Urbanization and insects: A contrast in trends between latitudinal temperature gradients and the urban heat island effect in cities along the eastern United States
Disciplines
Biodiversity | Entomology
Abstract (300 words maximum)
Urbanization is associated with a range of biological stressors, including increased local temperatures due to the urban heat island effect. In individual cities, increasing temperatures are associated with declines in biodiversity. This contrasts with major trends outside cities, where biodiversity generally increases with temperature along latitudinal and elevational gradients. To understand the interaction between the urban heat island effect and latitudinal trends in biodiversity, we quantified species richness of a common urban insect group (ants) in four cities (Boston, Queens, Baltimore, and Raleigh) that span a latitudinal gradient along the eastern coast of North America. We collected ants using baits placed at the base of a single red maple (Acer rubrum) at 128 locations across cities. At each tree, we continuously measured temperature and humidity using iButton temperature loggers over the course of 11 months in 2013. We predicted that species richness would increase along a latitudinal temperature gradient from the coldest (Boston) to the warmest (Raleigh) cities. We also predicted that within cities, there would be a negative relationship between temperature and species richness. Our results supported both predictions, suggesting that the urban heat island effect disrupts large-scale trends in biodiversity along ecological gradients. These findings are relevant to future research concerning the effects of human development on ecological processes and trends, particularly those involving weather and climate disruptions.
Academic department under which the project should be listed
CSM - Ecology, Evolution, and Organismal Biology
Primary Investigator (PI) Name
Clint Penick
Urbanization and insects: A contrast in trends between latitudinal temperature gradients and the urban heat island effect in cities along the eastern United States
Urbanization is associated with a range of biological stressors, including increased local temperatures due to the urban heat island effect. In individual cities, increasing temperatures are associated with declines in biodiversity. This contrasts with major trends outside cities, where biodiversity generally increases with temperature along latitudinal and elevational gradients. To understand the interaction between the urban heat island effect and latitudinal trends in biodiversity, we quantified species richness of a common urban insect group (ants) in four cities (Boston, Queens, Baltimore, and Raleigh) that span a latitudinal gradient along the eastern coast of North America. We collected ants using baits placed at the base of a single red maple (Acer rubrum) at 128 locations across cities. At each tree, we continuously measured temperature and humidity using iButton temperature loggers over the course of 11 months in 2013. We predicted that species richness would increase along a latitudinal temperature gradient from the coldest (Boston) to the warmest (Raleigh) cities. We also predicted that within cities, there would be a negative relationship between temperature and species richness. Our results supported both predictions, suggesting that the urban heat island effect disrupts large-scale trends in biodiversity along ecological gradients. These findings are relevant to future research concerning the effects of human development on ecological processes and trends, particularly those involving weather and climate disruptions.