Native Ocelots Need Human Help to Survive in U.S., Duquesne Researcher Says
Ocelots already are endangered in the U.S. and since the mid-20th century, have started living in the shallow end of the gene pool.
The cats, only around 50 to 100 animals living in two groups in southern Texas, must dodge cars, fight disease, compete with bobcats and coyotes for food, fend off humans and find a disappearing habitat to survive. But even survival tactics as finely honed as their claws have failed to stave off a loss of genetic diversity, said Dr. Jan Janecka, assistant professor of biology at Duquesne University. Janecka co-authored a paper , in collaboration with researchers at the Caesar Kleberg Wildlife Research Institute of Texas A&M-Kingsville, comparing historical and current genetics of ocelots (1853 to 2005) that was published Feb. 26 in PLOS ONE, a scientific journal of the Public Library of Science.
Findings show that these cats need human intervention to assist in their survival-an ironic situation because human behavior has been the greatest factor in the decline of the only tropical cat that still breeds in the U.S.
Before the 1960s, the bobcat-sized ocelots roamed Texas, Arkansas, Louisiana and Arizona. Now the survivors have less range and less genetic diversity.
"The population is so small that the breeding cats, to some extent, wind up related, exposing offspring to the negative variants that are often carried in recessive genes," Janecka explained. "Inbred individuals of many species often have lower fitness and fertility, smaller body size when born and higher susceptibility to disease. Even if we could make a small positive impact on reproductive fitness, we could help to increase their chances of survival."
The most effective resolution, Janecka said, is to relocate some ocelots, as has been successfully done in the case of Florida mountain lions, exchanging members between the two different Texas groups or even with groups in Mexico and Central America.
"It's important to preserve populations on the extreme areas of their range because of the animal's potential special adaptations to different environments, the importance of maintaining future evolutionary lineages, and their ecological role in these ecosystems," he said.