||Large-scale spatial variability in urban tolerance of birds
||Callaghan, C.T.; Palacio, F.X.; Benedetti, Y.; Morelli, F.; Bowler, D.E.
||Journal of Animal Ecology
||T5 Future Landscapes
|Data and Software links
||avian; interspecific variability; intraspecific variability; urban ecology
- Quantifying intraspecific and interspecific trait
variability is critical to our understanding of biogeography, ecology
and conservation. But quantifying such variability and understanding the
importance of intraspecific and interspecific variability remain
challenging. This is especially true of large geographic scales as this
is where the differences between intraspecific and interspecific
variability are likely to be greatest.
- Our goal is to address this research gap using
broad-scale citizen science data to quantify intraspecific variability
and compare it with interspecific variability, using the example of bird
responses to urbanization across the continental United States.
- Using more than 100 million observations, we
quantified urban tolerance for 338 species within randomly sampled
spatial regions and then calculated the standard deviation of each
species' urban tolerance.
- We found that species' spatial variability in urban
tolerance (i.e. standard deviation) was largely explained by the
variability of urban cover throughout a species' range (R2 = 0.70).
Variability in urban tolerance was greater in species that were more
tolerant of urban cover (i.e. the average urban tolerance throughout
their range), suggesting that generalist life histories are better
suited to adapt to novel anthropogenic environments. Overall, species
differences explained most of the variability in urban tolerance across
- Together, our results indicate that (1) intraspecific
variability is largely predicted by local environmental variability in
urban cover at a large spatial scale and (2) interspecific variability
is greater than intraspecific variability, supporting the common use of
mean values (i.e. collapsing observations across a species' range) when
assessing species–environment relationships. Further studies, across
different taxa, traits and species–environment relationships are needed
to test the role of intraspecific variability, but nevertheless, we
recommend that when possible, ecologists should avoid using discrete
categories to classify species in how they respond to the environment.
|Persistent UFZ Identifier
|Callaghan, C.T., Palacio, F.X., Benedetti, Y., Morelli, F., Bowler, D.E. (2023):
Large-scale spatial variability in urban tolerance of birds
J. Anim. Ecol. 92 (2), 403 - 416