Ocelot killed in Hidalgo County suggests species’ range has expanded

An ocelot killed by a car in 2021 is confirmed to be genetically different from the known populations of ocelots in deep South Texas, meaning more of the endangered wild cats exist than previously thought.

By Gaige Davila, Texas Public RadioApril 18, 2024 10:15 am, ,

From Texas Public Radio:

In 2021, a male ocelot was killed after being hit by a car on Highway 281, just south of Linn, Texas. Its location intrigued conservationists and researchers. They asked: What was it doing away from the critically endangered species’ usual habitat range?

Some thought there was a chance the ocelot was an illegal pet living nearby that found its way to the highway. Though ocelots once roamed over a wide swath of Texas, Oklahoma, Arkansas and Florida, the largest concentrations of the cats in the U.S. are in the Rio Grande Valley’s eastward counties.

Male ocelots will travel for their own space, usually within two to 10 miles, after reaching sexual maturity. But this ocelot, found north of Edinburg, in one of the more rural areas of the Rio Grande Valley, was about 50 miles away from the closest known population. However, the thornscrub ecosystem surrounding that area of Hidalgo County has the prey and shelter necessary for the nocturnal species to thrive.

A team that included former Gladys Porter Zoo veterinarian Thomas DeMaar collected the ocelot and x-rayed it, confirming that it had been killed by a car. DeMaar collected muscle tissue from the dead ocelot and sent the samples to Duquesne University’s Jan Janecka, an expert in ocelot genetics who originally mapped the DNA of Texas’ populations.

After two different methods of testing, then repeating both, Janecka confirmed that the ocelot was related to the same breeding populations in deep South Texas. But more surprising was that the cat had more unique genetics than those known groups of cats. It shared the same DNA as ocelots found in the Mexican state of Tamaulipas.

This is the first time that an ocelot has been found outside its known range in the U.S.

This discovery is notable because it means that there may be more than the 100 or so ocelots spread between the Laguna Atascosa National Wildlife Refuge, in Cameron County, and on the Yturria and El Sauz ranches in Willacy County. Texas has the only breeding population of ocelots in the country, but small numbers range in Arizona and New Mexico. There is no accurate count on how many ocelots there are in the U.S.

There is the chance that the ocelot crossed from Mexico into the U.S., as one was documented doing in the 1990s between the Santa Ana National Wildlife Refuge and rural Tamaulipas. But the physical barriers of fencing, water, and human infrastructure make it unlikely. It’s also possible the genetics found in this Hidalgo County ocelot are present in the Cameron and Willacy County ocelots, too, but they have not been detected yet because species’ overall U.S. population is so small.

But the Hidalgo County ocelot could also suggest that an undetected population that relates closer to a Mexican population of ocelots is living in the thornscrub of northern Hidalgo County.

“It makes you wonder how many more ocelots are hidden out there,” DeMaar said.

Jake Strouf / Defenders Of Wildlife

An ocelot mother and kitten crossing Buena Vista Road at the Laguna Atascosa National Wildlife Refuge.

Plans to expand ocelot populations in the Rio Grande Valley and make them more genetically diverse were already underway before the Hidalgo County ocelot discovery.

Ocelots are going to be bred and raised at a planned Ocelot Conservation Facility in Kingsville, Texas Parks and Wildlife (TPWD) announced last month. Those ocelots will be introduced at the East Foundation-owned San Antonio Viejo Ranch, a 150,000 acre parcel of land spread between Starr and Jim Hogg counties.

The East Foundation, which also owns the El Sauz Ranch, signed a “safe harbor” agreement with the U.S. Fish and Wildlife Service last month. The agreement allows any private landowner in Zapata, Jim Hogg, Starr, Brooks and Hidalgo County to opt-in to allowing the East Foundation to monitor ocelots living or traversing through their properties.

The benefit for the landowners, TPWD said, is that they will not have to deal with “Endangered Species Act regulatory surprises related to ocelots that could impact their land uses, and they can maintain their privacy.”

Regardless if landowners opt into the agreement, they will not have land use restrictions if an ocelot is released within 31 miles of their property. The possibility that a population of ocelots in Hidalgo County exists bridges conservation efforts among the Rio Grande Valley counties.

“Hidalgo County becomes like a puzzle piece right there in the middle between Starr and Cameron and Willacy Counties,” said Sharon Wilcox, the senior Texas representative for Defenders of Wildlife and an expert in ocelot conservation. “And so this allows us to think more expansively about an ocelot-occupied area in the region.”

The Hidalgo County ocelot discovery opens multiple possibilities and avenues for ocelot conservation in the U.S. But it also points out one of its biggest inhibitors: Ocelots are killed by cars more than anything else. That fact means the future of the species’ conservation is based on a multifaceted infrastructure change, which includes more wildlife crossings under Texas roadways.

It also means informing communities on how to coexist alongside ocelots as their population grows through the region.

This kind of conservation serves more than just saving an endangered animal. DeMaar said the ocelot serves as an indicator species for deep South Texas because it needs a healthy habitat to survive. Their presence shows that the Rio Grande Valley’s environment, despite a swath of development and drought, is still suitable for all life, not just wildlife.

“If this ocelot is still here, that means this environment still has a chance,” DeMaar said. “And if this [ocelot] is the first shiny thing that is lost in this gem of an ecosystem, it means that the habitat is declining in its quality, and it will continue declining until it cannot support life. And that life really talks about us, too.”

TPWD said it will take a few years before ocelots are born from the Ocelot Conservation Facility.

If you found the reporting above valuable, please consider making a donation to support it here. Your gift helps pay for everything you find on texasstandard.org and TPR.org. Thanks for donating today.