Sonia Hernandez made national headlines a couple of years ago with her kitty cam project by strapping little cameras on 60 pet cats whose Athens owners let them roam outdoors.
Hernandez and graduate student Kerrie Anne Loyd found that most of the time, the Clarke County kitties just laid around, just like they do at home. But nearly half of them spent some time hunting, and quite a few were successful at it.
The cats’ prey included lots of invertebrates such as cicadas and large grasshoppers, along with animals such as the little green lizards called Carolina anoles, little mammals such as chipmunks, and infrequently, birds.
Now Hernandez and her students are into a second phase of kitty cam research — tracking the activities of a feral cat colony on an unnamed Georgia barrier island, cats who are regularly fed by a humans, who bring food to a place where the cats gather — along with foxes and raccoons, who drop by to feed after the cats are through.
At least in this group, the feral cats are more avid hunters than their domesticated relatives, though their analysis is not yet complete.
Of the 31 cats in the barrier island colony, 59 percent hunt, as opposed to 44 percent of the Athens pet cats. The feral cats’ prey is often little frogs, she said.
The percent that hunt may actually be higher. The researchers know that two of the cats don’t hunt, but nine are undetermined, Hernandez told a crowd in Athens’ Little Kings Shuffle Club Thursday night in the latest installment of the popular “Science Cafe” series.
According to one estimate by scientists at the Smithsonian Conservation Biology Institute and the U.S. Fish and Wildlife Service — hotly
disputed by pro-cat organizations — domestic cats kill as many as 3.7 billion birds annually, along with nearly 21 billion mice, voles, chipmunks and other little mammals.
The kitty cam research is also one small aspect of a bigger picture Hernandez described to about 100 listeners — the study of urban wildlife.
When people grow up in cities, as an increasing proportion of humans do, it’s easy to lose touch with nature. But urban wildlife can be an important bridge, she told the crowd in Little Kings.
“Any opportunity we can create for people to connect with nature in an urban environment is im
portant,” said Hernandez, who holds a joint appointment to the University’s Warnell School of Forestry and Natural Resources and the Southeastern Cooperative Wildlife Disease Study, a unit of the College of Veterinary Medicine.
Some wild creatures area moving to the city, just like the worldwide human shift from the country to the city.
Coyotes have worked their way east and south, and are now common in Georgia, including Athens; armadillos root in our gardens, and deer roam through Athens, as do opossums, raccoons and smaller creatures such as chipmunks. Feral hogs, a widespread pest in farm and forest, are now also turning up in suburban environments in the South, according to researchers at Clemson University. In Miami, feral chickens disturb the early morning calm.
Even the iconic bird of the Everglades, the white ibis, is moving into town in South Florida.
Hernandez and her group are now studying some of those south Florida birds, who turn into beggars when they come into town.
“They sit around and wait for handouts,” she said.
Hernandez and graduate student Catie Welch are interested to know how moving to the city changes life for the birds. Is there a cost to them, for example when they move to a diet that’s more stale bread than wild-caught fish? Is there a health cost, such as increase disease transmission, to the birds’ increasing population densities and closer contact with humans and other animals? Are they more likely to be infected with salmonella, a top cause of diarrheal disease in birds?
And what are the effects when their range is diminished — when they don’t migrate or roam so much anymore?
In the wild, ibises move many miles in a day, she said.
In town, they appear to move less and be under more stress than wild birds; the urban birds have increased stress hormones, and poorer immune function, an indication that poor food, poor water, close contact with humans and other factors may take a toll.
Hernandez will know more about the ibises in a few years. This fall she will begin a new, five-year study that will include larger groups of birds, some in city habitats, and some that live in wild areas. With larger sample sizes and stronger research methods, she hopes to get more definitive data about the two groups’ differences.
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