2016-11-15

Along the longest of ways. Tracking 10 gram songbirds from eastern Siberia to southern Africa



Adult male willow warbler
Willow warbler (Phylloscopus trochilus) is the most common breeding bird species in Sweden. Globally its distribution range spans from coast of Atlantic to Pacific ocean. Species is currently split in three subspecies mainly due to differences in migration behaviour. North Scandinavian P. t. acredula migrates SSW to east Africa, central European/southern Scandinavian P. t. trochilus migrates SSE to western Africa. Far NE P. t. yakutensis hypothetically migrate SWS to southern Africa. This might be longest passerine migration on planet.
 
Me in the field with freshly caught dusky warbler female (Phyllsocopus fuscatus)
June and July this summer I spent on expedition to Chaun field station in arctic Russia (68.81 N, 170.62 E). I collected blood and feather samples as well as morphological measurements, phenotype data and some ecological information (clutch size, phenology, breeding density) of P.t.yakutensis breeding there. Importantly I fitted 28 geolocators on adult male willow warblers who were breeding in Chaun delta. Next year I will return to very same study site and try to find returning birds and hopefully document this remarkable migratory trip. Many thanks to Prof. Staffan Bensch, Prof, Susanne Åkesson and Dr Diana Solovyeva for making this project possible.


Researchers and students at Chaun field station, summer 2016. From Left to right: Ksenija Alehina, Anastasija Mylnikova, Carly Stransky, Darya Barykina , Tatjana Stepanova, Dr. Diana Solovyeva (director of the station), Prof. Chao Lei, Gleb Danilovich, Kristaps Sokolovskis, Dr. Sergey Vartanyan, Nikolai Lane

 

Typical willow warbler breeding habitat in Chaun river delta.

Comparison of willow warbler subspecies. From left to right: yakutensis, acredula, acredula and trochilus hybrid, trochilus. Yakutensis is alive and was gently placed on back to take this picture before reliesing. Others are stuffed dummies used as reference specimens to score phenotype.

Adult male willow warbler with geolocator
//Kristaps Sokolovskis

2016-10-13

The next move!


Our mobile tracking radar station has been on the move again. It was transported from temporary storage at Ljungbyhed airfield to a long term deployment at Stensoffa ecological research station outside of Lund. There it will be easy for us to access it for maintenance and upkeep, but it will also be operational and possible to use in future projects. The transport went smoothly, and the trucking company we use can claim a real expertise in moving radar equipment by now!



/Cecilia

Earlier blog post about the radar field projects:
1(3) Preparing the radar for a new field season!
2(3) Radar calibration field campaign
3(3) Bringing home the radar


2016-09-29

Getting the IgNobel Prize!

It has been a great experience to receive the IgNobel prize, which makes people laugh and then think. The prize highlights the innovative and improbable research, and promote scientists thinking out of the box. I am happy to now belong to this community of scientists combining partly humor with research.
The last few days I have shared many laughs and new insights with my fellow Prize Winners. To be part of the whole event has been great and I have learned much about, for example, personalities of rocks, lies, badger life, and itching arms seen in mirrors. The project we won the prize for, how horseflies find the black but not white horses, a project I have pursued togethter with Gabor Horváth and his hungarian reasearch team received much attention and interest from the audience at the afternoon talks at MIT, Cambridge where the IgNobel Prize winners were lecturing 24 September.   

I truly recomend to catch up with more improbable research at the IgNobel homepage.

The Prize.

...and the Prize money.

 Our research has been summarized by a short film by Lund University.


/Susanne

More info from Lund University

2016-08-25

The great flights of great snipes: fact or fantasy?


By using geo-locators we have in recent years been able to reveal a most spectacular migratory behaviour, that of the great snipe. In late August, males of this medium-sized wader bird leave their breeding grounds in central Sweden and embark on a long and fast direct flight to sub-Saharan Africa. They then fly on average 5500 km in 2½ days, at an average speed of about 90 km/h. One individual was estimated to have flown 6900 km over 2½ days, at a speed of 115 km/h.
The combination of distance and speed seems to be a “world record” among migrating animals and when the first paper was published in 2011 it received a lot of media attention. Apparently, the great flights have now also reached the fantasy genre. In “The Magician’s Land”, a fantasy novel from 2014 by Lev Grossman, some of the characters want to transform themselves to migrating animals, to be able to reach Antarctica. One suggestion is they should turn into great snipes (!) and then the amazing capacity of these birds is referred to in quite some detail. 
It is nice to see how the wonders of nature can fit so well into a fantasy novel. Facts from nature just as they are. But given that “The Magician’s Land” is a real best-seller, and therefore is read by many more people than our original paper in Biology Letters, maybe there is a risk that the great snipe flights may soon be considered more fantasy than facts? (-:
“- I have heard that great snipes fly thousands of km in just a few days”.
“- Come on, that’s just something written in a fantasy novel!

//Åke Lindström
(Thanks to Phil Battley for informing us about the fantasy world!)

Read more in:
Klaassen, R. H. G., Alerstam, T., Carlsson, P., Fox, J. W. & Lindström, Å. 2011. Great flights by Great Snipes: long and fast non-stop migration over benign habitats. – Biol. Lett. 7:833–835.
Lindström, Å., Alerstam, T., Bahlenberg, P., Ekblom, R., Fox, J. W., Råghall, J. & Klaassen, R. H. G. 2016. The migration of the great snipe Gallinago media: intriguing variations on a grand theme. – J. Avian Biol. 47:321–334.

2016-08-18

From Ottenby to Abisko (2:2)



View over the breeding area from the helicopter on June 15.
After one month of fieldwork at Lake Latnjajaure the field season is now over for my part. The aim has been to catch Common Ringed Plover to retrieve light level geolocators and deploy new ones. Earlier this spring I was also catching plovers at Ottenby on Öland, which I wrote about in a previous post. The purpose for this study is to gain more knowledge about different migration strategies between populations breeding and wintering at different latitudes.

Snowfall is not uncommon in mid June.
When I left Ottenby in the beginning of June spring had passed on to summer, so it was a treat to experiencing spring a second time up north. This was my third visit to Latnjajaure since 2014 and as usual the work started off in a wintery landscape. Most of the breeding ground for the Common Ringed Plovers was covered by snow. However, from the helicopter, on the way towards the site, it was easy to spot where the nests will be laid. The only bare spots in mid June when the birds just have arrived or only ben present for a week are located on end-moraines. These are subjected to heavy wind erosion and it is there most nests will be laid.

One of the Ringed Plovers with Lake Latnjajaure in the background.
It took only a short walk around the field hut to locate two of seven birds that were equipped with geolocators last year. After a couple of more days four had been spotted and after an additional week the first active nest were found. That particular nest or rather “scrape” (Ringed Plovers digs a little hole in the ground which they only “decorate” with pebbles) had been used three consecutive years by the same male. In addition, the first two years he was breeding with the same female! This year they had divorced, but the female were still in the area. More precisely 300 meters away, in a new nest with a new male. During the following days three more nest were found. In total 4 out of 7 individuals with geolocators returned this year, which is a 57 % return rate. This is as high as the estimated return rate for birds without loggers.
 
Juliana is placing out a walk in trap.
On the 29th of June Juliana Dänhardt joined me for the trapping. The first three birds were rather easy to catch, but one male repeatedly refused to walk into the walk-in-trap. After trying several times a day for a week we were close to give up. But late in the evening the day before heading home we succeeded. Actually, it was the fastest catch I ever had only taking three minutes after placing out the trap.

Now I am looking forward to start analysing the 4 loggers from Lake Latnjajaure and the in total 8 from Ottenby (where two might include up two years of data). This sums up to a successful field season and gives great hopes for next year!


 //Linus Hedh

2016-08-09

Successful breeding of common swifts in Swedish Lapland

This year’s field work in northern Swedish Lapland revealed a successful breeding year, as the spring and summer weather was much warmer providing better feeding conditions and more aerial insects for the common swifts than the previous year. The nest boxes made out of natural spruce stems, and set up in gardens and safe places provide new and good breeding sites as the natural breeding sites in old pine trees in the forests has largely decreased due to heavy logging. Kind local people caring for the swifts set up the boxes and make sure they are protected against wear and damage. It is obvious, however, that there is an urgent need to spare old pine trees and trees with woodpecker holes in order to provide natural nest sites for the common swifts and other birds by the forest industry. This year was spectacular as we were able to catch an individual breeding swift which had escaped our nets in the last two years. It all happened when we caught swifts in the last evening. The even better news was that the individual carrying the logger was in great shape and had three well-fed young in the nest. Three-egg clutches are uncommon in the northern breeding range.

Susanne Åkesson

2016-07-24

Time to Jump! (2:2)


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).
   
/Natalie
Photo’s: Natalie