One of the highlights of the breeding season at Stora Karlsö is when the common murre chicks fledge and take to the sea in spectacular fashion: by jumping from their cliff nests to the beach below! We are now in the middle of the chick jumping period and therefore the end of the field season. The chick jumping is a bit of an event in Sweden and this year Swedish television (SVT) was here to film two programmes about it. So tune in to ‘Mitt I Naturen’ and ‘Djur med Julia’ to see the chicks in action!
But before I sign off for the season with cute pictures of chicks and suchlike, an update on the telemetry. As we have been able to recapture 4 (!) razorbills this season with time-depth recorder devices on them, we have been able to deploy 6 such devices on murres, with the intention of recapturing them next season and get both breeding season and over-wintering dive data.
|Common murre with TDR device attached, ready to be released.|
We have also deployed 15 GPS devices on the murres and retrieved 12, a very respectable recapture proportion. Fortuitously we have some tracks from when a storm hit the area and there is evidence for the murres moving to avoid the worst of it.
|Bird recaptured and picture taken just prior to removing the GPS, thereby ending a three-day long deployment.|
Overall, it’s been a good telemetry season, especially as regards recapture of razorbills from last year. Now it’s on to analyzing all the great data!
Finally, as promised, a picture from the ringing of murre chicks as they fledge on the beach. We take mass, as well as some feathers, and give them both a plastic and metal ring. Then we release them and hope they make it to their fathers waiting for them close to shore. And then of course we hope to read their rings again next year when they return as juveniles!
Me holding a newly ringed and weighed murre chick. Notice the realistic stains on its front, the price for cliff-nesting with lots of other birds!
Of course the murre chicks are not alone on the island, there are lots of other (cute) chicks to be seen this time of year. Easiest to see as a researcher in the artificial ledge (built in 2009 to study murres) are razorbill chicks that are hatching now and will fledge in a few weeks time, mostly after the murres are done. Since 2015 a few razorbills breed on the ledge and as of July 1 this year, we have a razorbill chick! This is exciting news as razorbills are more challenging to study (breeding mostly under boulders and rocks on Karlsö), and this opens a whole new suite of possibilities for research on this more enigmatic species.
The obligatory razorbill chick picture from inside the artificial ledge (aka Auk Lab). At this stage (a day old) they are still light grey/white, but will look a lot more like the adults by the time they fledge.
And now all that remains is to sign off for this year! It’s been productive and busy, as it should be, and hopefully we will have gathered exciting data that will soon see the light of day in new papers. Until then, see you around!
|The capture-and-handle adult murres team! From left to right: Natalie Isaksson (Lund University), Tom Evans (Lund University), Rebecca Young (Baltic Seabird Project).|