(e) = estimate, *morbidity, not mortality, (s) = suspect; diagnosis is not finalized, but field signs and historic patterns indicate the disease.

California Fish and Game (CFG), Cornell University (COR), Idaho Wildlife Health Laboratory (ID), Michigan Department of Natural Resources (MI), No diagnostics Pursued (NON), USGS National Wildlife Health Center (NW), Other (OT), Tufts University (TU), University of Illinois (UIL), Unknown (UNK).

Written and compiled by: Anne Ballmann / LeAnn White - Eastern US, Krysten Schuler - Western US, Jennifer Bradsby – Biological Technician

To report mortality or receive information about this report, please contact the USGS National Wildlife Health Center, 6006 Schroeder Road, Madison, WI 53711

Quarterly Mortality Reports

Ranavirus confirmed in amphibians from several states (MA, TN, WY)

Several states had confirmed amphibian cases of ranavirus in the spring of 2009. The affected species included wood frogs, tiger salamanders, and marbled salamanders. The submitters from all 3 locations reported observations of amphibians with characteristic skin ulcerations or lesions. The infected tiger salamanders were collected from a reservoir in WY. The infected wood frog tadpoles were from a MA vernal pond that had previously experienced a ranavirus-associated mortality event in 2000 and 2001 resulting in a loss of >95% of the wood frog tadpoles and spotted salamander during those years. The ranavirus-infected marbled salamanders collected this spring were from a TN pond where ranavirus-infected amphibians also were recorded in 1999 and 2000 and amphibians with chytrid fungal infections were documented in 2001.

Chytrid fungal infections in Leopard frogs (NY)

Chytridiomycosis, an epidermal infection caused by the pathogenic chytrid fungus, Batrachochytrium dendrobatidis, was detected in a wild population of southern leopard frogs from NY. The affected site was thoroughly surveyed this spring and researchers are confident that all the affected frogs were collected at that time. Clinical signs of chytridiomycosis include loss of righting reflex, lethargy, abnormal postures (e.g., frogs spreading legs away from body), and discolored or sloughing skin. Since chytrid fungus is most likely spread by direct contact between individuals or contact with infected water, frogs should not be moved from one area to another and should only be handled when necessary with clean equipment (gloves, sample bags, etc).

Large mortality of Brandt’s cormorants around San Francisco (CA)

Beginning in mid-April 2009, natural resource agencies, including National Oceanic and Atmospheric Administration (NOAA), California Department of Fish and Game (DFG), and U.S. Fish and Wildlife Service (USFWS) began receiving reports of dead and dying cormorants and other coastal birds in the Bay area. Dead Brandt’s cormorants were found at a nesting colony on Alcatraz Island, and more were recovered on the coast from San Francisco Bay south to Monterey. In addition, dozens of sick cormorants were recovered by several local wildlife rehabilitation centers. Sick birds were found to be extremely emaciated. Brandt’s cormorants and Western grebes were the primary species affected. Necropsy results from Brant’s Cormorants sent to the USGS National Wildlife Center showed severe emaciation. Tests for domoic acid, a natural marine algae toxin fatal to birds, were negative, as were tests for Newcastle disease, avian influenza and West Nile virus. Researchers speculate that a strong upwelling may have displaced a large amount of water and prey offshore. Since cormorants are near-shore feeders their prey base, including anchovies and juvenile sardines, may have been placed beyond their feeding range. Common murres, another near-shore feeder, were observed to have declined nesting success. Other seabirds that feed further off-shore did not appear to be affected. The die-off ended by late June and a final mortality estimate is being generated, but thousands of birds were thought to be affected. Local USFWS biologists have noted that this pattern is similar to those observed during past El Niño events.

Bat mortality at summer roosts (CT, IN, NJ, CO, WA, TX, OR, UT)

The USGS - National Wildlife Health Center (NWHC) is investigating cases of higher than normal bat mortality at roost sites from multiple states this summer. Other states: MA, NH, and WI, have received similar reports from the public and may reflect an increased awareness and population monitoring due to publicity of bat white-nose syndrome (WNS) winter mortality. In several cases, both adults and young pups are affected. Species involved primarily are Big brown and Little brown bats in the eastern and central U.S., while Townsend’s big-eared, Brazilian free-tailed, Rafinesque’s big-eared, and Western long-eared bats from western states have been submitted for examination. As observed in summer 2008, some bats are roosting on outside walls during daylight hours and increased numbers of individuals are observed beneath maternity roosts. Anecdotal reports from several areas in the eastern US indicate a reduction in colony size compared to previous summers. Emaciation is a frequent finding although trauma, predation, and rabies have been identified as cause of death in several cases. During summer surveys in areas confirmed to have WNS, collected bats with evidence of moderate wing damage are being closely examined for the presence of Geomyces destructans, the fungus causing skin damage seen with this devastating disease. Thus far, however, there has been no evidence to support a link between these summer mortalities and WNS. Bog turtle mortality investigation in the eastern US (MA, NY, NJ) Increased mortality of bog turtles has been observed in several Northeastern populations undergoing long-term tracking studies this past spring. Field observations of some live turtles found evidence of skin discoloration at various locations on the body including the head, neck, and digits. In some cases, claws appear to be oozing or have sloughed. The National Wildlife Health Center is assisting with the disease investigation of possible causes for this morbidity and mortality. A lack of fresh, intact specimens to compare among sites experiencing mortality has been challenging. Diagnostic tests are underway and no consistent finding has been identified.

The Quarterly Mortality Report represents the most current information available to the USGS National Wildlife Health Center at the time of publication. We encourage researchers to contact us to acquire data directly. External request forms for mortality information can be obtained from Jennifer Bradsby at 608-270-2443 or email: jbradsby@usgs.gov.