Reproductive strategies in the common sandpiper (Actitis hypoleucos)
Shorebirds (Order Charadriiformes) exhibit a wide range of mating and parental care systems from apparently monogamous biparental care through to polygamous uniparental care. In addition, sex-role reversal, where male-biased parental care and female desertion predominate, appears to have arisen independently a number of times. This diversity makes shorebirds an ideal group in which to investigate the evolution of mating and parental care strategies.
In 1998 I began a study of the Common Sandpiper Actitis hypoleucos, a migratory shorebird which breeds throughout the northern Palaearctic. The species is unusual among Palaearctic shorebirds in that pairs establish and defend well-defined linear territories within which they nest and forage (most other breeding shorebirds forage extra-territorially). Mate choice decisions may therefore be based on the quality of the resources within the territory, variable traits of potential mates which may signal mate quality, or a combination of both.
The study population is located on a tributary of the River Tweed in south-eastern Scotland. Adults are relatively easy to trap and observe, making the Common Sandpiper an ideal study species in which to investigate:
- territory quality and its influence on the order of territory acquisition and mating decisins
- sex roles in parental care and brood desertion
- mating strategies
To date I have used multilocus DNA fingerprinting and PCR-based techniques to determine:
- the prevalence of alternative mating strategies (such as the level of extra-pair paternity)
- the sex-ratio (to investigate the possibility of faculatative manipulation of the brood sex-ratio)
I plan to use these novel findings to help explain the differences in the sex roles and variatin in fitness between individuals.
The study is funded by the Natural Environment Research Council (http://www.nerc.ac.uk) and the CASE partner, Scottish Natural Heritage (http://www.snh.org.uk)
Allan Mee (email@example.com)