New project aims to boost antelope herds
If you thought you haven't been seeing many antelope around Elgin and the San Rafael Valley these days, you're right. A 2011 survey of the area found only 16 animals living in the Elgin area and nine in the San Rafael Valley herd - a 50-percent decline over three years ago, according to estimates from Arizona Game and Fish Wildlife Management Supervisor Brad Fulk.
There was only one buck present with each herd during the 2011 survey. And what's more, observers identified only one fawn between the two herds. Therein lies the problem, says Fulk, who is managing the Pronghorn Antelope Fawn Enhancement Project set to take place in the Elgin area over the next three years.
Because there are no fawns living to adulthood to replace an aging population of mature antelopes, the decline in the herd has accelerated in recent years.
The Fawn Enhancement Project has three goals as it tries to reverse this trend, Fulk said. First, he plans to augment the current population by introducing new antelope into the two herds. Second, he wants to determine the "overall environmental factors that are causing these problems." And third, he hopes to improve fawn survival rates - which he says have been close to zero for the past four years - through methods that include trapping and hunting coyotes.
"The bottom line is sustainability of a native pronghorn antelope population," he said.
Efforts to augment the herd are set to begin Jan. 26 in the Prescott Valley, home to a large antelope population surrounded by "extensive development," according to Fulk."Every two years we use it as a transplant source," he said.
Game and Fish plans to trap up to 70 animals, herding them into corrals. The antelope, which Fulk hopes will be 25 percent males and 75 percent females, will be examined by veterinarians, inoculated with antibiotics and ear-tagged before being loaded into stock trailers for the 350-mile ride to Elgin.
Fulk says he is also planning on fitting 15 of the animals with radio collars in an effort to track the movement of the antelope over the next two years. Data gathered from the collared antelope will also be used to try to identify the factors that are impacting the antelope herds here.
According to Glen Dickens, who is involved with the project as a board member and project manager of the Arizona Antelope Foundation, the monitoring collars cost $35,500, and renting satellite time to upload data will cost an additional $15,000 over the next two years. This is being funded by a combination of sources including the state's game tag fund and foundation grants.An additional $48,000 is being sought, Dickens said, to fund field monitoring by a biologist over the next two years.Dickens estimates the final price tag of the project at $135,000, though organizers note that no general fund tax dollars will to be used for any phase of the project.
Genes and fences
It takes a success rate of 28 percent just to maintain a herd at a constant level, Dickens said. As part of its efforts to grow the local herds, the Fawn Enhancement Project is seeking a fawn success rate in the 40-to-50 percent range.
Several factors have been identified as possible causes of the failure of the recent fawn crops, including a "genetic bottleneck," in which a lack of sufficient numbers of unrelated animals may have resulted in weaker fawns. The introduction of the Prescott antelopes could help address that problem.
Another factor may be the drought conditions of the past several years. Drier winters have led to a reduction in feed for the antelope when the does are pregnant. Antelopes prefer to eat forbs (herbaceous flowering plants like milkweed and sunflowers) and woody plants rather than grass or shrubs. Without adequate winter forage, the experts say, it could be that the does are not getting the nutrition they need to produce healthy fawns.
Development in the area has also created some difficulties for the antelope. Namely, their ability to roam has been curtailed by the fencing of property.Antelope, unlike deer, do not jump vertically to clear fences. They need at least 16 inches between the bottom of a fence and the ground to be able to squeeze under and move from one feeding ground to another. As a result, antelope-friendly fencing is an ongoing effort in the Elgin area, Fulk said, adding: "But there's more to be done," he said.
He praised the local ranchers for these efforts and for their work at providing watering spots for wildlife.
One fence, the U.S.-Mexico border barrier running through the San Rafael Valley, is credited with providing some measure of protection for the antelope. "(The barrier is) considered a net benefit stopping uncontrolled mortality in Sonora," according to the project proposal.
That's because poaching remains a problem in Sonora, Fulk said. "Once they [the antelope] crossed the border, the chances that they would come back were pretty slim."
Coyote control
Game and Fish experts consider predation of the antelope to be a major factor in the failure of the fawn crop, and the Fawn Enhancement Project proposal focuses on the coyote as the main predator of the antelope fawns. The original proposal called for aerial gunning, trapping and hunting of coyotes as a method of boosting fawn survival.
However, Game and Fish has now abandoned the idea of aerial gunning, which carried a price tag of $12,300 annually for a total cost of $36,900 over the three years of the project. In addition, many people, including participating ranchers, were nervous about the public perception of an aerial shoot, Dickens said.
That leaves trapping and hunting.
Trapping will be contracted for a total cost of $36,000 over three years, and will take place from March through early May. And because trapping is not allowed on public land, all trapping will be done on private ranch land with the cooperation of ranch owners.
Hunting, which the project proposal describes as "the least successful method" of coyote control, will be done "by department personnel and volunteers, sportsmen's groups and other volunteers from the general public."Hunting will take place on both private and public lands, with the first hunt set for March.
"Night-time predator calling in" will also be allowed in pronghorn areas. That's the practice of using a hand-held or battery-operated call, similar to a duck call, to simulate the sound of a prey animal in distress and draw the attention of a coyote. As a rule, the technique is not allowed at night, but an exception is being made for this coyote hunt.
Fulk explained that the coyote hunt will be "concentrated to areas and times just prior to the fawn drop and will only include traditional methods of hunting and trapping."
However, because coyotes are very resilient animal, "Within four months of a coyote removal effort, the habitat is re-occupied at the same or higher densities," Fulk explained. "The whole goal is to grow fawns by removing coyotes for a two-month period," he said.Fulk said he has no idea how many coyotes there are in the area, and has no idea how many coyotes will be killed during the project.
There will be no coyote removal in the Las Cienegas area in Sonoita. Instead, the Las Cienegas antelope herd will serve as a control group that will be used to compare fawn survival rates between this group and the two herds in Elgin and in the San Rafael Valley where the coyotes will be hunted and trapped.
According to Dickens, there are approximately 80 animals in the Las Cienegas herd. Still, the herd has a fawn survival rate of only 4 percent, well below the ideal rate of 28 percent, so there is cause for concern for this herd, as well.
Reaction
While the possibility of aerial gunning raised concerns, a traditional coyote hunt appears to be more palatable to locals, including Ron Pulliam, a member of the board of the national wildlife conservation group Defenders of Wildlife."Personally, I have no special qualms if it is going to enhance the survival of a threatened species," he said."There is a need to do something to enhance the herd," Pulliam added. "The numbers are really very low and that is a very special population."
Zay Hartigan, who lives in the San Rafael Valley, agreed, though with some reservation.
"I hope the pronghorn can hang on. I like the pronghorns," he said. "I'm not opposed to thinning the coyotes, but there's always a question when people start managing wildlife."
Coyote predation may or may not be the culprit in the demise of the antelope herds in the Elgin area. Further research may be able to provide some answers, say the experts behind the Fawn Enhancement Project
Because there are no fawns living to adulthood to replace an aging population of mature antelopes, the decline in the herd has accelerated in recent years.
The Fawn Enhancement Project has three goals as it tries to reverse this trend, Fulk said. First, he plans to augment the current population by introducing new antelope into the two herds. Second, he wants to determine the "overall environmental factors that are causing these problems." And third, he hopes to improve fawn survival rates - which he says have been close to zero for the past four years - through methods that include trapping and hunting coyotes.
"The bottom line is sustainability of a native pronghorn antelope population," he said.
Efforts to augment the herd are set to begin Jan. 26 in the Prescott Valley, home to a large antelope population surrounded by "extensive development," according to Fulk."Every two years we use it as a transplant source," he said.
Game and Fish plans to trap up to 70 animals, herding them into corrals. The antelope, which Fulk hopes will be 25 percent males and 75 percent females, will be examined by veterinarians, inoculated with antibiotics and ear-tagged before being loaded into stock trailers for the 350-mile ride to Elgin.
Fulk says he is also planning on fitting 15 of the animals with radio collars in an effort to track the movement of the antelope over the next two years. Data gathered from the collared antelope will also be used to try to identify the factors that are impacting the antelope herds here.
According to Glen Dickens, who is involved with the project as a board member and project manager of the Arizona Antelope Foundation, the monitoring collars cost $35,500, and renting satellite time to upload data will cost an additional $15,000 over the next two years. This is being funded by a combination of sources including the state's game tag fund and foundation grants.An additional $48,000 is being sought, Dickens said, to fund field monitoring by a biologist over the next two years.Dickens estimates the final price tag of the project at $135,000, though organizers note that no general fund tax dollars will to be used for any phase of the project.
Genes and fences
It takes a success rate of 28 percent just to maintain a herd at a constant level, Dickens said. As part of its efforts to grow the local herds, the Fawn Enhancement Project is seeking a fawn success rate in the 40-to-50 percent range.
Several factors have been identified as possible causes of the failure of the recent fawn crops, including a "genetic bottleneck," in which a lack of sufficient numbers of unrelated animals may have resulted in weaker fawns. The introduction of the Prescott antelopes could help address that problem.
Another factor may be the drought conditions of the past several years. Drier winters have led to a reduction in feed for the antelope when the does are pregnant. Antelopes prefer to eat forbs (herbaceous flowering plants like milkweed and sunflowers) and woody plants rather than grass or shrubs. Without adequate winter forage, the experts say, it could be that the does are not getting the nutrition they need to produce healthy fawns.
Development in the area has also created some difficulties for the antelope. Namely, their ability to roam has been curtailed by the fencing of property.Antelope, unlike deer, do not jump vertically to clear fences. They need at least 16 inches between the bottom of a fence and the ground to be able to squeeze under and move from one feeding ground to another. As a result, antelope-friendly fencing is an ongoing effort in the Elgin area, Fulk said, adding: "But there's more to be done," he said.
He praised the local ranchers for these efforts and for their work at providing watering spots for wildlife.
One fence, the U.S.-Mexico border barrier running through the San Rafael Valley, is credited with providing some measure of protection for the antelope. "(The barrier is) considered a net benefit stopping uncontrolled mortality in Sonora," according to the project proposal.
That's because poaching remains a problem in Sonora, Fulk said. "Once they [the antelope] crossed the border, the chances that they would come back were pretty slim."
Coyote control
Game and Fish experts consider predation of the antelope to be a major factor in the failure of the fawn crop, and the Fawn Enhancement Project proposal focuses on the coyote as the main predator of the antelope fawns. The original proposal called for aerial gunning, trapping and hunting of coyotes as a method of boosting fawn survival.
However, Game and Fish has now abandoned the idea of aerial gunning, which carried a price tag of $12,300 annually for a total cost of $36,900 over the three years of the project. In addition, many people, including participating ranchers, were nervous about the public perception of an aerial shoot, Dickens said.
That leaves trapping and hunting.
Trapping will be contracted for a total cost of $36,000 over three years, and will take place from March through early May. And because trapping is not allowed on public land, all trapping will be done on private ranch land with the cooperation of ranch owners.
Hunting, which the project proposal describes as "the least successful method" of coyote control, will be done "by department personnel and volunteers, sportsmen's groups and other volunteers from the general public."Hunting will take place on both private and public lands, with the first hunt set for March.
"Night-time predator calling in" will also be allowed in pronghorn areas. That's the practice of using a hand-held or battery-operated call, similar to a duck call, to simulate the sound of a prey animal in distress and draw the attention of a coyote. As a rule, the technique is not allowed at night, but an exception is being made for this coyote hunt.
Fulk explained that the coyote hunt will be "concentrated to areas and times just prior to the fawn drop and will only include traditional methods of hunting and trapping."
However, because coyotes are very resilient animal, "Within four months of a coyote removal effort, the habitat is re-occupied at the same or higher densities," Fulk explained. "The whole goal is to grow fawns by removing coyotes for a two-month period," he said.Fulk said he has no idea how many coyotes there are in the area, and has no idea how many coyotes will be killed during the project.
There will be no coyote removal in the Las Cienegas area in Sonoita. Instead, the Las Cienegas antelope herd will serve as a control group that will be used to compare fawn survival rates between this group and the two herds in Elgin and in the San Rafael Valley where the coyotes will be hunted and trapped.
According to Dickens, there are approximately 80 animals in the Las Cienegas herd. Still, the herd has a fawn survival rate of only 4 percent, well below the ideal rate of 28 percent, so there is cause for concern for this herd, as well.
Reaction
While the possibility of aerial gunning raised concerns, a traditional coyote hunt appears to be more palatable to locals, including Ron Pulliam, a member of the board of the national wildlife conservation group Defenders of Wildlife."Personally, I have no special qualms if it is going to enhance the survival of a threatened species," he said."There is a need to do something to enhance the herd," Pulliam added. "The numbers are really very low and that is a very special population."
Zay Hartigan, who lives in the San Rafael Valley, agreed, though with some reservation.
"I hope the pronghorn can hang on. I like the pronghorns," he said. "I'm not opposed to thinning the coyotes, but there's always a question when people start managing wildlife."
Coyote predation may or may not be the culprit in the demise of the antelope herds in the Elgin area. Further research may be able to provide some answers, say the experts behind the Fawn Enhancement Project
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