Population Trends of Central European Montane Birds Provide Evidence for Adverse Impacts of Climate Change on High-Altitude Species

Abstract

Climate change is among the most important global threats to biodiversity and mountain areas are supposed to be under especially high pressure. Although recent modelling studies suggest considerable future range contractions of montane species accompanied with increased extinction risk, data allowing to test actual population consequences of the observed climate changes and identifying traits associated to their adverse impacts are very scarce. To fill this knowledge gap, we estimated long-term population trends of montane birds from 1984 to 2011 in a central European mountain range, the Giant Mountains (Krkonoše), where significant warming occurred over this period. We then related the population trends to several species' traits related to the climate change effects. We found that the species breeding in various habitats at higher altitudes had more negative trends than species breeding at lower altitudes. We also found that the species moved upwards as a response to warming climate, and these altitudinal range shifts were associated with more positive population trends at lower altitudes than at higher altitudes. Moreover, long-distance migrants declined more than residents or species migrating for shorter distances. Taken together, these results indicate that the climate change, besides other possible environmental changes, already influences populations of montane birds with particularly adverse impacts on high-altitude species such as water pipit (Anthus spinoletta). It is evident that the alpine species, predicted to undergo serious climatically induced range contractions due to warming climate in the future, already started moving along this trajectory.

Clinging on to alpine life: Investigating factors driving the uphill range contraction and population decline of a mountain breeding bird

“…Chen, Hill, Shiu, et al, 2011). For birds too, uphill range shifts (Freeman & Freeman, 2014; Tingley, Monahan, Beissinger, & Moritz, 2009), declines in range size (Scridel et al, 2017) and population size (Flousek, Telenský, Hanzelka, & Reif, 2015; Lehikoinen et al, 2019) and even local extirpation of mountain specialists (Freeman et al, 2018) have been attributed to climate change, although the small number of relevant studies and their sometimes inconsistent findings renders drawing general conclusions regarding the response of alpine birds to climate change difficult. However, while there has been some improvement in understanding macroecological changes in high‐elevation biodiversity due to climate change, detailed long‐term empirical studies that address ecological mechanisms affecting species across broad spatial scales remain scarce (Scridel et al, 2018).…”

Declining population trends of European mountain birds

“…From a conservation point of view, it is, however, equally important to understand the effects of climate change on population densities that do not necessarily coincide with distributional changes (Chamberlain & Fuller, ). In general, while populations of lowland bird and butterfly species have been shown to change according to climate change scenarios in Europe and North America (Breed, Stichter, & Crone, ; Devictor et al, ; Lindström, Green, Paulson, Smith, & Devictor, ; Stephens et al, ), the population status of species in the mountain areas is generally poorly known (Chamberlain et al, ; Scridel et al, ; but see Flousek, Telenský, Hanzelka, & Reif, ; Lehikoinen, Green, Husby, Kålås, & Lindström, ).…”

Long-term phenology of two North American secondary cavity-nesters in response to changing climate conditions

“…One method used to examine the effects of climate change on life-history traits is to monitor productivity by measuring clutch size, which has implications for population dynamics (Crick 2004). Studies conducted over elevation gradients report smaller clutch sizes and delayed breeding at higher elevations (Dillon and Conway 2015;Flousek et al 2015;Boyle et al 2016). Climate patterns, such as reduced precipitation in the months before the breeding season, can also cause deviations from optimal clutch sizes (Davies and Cooke 1983).…”