Wednesday, 21 December 2011

The story of a leg and a ring.

This is an update. Back in October I found a pair of long grey legs on Rona, and a few feathers. A carcass on a raptor kill, probably a peregrine. On one of the legs was a ring with a Finland contact. The guess was that it was a curlew or possibly a whimbrel but after sending in the ring details to the British Trust for Ornithology I have now received confirmation of the ring details.
The bird was indeed a curlew and it was rung as a nestling on 28 May this year (2011) in the middle of Finland.
This is the joy of ringing. After a whole summer of turning over carcasses and looking at dead birds legs this is the reminder of why we do it. To me it is fascinating to think of the (short ) life of this individual bird and what it has seen and done. The wonders of Google maps show me that the area where is it was rung is just south east of the centre of Finland, in an area of huge lakes. After fledging it has made a journey of 1877km if it flew in a straight line though  of course the distance would have been much further. What was its route ? I don't know, either west through Scandinavia and then to Scotland or down to the Baltic states and the south edge of the Baltic may be. Either way it is a big undertaking even for a bird the size of a curlew, especially as it was directed by instinct having never made the journey before. And on once it reach the island it just passed on its energy to a bird of prey like a baton by a relay runner. Such is the natural world.

Friday, 9 December 2011

End of Season Clear Out

With high winds forecast we had a mad rush around to close down the island for the winter.
There were few birds about, but on Tuesday morning good numbers of pink-footed geese were coming in off the sea, maybe they new the weather was due to change and wanted to get south when they could.
2 long-eared owls were still about, roosting in the top heligoland trap. The migrant birds that they usually feed on have mostly moved on so my guess is that they will follow soon or go hungry.

And across the island were weaners everywhere. These are newly weaned grey seal pups who have bulked up on a high fat diet from mum but haven't yet got the motivation to move on with the next stage of their lives. You have to be careful as you go around the island as they can literally be everywhere. Lurking in muddy pools.
I don't know how they got there and how they will get out but some were sunbathing on cliff top ledges.
While others turned up in and around the buildings.

This weaner liked a sea view having made it way up nearly to the South Horn.
While this one was sleeping on the path back to the cottages, I literally stepped over it.
And so with the buildings locked up, the laundry, scientific samples, tools and equipment bagged up we headed off for a wet and bumpy ride back to Anstruther. This really is the end of the field season for the May. The island has a short period of peace over Christmas and the New Year but it all kicks off in late when January another visit is required to look at wintering shags and a chance to see another face of this special island. On the way back I made a mental note to myself - in January thermal underwear essential.

Thursday, 8 December 2011

Seal Action

Monday morning and a rushed trip out to the island to help with the closing down. Storms are forecast for later on in the week and the seal researchers have finished their work for the year so it is time to help them get their stuff off, drain down the water system and close down the buildings for the winter....and quickly. But in between cleaning out cupboards, bagging laundry and other such joyful tasks I had a chance to wander around the island. Many of the seals have left the island already, it seems like either a very early season or not so many pups as usual have been born this year but there were still plenty dotted around all corners. Most of these are weaners, that is this years pups whose mothers have feed them and then left them. They lie around for a while wondering when their next feed is coming before eventually heading out to sea. If you go quietly you can get quite close to them and it gave me a chance to have a closer look at these amazing animals.

They have fantastic whiskers. They are incredibly sensitive and they use them for finding food underwater where there isn't much light.
Some of the weaners spend lots of time messing around in muddy pools and end up looking like a monster from the deep. This one is coated with mud which shows off its eyebrow whiskers beautifully.
Grey seals do actually have a tail but it is just a short little stubby one that apart from helping with steering doesn't now have much use.
When the grey seal pups are first born that have a white coat. This is thought to be an adaption for when ancestors of grey seals lived on polar ice sheets and shows their geographical origins. This weaner is gradually losing its white coat and getting a mottled adult one. When they are being feed these pups don't move much and afterwards they just sleep so there is often a huge patch of white fluff left on the ground where they have moulted.
The weaners are feed for just 18 days by their mothers and grow at a rate of up to 2 kg a day on a high fat diet. By the time they are weaned if feed properly they are very fat and don't do much.
Eventually they will grow into an adult bull or cow and return to the island after 7 years at sea to start breeding. They are less cuddly and more world weary by then.

But there are always some pups that don't make it, one of the seal researchers, Jo is trying to find out why this is. Even dead they go to provide food for a whole range of creatures that eat carrion and break down carcasses such as gulls, crows, burying beetles and blowflies.