Habitat preference facilitates successful early breeding in an open-cup nesting songbird

Selecting breeding habitats that ameliorate environmental limits on fitness and facilitate successful reproduction should benefit individual animals. This is particularly true in the temperate zone, where breeding early in a season presents a unique series of environmental challenges that can limit an individual's fitness. While many studies document links between habitat quality and reproductive success, few identify the cues used to assess habitat quality or the components of reproduction most influenced by occupying higher quality habitat, particularly during the early breeding season. We used detailed spatial maps and observations of all early season nesting attempts in an insular song sparrow (Melospiza melodia) population over 38 years to estimate the influence of nest-site preference on reproductive success and to test whether relative microclimate or food availability may act as cues for early season site selection. Female sparrows in preferred early season nest sites had earlie...选择能够缓解环境对个体适合度的制约、并助力成功繁殖的繁殖栖息地，将使动物个体获益匪浅。这一点在温带地区尤为突出：季内早期繁殖会遭遇一系列独特的环境挑战，这些挑战会制约个体的适合度。尽管已有大量研究证实了栖息地质量与繁殖成功率之间的关联，但鲜有研究明确动物用以评估栖息地质量的线索，以及占据高质量栖息地对繁殖各环节的具体影响——尤其在繁殖早期阶段。本研究依托38年间对某岛屿歌带鹀（Melospiza melodia）种群所有季内早期筑巢尝试的详细空间图谱与观测数据，旨在评估巢址偏好对繁殖成功率的影响，并检验相对微气候或食物可得性是否可作为早期繁殖季巢址选择的线索。在受偏好的早期繁殖季巢址中的雌歌带鹀，其（原文内容未完整显示）