Archive for June 2018

June 19th Why so many rings on a redshank?   Leave a comment

I am in Africa and disconnected from Crail for now. But I was brought back home by a post about a Crail redshank – someone wanted to know what was the point of all those rings that I use?

I remember thinking exactly the same thing when the BTO and the Wader Colour Marking scheme gave me my combinations to start my PhD study on redshanks in 1989. Six rings? Two of them giant blue ones? And a metal one? What was the point?

25 years later I know why and I realise the wisdom of the idea. For a start we put colour-rings on because we wish to identify individuals. This way you don’t need to recapture them to know who is where and we can string together sightings from Iceland to Scotland to Africa as redshanks migrate. Birders and photographers can record colour-ring combinations, report them into the colour-ringing scheme and get to hear the individual adventure of the bird they have seen. And those of us studying the birds get important data points on the places used and things like speed of migration, age of breeding and survival. The bird in the photo is YNGN – Yellow Black Green Black. I ringed this bird on the 21st March 2011 as a bird in its first winter (i.e. born the summer before) on Crail harbor beach (east Fife, Scotland) using a net strung across the harbour entrance. The redshanks of Crail make use of the floodlit, water free harbor on cold low tide nights, and if you are lucky all fly out of the harbor using the quickest route. Most nights they don’t of course but that’s another long and cold story. YNGN is a harbour regular feeding there day and night and often gets photographed because people can get close to it, looking down from the harbor walls as it feeds on the mud below. I caught it again in 2012 and 2014, which was the last year I was regularly catching at Crail. So with the colour rings I know that it is 8 years old (27 years is the longevity record) and that it always feeds in a small area of Crail around the harbor. Although it hasn’t happened yet with this bird, other Crail birds have been seen all along the eastern Scottish coast to Aberdeen, the May Island and two in Iceland where most probably breed. So I can connect our Scottish east coast population together with the Icelandic population, and I am getting an idea of their survival rate. All very useful when thinking about conserving our declining populations of redshanks.

OK I hear you saying, but why so many rings – surely one or two would do the job? And what about those big blue ones. Well, believe it or not, there are tens of people that study redshanks around Europe and they all need to have a scheme identifier. This allows a scientist like me to use my own colour-combinations without fear of duplicating someone else’s and messing up their study. And my redshank move all over Europe as do theirs. I put two tall blue rings below the knee on all my birds so that when someone reports a sighting, the scheme identifier knows it is my bird and they can put me in contact with the person who sighted it – as in this case – to tell the story. And of course I get that important data point. The four rings above the knees, two on each leg, are in different combinations for each individual. I don’t give names to my birds but YNGN is as individual to me as my dog – I see it nearly every day during the winter as I walk around the shore of my village (with my dog). This was never the purpose of colour-ringing the redshanks, but it is a pleasant consequence. YNGN is one of my long term neighbours and gives me as much a sense of home as all the familiar people I share Crail with.

I colour-ring the redshanks because I want to measure their survival rates and determine how often they are killed and eaten by birds of prey. I have published 27 papers on redshanks to date giving us vital information of how they live and die in our increasingly man-affected and shrinking habitats. Redshanks are pretty resilient but still we need to know where to conserve areas and when to minimise disturbance to them to give them a fighting chance of survival into the future. One of the papers I am most proud of was a study where I looked at the effects of all those rings on redshank behavior and their survival. After all, if I have to use all of those rings I should at least know their detrimental effects if there are any. I compared the feeding rates and the location and time spent feeding for birds with no rings and those with lots of rings: I couldn’t find any differences at all. If rings upset redshanks then we would expect them to have to compensate by feeding more or taking risks and feeding in dangerous areas. But most significantly I compared the number of colour-ringed redshanks that were killed by sparrowhawks and peregrines through the winter with those taken but not ringed. I was lucky enough to be working on an estuary close to Crail where many redshanks were killed each winter – it was a little like the Serengeti in miniature with redshanks the wildebeest, sparrowhawks the leopards and peregrines the lions. Because so many were being eaten (the population wasn’t affected by the way – in years with few redshanks the predators ate other things – again like the Serengeti) I was able to really see whether colour-rings affected the probability of being targeted and killed. I would have been able to detect even a 1% difference in survival rate over the winter. You might expect all that redshank bling might attract a raptor or reduce a redshank’s ability to escape. But I found no effect at all (the difference was statistically insignificant and actually opposite to what I expected).

So, I have moved on from my initial reaction of horror at so many rings on my redshanks to an appreciation of them. I can easily identify individuals – and so can everybody else. The redshanks are not harmed by them and we gain useful information for a long time. I hope to see YNGN for another 20 years around Crail. It will still be in Crail harbor then if it is still alive, still being photographed and still being reported to me via the colour-ringing scheme to add to my survival study. And who knows – those conspicuous rings may lead to an Icelander spotting it in their field so I will find out its summer home as well as its winter one.

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Posted June 19, 2018 by aboutcrail in Sightings

June 7th   Leave a comment

There were a pair of sand martins prospecting the pipes set into the concrete banking at Roome Bay today. Sand martins are hole nesters, usually digging their own tunnels into sandy river banks, but they will use pipes and existing holes. The last time they did this in Roome Bay was in 2011. We had a small colony for about 5 years. Never more than about 4 or 5 pairs. They nest in small numbers all along the coast and they do seem to shift colonies after every few years – or colonies fail and new ones arise. It is nice to have them back. Sand martins have a nice scratchy warble of a song and a very flickery flight: they are obviously brown above so easy to identify once you have worked out that they are a swallow.

A sand martin at one of the pipes in Roome Bay they have used for nesting

Posted June 8, 2018 by aboutcrail in Sightings

June 4th   Leave a comment

I visited the May Island today. A 09:00 sailing out from Anstruther on the May Princess. The haar made the crossing a little cold but the visibility was more than good enough with the gannets making spectacularly close fly-bys as usual. When we got to the island it started to lift and we were greeted by the largest number of puffins I have ever seen on the island. Something about the weather, or the time of year, just at the point of hatching and before serious chick feeding, meant that just about every puffin was on the island and not down a burrow. Or so it seemed – tens of thousands – if not the full 94,000 that are probably in residence this year (based on last year’s count). It is hard to describe that many puffins loafing in great flocks on the turf, or clustered in lines on the old buildings, or flying up like a cloud of insects when a great black-backed gull flew too close. You need to see it yourself. If you haven’t been to the May Island in puffin season, then go. It really is one of the best wildlife experiences you can have anywhere. And never mind the thousands of guillemots, razorbills and kittiwakes along the cliffs; the eider ducks nesting everywhere, but so cryptic and unmoving that you don’t notice them until you stop somewhere to find one literally by your feet at the side of the path; the blizzard of arctic terns and the grey seals loafing on the rocks. And everything at very, very close range. It’s one wildlife experience when you hardly use your binoculars.

Eider on a nest on the May Island

The seabirds were the real stars of today – their sheer number and closeness. But there were some other things on the island. A couple of spotted flycatchers, a willow warbler, a chiff-chaff and a very elusive rose-coloured starling (a pink and black version of a starling from central Asia). I probably had a brief glimpse of it – a pale coloured starling amongst a flock of puffins suddenly flying off from the beacon at the top of the island. But not “tickable” and I am consoled by the fact that I saw the last rose-coloured starling on the island in 1992. I will wait until we get one on the mainland for the Crail list: they are more usual in the autumn, although have become much rarer vagrants to the UK in the last 20 years. I also had my first common tern of the year – a challenge to pick out among the hundreds of arctic terns.

Some of the tens of thousands of puffins to be seen daily on the May at the moment

Posted June 6, 2018 by aboutcrail in Sightings

June 3rd   Leave a comment

The was a lesser whitethroat singing at Barnsmuir this afternoon. This is a fairly scarce migrant around Crail and I am lucky to find one or two every spring and autumn. They do breed in the East Neuk – one of the few places in Scotland where it happens regularly. The last possible breeder I had was a few years ago in the dense garden between the shore boating pond and the doocote in Roome Bay. You hardly ever see them but their song is a very distinctive rattle. The bird today was in a dense, high hedgerow with mature trees all along it – very suitable for breeding. It will be worth checking out in a couple of weeks to see if it is still singing. But this bird may just as likely be a migrant. We are at the end of the migrant season although lesser whitethroats are late arrivers to Europe, migrating around the eastern side of the Mediterranean and then across Europe to get to us, rather than taking a more direct south – north route as with the common whitethroat. On the way home to Crail I passed one of the yellow wagtails diligently bringing food to the nest, and seemed to be putting up meadow pipits from their nests in the grass alongside the dirt track besides the Anstruther road all the way back to Crail.

There are meadow pipits everywhere – they are not scarce breeders like yellow wagtails or lesser whitethroats

Posted June 3, 2018 by aboutcrail in Sightings

June 2nd   Leave a comment

It seems a much quieter weekend than last. The winds are still fairly good but there was no sign of anything new in at Kilminning. In fact, the shore at Fife Ness and Balcomie felt more summery than spring. There was a flock of about 40 arctic terns loafing on the rocks at low tide like it was August. They should be busy breeding so maybe these were off duty birds. A pair were mating so perhaps they are just at the stage before laying when the females need to feed up so they can produce eggs and the males stay very close to their females to ensure that they are the ones fathering her chicks. I will be able to see what stage they actually are at when I visit the May Island on Monday. The first moulting goosander of the season swimming around the rocks where the terns were added to the summer feel.

Arctic tern at Balcomie

I spent an hour or so staking out the wheat fields at Old Barns, where the yellow wagtails are, to confirm breeding. They were feeding chicks, with birds regularly shuttling backwards and forwards to a bit of tramline in the middle of one of the fields. At one point I counted 4 birds above the 20 meter or so general area they kept coming back to. Yellow wagtails can nest in loose colonies sometimes so two nests this close together would not be particularly unusual. At various times I also saw two females and probably two males carrying large beakfuls of insects to the nest area and then flying away with a faecal sac each (young songbirds often present their droppings to the adult after being fed, which the adult then takes well away from the nest to keep it tidy and also inconspicuous). So fairly good evidence for two active yellow wagtail nests this year, and probably both well on the way to fledging chicks.

One of the male yellow wagtails breeding just outside Crail this year

Posted June 2, 2018 by aboutcrail in Sightings

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