NRCS works alongside ranchers in fever tick fight

There’s a battle being fought in South Texas. On one side is the cattle fever tick. On the frontline of the offensive fight are local, state and national agencies, associations and landowners working to eradicate the costly pest.

The Natural Resources Conservation Service (NRCS) is one agency working in partnership with these individuals and groups in a statewide fever tick initiative.

“Our involvement in the fever tick initiative or eradication is just one piece of the integrated approach to eradication or control,” said Don Gohmert, Texas’ state conservationist for the Natural Resources Conservation Service.

Gohmert spoke recently at a fever tick summit held at Texas A&M University in College Station. Industry experts, officials and agencies gathered to discuss ongoing efforts to control and eradicate the fever tick.

He explained that NRCS’ involvement is non-regulatory. Its partnership efforts focus on helping landowners with technical assistance, conservation planning and financial assistance programs in the fever tick zone areas of South Texas.
“While we’re not about trying to remove ticks on cattle or deer, we’re trying to create a habitat out there that can be managed better and with less stress and at the same time might control the tick population in some of these pastures that have been quarantined,” Gohmert said.

Fever Ticks

The cattle fever tick was eradicated from the United States in 1943. Despite decades of efforts by federal agencies to control its reintroduction into Texas, the tick is once again thriving in some South Texas counties.

The Texas-Mexico border can be as porous as the waters of the Rio Grande River that separates the two countries. Fever ticks have been found riding the hides of cattle, wildlife and horses that have crossed into Texas.

Two ticks are being fought – Boophilus annulatus and Boophilus microplus. Both are capable of carrying the protozoa that can transmit the disease Babesia or tick fever, which kills cattle.

“Imported Mexican cattle are one of the biggest challenges,” said Dr. Bob Hillman, executive director of the Texas Animal Health Commission. “Up to 50 percent of Mexican origin cattle are carriers of Babesia. … break the cycle by eliminating the tick, that’s the whole purpose of this.”

Hillman noted that while the ticks are present in South Texas, the active Babesia disease has not been identified in any Texas cattle since its eradication.

The commission is the state’s animal health regulatory agency in charge of implementing eradication and control methods. Other agencies involved in efforts include the Agricultural Research Service, Animal and Plant Health Inspection Service and AgriLife Extension.

Surveillance and control measures continue in the 17 South Texas counties that encompass the fever tick zone. More than one million acres and 661 premises are under quarantine due to fever tick infestations or exposure. These counties carry regulatory designations ranging from permanently quarantined to low risk.

Control and eradication measures and options include “scratching” cattle for ticks, scheduled dipping programs of infested cattle in vats of an acaracide, or vacating an infested premise.

Fever ticks are a “one-host” tick. The preferred hosts are cattle. The tick’s entire life cycle will take place on this one animal. Tick larvae are about the size of a pin head and have six legs. As cattle graze, the larvae positioned on blades of grass, reach up and grab the animal’s hair coat. It then finds a spot on the hide to feed.

“That period of time from when the larvae get on this animal, transition to a nymph and transition to an adult and the female is about ready to fall off is about 20 to 21 days,” said Pete Teel, professor of entomology at Texas A&M. “The female falls off of the animal and searches for a place on the ground to lay its eggs. It’s going to look for a suitable microclimate that it thinks is going to be suitable for the incubation of the eggs.”

Cattle in a dipping program are run through a dipping vat every two weeks for six months. Teel said dipping every fourteen days is key to killing adult ticks before the females have a chance to drop off the host and lay eggs.

The fact that these ticks have been found on wildlife such as whitetail deer, red deer and nilgai in the zone complicates eradication, control and movement efforts. The density of exotic wildlife in the area has in turn increased the survivability of larvae.

Larvae that previously would have perished due to the lack of a host are being picked up by wildlife as they move through an infested area.
“The biggest most complex challenge is wildlife,” Hillman said.

Microclimate or microhabitats play another key role in a tick’s survivability.

“Population dynamics of cattle fever ticks are driven by weather and by the diversity and density of hosts,” Teel said. “They are wet, dry season driven.”

Bare ground is the most inhospitable environment for a tick to survive. Rangelands with grass are better, however canopies provide the best environment, Teel said, adding that populations rebuild during wet seasons.

Economic impact assumptions

David Anderson, an ag economist with Texas AgriLife Extension, presented data on an economic model that calculated the cost to eradicate the fever tick if it was found outside of the tick zone in three different regions of Texas.

“This is all based on assumptions. We’ve had to make a lot of assumptions,” Anderson said.

Some of the assumptions included:

Facing Challenges

Fighting the fever tick is costly. It would cost more than $14 million annually to fully fund the tick program in Texas. This figure includes having available all the necessary personnel, equipment and acaracide to fight the battle, according to the Texas Animal Health Commission.

For ranchers, the costly fight adds more red ink to the bottom line of a business that already is struggling with high input costs. NRCS is working alongside these affected landowners to provide technical assistance, along with conservation planning and financial assistance through the agency’s Environmental Quality Incentives Program (EQIP).

“Our mission is primarily to help people help the land. In other words, help the ranchers down there that are living with this situation. There is a burden upon them to gather and present cattle for scratching and dipping, while still trying to make a living in the quarantine zone. Those are the people we’re trying to help through our programs,” Gohmert said.
It all begins with a conservation plan. NRCS field personnel sit down with a rancher to help identify and meet management goals and objectives. Ranchers also can be provided with a map of their operation which delineates features such as fencing, roads, stock tanks and land features.

“This conservation plan is a systematic way for them to look at their resources out there, how they want to operate, how they want to manage,” said Gohmert.
Conservation plans can include cross fencing, prescribed or rotational grazing, brush management, prescribed burning, wildlife upland habitat management and water developments, such as troughs, pipelines and water wells.

“What we want to do is provide this broad scale effort – the chemical, the mechanical, the biological controls that have to be in place to address the tick itself. And, of course, the on-the-land management that goes along with it has got to be part of it,” Gohmert said.

Beyond conservation plans are financial assistance programs, such as EQIP, which has funding available to the 17 fever tick zone counties. The program can pay upwards of 60 percent of the input costs for management practices such as building cross-fencing or digging out stock tanks.

Gohmert added that another $2.5 million to $3 million is budgeted through fiscal year 2010 for the 17-county area.

Resource Conservation and Development (RC&D) is another assistance program available through NRCS. There are four of these program offices operating in the zone.
This community-based program has local people writing and developing grants to assist with information and funding on items such as upgrading dipping vats, expanding dry fire hydrants and helping acquire surface fire fighting equipment.

They work closely with the Texas Animal Health Commission on helping determine where dipping vats should be located, if new vats are needed and who will manage these dipping vats.

“It is a partnership effort among all of us. We’re all in this together. Texas would not be the same state if we would happen to lose the livestock industry,” Gohmert said.

Dipping vats full of an acaracide and water mixture are used to kill fever ticks on cattle. Dipping vats can be an effective eradication and control method for fever ticks because the animal is completely submerged in the mixture.	South Texas cattle are inspected for ticks. Surveillance and control measures continue in the 17 South Texas counties that encompass the fever tick zone.
Fever ticks on a cow’s hindquarters. Photo courtesy of Texas Animal Health Commission.