Scientists have discovered that the effects a house has on surrounding bird communities in a rural area can extend as much as 200 meters away. A study led by Dr Michale Glennon and Dr. Heidi Krester of the Wildlife Conservation Society has revealed that in the areas surrounding homes within Adirondack Park, birds sensitive to humans were 26 percent less likely to be found within 200 meters of the home than in surrounding forest. They also found that bird species well-adapted to humans were 36 percent more likely to be found within 200 meters of the home.
The homes included in the study were located on large lots of 5 to 40 acres. The home density was much lower than suburban developments and were nestled within otherwise unaltered habitat. The bird species that were the most sensitive to the presence of humans included the black-throated blue warbler, hairy woodpecker, hermit thrush, black-throated green warbler, scarlet tanager and winter wren. Since these species showed little tolerance for disturbances brought about by human presence (noise, pets, lights, vehicles, habitat destruction), they could be regarded as indicator species of undisturbed forest. One such species considered to be an indicator species is the scarlet tanager—if scarlet tanagers are present in an area of forest, it is most likely undisturbed forest.
Although the study focused on the impact homes had on bird populations, the study authors noted that birds could provide a measure of overall biodiversity and the effects human presence had on the ecosystem as a whole.
Photo © Julie Larsen Maher / WCS. Ovenbirds are a human-sensitive species of bird.