Apologies it's been so long since the
last update. We've been hectic busy here with the spring arrival of
the penguins, petrels and albatrosses as well as the summer staff –
the returning base commander, new technician, a couple of senior
scientists and our replacement field assistants. We'll be spending
the next few months here working with and handing over to them.
As I was away at this time last year I
missed one of the unique experiences of Bird Island; the fur seal
season. This started seriously around the beginning of November when
the big males started establishing territories on the beach. At 2m
long and weighing around 150kg they are by no means the largest seals
in the sub-Antarctic but they will not give ground to anyone. As they
are more like sea lions than the phocids (elephant and leopard seals
as well as the grey and common found around the UK) they are very
quick and agile on land.
Charging up river, a male Antarctic Fur Seal. |
A male arriving at a crowded beach will
have to charge up the river (where no one holds territory) fighting
off other males from either side. If cornered he will try and be
repelled by a demonstration of superior size, but it won't take much
for them to start fighting – biting and thrashing – and the
majority have scars somewhere on their upper body.
The males are holding out for the
return of the females. They face an equally difficult charge up the
beach as they will try and be herded into harems. The largest males
with the best locations will have the best chance of attracting and
keeping them, outside our window one big guy is keeping his eye on 31
ladies and their pups.
The pups are born within a few days of
their mothers returning from the ocean. Cast an eye over the colony
at the right time and it won't be long until you see a female
writhing round and giving birth to a little puppy that quickly shakes
off its birth sack, opens its eyes and starts crying for food.
There's a lot of calling as the mums and pups bond with each other as
it's not long (about a week) before the former head back to sea to
feed and when they return they need to recognise their young by call
and by smell.
Female and newly-born pup taking its first look at the world. |
A female working out which of these two attention-seeking puppies is actually hers. |
Once left alone the pups start to
interact with one another, climbing, sniffing and play fighting. If
there's no one else around they will happily play with their own
flippers.
Dreaming of milk, a content pup. |
Less than 1% of the pups are born blonde. With very few natural predators (the occasional leopard seal or orca) they tend to survive as well as the more typical black ones though they stand out more. |
A stand off between a pair of puppies enjoying the chance to play while their mums are away. |
A definite winner in this little battle, though the loser was straight back up for another bout. |
95% of the world population of
Antarctic Fur Seals Arctocephalus gazella is based around
South Georgia with population estimates of 1.5 to 4 million. This has
hugely increased in the last 50 years, by which point they were
nearly hunted to extinction. Bird Island, being largely inaccessible,
was one of their last strongholds.
Much of the science and research being
done on these species focuses on finding out where they feed, what
they're feeding on and how keeping track of how healthy the
population is. Other projects have focused on their genetics and
learning more about mother-pup interactions. I've been helping out
over on the special study beach where the pups are weighed and
samples of their umbilical cords are taken for genetic analysis.
While some pups put up much more of a struggle than one would expect of their 5kg frame, others fall asleep in your arms. |
Jerry.
Congratulations on this great blog.
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