Effect of feeding rates before egg laying on the timing of reproduction in the great tit

Natural selection favours early breeding in great tits. In general, great tits are breeding too late. Why are they not breeding earlier? Earlier breeding means laying eggs during less favourable conditions. Because egg production is very costly, great tits might be energetically restricted to lay their eggs earlier. Conditions during the period before egg laying are very important for the timing of egg laying, however, almost nothing is known about what female great tits are actually doing during this period of year!

Using radio tracking devices, we will follow individual female great tits in the period before egg laying (March - April). We will score where (location, tree species, location within the tree) they are, what they feed on and how succesfull they are foraging. Additionally, we will measure food availability during this period using various sampling methods. All field work will be carried out in National Park the Hoge Veluwe.

Research questions

• What are the main food sources for female great tits?
• What affects the availability of these food sources?
• Do all females use the same food sources?
• Is individual feeding rate related to the timing of egg laying?
• (any of your own questions that we can analyse with these data)

Contact
Interested? Contact Luc te Marvelde, e-mail: l.temarvelde@nioo.knaw.nl / tel.: +31 (0)26 4791 247.