Predicting the combined impacts of future management and climate change on moorland bird species

Understanding the combined effects of wildlife management and climate change on species is important for planning appropriate interventions. However, predictions of the effectiveness of management interventions alongside climate change impacts remain rare. We investigated the importance of combined management‐climate change predictions for upland moorland bird populations in Great Britain (GB). Current management over many moorland areas comprises rotational burning of heather and predator control, which benefit some species but negatively impacts others. We used land cover data, heather moor burning data and bird survey data across 8095 2‐km grid cells to model how upland bird populations may respond to land management and climate change scenarios. More spatial variation in abundance of each species was explained by underlying environmental predictors, including key climate and land cover variables, than by moorland management intensity. We predicted red grouse (Lagopus lagopus), the primary target of current management, to decline by 33% [30%–38%] across GB if management promoting their numbers (for hunting) ceased, even if land continued to be dominated by suitable habitat. Under the same scenario, we predicted smaller declines in populations of curlew (Numenius arquata; 11% [7%–14%]) and golden plover (Pluvialis apricaria; 6% [3%–9%]), two species of high conservation value considered beneficiaries of current management. When a cessation of grouse moor management was considered in conjunction with future climate change, predicted declines were much stronger. This difference was particularly noticeable for golden plover (30%–37% declines by the 2040s; 27%–34% by the 2080s), though stronger declines were also predicted in red grouse (2040s, 52%–62%; 2080s, 49%–80%) and curlew (2040s, 25%–32%; 2080s, 15%–26%). Such differences in population trajectories were particularly pronounced at a regional scale, with stronger population declines predicted in the combined scenario in most regions. Synthesis and applications. Our study illustrates the value of combining predictions of the impacts of management and climate change on animal populations. Management decisions guided by models fitted only under contemporary scenarios may lead to unexpected, and potentially undesirable, population trajectories as climatic conditions change over the short and medium term.