Nest and brood stage association between ducks and small colonial gulls in boreal wetlands

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Plasticity in timing of avian breeding in response to spring temperature differs between early and late nesting species

Plasticity for breeding dates may influence population vulnerability to climate change via phenological mismatch between an organism’s life cycle requirements and resource availability in occupied environments. Some life history traits may constrain plasticity, however there have been remarkably few comparisons of how closely-related species, differing in key traits, respond to common phenology gradients. We compared population- and individual-level plasticity in clutch initiation dates (CID) in response to spring temperature among five duck species with early- to late-season nesting life histories. Plasticity was strongest in females of the earliest breeding species (common goldeneye [Bucephala clangula], mallard [Anas platyrhynchos], and gadwall [Mareca strepera]), whereas late-nesting lesser scaup (Aythya affinis) and white-winged scoter (Melanitta fusca deglandi) did not respond. These results contrast with previous work in other bird families that suggested late-breeders are generally more flexible. Nevertheless, late-breeding species exhibited annual variation in mean CID, suggesting response to other environmental factors unrelated to spring temperature. Goldeneye and gadwall females varied in their strength of individual plasticity (‘individual × environment’ interactions) and goldeneye and scoter females showed evidence of interannual repeatability of CID. Fitness consequences of CID plasticity in response to spring phenology, including trophic mechanisms and population consequences, warrant investigation

Spring phenology and timing of breeding in short-distance migrant birds: phenotypic responses and offspring recruitment patterns in common goldeneyes

Understanding how organisms adjust breeding dates to exploit resources that aff ect fi tness can provide insights into impacts of climate change on avian demography. For instance, mismatches have been reported in long-distance migrant bird species when environmental cues experienced during spring migration are decoupled from conditions on breeding grounds. Short-distance migrant bird species that store reproductive nutrients prior to breeding may avoid or buff er adverse phenological eff ects. Furthermore, reduced short-term reproductive success could be off set by higher future recruitment of surviving off spring. We evaluated whether recruitment of locally-hatched female off spring was related to hatching date alone or strength of mismatched breeding date for 405 individually-marked adult female common goldeneyes Bucephala clangula (a short-distance migrant) and their ducklings from a site in central Finland where ice-out date has advanced by ~2 weeks over 24 yr. Path analyses revealed that older, early-nesting females with good body condition and larger broods recruited the most female off spring. Off spring recruitment decreased strongly among females that bred late relative to other females in the population each year; the extent of mismatched breeding date, i.e. hatching date scaled to annual ice-out date, was less infl uential. Overall, most females advanced breeding dates when ice-out occurred earlier in spring, but some females exhibited greater fl exibility in response to ice-out conditions than did others. In general, directional selection favoured early breeding over a wide range of ice-out dates. Our results seem most consistent with a hypothesis that some short-distance migrant species like goldeneyes have the capacity to track and respond appropriately to changing environmental conditions prior to onset of breeding

Nest and brood stage association with ducks and small colonial gulls in boreal wetlands

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Hotspots in the environment - long-distance attraction of goldeneye broods to a man-made pond

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Do environmental conditions experienced in early life affect recruitment age and performance at fi rst breeding in common goldeneye females?

Environmental conditions experienced early in life may have long-term impacts on life history traits and reproductive performance. We investigated whether ambient temperature experienced during the first two to four weeks of life and weather severity during the first two winters affected recruitment age and relative timing of breeding in the year of recruitment in female common goldeneyes Bucephala clangula. Our sample consisted of 141 female recruits hatched in a study population in central Finland between 1985 and 2013 and captured later as breeders. About 56% of the recruited females bred for the first time when two years old (range 2–6 yr). Individuals facing colder ambient temperatures during the first two to four weeks posthatch or more severe winter conditions during the first two winters did not recruit at an older age. Nor did maternal characteristics, relative hatch date or nest site availability affect recruitment age. For females that recruited at two years old, the date of first breeding was usually late relative to the population mean that year (mean difference 6.9 d, range –7 to 21 d). Our results suggest developmental buffering enables female goldeneye ducklings to mitigate the impacts of adverse environmental conditions experienced during the first weeks of life, at least in terms of first breeding.201

Environmental conditions in early life, recruitment age and performance at first breeding in common goldeneye females

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Data from: Do environmental conditions experienced in early life affect recruitment age and performance at first breeding in common goldeneye females?

Environmental conditions experienced early in life may have long-term impacts on life history traits and reproductive performance. We investigated whether ambient temperature experienced during the first two to four weeks of life and weather severity during the first two winters affected recruitment age and relative timing of breeding in the year of recruitment in female common goldeneyes (Bucephala clangula). Our sample consisted of 141 female recruits hatched in a study population in central Finland between 1985 and 2013 and captured later as breeders. About 56% of the recruited females bred for the first time when 2 years old (range 2-6 years). Individuals facing colder ambient temperatures during the first two to four weeks posthatch or more severe winter conditions during the first two winters did not recruit at an older age. Nor did maternal characteristics, relative hatch date or nest site availability affect recruitment age. For females that recruited at 2 years old, the date of first breeding was usually late relative to the population mean that year (mean difference 6.9 days, range -7 to 21 days). Our results suggest developmental buffering enables female goldeneye ducklings to mitigate the impacts of adverse environmental conditions experienced during the first weeks of life, at least in terms of first breeding