The effects of harvest on cooperatively breeding species are often more complex than simply subtracting the number of animals that died from the group count. Changes in demographic rates, particularly dispersal, could offset some effects of harvest mortality in groups but this is rarely explored with cooperative breeders. We asked whether a cooperatively breeding species known for long‐distance dispersal could compensate for the effect of harvest mortality on density by adopting immigrants into the group. We used genetic samples to estimate the minimum density of gray wolves (Canis lupus) and proportion of immigrants in groups in the northern US Rocky Mountains after an annual harvest regime was initiated and in the Canadian Rocky Mountains where wolves were managed consistently under an annual harvest regime. We tested whether immigration (1) compensated, (2) partially compensated or (3) did not compensate numerically for harvest mortality in groups and hypothesized immigration would increase with increasing harvest intensity. Density of wolves in groups declined after harvest was initiated whereas immigration into groups was consistently low and did not change with harvest in the US study area. Immigration into groups was similarly low and density even lower in the Canadian study area compared to the US study area. Our results indicate immigration did not compensate for harvest mortality in groups in two separate populations of a cooperatively breeding carnivore. We hypothesize the social structure of wolf groups may limit the potentially compensatory response of immigration in some populations.

中文翻译：

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移民并不能抵消合作繁殖的食肉动物群体的收成死亡率

收获对合作繁殖物种的影响通常比简单地从群体数中减去死亡的动物数量更为复杂。人口变化率的变化，尤其是人口分布的变化，可能会抵消群体死亡率的某些影响，但是合作育种者很少对此进行探讨。我们询问以远距离传播闻名的合作育种是否可以通过将移民引入该群体来补偿收获死亡率对密度的影响。我们使用基因样本来估计灰狼的最小密度（狼）和在实行年度收割制度后在美国洛矶山脉北部以及在每年收割制度下对狼进行统一管理的加拿大落基山脉中成群移民的比例。我们测试了移民（1）是否得到补偿，（2）部分得到补偿或（3）没有对群体的收获死亡率进行数值补偿，并且假设的移民会随着收获强度的增加而增加。开始采集后，各组中狼的密度下降，而在美国研究区域，成组的迁徙一直很低，并且没有随收获而变化。与美国研究区相比，加拿大研究区的成群移民同样低，密度甚至更低。我们的结果表明，在合作繁殖的食肉动物的两个单独种群中，移民并不能弥补群体中的收获死亡率。我们假设狼群的社会结构可能会限制某些人群中移民的潜在补偿性反应。