Riddle of the skinks

CFB SHILO — Manitoba’s only lizard, the endangered prairie skink, has found a safe place to call home — the training range at CFB Shilo.

And while the grassland at the base provides ample camouflage for the lizards, they can’t escape being the slippery subjects of crucial research into their natural habitat.

Around Onah railway station in the north area of the range lives the most robust population of the tiny and elusive skinks, with more than 200 lizards burrowing near the tracks. Throughout the base are smaller clusters of 30 to 70 skinks, a rarity in other parts of the province.

The unique nature of the base has localized the skinks to an area far removed from its next nearest cousins in North Dakota. The question plaguing researchers is what exactly makes the area skink appropriate.

“The prairie has never been tilled here, it’s the same as if we never came,” said base biologist Sherry Punak-Murphy. “But we don’t really know their natural habitat.”

And this is a concern as encroaching Aspen from Spruce Woods threatens to harm the prairie grassland skinks call home.

University of Manitoba masters student Shane Pratt hopes his ground-breaking tracking project will uncover their habitat mystery.

Having worked with komodo dragons in Indonesia and crocodiles in Australia, the Ontario herpetologist wanted to do something innovative with reptiles on home soil.

Supervised by longtime skink researcher Pamela Rutherford from Brandon University, Pratt checks the Onah Station area for skinks who’ve crawled under artificial coverings set up years before.

Carpet, tile, wood, metal and plywood are all comforting for the small critters and Pratt said they tend to like hardwood the most.

“We’re not completely sure of the effects (of the coverings),” Pratt said, adding he’s unsure if skinks are attracted to the covers or if the shady places attract the shy lizards. “They just hide really well.”

Prairie skinks have been monitored in the area by concerned naturalists for years, but Errol Bredin is the one who worked to have the lizards recognized as a threatened species by Ottawa.

After years of informal study, Bredin left a legacy of skink observations for future generations to follow.

Students from Brandon University and the University of Manitoba now spend hot summer days out in the training range monitoring the behaviour of the fragile lizards.

On a hot, dry morning, Pratt and fellow U of M research student Thierry Lavoie head out into the tall grass at Onah Station to find skinks large enough for radio transmitters.

“This tracking stuff has never been done before,” Pratt said. “We also have no record of them moving more than 10 metres.”

Pratt is concerned he missed his best skink opportunity — as finding the quick lizards is easiest during their spring mating season.

“Their mating habits are a little rough,” the researcher said, showing the scars on one female’s neck from the male biting. While a few more female skinks are spotted under the coverings, along with snakes and beetles, the two researchers hold out for a large male skink to carry a transmitter the size of an adult pinky fingernail.

Skinks upwards of eight grams can be fitted with the tiny transmitter that weighs less than three per cent of its body weight.

Under the second last cover, Pratt finds a male with a special marking.

“Oh, he’s footless,” said Pratt, who after checking his records, realizes this little guy is a new find.

“It’s rare to find male skinks over eight grams,” he said while weighing the new subject. “He’s a cute one though.”

Through a Ziploc bag, the skink’s contorted body is gently measured. The footless skink is a well-suited candidate and leaves the encounter with an additional metal appendage.

Pratt and Lavoie then try something they’ve yet to accomplish — successfully finding an already tagged skink.

Searching the field with a large antenna and working with incoming signals, Pratt follows a male skink to an area and Lavoie grabs hold of the lizard. After making judgments on its path, the researchers are pleased with the results.

“He’s not undercover, which is exactly what I want,” Pratt said. “He’s also moved more than 10 metres. That’s huge right now.”

The skinks will be tracked for the rest of summer, with 20 subjects in total. Measurements have been taken at the base to ensure the most comfortable living arrangements for the skinks, including the maintenence of empty dugouts from German pop-up targets, as they provide superb cover for the lizards.

» dponticelli@brandonsun.com

Republished from the Brandon Sun print edition June 30, 2012