Feeding Birds in Winter May Do More Harm Than Good
Believe it or not, but over 55 million Americans feed wild birds and spend over $3 billion a year on bird food, and millions more on bird feeders, baths, and other accessories. Many of us have at least one bird feeder in our yards, not only to decorate our outdoor space, but also to attract wildlife. Besides those clever, pesky squirrels that compete for the seed, birds use bird feeders as a fast-food outlet in times of food shortages. While birds do not actually need the food we offer in these feeders, it seems that these backyard feeders are always the popular spot to be, especially during the winter.
However, according to researchers at the University of Exeter and the British Trust for Ornithology, feeding wild bird populations during the winter can actually result in less successful breeding during the following spring.
Wild bird populations are generally thought to benefit from being given additional food in winter but researchers say the effects of such food provision is incomplete.
Researchers studied woodland blue tits that were provided with fat balls as a supplementary food during the winter months. Consequently, this population went on to produce chicks that were smaller, of lower body weight and which had lower survival than the chicks of birds that did not receive any additional food.
Dr Jon Blount from Biosciences at the University of Exeter who led the research said: "Our research questions the benefits of feeding wild birds over winter. Although the precise reasons why fed populations subsequently have reduced reproductive success are unclear, it would be valuable to assess whether birds would benefit from being fed all year round rather than only in winter. More research is needed to determine exactly what level of additional food provisioning, and at what times of year, would truly benefit wild bird populations."
Dr Kate Plummer, lead author of the paper, said: "There could be a number of different explanations for our results. One possibility is that winter feeding may help birds in relatively poor condition to survive and breed. Because these individuals are only capable of raising a small number of chicks, they will reduce our estimation of breeding success within the population. But more research is needed to understand whether winter feeding is contributing to an overall change in the size of bird populations."
The research is published in Scientific Reports.
Read more at the University of Exeter.
Blue tit image via Shutterstock.