My colleagues and I (Simone Vincenzi, Scott Hatch, Thomas Merkling, Alexander S. Kitaysky) recently published the paper "Carry-over effects of food supplementation on recruitment and breeding performance of long-lived seabirds" in the Proceedings of the Royal Society Biological Sciences (you can find the un-gated paper here).
It has been a long and challenging work, from data preparation to multiple manuscript revision, but it has been worthwhile, as results are of general interest and intriguing.
From the Cover Letter we sent to PRSB's Editor: "This is the first experimental test of the long-term effects of controlled variation in early food availability in long-lived wild animals. In addition to casting light on some of the ecological consequences of variation in early food availability, our results also have pivotal consequences for conservation science".
------ Some other excerpts from the cover letter here below
The supplementation of food for wild animals is extensively applied as a conservation tool to increase the local production of young, but the effects of such food supplementation on the subsequent recruitment of long-lived animals into natal populations are largely unknown. For long-lived species, studies are generally observational due to the long time periods required for individuals to reproduce and/or complete their life cycles (SV note: I am lucky enough to work on two model system with tagging that started in both cases in 1996). Our experimental study, more than a decade long, of the long-term effects of early food supplementation on long-term performance of a long-lived species is thus a novel, original, and exciting contribution. We used the unique experimental system of kittiwakes breeding on Middleton Island (Alaska) to test the alternative hypotheses that food supplementation early in life (a) increases overall fitness of birds, or (b) delays viability selection, with no consequences for the long-term dynamics of the species.
The results of our study are exciting and surprising. Through rigorous statistical and modeling analyses, we found that delayed viability selection is decreasing the recruitment rate of food-supplemented chicks with respect to control birds. We also identified a potential mechanism for the delayed viability selection, i.e. more intensive brood reduction in control nests.Lifetime reproductive success of a subset of kittiwakes that thus far had completed their life cycle was not affected by the food supplementation during development. However, per-nest contribution of recruits was still higher for food-supplemented nests due to their greater productivity compared to control nests, thus suggesting a positive net effect of food supplementation on recruitment.
The paper received media coverage on ScienceNews with a very clear and accurate article written by Sarah Zielinski in the Wild Things blog.
Boring, but important, note (as we all know that talk is cheap, but money buys whiskey) about funding:
Fieldwork and modeling were supported by the US Geological Survey and North Pacific Research Board (Project no. 320, BESTBSIERP Projects B74, B67 and B77). S.V. is supported by an IOF Marie Curie Fellowship FP7-PEOPLE-2011-IOF for the project ‘RAPIDEVO’ on rapid evolutionary responses to climate change in natural populations, and by the Center for Stock Assessment Research (CSTAR). The MC Fellowship FP7-PEOPLE-2011-IOF and the Institute of Arctic Biology at UAF provided funds to cover the publication costs.