Mike Sredl and Dennis Caldwell
Arizona Game and Fish Department
Nongame Branch
2221 W. Greenway Road
Phoenix, AZ 85023-4399
Reproduced from Sonoran Herpetologist (Tucson Herpetological Newsletter) 13:1
Wintertime Population Surveys - Call for Volunteers
Chytrid fungus has been implicated in declines of amphibian populations in Central America and Australia, but had not been implicated in declines of North American amphibian populations until recently. Epidemics due to chytrid fungus infections were first reported in Arizona in 1998 from Cienega Creek. Retrospective analyses of frog skin indicate that chytrids have been in Arizona since at least 1992. The demographic effects of chytrid epidemics can be dramatic (in two populations studied, over 100 dead lowland leopard frogs, Rana yavapaiensis, were counted), but the geographic and temporal scales at which they operate are not well understood, and may be equally dramatic. For example during the winter of 1999, five die-offs due to chytrid fungus were studied in Arizona.
Last year Arizona Game and Fish and the Tucson Herpetological Society (THS) began to develop a proposal which would have funded a grassroots volunteer effort to address the need to gather more information on the scale of these epidemics. Because of eligibility criteria, this proposal was not submitted. Game and Fish may soon have funds to support disease studies, including the volunteer effort on a statewide scale. Dennis Caldwell has stepped forward to coordinate activities in the THS this winter.
In addition to providing valuable information on the geographic and temporal scales of die-offs, specimens collected during these surveys will support research in Arizona and elsewhere on chytrid fungus epidemiology and other important research. If you are interested in taking part in these surveys, please contact Dennis or I. During fieldwork, remember to follow the DAPTF Fieldwork Code of Practice when you could act as a potential vector for amphibian pathogens.
Mike Sredl and Dennis Caldwell
(602) 789-3515
(520) 624-0198
msredl@gf.state.az.us
DJCaldwell111@aol.com
LOCALITY RECORDS WINTER 1999-2000: ARIZONA
These reports refere only to the recent winter survey in Arizona, and not to previous surveys.
Methods:
temperature data loggers @ 3 sites (Ta & Tw)
daytime searches: 30 visits to 14 sites between 11/7/1999 and 1/16/2000
histological analyses
Results:
dead frogs @ 9 sites
chytrids confirmed @ 7 sites
SPECIES IN ARIZONA, USA, CONFIRMED WITH CHYTRIDIOMYCOSIS
This species list includes frogs from the recent winter survey as well as previous records.
Hylidae
Hyla arenicolor
Ranidae
Rana berlandieri
R. blairi
R. chiricahuensis
R. yavapaiensis
Updated 3 February, 2000
Rick Speare