Variation in microclimate and tree phenology

Great tits time their chick rearing with food availability in spring. If they are too early or too late, they cannot profit from the high abundance of caterpillars, which they feed to their young, therefore timing is under strong selection. Nevertheless, the birds have to anticipate this crucial period a long time before the actual event. Which cues do they use to predict if the season will be early or late? Besides ambient temperature, the phenology of trees, eg. the bud burst and leafing, has been discussed as a possible cue.

Research question
Is the timing of egg laying related to tree phenology and/or microclimate?

Possible fieldwork in the Hoge Veluwe National Park:

• Assess the variation in microclimate, eg. using temperature loggers (iButtons)
• Vegetation mapping: score the timing of leafing in different tree species
• Learn to create GIS maps and combine results of your climate, vegetation and great tit egg laying data

Duration
Spring 2009.

Interested?
Get in touch!

Contact
Sonja Schaper, e-mail: s.schaper@nioo.knaw.nl / tel.: +31 (0)26 4791 248.