island is open until the end of October and for more information on our seals and their growing brood please email ramsey.island@rspb.org.uk