Wednesday, 31 July 2013

Hungry gulls

 2 chicks that have survivied
One of the things we don't study at the moment is how successfully the gulls are at breeding. We count the total number of nests every 2 years but we don't count how many chicks per pair are produced and this year that would have been interesting to know. It is only an impression but this year it seems that the gulls, the lesser black-backed and herring, have been struggling for food. Walking through the colonies and there aren't many live chicks but lots of dead ones. We have also seen fierce predation of the terns and other seabirds, maybe fiercer than other years. It maybe that with other normal food sources such as land fill sites, food waste and by-catch from fishing boats being reduced the gulls are having to look elsewhere. They are supremely adaptable and are able to take advantage of a whole range of food sources. One such food source are their gull neighbours with gulls being quite able to eat their neighbours chicks and eggs. I had a look around the nest of one of the pairs of greater black-backed gulls at the South Ness and it is surrounded with the remains of gull chicks so it is clear where many of the chicks of that area have gone. It is just something that will have to be watched and though herring and lesser black-backed gulls are no so popular with the public as other seabirds they have the same conservation status and protection so can't be ignored.
This is another example of the careful balance that exists and that if it is changed in one way it can be difficult to predict how nature will restore the balance.

 And lots that haven't

Tuesday, 30 July 2013

A pile of poo

 One of the results of having so little rain on the island is that the sheer quantity of bird poo that falls on the island during the season is much more obvious because the rain hasn't washed it away. Until a few days ago when we had some big showers, the island was covered in white with the seabird cliff colonies gleaming bright white in the sun. Of course this shouldn't be a surprise as with 200,000 large birds all on a high protein diet living in a small space there is going to be a lot of poo. What these birds are doing are hoovering fish up from a very wide area, several hundred square miles around the island, growing chicks on the fish and squirting out the waste. This results in the energy production of the sea being concentrated onto the island and running off into the sea around. This does have an effect on the environment with a massive rearrangement of energy and chemicals,  for instance the UK seabirds emit 2700 tons of ammonia per year and are the largest point source of ammonia in the country. This doesn't really compared with the amount that farm animals produce across the UK but in remote areas where farming is less intensive seabirds are often the most significant source of ammonia.
On the island you can see these for once it does start to rain a slurry of liquid bird poo runs off the cliffs and forms clouds in the sea around.
We get used to it and don't notice the smell but it does affect life on the island. In peak puffin feeding time eating dinner outside can mean a liquid addition to your meal from above. And the rain water collected from the roof becomes what is really dilute bird poo and so isn't suitable for anything other than flushing loos. So a dramatic reduction in seabirds can have a knock on effect on other creatures and ecosystems that are adapted to live on this redistributed energy. You can never look at any one group of wildlife in isolation.
And less poo would remove one of our favourite occupations - spotting pictures and faces in the patterns from above!

Sunday, 28 July 2013

Night time islanders - stormies and pufflings

 Last night we got a glimpse of what happens n the island under the cover of darkness.
It was a stormy netting night. This means we were after storm petrels, probably the most mysterious seabird found in the UK. These are tiny seabirds, only about the size of a house martin and they spend the day far out at sea out of sight of land and their biggest danger, gulls. Under the cover of darkness they come closer to land and that is when we can catch them. By playing a tape of their calls we can attract them into mist nets to ring and release them.
So midnight found us lying on a tarp under a mist net listening to the island sounds of the night while desperately trying to keep eyes open and brain awake. Suddenly a silent shadow appeared in the net and our first stormy was caught. Once up in the ringing hut and in the light of a head torch we could see the dark chocolate black colour, a clear white rump, an eye like a black bead, a shiny black beak and the smallest webbed feet you can imagine.
Six birds were caught over a 3 hour period, 5 were ringed but the sixth was most interesting. This bird already had a ring and this small marker showed the benefit of all this night netting. By looking back in the records we found that this bird was known to us. It had first been ringed in August 2010 on the island. It was then caught again on the island in August 2011, 4 times in 5 days and one of those times by myself!. In 2012 it was back and caught 4 times in 6 days and here it was again in 2013. There are no records of storm petrels breeding on the Forth islands that have been confirmed but in 1904 a bird was found in a cleft on the Bass Rock and a pair flushed from a crack on the Isle of May in 1922. So more investigation is needed to see if this bird is part of a vanguard of birds starting to breed on the island but regardless it was great to meet up again with this tiny bird  2 years later that in the meantime has clocked up thousands of miles across the  oceans including twice to the coast of Namibia in the winter.
Tossing pufflings
But stormys weren't the only island inhabitant out and about. Pufflings on mass were making their way from their burrows to the sea. They leave their burrows at night to avoid the gulls but those that head towards Kirkhaven has a gauntlet of hungry gulls to brave so those we caught up and took to the west cliffs to toss so giving them a better head start to get away from the predators. The puffins started breeding very late this year but when they did start they must have all laid at the same time as there seemed to be puffins everywhere. By the time we went to bed we must have tossed 20 missed a few and boxed up another 6 for releasing the next day. It is nice to know that we have given them as good a head start as possible for what is a hazardous life. And it they make it, they will be back in 4 years time to start thinking about breeding.

Saturday, 27 July 2013

A brief visit - latest bridled tern news.

No sign today of the bridled tern on the May today despite an early start to check for it. It was last seen yesterday evening shortly before 10pm so we think it maybe roosted on the island.  An absolutely glorious day today brought full visitor boats over with some people hoping to catch a glimpse of this big beautiful tern but to no avail. At the moment we haven't heard where it might have headed off to but we will keep scanning the tern roost for the next few days as it does seem to come and go a bit.  

Cool things on the island at the moment

We are very lucky to live out here and get to see so many cool things. Here is a selection from the last couple of days. The gannets are feeding in closer to the island, this one is just taking off after a fishing dive. With the all of the heavy showers passing through we have had some spectacular rainbows.

 The spring tides leave things normally hidden uncovered at low tide. These bits of machinery lie in one of the gullys, dumped there many years back by lighthousekeepers. I would love to know what they are from and what their story is. Now they are all rounded by the pounding of the seas.

The Mayweeds have taken over from the sea campion and are carpeting parts of the island.  Below it has to be said that the hsags and their chicks are not looking at their best at the moment. Shag chicks are ones that grow into their looks.

A green sandpiper dropped in at the loch, the vanguard of the wader movement heading south.

A large moon, clear night and flat sea make a fine sight seen on the way back to my cottage for sleep.

Friday, 26 July 2013

Bridled Tern on the May today - borrowed from the Farnes?

A beautiful evening this evening and we decided to have a BBQ to cook some mackerel we had been given by the may Princess crew. i was just about to sink my teeth into a fish when Mark started yelling. once he was coherent it became clear that he had spotted a bridled tern swooping in over the pillow, the small island next to Kirkhaven. A bit of panic followed with people running for scopes and cameras and for the next hour plus we had fantastic views of what is a stunning bird. Over the evening it kept coming and going and was last seen again over Kirkhaven at 2045.
It seems most likely that it is the bird that has been gracing the Farnes and other sites south along the east coast and this seems to be its first jaunt north. It is a first for the Isle of May and possibly only the 6th record for Scotland (to be confirmed) so all in all an interesting bird.
More information tomorrow.

Those on the twitch !

Tern chicks - we have some flying.

A young chicks using a blown over traffic cones as bit of shelter from the gulls.
 Even more exciting than puffins for some of those working on the island is the fledging of the tern chicks. The terns have perhaps one of the biggest struggles to breed successfully on the Isle of May as they choose to breed in amongst 11 000 hungry gulls, and with so many failed years in the past it is fantastic to see young terns flying around. The SNH team have put in days and days of work on the terns since they came back to the island in early May and flying chicks is what the success of the year is measured in. The way of monitoring the terns breeding success is to do a daily count of fledged chicks that gather in roosts close to or on the edge of the breeding colonies. The highest count is taken as the marker for the season. This year we are creeping up into the 40's which compared to the fact that we had over 400 nests is very poor but against complete failure of previous years is not too bad, at least there are new birds going into the population. Last year we had a highest count of 37 so we have certainly improved on that figure. we will continue to count and let you know the final figure.
 A chick that can fly.
 The wooden shelters are put down to be used by the chicks to hide from the predatory gulls.
A proud but worn out parent ! But there isn't much rest, in the next week or two the isle of may terns will start the long journey south to Antarctica to spend the winter feeding along the edge of the ice cap. Just the thought of that makes me tired.

Thursday, 25 July 2013

If it's puffins you want just come.

 The weather has turned just a little wetter the last few days and the numbers of visitors have dropped off and yet for those that come regardless of the weather, then there are fine rewards on the Isle of May to be had.
Today was a fine example, it rained for most of the morning, combined with heavy fog and this made a fairly uninspiring sort of day. Visitors obviously thought so as only 39 made it across on the 2 boats but those few passengers found a different world. As the boats approached the island the fog burnt away, the rain cleared and the island glowed in the sun. And on the island was pretty much the whole of the100 000 Isle of May puffin population. Towards the end of the season you can get some of the most impressive puffin days of the year. There are many parents still whizzing in bringing fish to pufflings down burrows but many non-breeding birds also come back onto the island for a bit of socialising. The poor weather had kept the birds on the island and every part seemed covered with puffins and the sky darkened with waves of puffins sweeping overhead. On any upstanding rocks puffins gathered with plenty of communicating going on and many had muddy bellies where they might have been doing a little bit of burrow work.

These big puffin days at the end of the season are so of the most exhilarating of the year.

 Puffins gathering outside burrows on a slope at Colm's Hole.

Once you get your eye in you can start to see the differences in ages of puffins by their different bill shapes. The first bird below is a reasonably mature birds with a large bill that is well rounded on the top. The bird below is younger than breeding age as it has a much thinner, narrower bill with a straighter top edge.

Many young birds gather on the island at the beginning and the end of the breeding season to start to get to know the local puffin community, look for a partner and a burrow and get the hang of life in a puffin colony.