Data from: Male breeding experience, not mate familiarity, affects reproductive output in black brant geese

Individuals in species with long-term social monogamy often incur fitness costs after mate change. We evaluated the relative contributions of mate familiarity and male breeding experience to the costs of mate change of female black brant geese (Branta bernicla nigricans). We assessed the effects of mate change on relative nest initiation date, clutch size, brood size at hatch, growth rates of goslings, and prefledging survival of offspring. We modeled variation in relative nest initiation dates, clutch size, initial brood size, and gosling growth rates using generalized linear mixed models in Program R. We estimated prefledging survival with Cormack-Jolly-Seber models in Program MARK using reencounters of webtagged goslings. Mate change had a small effect on relative nest initiation date, clutch size, and initial brood size, but no effect on growth rates of brant goslings. Females breeding with an unfamiliar, but experienced male had goslings with higher prefledging survival rates (ϕ = 0.44 ± 0.10 [95% CI]) than those breeding with a familiar, experienced mate (ϕ = 0.30 ± 0.04). However, females that changed mates and re-paired with an inexperienced male had goslings with substantially lower prefledging survival rates (ϕ = 0.20 ± 0.04) than any other group of females. Our findings indicate that reproductive output by female brant is affected by male experience rather than mate familiarity. We believe that female brant typically benefit from mate retention, because most will not acquire an experienced partner after mate change.

实行长期社会单配制的物种个体，在更换配偶后通常会面临适合度成本。本研究针对雌性黑雁（Branta bernicla nigricans），评估了配偶熟悉度与雄性繁殖经验对其更换配偶所产生成本的相对贡献。我们评估了更换配偶对以下指标的影响：相对筑巢起始日期、窝卵数、孵化时雏鸟窝数、雏鸟生长速率以及后代的出飞前存活率。我们借助R程序（Program R）中的广义线性混合模型（generalized linear mixed models），对相对筑巢起始日期、窝卵数、初始雏鸟窝数以及雏鸟生长速率的变异进行建模。我们通过对带有脚旗标记的雏雁的重捕数据，借助MARK程序（Program MARK）中的科马克-乔利-西伯模型（Cormack-Jolly-Seber models）估算出飞前存活率。更换配偶对相对筑巢起始日期、窝卵数以及初始雏鸟窝数仅存在微弱影响，但对黑雁雏鸟的生长速率无显著作用。与不熟悉但繁殖经验丰富的雄性配对繁殖的雌性，其雏鸟的出飞前存活率（ϕ = 0.44 ± 0.10 [95%置信区间]）高于与熟悉且经验丰富的配偶配对的雌性（ϕ = 0.30 ± 0.04）。然而，更换配偶后与繁殖经验匮乏的雄性重新配对的雌性，其雏鸟的出飞前存活率（ϕ = 0.20 ± 0.04）显著低于其他所有雌性组。本研究结果表明，雌性黑雁的繁殖输出受雄性繁殖经验的影响，而非配偶熟悉度。我们认为，雌性黑雁通常会从保留原有配偶中获益，因为多数个体在更换配偶后无法获得经验丰富的配对对象。