Fitness-related consequences of relaying in an arctic seabird: Survival ofoffspring to recruitment age

Authors
Citation
Jm. Hipfner, Fitness-related consequences of relaying in an arctic seabird: Survival ofoffspring to recruitment age, AUK, 118(4), 2001, pp. 1076-1080
Citations number
30
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Animal Sciences
Journal title
AUK
ISSN journal
0004-8038 → ACNP
Volume
118
Issue
4
Year of publication
2001
Pages
1076 - 1080
Database
ISI
SICI code
0004-8038(200110)118:4<1076:FCORIA>2.0.ZU;2-O
Abstract
Seasonal declines in rates of renesting following clutch loss are common fe atures of avian brooding, and are generally thought to reflect underlying s easonal declines in food availability that lower survival prospects for lat e-season offspring. However, in Thick-billed Murres (Uria lomvia), long-liv ed Arctic seabirds that lays a single-egg clutch, previous research has sho wn that early laying females will continue to relay until late in the layin g period. Moreover, hatching success is similar between first and replaceme nt attempts, as are nestling growth and survival, when parental quality is controlled. I compared survival between departure from the breeding site an d recruitment age (4-5 years) for Thick-billed Murres that hatched from fir st and replacement eggs, but that were raised by parents that laid their fi rst eggs early in the season. Replacement-egg offspring hatched and departe d the colony about three weeks later than did first-egg offspring,but despi te that, they were no less likely to survive to recruitment age. That resul t indicates that the potential fitness payoff from a replacement egg is sim ilar to that from a first egg for the more capable members of the populatio n. I suggest that an adequate and predictable late-season food supply ultim ately underlies the considerable relaying capacity exhibited by Thick-bille d Murres.