A recently published study by University of Florida researchers finds the state’s iconic snail kites tend to return to the same general area they were born for nesting and raising chicks and that this behavior could actually be hurting the endangered birds.
The study finds snail kites have a strong affinity for their birthplace when it comes to where they choose to breed. Even birds that pick a new location to nest often pick spots with similar environmental conditions of their birth home.
“And this is something that we as people tend to think humans do quite often,” said University of Florida professor of Wildlife Ecology Robert Fletcher, Ph.D. “I was born in the smoky mountains and when I left home I wanted to live in the mountains somewhere else. There’s been a very long history dating back almost one hundred years, where scientists thought that animals may do this as well and yet there’s been very limited evidence of animals in the wild actually having this behavior and so it was unique in that regard.”
Choosing a habitat the birds are more familiar with could seem like an advantage, but Fletcher said not in the case of the snail kites.
“They were actually more likely to have their nests fail and most of these failures come from predators preying on their nests. So in this case there was a cost to this propensity to want to move to areas like their home.”
About half of the nests researchers monitored failed due to predators like raccoons, snakes and owls. The study is based on 17 years’ worth of data monitoring the birds’ nomadic movements throughout their range in Central and South Florida. The snail kite population dwindled down to about 700 birds in 2008, but since then has been on the rebound, primarily due to nesting success among birds in the Central Florida region. The birds’ population was estimated at about 1,700 in 2014.
The University of Florida study was published in the journal Proceedings of the Royal Society B. “What I hope is that work like this will help us better understand exactly how do snail kites choose where they’re breeding and how can we manage habitats to promote breeding in areas that we’re managing for snail kites,” said Fletcher. “And perhaps deter breeding that wouldn’t be good for snail kites because of growth.”
