One of Canada’s most endangered species, the Vancouver Island Marmot, is on the road to population recovery thanks to the Toronto Zoo. The zoo’s captive breeding program and biobank of genetic material have helped restore several populations –not only marmots, but also wood bison and other threatened species in Canada and around the world.
Like other facilities devoted to preserving plant and animal diversity, the Toronto Zoo’s biobank stores a variety of different biospecimens. Overall, more than 50 species are represented, and they’re mostly Canadian animals that are threatened by extinction. The goals of the biobank are to preserve the genetic diversity that occurs naturally in a large population and to contribute to captive breeding and reintroduction projects.
In Canada, encroachment by humans is one of the main factors threatening animals –although the impact may not be as direct as it is in other countries. Even if much of the land in Canada remains untouched, human activity often creates barriers that prevent animals from moving through their habitats. As a result, isolated populations form, stopping the exchange of genetic material. That’s problematic, because a lack of gene exchange can lead to inbreeding and spell trouble for the population down the road.
The Toronto Zoo selectively preserves samples to maximize the genetic variation in their collection. As Dr. Gaby Mastromonaco, curator of Reproductive Programs and Research at the Toronto Zoo, told the Toronto Star, it’s important to preserve many different genes, particularly ones that confer disease resistance, survivability and even fur and coat colors or variations in size.
At this point, the Toronto Zoo’s biobank consists mostly of sperm from endangered animals. That’s no surprise, considering artificial insemination is commonly used in captive breeding projects and requires banked sperm.
Although no eggs are preserved in the biobank, Mastromonaco has banked skin cells from females in the hope that they might be useful for breeding in years to come. As Mastromonaco, who is the only staff reproductive physiologist in Canada and head of one of only a handful of such programs in North America, reminds us, technology is constantly evolving, and a biospecimen that’s not relevant today could prove useful in the future.
The Toronto Zoo’s program has already had many successes. For instance, the Vancouver Island marmot might be extinct if not for the zoo’s captive breeding program using biobanked sperm. The zoo also has several other captive breeding and reintroduction projects underway, which involve breeding rare and endangered species in human-controlled settings and, if possible, releasing these animals back into their natural habitats.