Michelle Heywood | Friday, March 31, 2017
Inside of the Biodiversity Building you will find keepers working behind the scenes on two of the Oakland Zoo’s conservation projects—helping
both native and nonnative wildlife.
Mountain Yellow-Legged Frogs
Our native Mountain Yellow-Legged Frogs live in two of the three labs. Each year, keepers and supervisors work with San Francisco Zoo, the Department
of Fish and Wildlife, California Department of Fish and Wildlife, and the National Park Service to collect tadpoles from the wild and bring them
back to the Oakland Zoo to be treated for the deadly chytrid fungus (Batrachochytrium dendrobatidis). Chytrid is a type of fungus that lives in
water or moist environments and is causing mass amphibian population declines and extinctions worldwide. The Mountain Yellow-Legged Frogs are able
to carry the chytrid fungus as tadpoles but it is not fatal to their system until they go through metamorphoses. In the late summer/fall of each
year we work with biologists to collect third year tadpoles (yes—this species is in its tadpole stage for three years!) from their native
lakes in the Sierra Nevada mountain range. We then take them back to the Oakland Zoo and treat them with anti-fungal medications until they have
been cleared of the deadly chytrid fungus. The remainder of the year is spent helping the froglets to grow large enough to thrive in their natural
Spring has arrived and keepers in the Biodiversity Building are getting ready to re-infect the now developed and growing frogs with the chytrid fungus.
That is right—after all of this we re-infect the frogs with the fungus! But, why? Re-infecting and retreating the frogs for chytrid is an
inoculation process. We are now “vaccinating” our healthy frogs to help strengthen their immune systems. We are not able to remove chytrid from
their native habitat but we hope to give them the immune support they need to thrive and produce future populations!
In the late spring/early summer we will pack up our larger, stronger frogs for release into the lakes from which they were collected and begin preparing
our labs for the next round of tadpoles.
To learn more about this species and support Oakland Zoo’s onsite conservation projects, check out our Conservation Speaker Series event at 6:30 pm
on Sunday April 9, 2017 in the Marion Zimmer Auditorium.