Vancouver, B.C. – After an outstandingly cold, snowy winter resulting in a slow start to the breeding season, the Vancouver Aquarium Marine Science Centre will be releasing recently-hatched tadpoles of the most endangered amphibian in Canada – the Oregon spotted frog – into the wild on Friday, May 5. For years, the Oregon spotted frog population has been in rapid decline in British Columbia and along the Western coast of the United States. As a participant in a global effort called Amphibian Ark (AArk) and a member of the Oregon Spotted Frog Recovery Team, the Vancouver Aquarium has successfully bred this species for eight consecutive years, releasing almost 20,000 tadpoles into suitable habitats in B.C’s Fraser Valley in this collaborative conservation initiative.
On Friday, the Vancouver Aquarium will contribute more than 1,000 tadpoles to the wild population. While the prolonged winter conditions resulted in delayed egg mass production as well as tadpole growth both in the wild and at Vancouver Aquarium, the milder spring conditions have had an accelerating effect and tadpole development and release is on target. Changes in the environment and temperatures can create a disruption in normal hormone production and affect how the adult frogs respond to breeding; this results in varying numbers of egg masses and tadpoles produced each year.
“After eight successful years of breeding these endangered frogs, we are nearing 20,000 tadpoles that have been released into the wild, playing a vital role in rebuilding a population that is in dire need. Without this collaborative conservation program in place, the Oregon spotted frog would be facing an uncertain future in B.C.,” says Darren Smy, senior aquarium biologist at the Vancouver Aquarium Marine Science Centre. “While the road to the recovery of the Oregon spotted frog will be long one, every year we learn more about the species and the challenges it faces in the wild. Over time, we’re also able to learn more about the reproductive needs of Oregon spotted frogs which helps us continually refine our practices and maximize the impact of our conservation efforts.”
This year, for the first time, University of British Columbia PhD candidate Andrew Loudon was able to collect a complete sample set for a study on the symbiosis of Oregon spotted frogs and bacteria. Taking water samples as well as swabs of the frogs, their eggs, and environmental elements such as leaves, Loudon intends to better understand the relationship between the frogs and the bacteria present. By comparing the bacteria of frogs living in the wild and in controlled environments, Loudon hopes to assess the impact on disease resistance.
“Working with the Vancouver Aquarium’s propagation program is instrumental to this research,” said Loudon. “It will help understand the importance of bacteria native to the Oregon spotted frog species and the susceptibility of wild populations to different diseases.”
In recent years, the Oregon Spotted Frog Recovery Team found juvenile frogs as well as egg masses thought to have come from propagated frogs near a release site – both indications that tadpoles and adult frogs released in previous years are healthy and growing. The Recovery Team has also discovered four additional established wild populations – two in 2015 and two in 2017 – bringing the total to seven. These discoveries are signs of the program’s success in supplementing and conserving the wild population.
Early last century, there were hundreds of thousands of Oregon spotted frogs, ranging from northern California up into B.C.’s Fraser Valley. Historically, B.C. populations were found from South Surrey to Hope but due to habitat destruction, the introduction of non-native species such as Eastern Canada’s bullfrog and the reed canary grass, increased pollution as well as disease, their numbers have declined as much as 90 per cent. Oregon spotted frogs spend most of their lives in the water and require connected wetlands and floodplains for habitat.
In an effort to protect this endangered species, the Aquarium joined B.C.’s Oregon Spotted Frog Recovery Team in 2000. A diverse group of biologists and land managers in B.C. are coordinating efforts to conserve, manage, and recover the Oregon spotted frog in Canada. Since 2007, Aquarium staff has been collecting Oregon spotted frog eggs to establish an aquarium-based assurance population. In 2010, the Aquarium became the first in the world to breed this species in human care.
The Oregon Spotted Frog Recovery Program includes habitat management, monitoring, research, and restoration that is conducted in partnership with the B.C. Ministry of Environment; B.C. Ministry of Forests, Lands, and Natural Resource Operations; Canadian Wildlife Service; Department of National Defense; Seabird Island Band; Stó:lo Tribal Council; District of Kent; Fraser Valley Regional District; Greater Vancouver Zoo; Toronto Zoo; Vancouver Aquarium; Mountain View Conservation Centre; Grouse Mountain Refuge for Endangered Wildlife; Wildlife Preservation Trust Canada; Simon Fraser University; University of British Columbia; B.C. Conservation Foundation; and Fraser Valley Watersheds Coalition.
The Vancouver Aquarium is also part of a worldwide effort, along with other zoos and aquariums, to conserve other amphibian species under the Amphibian Ark (AArk) project.
The Vancouver Aquarium Marine Science Centre is a non-profit society dedicated to the conservation of aquatic life. www.vanaqua.org
Editors: Photos and b-roll footage are available upon request.