Carry‐over effects in a Pacific seabird: stable isotope evidence that pre‐breeding diet quality influences reproductive success
- 9 February 2009
- journal article
- Published by Wiley in Journal of Animal Ecology
- Vol. 78 (2), 460-467
- https://doi.org/10.1111/j.1365-2656.2008.01492.x
Abstract
Summary 1. Understanding the interactions between different periods of the annual cycle in migratory animals has been constrained by our inability to track individuals across seasons. In seabirds, virtually nothing is known about how diet quality during the non-breeding period, away from the breeding grounds, might influence subsequent reproductive success. 2. We used stable nitrogen ( δ 15 N) and carbon ( δ 13 C) isotopes to evaluate the effects of non-breeding diet quality on the timing of breeding and egg size in a population of Cassin's auklets ( Ptychoramphus aleuticus ) breeding on Triangle Island, British Columbia. Adult feathers are grown during two different periods of the annual cycle, which allowed us to estimate diet quality from the previous fall (October-November) and pre-breeding (February-March) period. 3. We found that the estimated proportion of energetically superior copepods ( Neocalanus spp.) in the pre-breeding diet tended to be higher in females that bred earlier and laid larger eggs, whereas energetically poor juvenile rockfish ( Sebastes spp.) were dominant in the pre-breeding diets of females that bred later and laid smaller eggs. We detected no effect of fall diet quality on breeding date or egg size, and no effect of pre-breeding diet quality on breeding date in males. 4. Pre-breeding diet quality was not related to body condition measured 1-2 days after laying, which suggests that females may need to attain a threshold condition before they initiate breeding and successfully rear young. 5. Our results suggest that changes in climatic conditions during the pre-breeding period may have severe consequences for reproductive success by influencing breeding date and egg size. Our work emphasizes the importance of determining how events are linked throughout the annual cycle for understanding the fitness and population dynamics of migratory animals.Keywords
This publication has 65 references indexed in Scilit:
- Winter feeding of birds increases productivity in the subsequent breeding seasonBiology Letters, 2008
- Responding to environmental change: plastic responses vary little in a synchronous breederProceedings. Biological sciences, 2006
- Linking nitrogen dynamics to climate variability off central California: a 51 year record based on 15N/14N in CalCOFI zooplanktonDeep Sea Research Part II: Topical Studies in Oceanography, 2003
- Factors That Influence Assimilation Rates and Fractionation of Nitrogen and Carbon Stable Isotopes in Avian Blood and FeathersPhysiological and Biochemical Zoology, 2002
- Inter-annual variation in the diet, provisioning and growth of Cassin's auklet at Triangle Island, British Columbia: responses to variation in ocean climateMarine Ecology Progress Series, 2002
- Recent changes in the winter diet of murres (Uria spp.) in coastal Newfoundland watersCanadian Journal of Zoology, 2000
- Dynamics of food availability, body condition and physiological stress response in breeding Black‐legged KittiwakesFunctional Ecology, 1999
- Variation in the diet of Cassin's auklet reveals spatial, seasonal, and decadal occurrence patterns of euphausiids off California, USAMarine Ecology Progress Series, 1996
- Seasonal Cycle of Zooplankton off Southwestern British Columbia: 1979–89Canadian Journal of Fisheries and Aquatic Sciences, 1992
- The importance of plankton to Cassin's auklets during breedingJournal of Plankton Research, 1981