Goodbye Mediterranean, Hello Baltic

Posted on Sep 2, 2013

The 2013 field season in France came to end in early August. All in all it was a good mix of hard work, stress and enjoyment. Lots of plans went awry, but as many lessons were learnt, and enough things went well to keep me busy in the office/lab over the coming months, as the nights begin to draw in.

Notable successes included 1) the recovery of 8 geolocators (with considerable help from the locals!); 2) the collection of nearly 250 tissue samples for stable isotope analysis (unfortunately not from 250 individuals); 3) the monitoring of 36 occupied but otherwise unmonitored nestboxes in Roussillon (a 500km round trip from where I was based, near Arles); 4) the collection of over 70 failed eggs of Roller, Hoopoe, Lesser Kestrel and Starling (again, this wouldn’t have happened without our collaborators in Latvia, Cyprus and Portugal) and 5) considerable refinement of methodologies for invertebrate sampling and quantification of foraging behaviour.

I was also finally able to take a satisfactory photo of a Roller, and in one day was defecated on by no fewer than 41 chicks:

Finally! A living Roller

Finally! A living Roller

Baby dinosaurs

A brood of dinosaurs

Lesson #245 - don't wear white when ringing chicks

Lesson #245 – don’t wear white when ringing chicks

Most disappointing was the failure of our PIT tag readers, however we are hopeful that with a bit of tweaking they will be up and running ready for next season!

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The weekend before last (in between a holiday on Mull, and the excellent EOU conference, hosted by my very own UEA) I visited Latvia, where the remnant (but stable) population of 20-odd pairs are being monitored by our collaborators, Edmunds Racinsksis & Ieva Mardega. As well as collecting the precious geolocators and tissue samples, kindly collected by Edmunds & Ieva while I was buys messing up in France, I was taken on a tour of the field site. Due (presumably) to agricultural intensification, Rollers are now conspicuously absent from Latvian farmland, remaining only in the pine forests and (artificially maintained) heaths of the sandy soils to the east of Riga. The forest is wonderful, with Rollers breeding in nestboxes and the odd black woodpecker cavity and foraging in the clearings created by forestry activity, around abandoned Soviet ammunition dumps and even in the forest itself. The forest is so open that you could easily drive a minibus through it – I suppose the dry sandy soil prevents an understory from developing.

Latvian pine forest

Latvian pine forest

Nestbox in the Adazi military camp

Nestbox in the Adazi military camp

The site of the most northerly known breeding Roller in Europe (excluding Russia)

The site of the most northerly known breeding Roller in Europe (excluding Russia)

Latvian pine forest

Latvian pine forest – look at all that lichen!

Due to the small, isolated nature of the Latvian population (as well as the hard work of Edmunds & Ieva) 98% of breeding Latvian Rollers were ringed as chicks in the local area. This means there is excellent data on things like age structure, as well as complete life histories of individual birds, which include records of serious (sib-sib / parent-offspring) inbreeding.

The Rollers had finished breeding by the time I arrived, but several individuals (all ringed!) were foraging in the Adazi military camp, which is 30km north of most of the breeding sites. It appears to be an important pre-migratory staging area for Latvian Rollers, and suggests that they either breed in suboptimal foraging habitat (as they are tied to a nest hole, of which there are very few in Adazi) or that the quality of foraging habitat changes over the course of the summer.

Latvian Roller a top a dead birch

Latvian Roller a top a dead birch

Juvenile Roller

Juvenile Roller

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That’s all for now, but stay tuned for results of geolocator and stable isotope analysis, as well as plans for next year.