A long-term study of size variation in Northern Goshawk Accipiter gentilis across Scandinavia, with a focus on Norway

Changing climate and growing human impacts are resulting in globally rising temperatures and the widespread loss of habitats. How species will adapt to these changes is not well understood. The Northern Goshawk (Accipiter gentilis) can be found across the Holarctic but is coming under more intense pressure in many places. Studies of recent populations in Finland and Denmark have shown a marked decline in body size of Northern Goshawks over the past century. Here we investigate long-term changes to Norwegian populations of Northern Goshawk by including material from the Middle Ages. We measured 240 skeletons of modern Northern Goshawks from Norway, Sweden, Denmark and Finland, and 89 Medieval Goshawk bones. Our results show that Norwegian and Swedish female Goshawks have decreased in size over the past century, whilst males showed little decline. Medieval female Goshawks were larger than contemporary females. A decline in forest habitats and a concomitant shift towards smaller prey likel..., Modern comparative material
To analyse changes in both modern and past populations of A. gentilis, metric data of the nominate Accipiter gentilis gentilis were collected from across the Nordic countries (Norway, Sweden, Denmark and Finland). The Northern Goshawk is a sedentary species, generally choosing to breed and winter in the same area. There are some exceptions to this in North America, Fennoscandia and Russia (Squires et al., 2020). However, individuals from Fennoscandia rarely migrate further than 300 Km (Squires et al., 2020). The nominate A. g. gentilis is distributed across Europe and east to the Urals, Caucasus, and Asia Minor, and southwards to NW Africa (Squires et al., 2020). The slightly larger subspecies Accipiter gentilis buteoides breeds in northern Fennoscandia and Siberia, wintering in south and central Eurasia (Ferguson-Lees & Christie, 2005). Goshawks found in northern Finland and northern Sweden likely represent the subspecies A. g. buteoides (Gladkov, 1941; ..., , # A long-term study of size variation in Northern Goshawk Accipiter gentilis across Scandinavia, with a focus on Norway

Changing climate and growing human impacts are resulting in globally rising temperatures and the widespread loss of habitats. How species will adapt to these changes is not well understood. The Northern Goshawk (*Accipiter gentilis*) can be found across the Holarctic but is coming under more intense pressure in many places. Studies of recent populations in Finland and Denmark have shown a marked decline in body size of Northern Goshawks over the past century. Here we investigate long-term changes to Norwegian populations of Northern Goshawk by including material from the Middle Ages. We measured 240 skeletons of modern Northern Goshawks from Norway, Sweden, Denmark and Finland, and 89 Medieval Goshawk bones. Our results show that Norwegian and Swedish female Goshawks have decreased in size over the past century, whilst males showed little decline. Medieval female Go...