Do birds time their reproduction based on the spring development of vegetation?

Context

The consequences of global warming can only be reliably estimated if we know how organisms respond to environmental changes. One way changes in climate and environment influence population resilience is through the modification of the seasonal timing of life-cycle events (i.e. phenology). However, species at different trophic levels usually do not respond at the same rate, and many organisms become increasingly mismatched with their food supply. In this context, central questions relate to how organisms adjust the timing of their life cycles to a changing world: Which environmental factors do they rely on to time their seasonal events like reproduction? Which components of the reproductive axis do these environmental factors influence?

Job description

The postdoc will take part in an on-going project in which we study the trophic relations between birds, insects, and vegetation. In particular, we investigate whether blue tits (Cyanistes caeruleus) use bud development of oak trees in spring to predict the peak of caterpillar abundance (i.e. the main food source for raising tits' chicks, and the main selection factor for tits' timing of breeding). This question will be addressed using a combination of experimental approaches in captivity, as well as field studies in several wild populations of blue tits that have been monitored for 20 to 40 years.

First, the successful candidate will link small-scale geographic variation in bud development of trees with variation in reproductive decisions of individual blue tits using remote-sensing imagery and field observations, and test the fitness consequences of matching the phenology of trees. Second, the postdoc will identify the main volatile components emitted by tree buds in spring. (S)he will then study whether birds are able to detect those compounds in a Y-maze apparatus, and test whether their reproductive behaviours and physiology are modulated accordingly (reproductive hormones, etc.). Third, time permitting, the postdoc might also investigate whether the influence of vegetation development on timing of breeding occurs through the ingestion, rather than the smell, of compounds present in growing tree buds, using a similar experimental approach as above.

Requirements

We are seeking a highly motivated candidate with a strong track record, who is willing to start a truly interdisciplinary study. The candidate should have interest and/or experience in behavioural ecology (behavioural tests), plant and animal physiology (tree development and avian endocrinology), spatial analyses (satellite image processing), and chemical ecology (characterization of plant volatile emissions). It is not necessary to have experience in all these fields, but the candidate should be interested in, and not afraid of, mixing these different approaches and techniques. Multi-tasking and organisational skills will be necessary and appreciated.

Location

The position will be held at the CEFE (Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175), a leading research institute in Ecology of the CNRS (Centre National de la Recherche Scientifique), situated at Montpellier, France. Montpellier has recently been ranked world second best for research in Ecology (http://www.shanghairanking.com/Shanghairanking-Subject-Rankings/ecology.html), it is thus an ideal place for studies in the field, with many opportunities to interact with forefront scientists.

Conditions of employment

This is a temporary position for two years, full-time employment. Gross salary will be of minimum 31k€ per year, which is comfortable in France.

The project and position are funded by an ANR grant (Agence Nationale de la Recherche, the main research funding agency in France).