Slithering toward restoration

Nurturing the Louisiana pinesnake population

Sarah Farmer

Southern Research Station

November 2, 2023

A brown and tan snake looks at the camera with its round, black eye as it rests on a bed of orange pine needles. — The Louisiana pinesnake is one of the most difficult snakes to spot in the wild. That is because they are exceptionally rare and spend more than 70% of their time underground. (*USDA Forest Service Photo by James Childress*)

The Louisiana pinesnake (Pituophis ruthveni) is one of the rarest snakes in the country.

In 2006, Josh Pierce, a Forest Service wildlife biologist, began building a database of snake sightings. The database draws from historical records, published literature, roadkill reports, incidental captures, and all other records that can be verified. It now has almost 700 unique records of Louisiana pinesnakes.

A woman and three men stand in a pine forest looking at a paper map. Around them, tall, black pines rise above the pine needles and leafy vegetation on the forest floor. — Team members gather to look at a map of the Louisiana pinesnake release site. The team includes, from left, Emlyn Smith, Catahoula Ranger District biologist on the Kisatchie National Forest; Josh Pierce, wildlife biologist with the Southern Research Station, and Gordon Henley, director of the Ellen Trout Zoo in Lufkin, Texas. (*USDA Forest Service photo by Christopher Schalk*)

“We’re at a point with the dataset where we can start answering questions needed by the Kisatchie National Forest, U.S. Fish and Wildlife Service, and other partners,” said Pierce.

For the past 13 years, zoos have been raising Louisiana pinesnakes in captive breeding facilities and releasing them in a restored longleaf pine forest on the Catahoula Ranger District of the Kisatchie National Forest in Louisiana. The snakes are raised by the Memphis Zoo, Audubon Zoo, Ellen Trout Zoo, and the Fort Worth Zoo. The snake's habitat is found in Louisiana and Texas.

“Our goal is to provide partners with information on where this species stands at the current site and how to best allocate the 100 snakes per year that the zoos produce,” said Pierce.

On the tailgate of a truck, a hand holds a tan snake with dark brown spots and stripes on a white cloth bag with black hand-written identification numbers scrawled across it. A scientific device also rests on the table. — A young Louisiana pine snake, born and raised in a captive breeding facility, has reached the release site on the Kisatchie National Forest. The snake is on top of the bag it traveled to the site in. Researchers will measure the snake and outfit it with a passive integrated transponder tag before releasing the snake. (*USDA Forest Service photo by Christopher Schalk*)

About 400 snakes have been released at the site on the Catahoula Ranger District. The researchers estimate that the population, including released and their offspring, is about 100.

“We’re planning simulation models to project whether the population is self-sustaining at 100 individual snakes,” said Forest Service researcher Chris Schalk. “There’s no baseline information – the number of snakes that might have lived there historically is unknown.”

In the 1990s, Forest Service researcher Craig Rudolph, now retired, began monitoring the snakes in ten Texas counties. Monitoring in two counties continues, but no snakes have been seen at either site since 2012.

“The Louisiana pinesnake is really hard to detect and observe in the wild,” said Schalk. “It spends up to 70% of its time underground, so you can imagine trying to monitor it.”

“There’s evidence to suggest that almost all of the wild populations of this snake are declining,” said Pierce, who recently contributed to a study on using camera traps for monitoring Louisiana pinesnakes.

For now, the population on the Catahoula Ranger District seems to be doing well. The snakes are benefitting from a long history of collaborative conservation – for both the Louisiana pinesnake and the longleaf pine.

At the reintroduction site, most of the tall trees are longleaf pine. The ground is covered in grasses and flowers, and the soil is sandy. In short, it is a perfect home for many species including the Louisiana pinesnake and their main food, pocket gophers.

Humans have long had a role in creating healthy longleaf pine ecosystems. Before colonial settlers arrived on the continent, Indigenous peoples stewarded the land with fire. Fire remains a critically important tool – longleaf pines need frequent, low-intensity fire to be healthy.

Today, managers on the Kisatchie National Forest use fire to maintain and restore the longleaf ecosystem.

“This work highlights the multidisciplinary nature of species conservation and the multiple partnerships that make it happen,” said Schalk.

A tan snake with dark brown spots rests on the pine-needle-covered ground. Pine cones and the base of a pine tree trunk are behind it. — A newly released Louisiana pinesnake takes in its new longleaf pine habitat on the Kisatchie National Forest in Louisiana. (*USDA Forest Service photo by Brad Moon*)

Editor’s Note: This feature supports the year-long celebration marking the 50th anniversary of the Endangered Species Act signed into law Dec. 28, 1973. The Louisiana pinesnake is federally listed as threatened, one of nearly 1,600 plant and animal species listed as threatened or endangered in the U.S.

The Southern Research Station originally published this feature.