Black bear DNA research could yield most accurate new science about Alabama populations
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It's an odd feeling that comes over a person when you're walking alone on a sandy woods road and suddenly realize there are more bear tracks than deer.
It's cool, but in an uneasy kind of way.
That was the case Thursday as I accompanied a group of hunters, who for more than 30 years have been peacefully co-existing with Ursus Americanus floridanus, or the Florida black bear that continues to thrive in a relatively small area of southwest Alabama.
For CR's Hunting Club President Lee Turner and long-time members and brothers Greg Bridges and Russell Bridges, bear sightings are so commonplace they hardly cause a stir among them and the other members of the 1,500-acre club, located in the heart of Bama's bear country off Radcliff Road. "If you want to impress people up here, show them a picture of a hog," said Greg Bridges, who along with his brother has been hunting in bear country since 1977. "Over the years I have come to appreciate bears. They're such a beautiful animal."
Turner said the club on the north side of Radcliff Road has always harbored a population of bears, but it has really seemed to increase over the past five years.All three men and other club members have captured hundreds of trail camera pictures of bears. They also said that it is common during deer season for at least one member to return to camp with a new bear-sighting story to tell.If seven of us were to go sit a stand this afternoon," Greg Bridges said Thursday, "I guarantee at least one of us would see a bear."Added Turner, "There's also a good chance that all of us would see a bear."
The appearance of a population increase on the club's land is likely due to a couple of factors.
Firstly, Turner said club members have started seeing a greater number of bear cubs in their pictures and in person. He said many of the sows appear to be giving birth to at least two cubs and triplets are not uncommon. Secondly, he said clear-cutting of property on two sides of the club over the past five years combined with intensive management of the mixed long-leaf pine, scrub-oak bottom habitat on CR's land have helped to also concentrate the animals.
At several spots along club roads, it was easy to spot where a bear or bears had climbed to the top of an oak tree and broken off the top branches to get at the acorns. Foot prints leading to and from the tree, obvious claw marks gouged into the tree's bark and a scat pile left little doubt that it was a bear that had climbed the tree - most likely more than once.
Interestingly, it may be those scat piles that help guide Alabama's future management of its black bears, according to Alabama WFF biologist and the state's Large Carnivore Program Coordinator Keith Gauldin.
NEW RESEARCH TO MAP DNA COULD LEAD TO MANAGEMENT STRATEGIES
According to the Alabama Black Bear Alliance, historical accounts suggest that bears once occupied most forested areas in the Southeast and reached their peak abundance in the early 1800s. Old black-and-white photos turned yellow with age and showing hunters with their bear kills can still be seen hanging in rural stores and restaurants.Since reaching their peak, the decline in black bear abundance can be attributed to human disturbance, illegal kills, and habitat loss. Combined with the naturally low reproductive rate of black bears, where sows give birth to one to five cubs every other year, these are serious concerns for maintaining a healthy bear population, according to the ABBA.
Black Bear on its "Day Bed"
In Louisiana, Mississippi, and Texas, the Louisiana black bear is federally listed as threatened under the Endangered Species Act. During the listing process, the U.S. Fish and Wildlife Service determined the status of the Florida black bear as "warranted but precluded" due to lack of data.
A male Florida black bear can weigh between 350 and 400 pounds and sows can weigh as much as 250 pounds. They can live 30 or more years in captivity and 20 to 25 years in the wild, Gauldin said.
For years, the official statewide population estimate has been "50 or less." In reality, that number has no scientific basis in fact, relying mainly on an extrapolation of anecdotal reports, collisions with vehicles and signs a bear leaves behind such as tracks and droppings.
To shed the first scientific light on the true state of Alabama's bears, a team of Auburn researchers working in conjunction with local Alabama Wildlife and Freshwater Fisheries Division personnel has been collecting bear scat for the past two years from properties in Baldwin, Mobile and Washington counties.The team relies on specially trained tracking dogs to locate the bear droppings. The scat is then analyzed to first, determine if it is from a bear. Once confirmed, it then undergoes DNA sequencing analysis.
The goal is twofold, according to Assistant Professor of Wildlife Ecology Tim Steury in Auburn's School of Forestry and Wildlife Sciences.DNA analysis will allow the Alabama to get the first accurate population estimate of the number of bears living within its borders.The current statewide bear population number is almost certainly low considering the growing number of Ursus Americanus americanus or American black bears that have been migrating out of north Georgia and into the hills of northeast Alabama, Gauldin said.
Steury said the scat-tracking dogs have also been used to collect samples from that population in DeKalb and Cherokee counties. DNA mapping analysis could also reveal how the southwest's bears are - or aren't -- connected to other populations, including a healthy population living just across the Alabama/Florida state line and thrives along the entire Florida peninsula.
"One of the problems with the Mobile population could be that they're not connected to any other population. That is not a good thing," Steury said.Without a regular influx of new genetics into any animal population, in-breeding and the resulting physiological impacts could prevent the population from growing, Steury said. Over the long-term, even breeding populations can decrease if the genetic pool is too limited, resulting in high new-born mortality rates.
While Gauldin believes southwest Alabama's population is growing, he said genetic problems could stem from generations of inbreeding long ago when the population was smaller.He said it is too early in the DNA-sequencing process to discuss any possible cures if it is determined southwest Alabama's bears are an isolated population. Steury said his team has only analyzed samples already collected to determine if they were from a bear.
Gauldin's hope is that within the next 10 years, the two populations concentrated for now in opposite corners of the state begin to use its extensive river drainages to find each other. That would most likely occur as young males disperse in search of potential mates, Gauldin said. Gauldin also said that he'd like to be able to outfit as many bears as possible with GPS tracking collars. That would allow scientists to watch the animal's real-time movements , how they interact with other bears and in what habitats they prefer to live."We really are in just the beginning phase of finding out about these bears," Gauldin said.
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