Later this summer, 23 yearling Blanding’s turtles will scramble toward ponds at protected sites in a suburban forest preserve. Despite the numbers painted on their shells, this is not a turtle race. Animal health experts at Shedd and ecologists at the Forest Preserve District of DuPage County hope that it is the beginning of long, productive lives for these members of a state-endangered species. In a way, they are in a race: for their survival. And they’ve been given a head start.
Focus on locals
About two years ago, Dr. Matt O’Connor, staff veterinarian, saw an opportunity for Shedd to get involved in the Forest Preserve District of DuPage County’s head-start program to restore local populations of Blanding’s turtles (Emydoidea blandingii).
“With our experience caring for 26 species of turtles on site, we were well-positioned to join the collaborative recovery effort for this endangered species,” he said. The veterinarian, who has been involved in turtle rescues in the Philippines and Madagascar, added, “I’m passionate about taking care of the unique wildlife that’s endangered in our own back yard.”
Dr. Matt, 37, is a lifelong turtle lover who grew up in DuPage County. But, he noted, “In all my time tromping around the forest preserves as a teenager, I never came across any Blanding’s.”
That’s because, by that time, local populations of the semiaquatic native turtles—easy to identify by their “smiling” upturned upper jaw, canary yellow chin and throat, and attractive yellow speckling on the dark olive face and shell—had been drastically reduced by collection for the pet trade, loss of their wetland habitats and mortalities on increasingly busy roads.
But tipping the scales toward the species’ local extinction were exploding suburban populations of raccoons and other predators that feasted on eggs and hatchlings. Even now, 90 percent of nests are destroyed each year. Surveys showed Blanding’s populations were skewed toward older adults, indicating few young turtles were surviving. Dr. Matt said, “Twenty years down the road, without replacement of the older turtles, it would be the death sentence for the species.”
In 1996, ecologists with the Forest Preserve District of DuPage County launched a head-start program. That spring, they gathered gravid, or egg-carrying, females, and waited for them to lay. Then the moms were outfitted with radio transmitters, so they could be located in subsequent years, and released. The ecologists incubated the eggs and nurtured the hatchlings for a year, then released them in safe habitats. As of last year, the district had hatched nearly 3,300 Blanding’s turtles. For the 2019 breeding season, 178 hatchlings were distributed among five head-starting partners, which, in addition to Shedd, include Brookfield Zoo, Peggy Notebaert Nature Museum, the Wheaton Park District’s Cosley Zoo and the Forest Preserve District of Will County.
“The amount of resources and expertise required to recover a species from the brink of local extinction can be daunting,” Dr. Matt said. “Having all these partners involved helps us identify diets, or lights, or care that results in the healthiest turtles or best growth rates. In a group setting, we can answer difficult questions more effectively, and we stand a better chance of saving the species.”
The partners’ responsibility is to provide husbandry and veterinary care. “Every institution has to have some sort of relationship with a vet to deal with any issues that come up,” Dr. Matt said. Shedd is well-prepared with an on-site animal hospital. Under the auspices of the Animal Response Team, the veterinarian dedicated a small room in the A. Watson Armour III Center for Aquatic Animal Health and Welfare as a head-start room. Then he purchased everything a turtle nursery needs, from large, low rubber tubs and filtration to UV lights and artificial plants, and amended Shedd’s endangered and threatened species permit from the Illinois Department of Natural Resources to include the endangered hatchlings.
On Sept. 5, 2018, Dan Thompson, a forest preserve district ecologist, delivered two dozen newly hatched turtles, numbered 97 through 120 with a nontoxic, water-based paint pen. They are the offspring of two mothers—Blanding’s turtles only lay about a dozen eggs each nesting season. The tiny turtles were divided evenly between two 55-gallon tubs that, in the beginning, contained no more than 2 inches of water because the hatchlings are not strong swimmers. Low rocks and sprigs of small-leafed plastic plants provided basking and hiding places, and a metal-halide lamp radiated ultraviolet “sunshine,” critical for the turtles’ bone and shell growth, about a foot above each tub’s island.
“In the wild,” Dr. Matt explained, “the turtles would hatch in the fall, eat a few times, then dig into the mud of the pond bottom to hibernate. Most babies overwinter with the remnant of the yolk sac for nutrition.” These turtles, however, had the advantage of eating six days a week throughout the winter.
Menu for growing turtles
In the beginning, the hatchlings were placed in two trays, each divided into 12 compartments (shown above), so they could be fed individually. Once aquarists were satisfied the little ones were eating well on their own, food was doled out in the habitat tubs, with plenty to go around so that each turtle could eat at its own pace
The turtles were fed a high-protein diet of frozen bite-sized planktonic prey, cultured at Shedd, and commercial hatchling food: Sundays, bloodworms; Mondays, brine shrimp; Tuesdays, mysis shrimp; Wednesdays, pellets; Thursdays, bloodworms, Fridays, pellets. Saturdays, however, were fast days. “That’s to prevent them from growing too rapidly,” Dr. Matt explained. “In the wild, they’re not always going to find food every day.”
They didn’t always eat what was put in front of them, either. Adult Blanding’s turtles are omnivorous, but the hatchlings are pure carnivores. “They’re hard-wired to eat stinky, smelly live-looking stuff, which is high in protein,” the veterinarian said. “But the thawed frozen items aren’t totally balanced, so we wanted them to also get the pellets, because that’s a balanced diet.” At first, the hatchlings weren’t having any. Eventually, a few cautiously snapped at the pellets bobbing in the water. Others observed and tried them. Soon, all the little turtles had learned to eat the pellet food.
By March, the 23 surviving hatchlings were big enough—about 2 inches in shell length—to graduate from frozen live foods to living live foods. “Their main diet now is gut-loaded crickets”—those fed a commercial formula of essential nutrients—“and earthworm chunks,” Dr. Matt said. They also get crayfish and silversides—moving prey that they had to learn to hunt. The aquarium’s live foods program provides a clean, consistent and steady source of small prey for animals throughout the aquarium.
The turtles do have favorite foods. “The first time they had crickets, they filled up so much that they didn’t want to eat the next day,” Dr. Matt said.
Even though the baby turtles are adorable, their caregivers have kept contact to a minimum. “We’re training these turtles to survive in the wild,” Dr. Matt emphasized. Husbandry care is administered once a day in a matter of minutes. “In the morning, they’re accounted for, we check that each one looks bright, alert and healthy, we throw the food in and we walk away. We don’t want to be associated with food.” The turtles are checked again briefly in the afternoon before the attending aquarist leaves for the day.
“When we clean them, we make a little disturbance so that they jump in the water and swim away instead of stare at us. We want them to view humans as a threat so that they don’t get illegally collected,” Dr. Matt said. Researchers have found that turtles imprinted on humans are less wary, making them more prone to predation too.
The short in-person visits don’t mean the turtles aren’t checked on throughout the day. “We can monitor them remotely,” the veterinarian continued, “We have a web cam to see what they’re doing. We can even read the numbers on their shells to see who is out and about.” Aquarists can observe them from their computers at their desks or on their smart phones.
The turtles also have monthly health checks, when they’re quickly measured and weighed, and their fading numbers are refreshed. But that’s the extent of their interactions with people.
As the turtles have grown, they’ve been regrouped by size—larger and smaller—between the two nursery tubs. And their water depth has been increased. They’re strong swimmers now and energetically explore their domains for food. While the ecologists with DuPage County Forest Preserve District do not set a specific length or weight requirement for release, the now-palm-sized turtles appear well-prepared to fend for themselves in the wild.
“Before they’re released, we’ll give the turtles a final physical examination to make sure they’re healthy.” Dr. Matt said. “We’ll take final weights and measurements, microchip them for identification and then transport them to undisclosed locations to be released.”
Then the head-start team will prepare for a new batch of hatchlings.
The survival of Blanding’s turtles in Illinois depends on head-starting large numbers of hatchlings, a technique that has worked in the recovery of other endangered turtle species.
“The best sign of success is when the head-started turtles show up as breeding adults,” said Dr. Matt. “And in the last five to 10 years, we’ve seen head-started females producing eggs. That’s when you start to know you’re making a difference.”
—Karen Furnweger, web editor
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