There is a pressing need to quantify the risks of renewable energy developments such as offshore wind farms for protected populations. However, assessments are often based on incomplete data, or fail to consider variation in risk between sexes and at different times of year. We tracked northern gannets foraging from the world's largest colony (Bass Rock, Scotland) across five consecutive breeding seasons. We examine how seasonal and sex differences in behaviour affect the collision risk from planned and operational wind farms within their foraging range and assess the likely consequences for long-term population viability. Both sexes made shorter trips during chick-rearing than prior to chick-hatching, spent a greater proportion of time within wind farm sites and had an eight times greater potential collision risk during chick-rearing. Females made longer trips than males at both these times of year, flew higher and spent more time within wind farm sites, leading to three times greater collision risk for females. After accounting for the potential additional mortality from collisions, and assuming that the death of a parent also led to the loss of its offspring, the breeding population was projected to increase by 3.57% (95% CI: 2.16–5.15%) per year, compared with 6.56% (95% CI: 4.59–8.73%) in the absence of turbines, suggesting a negligible effect on population viability. However, additional mortality could result in greater immigration from neighbouring colonies, potentially affecting their viability and highlighting a need for research within a metapopulation framework to assess the impacts of offshore wind developments on vulnerable species across multiple connected sites.

迫切需要量化可再生能源发展的风险，例如受保护人群的海上风电场。但是，评估通常基于不完整的数据，或者没有考虑性别之间以及一年中不同时间的风险差异。我们追踪了五个连续繁殖季节从世界上最大的殖民地（苏格兰巴斯岩石）觅食的北部塘鹅。我们研究了行为的季节性和性别差异如何在其觅食范围内影响计划内和运营中的风电场的碰撞风险，并评估了长期人口生存的可能后果。在雏鸡饲养过程中，两个性别的旅行时间比雏鸡孵化之前短，在风电场内花费的时间比例更大，在雏鸡饲养期间的潜在碰撞风险大八倍。在一年中的这两个时间段中，女性的行程都比男性长，飞行得更高，并且在风电场内停留的时间更长，导致女性碰撞风险的三倍。在考虑了撞车可能造成的额外死亡，并假设父母的死亡也导致其后代的丧失之后，预计繁殖种群每年将增加3.57％（95％CI：2.16-5.15％），相比之下，在没有涡轮机的情况下为6.56％（95％CI：4.59–8.73％），这表明对种群生存力的影响可忽略不计。但是，更多的死亡人数可能导致从邻近殖民地的更多移民，从而可能影响其生存能力，并突出表明有必要在跨种群框架内进行研究，以评估海上风电发展对多个相连地点的脆弱物种的影响。