Eric Gese will speak about jaguars on Friday |

Eric Gese will speak about jaguars on Friday

Dr. Eric M. Gese, a federal research wildlife biologist for the National Wildlife Research Center and professor in the Department of Wildland Resources at Utah State University, spent four years researching the jaguar’s hunting methods in Brazil.

The objective was to determine how many heads of livestock owned by ranchers were lost to predation.

On Friday, Feb. 6, Gese will present a program at the Swaner EcoCenter called Phantom on the Night: Jaguars of Brazil, and to discuss his findings.

The event is scheduled in connection with the Swaner’s "Mountain Lion!" exhibit that will be on display through March.

"I was involved in the 17-year study to figure out mountain lion habits in Utah, which led to the Swaner’s decision of bringing the exhibit to Park City," Gese told The Park Record. "When they approached me to give a presentation, they wanted to give a broader context of big cats that live elsewhere in the world and not just in the borders of Utah."

Gese was the perfect person to ask because in 2000, one of his students who was from Brazil, had approached him about working with jaguars in her native country.

"She wanted to get her PhD and asked me what we could do," Gese said. "So we came up with this idea to find out how big of a problem or how small of a problem jaguars are to ranchers."

They discussed the project with the Wildlife Conservation Society [WCS], which had received a large grant from the Ford Motor Company’s Jaguar car division.

Gese received a portion of that grant to figure out how much livestock Brazilian ranchers were losing to large carnivores.

"When the ranchers complained, other people would accuse them of exaggerating the losses, which kind of mirrored the situation in the United States," Gese said. "The problem was no one had any hard data in Brazil on this and the impetus was to gather data."

So, Gese approached a rancher in the Pantanal, which along with the Amazon, is a stronghold for jaguars in South America.

"He ran 5,000 head of cattle on his ranch and invited us to work on his ranch," Gese said. "He invested in the project by building, essentially, a field station that included a dry-lab facility with computer space, kitchen, bathrooms and bedrooms on his ranch."

When the research started, Gese used conventional radio collars.

"We collared four jaguars and four puma, but couldn’t track them very well," he said. "That was frustrating."

About this time, GPS technology was in its infant stages, and there was only one company making GPS collars.

"So, we decided to use them and began deploying these first-generation collars for the research in Brazil," Gese said. "The data we got back was incredible."

In 21 days, Gese and his student would followed the signals to carcasses of feral boars and other jaguar prey.

"We were able to find the kill rates of the jaguars, which no one had every had before," he said. "We found the ranchers were right. They were losing a lot of livestock. What they didn’t know was they were losing more than they realized."

Instead of losing 70 head of cattle a year, Gese found ranchers were losing between 200 to 300 head a year.

"We held a workshop in Brazil and presented our result to the ranchers and members of the government," Gese said. "What came next was surprising."

The ranchers showed they weren’t exaggerating their losses and the government asked what could be done.

"Like it is in the United States, there was a need to discuss the depredation of livestock and big game," Gese said. "There is also a need use the information we found so everyone can make wise decisions.

"Unfortunately, there hasn’t been much development in that area in Brazil," he said. "The problem is, much like it is in the United States, changes in policy drags on."

An added wrench in the works is a trust issue, according to Gese.

"The ranchers didn’t want the government involved because they didn’t trust the government and wanted things to take care of by a non government organization," he said. "So that’s where things are today."

The Swaner EcoCenter, 1258 Center Dr., will present "Phantom of the Night: Jaguars of Brazil" by Dr. Eric M. Gese on Friday, Feb. 6, from 7 p.m. until 8:30 p.m. Admission is $5 for the general public and free for Swaner EcoCenter members. Seating is limited and reservations are recommended. Reservations can be made by visiting . For more information visit

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