Effects of Non-target Supplemental Feeding on Small Mammal Populations
Abstract
Supplemental bird feeding is a widespread hobby throughout western culture. Although it brings joy to many, the effects it has on wildlife should be researched further as supplemental feeding may result in more harm than good, not only for birds, but also small mammals. Supplemental feeding can lead to higher population densities of small mammals in one area which often results in an abnormally high transmission of pathogenic and parasitic disease. To study the differences in population size of small mammals between the presence of bird feeders and natural settings, six camera traps were placed in a rural residential area in Putnam County, Georgia. Three cameras were placed facing bird feeders and three in natural settings. Species presence was recorded three days a week from 12:00 am Monday to 12:00 am Thursday between November 11, 2019 and January 29, 2020. During the first month of data collection, the times in which pictures were taken were recorded as well. A total of 5,077 mammals were recorded during the 36 days: gray squirrel (4270), eastern chipmunk (458), raccoon (113), Virginia opossum (65), house cat (52), white-tailed deer (36), gray fox (35), field mouse (22), armadillo (11), eastern cottontail (11), and domestic dog (4). A single factor ANOVA test was used to test the difference between population densities at bird feeders and natural sites. Squirrels, chipmunks, raccoons, and house cats were found in significantly higher numbers around bird feeders compared to natural sites. Not only do bird feeders contribute to a higher population density in certain species, but also, they attract more predators such as house cats. More research should be done to investigate the effects of bird feeders on the behavior of small mammals as well as the magnitude in which excess predation at supplemental bird feeders affect a community overall.
Effects of Non-target Supplemental Feeding on Small Mammal Populations
Supplemental bird feeding is a widespread hobby throughout western culture. Although it brings joy to many, the effects it has on wildlife should be researched further as supplemental feeding may result in more harm than good, not only for birds, but also small mammals. Supplemental feeding can lead to higher population densities of small mammals in one area which often results in an abnormally high transmission of pathogenic and parasitic disease. To study the differences in population size of small mammals between the presence of bird feeders and natural settings, six camera traps were placed in a rural residential area in Putnam County, Georgia. Three cameras were placed facing bird feeders and three in natural settings. Species presence was recorded three days a week from 12:00 am Monday to 12:00 am Thursday between November 11, 2019 and January 29, 2020. During the first month of data collection, the times in which pictures were taken were recorded as well. A total of 5,077 mammals were recorded during the 36 days: gray squirrel (4270), eastern chipmunk (458), raccoon (113), Virginia opossum (65), house cat (52), white-tailed deer (36), gray fox (35), field mouse (22), armadillo (11), eastern cottontail (11), and domestic dog (4). A single factor ANOVA test was used to test the difference between population densities at bird feeders and natural sites. Squirrels, chipmunks, raccoons, and house cats were found in significantly higher numbers around bird feeders compared to natural sites. Not only do bird feeders contribute to a higher population density in certain species, but also, they attract more predators such as house cats. More research should be done to investigate the effects of bird feeders on the behavior of small mammals as well as the magnitude in which excess predation at supplemental bird feeders affect a community overall.