Bonjour de France!

Today we had a foreign surprise up in Björkfjället… Johannes has been studying Dunlins around Ammarnäs since 2008. Since last year, we have been collaborating in a circumpolar project on nest predation/survival rates in sandpiper species, focussing on Dunlin. This year, this was extended with another circumpolar collaboration, which aims to map the migration route of all subspecies of Dunlin (there are quite a few, depending on your taxonomic taste).

This morning we went up to Björkfjället to deploy geolocators on three Dunlins. After I retrieved the third bird from the trap, I noticed it had a metal ring! In previous years, Johannes colour-ringed a number of adults, and metal-ringed many chicks in the preceding years. Hence, my first and only thought was ‘this must be a bird ringed as a chick by Johannes’. Little did I know… I handed the bird to Christian, who had a proper look at the ring. ‘PARIS’ it read!! Hence, this bird got his ring somewhere in France.

Dunlins colour-ringed at Ammarnäs have been resighted in, e.g., The Netherlands and Portugal, showing a south-western migration direction. In this respect, the connection with France is not very surprising. However, which stopovers individuals use for what period is not revealed by these colour-ring resightings, but will hopefully be uncovered next year… if we manage to recapture them!

Yesterday, we had great success with Red-necked Phalaropes. We recaptured two males that received a geolocator last year by Michiel, Piet and Tim. Both birds had a full year of data, showing nice tracks down to the Arabian Sea.

Ammarnäs: returning phalaropes!

Finally some news from Ammarnäs. Up until today, we had quite a ‘slow’ season. Lemming abundance has plummeted in late-winter, and thus virtually all Long-tailed Skuas are skipping this breeding season (except some weirdos far south at Kraipe and Aigert). We observed some small or medium-sized flocks of skuas that will probably make it back to sea in the coming two weeks.

Hence, our main target has been to (re)capture Red-necked Phalaropes in phalarope-city, Gelmetje. However, this didn’t went smoothly in the last week; we did find some nests, but couldn’t find any birds carrying geolocators. Nor did we find the usual ‘female-flock’ at lake Gelmetje. Deploying all available loggers therefore seemed difficult. This all changed today. While some males have been incubating for about 10 days, we now encountered a decent number of females and found a new nest of a male with logger, containing very freshly laid eggs! We didn’t manage to catch this male (yet!), but we did recapture a female with a logger it got last year by Tim, Michiel and Piet. Great!

The big surprise came only when we returned to the research station: it is one of the two females of which we already had a track! Thereby, the two years of data from this individual sheds some first light on one of the questions brought up by the paper in Journal of Avian Biology on phalarope migration. In this paper, we show that Red-necked Phalaropes usually use several areas within and adjacent to the Arabian Sea, instead of staying at a single site during the entire winter. For example, an individual may arrive in the Gulf of Oman, stay there for some time, then fly south to the spend some time along the southern Omani coast, and subsequently travel to the Gulf of Aden. These movements are presumably in response to monsoon-driven changes in where and when food is available, and the question is to what extent these movements are similar between years. Are they direct responses to local circumstances, changing from year to year, or routes learned during early life, and repeated in subsequent years? This female stayed at three distinct sites during the 2014-15 winter, but spent the entire winter in the Gulf of Aden during 2015-16, thereby showing that individuals can change itineraries between winters.

The female that returned to Gelmetje for a second year with a geolocator full of data.

Strange season at Slettnes

After five days in the field we are more and more puzzled about this season. We had the first Arctic skua chick yesterday, which is extremely early, and many more nests are about to hatch. These birds must have started laying eggs mid May! Also the Fieldfare chicks nesting near the lighthouse are about to fledge and the vegetation is two weeks ahead. At the same time many skua territories of last years are not occupied and in many territories birds are just hanging around. We also still find nests that were just started. The Red Fox is present again and indeed we found two nests predated already.

Up to now we recaptured 7 Arctic Skuas and their loggers show the wide variety we are used from them: wintering in south America, South Africa and the Caribbean. The 4 out of 7 that we recaptured last year as well, took remarkably similar routes.

Today was rainy with 6/7 Beaufort, not really weather to catch skuas. Besides we had some troubles with our catching device, the snare. It is quite ingeniously constructed around a remotely controlled vacuum cleaner spring, but now it needed some special technical attention (and a new set of batteries as it turned out later). Nevertheless we went outside to check territories at the outskirts of the area and look for Red-necked Phalarope nests. Tomorrow is going to be sunny and the day after even 15 degrees! Time for a dive in the Barents Sea!

Ammarnäs – news from the field crew

Another exciting field season in Ammarnäs started out with a lot of snow, but also a lot of rodents! This season’s team consists of Johannes Hungar, Piet Admiraal, Michiel Elderenbosch and Tim van der Meer. Coordinator Rob van Bemmelen could only stay for a week unfortunately, and in that week field conditions were not ideal.

The first few days the team got a good impression on what a good breeding season it could be for the Long-tailed Skuas. Several nests were discovered and every day more were added to the list. One of the main aims was to retrap Long-tailed Skuas with geolocators this year. Different birds had different amounts of data “on their legs” and the ones with up to four years were targeted by the team first. First captures were attempted with a snare driven by a vacuum-cleaner mechanism, an ingenious device developed by Rob.

A good year for rodents often coincides with a good year for waders. Johannes and the rest of the team found lots of nests of Golden Plovers, Redshanks and Dunlins. Tim found a Dotterel nest on his first day, and other highlights were 2 Whimbrel nests found by Piet & Michiel, another Dotterel nest and a Broad-billed Sandpiper nest found by Johannes. Several duck, Dunlin, Ruff and Red-necked Phalarope nests have also been found in the study areas. The Dotterel breeding in Gelmetje was safely caught on the nest with a walk-in trap and ringed (see its picture below). In the coming days, some of the wader nests will hatch, whereas others are predicted to hatch around the middle of July, much later than usual.

Dotterel! (Tim van der Meer)

It seems to be a lesser year for the Red-necked Phalaropes in Gelmetje. Due to the ice and snow-cover, they have started to breed late, and there seem to be less pairs than the usual ten. We have resighted two or three female phalaropes with loggers from last year, and captured one of them (see the picture below). Another ringed bird was caught, and turned out to be a female that should’ve had a logger but lost it! Unfortunately, no males with old loggers have been resighted so far.

Phalarope with new geolocator.

Long-tailed Skua nest visits and chick searches resulted in even more nests, and together with observations from Martin Green in nearby areas the highland plateaus surrounding Ammarnäs (Kraipe, Aivesjaive, Raurejaure, Gelmetje & Björkfjellet) contain at least 117 active Long-tailed Skua nests this year! A new record?

Later in the season we used a new spring trap on the nest in Raurejaure, and captured the five last geolocator-birds of this season in one day. Two birds with four years of data were caught totalling up to hopefully 12 years of data collected in captures that day! Only a few individuals have evaded our traps and will hopefully be caught in subsequent breeding seasons. In total 32 Long-tailed Skuas have been caught this year, 21 handed in their geolocator, and 25 of them received new geolocators, whereas some birds are freed of their data collecting duties.

Tim van der Meer, Michiel Elderenbosch & Piet Admiraal

Chicks, phalaropes and phalarope chicks

Like the Arctic Skuas in Slettnes, the Long-tailed Skuas in Ammarnäs are now rapidly hatching. It usually takes only a few days before all have hatched; this is strongly peaked. However, the hatching period appears to be a rather vulnerable period: in particular many one-egg clutches vanished (predated) in the last week before hatching, or – in the case of one pair in Gelmetje – both a chick and an about-to-hatch egg have been predated. Others are more lucky, such as the chick in the picture below.

A one-day old chick of a Long-tailed Skua.

We have been focusing on capturing Red-necked Phalaropes during the last days, now using mistnests to catch them. Red-necked Phalaropes are so-called uniparental, meaning that one parent is taking the lion’s share of the parental duties. In this case, that’s the male. During incubation, these guys need a break now and then to do some foraging. We found out that many males used the same pond (full of small yummy flies) as a local snackbar. Here, we managed to capture five phalaropes, two of them wearing geolocators from last year! That makes a total of four retreived loggers. Also, we lured females into mist nests (see below, the first adult females to be caught here) and we recaptured a male today that I ringed in 2010 when it was still a chick of only 4-5 grams.

Red-necked Phalarope. Definitely the hottest chick in Gelmetje.

Already a while ago Tim did a very good discovery: a nest of a Bar-tailed Godwit. Despite their big efforts for nest searching, the wader team never found one between 2008 and 2013. Sadly however, it looks like the nest is abandoned. When we checked it today, the eggs were already cold and wet.

Bar-tailed Godwit nest.

‘Sunset’ on midsummer evening at Raurejaure.

Wind, snow and some new loggers

 It has been a while since my last post. We’ve had a few camping sessions up in Raurejaure, under very chilly conditions. Hard, cold winds (~7 Bft), from time to time brightened with some snow, hail or regular showers…. Hence, not the ideal conditions for catching. Still, I managed to get two more skua geolocators, making a total of three now – all with three full tracks back and forth all the way down to the Benguela current, which is off Namibia/South-Africa. Impressive journeys!

The coming days seem to hold good weather. As the Long-tailed Skuas eggs are about to hatch,  now is the last time to easily catch adults on the nest. Hope it will work out!

We’ve read a dozen Golden Plover colour rings (have to determine the exact number yet) and a single Dunlin. With the entire wader team missing, we’ve only found very few wader nests, so I am afraid we will not get a good estimate of predation rates on wader nests for this year. We did find some in Gelmetje though; see below for one bird staying put on the nest, entirely relying on its camouflage.

There is a bird somewhere on this picture. See if you can find it!

A horrible sight: a bare-legged skua…

This looks nicer than it actually was, in terms of temperature and humidity.

Returning Red-necked Phalaropes

In the meantime, we have been catching Red-necked Phalaropes to equip them with geolocators. Red-necked Phalaropes appear to be not as site-faithful as, for example, Long-tailed Skuas, so in order to increase the chance of getting recaptures (necessary to read out the data), we only place them in ‘phalarope-heaven’. Gelmetje, that is. This is a small tundra area, squeezed in between the wet valley Marsevaggie in the west and the Vindelälven river valley in the east. It is full of small ponds, partially overgrown with floating Carex vegetation.

As you may remember from last year, we recaptured a breeding male phalarope in 2012 that was ringed at the same place in 2011 as a chick. Today, we recaptured it again, just a few hundred meters further west! It was kind enough to show us its nest while we were looking at it from about 10 meters! We also recaptured another phalarope that was captured in Gelmetje last year. This is promising, as it shows that at least some individuals return to the same area. Now lets hope they return next year with a logger full of data!

Phalaropes have webbed feet for paddling.

Phalarope count and food in the fridge!

Most of the ponds up on the tundra are still frozen. Species dependent on them are therefore still waiting for them to thaw. Among them are Red-necked Phalaropes. This is a small wader that feeds mostly swimming and winters on the ocean. There is a huge flock of phalaropes feeding (and waiting…) at the lake near the village. Today we counted little over 300 individuals! Arctic Terns were surface dipping between them. What would they be feeding on?

Arctic Tern on the ice

Up on the tundra, small arthropods start to emerge. While the snow cover is still around 80% in some parts of the study area, mainly rove beetles (Staphylinidae) increasingly are seen on the snow following air channels created by penetrating shrubs to forage on microarthropods, such as springtails (Collembola) and mites (Acari). These tiny creatures climb from the ground upwards, through little pores of the snow cristals. Higher up in the food web, waders feed on these tiny invertebrates. Maybe birds with longer bills have an advantage finding food at an early stage on the tundra where most parts are cover by snow or ice layers, probing the snow with their bill to catch the hidden invertebrates.

Temminck´s stint foraging on the snow

Lemmings did’nt crash….yet!

On the 4th of June we went up to another study area, Bjorkfjället. Still with a pretty high snow cover, we found some interesting things, as two alive lemmings!  This is a good new, because if the tundra holds some rodent numbers, skuas and owls could eventually breed. Last year was a very high lemming peak year, so it was expected a big decrease on lemming abundance this spring.

Lemming running on a snow-free patch.

During the day in Bjorkfjället we could also observe 4 female Dotterel foraging and flying by, some Dunlins, 1 Red-necked Phalarope, around 6 Golden Plover pairs, some of them behaving as if they had a nest. Finally, few Long-tailed Skuas were observed but still without any territorial behaviour.