It's easy to figure out which species is the dominant one at a wildlife rehabilitation center set up in the aftermath of the summer oil spill in southern Michigan.

Just read the small sign tacked to a temporary partition: "Welcome to Snapperville, a friendly suburb of Turtle Town."

Turtles make up close to 90 percent of the 2,300 animals captured and cared for since the late July oil spill that polluted the Kalamazoo River. And true to their history, the hard-shelled reptiles are proving to be resilient.

Rows of black rubber or gray steel bins at the center serve as temporary homes to turtles ranging from 6-ounce spotted turtles to 30-pound snappers.

Turtles ready for cleaning often are covered with mayonnaise to help loosen the coating of oil. They get detail work from a team of volunteers in white coats toiling under hot bright lights.

Toothbrushes and cotton swabs are among the most common tools used to clean black, hardened oil out of every nook and cranny.

About 99 percent of the turtles rescued have survived, a better rate than for birds and other wildlife contaminated by the pollution. Most of the turtles already have been cleaned, rehabilitated and returned to the wild in time for this winter's hibernation.

"It's just the way they're designed," Chris Tabaka, a veterinarian at Binder Park Zoo near Battle Creek, said Wednesday at the rehab center set up by Enbridge Inc. "They've been through some things. They've been through the dinosaur ages. They've lived through thick and thin. They're incredibly tough animals."

The types of turtles affected by the Michigan oil spill can live up to 50 or 100 years, depending on the species. The vast majority should have decades yet to live even after their brush with the spill of at least 820,000 gallons of oil near Marshall.

The rupture came on an Enbridge pipeline running from Griffith, Ind., to Sarnia, Ontario. The pipeline has restarted, but cleanup and wildlife rehabilitation continues.

Roughly 300 turtles might remain in care at the rehab center all winter, depending on how many are discovered or released within the next few days. The stragglers aren't yet strong, active or heavy enough to be released for the winter hibernation.

The turtles likely will be kept warm indoors through the winter so caretakers can better monitor their health.

Canada geese, ducks and muskrats are among the 36 species cared for after the oil spill. But turtles dominate the space inside the rehab center, which once served as a temporary administrative office and employee training center for a nearby casino.

Nearly 300 volunteers have been trained to clean animals, donating a combined 6,400 hours since the late July spill. That supports efforts from Enbridge contractor Focus Wildlife along with the U.S. Fish and Wildlife Service and the Michigan Department of Natural Resources and Environment.

Ann Van Weelden, a volunteer, was cleaning her 129th turtle early Wednesday.

"I just really wanted to help in some way," she said.