New paper on ecology of Golden plover chicks

Machín et al. 2017

We are very happy to share with you the publication of our last paper: “Habitat selection, diet and food availability of European Golden Plover Pluvialis apricaria chicks in Swedish Lapland”. It has been a long way but it is finally here!! Click here!

This study shows the prey preferences of Golden plover chicks in the alpine tundra in northern Sweden, as well as their habitat use and food availability. Interestingly, a peak of bibios (Bibionidae, also known as marsh flies) at the end of the season in 2011, made the chicks change their diet to practically only feed on them, so we highlight the importance of this seasonal effects on the food availability, ergo diet, survival and growth of the chicks. We also show that plovers in Lapland do not have Tipulids (Crane Flies) as their favorite prey, as it happens to be in another population (UK), where chicks rely on them.

We are recently working on the second part of this story, analysing which factors influence the growth of the chicks. Hope to show it to you soon!

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20/20

Yesterday we mounted the final geolocator on a Red-necked Phalarope! We fitted 20 in total: 13 on males and 7 on females. Upon approaching the 20, it became increasingly difficult to find and capture new ones. Females have left by now, and the only two breeding males in the area that didn’t have a logger yet occupied extremely wet and inaccessible areas. Although I went into the marshy ponds as far as possible (wearing only shorts…), they won the game! Yesterday, there was suddenly a group of five males in the ‘big’ lake of Gelmetje; probably failed breeders. We captured three of them and surprisingly, one of them was already ringed as a chick in 2013 by Johannes. This adds to a growing number of recaptures of birds ringed as chicks in the same area.

Skua-wise the work is rather ‘stable’: we are checking the few chicks that are still around. We monitor their growth and in return they get some jewelry (a steel ring and a green colour ring). In Raurejaure we have only four chicks left, and singletons are in Gelmetje and Björkfjället. They are getting bigger and bigger and are around 200 grams already. Juvenile feathers are emerging but the wings are still stubby. See below for one of these beauties!

Long-tailed Skua chick. Higher mountains of Ammarfjället in the background.
Fluffy Long-tailed Skua chick on the 1st of July. Higher mountains of Ammarfjället in the background.
One of the succesfull pairs: KM and NR, keeping an eye on their chick and us. Lake Geppejaure in the background.
One of the succesfull pairs: KM and NR, keeping an eye on their chick and us. Lake Geppejaure in the background.
Chick time! Familiair to regular guests of this blog: a Golden Plover.
Chick time! Familiar to regular guests of this blog: a Golden Plover. My girlfriend Denise found it on her first day in the field!
We had some encounters with Caipercaillie chicks chaperoned by their protective mothers. Big mamas!
We had some encounters with Caipercaillie chicks chaperoned by their protective mothers, mainly along the gravel road towards Gelmetje and Björkfjället. Big mamas! Yesterday, we had two families, a male Hazel Grouse and an immature Moose male. Other goodies these days include the occasional Golden Eagle, Ring Ouzels and quite some Bohemian Waxwings. We even found a nest of the latter!

keratin producers

Feathers are made up of keratin, a very strong protein also present in our hair and nails. Only covered by down in their first days after hatching, Golden Plover chicks produce thousands of new feathers during the pre-fledging period.

Contour feathers will cover their body to help thermal insulation and waterproofing, and finally wing feathers will give them the power to fly.

Juvenile Golden Plovers are very easy to recognise in the field. With fresh golden feathers on back and wings, lacking dark belly and face tipical from breeding adult plumage. However, once adult birds moult into winter plumage, the differences are almost imposible to detect.

A 18 days-old (left) and 25 days-old chick (right)
A 18 days-old (left) and an almost fledged 25 days-old chick (right)

Ground-dwelling arthropod abundance has dropped in the last days. However, berries are starting to mature and Golden Plover chicks will defenitely go for them. Moreover, with their now longer bills they will increase their feeding range, probing under the soil surface in search of larvae and other hidden invertebrates.

A crane fly (tipulidae) sheltered from the wind
A crane fly (tipulidae) sheltered from the wind