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What’s Happening to Bats in the Northeast? An Update on White-nose Syndrome. David Stilwell U.S. Fish and Wildlife Service Many Slides Originally from Alan Hicks New York State Department of Environmental Conservation. What is White-nose syndrome (WNS) ?.
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What’s Happening to Bats in the Northeast?An Update on White-nose Syndrome David Stilwell U.S. Fish and Wildlife Service Many Slides Originally from Alan Hicks New York State Department of Environmental Conservation
What is White-nose syndrome (WNS) ? WNS is a name we have given to an as yet unidentified agent or agents that is apparently causing mass mortalities at a growing number of bat hibernacula in and around NY. The most obvious symptom of the problem is the presence of a white fungus around the nose of some, but clearly not all affected animals. The fungus can also be present on the wing or tail membrane. Bats are also flying near affected sites during daylight hours and are often found dead near the entrances or on nearby structures. Day flying bats are reported more frequently nearer the hibernacula, and as winter progresses beyond late January. Affected animals have substantially depleted fat supplies, which are exhausted long before food is available in the spring. Affected animals tend to shift to roosts in colder regions of the caves or mines, and concentrate in unusually high numbers near the entrances. This is often within the zone of light penetration.
2006 2-16-06 First ObservationHowe Cave WNS photographed. Up to 18 dead bats per trip were observed. Paul Ruben Caves not searched Contaminated Caves 2006
Caves not searched Contaminated Caves 2006 Contaminated Caves 2007 2007 Increasing reports of bats on the winter landscape beginning in late January 1-18-07 First ObservationSchoharie Caverns Many bats unusually close to the entrance
Caves not searched Contaminated Caves 2006 Contaminated Caves 2007 2007 3/28/07 First Report Gages Cavern 805 carcasses eventually collected. No white noses observed 3/14/07 Standard winter survey of Hailes Cave Thousands seen dead. White nose on half of the survivors 4/25/07 Knox Cave 350 carcasses collected WNS observed
3/14/07 Hailes Cave Survey Roughly half the bats observed had a white fungus around the muzzle, It had not been noticed at either Schoharie Cavern, or Gages Cavern, although it was seen on animals at Knox.
3/14/07 Hailes Cave Survey Carcasses, or parts of carcasses, were found on most rocks emerging from the resurgent stream. Examinations to date (not yet complete) indicated that body parts represent at least 600 animals.
3/14/07 Hailes Cave Survey Among the missing were all 685 Indiana bats (Myotis sodalis). Since the discovery of this species at Hailes Cave By Donald Griffin during the 1930’s, this was the first winter survey that we are aware of where they were not observed. M. sodalis have been absent during all three visits since.
2007 Surveys (primarily routine Indiana bat surveys) Not Surveyed No mortalities Large scale mortalities Small scale mortalities Aeolus Cave A few bats were found dead in the entrance room; a rather common occurrence since the 1930’s. Surveys of other sites demonstrated that the problem was limited in distribution. Pink sites had evidence of mortalities. Sharer Cave This event was believed to be flooding related. Merlin's Cave About 50 bats reported dead. This is a recently discovered cave. These mortalities are suspicious. 100 km
Most sites checked to date within 80 miles of the 2007 caves are affected Currently Involves 400,000 to 500,000 Animals
2007-2008 Mortality Event Percent Decline Based on Winter Survey Counts
How Might WNS be Spread? Bat to bat transmission during fall swarm or pre-hibernation movements? Bat to bat transmission in hibernacula? Bat to bat transmission at maternity colonies? Cavers or researchers? Background and Biology Photo by Merlin Tuttle, BCI
Indiana bats, and to a lesser extent little brown bats typically hibernate in dense clusters. It is hard to imagine a condition more conducive to the spread of disease, if WNS is a disease.
What is the Cause of Mortality? • No real answers to date • Bats are starving to death- very underweight, bats leaving hibernacula early • Involved researchers: virologists, mycologists, pathologists, bacteriologists, immunologists, toxicologists
Boston University Disney APHIS USGS Wildlife Health Center UC Davis Participating Researchers/Laboratories Bucknell CDC NYS DEC Pathology USGS Ft Collins Columbia University Colorado State Indiana State University of Colorado Humboldt State Cornell University USFWS NYS Department of Health
Summary • WNS has persisted for at least 2 years at some sites. • It appears to be killing 90+% of bats at these sites. • There may be varied vulnerability among species and sites. • It appears to be rapidly spreading (although we do not know what IT is or if/how it may be spread). • Look for white fungus on noses or exposed membranes. Remember that not all WNS sites have bats with white noses. • Look for bats in unusual roosts, especially near entrances. • Monitor for winter reports of bats (Myotis) flying during the daytime, or roosting on buildings.
Indiana Bat Hibernacula in New York State 9,000 2,000 (10 Sites) 0-50 100 4,000 700 38,000 Confirmed affected Apparently /possibly(?) clean
Indiana Bat Summary • 7 Indiana bat hibernacula in NY and 2 in VT confirmed as affected • ~10% of rangewide population affected to some degree • Short-term effects appear to vary among sites • Additional monitoring is needed
What is the Service doing? • Created a Webpage for information sharing http://www.fws.gov/northeast/white_nose.html • General FAQ document • Caver decontamination protocols • Field equipment decontamination protocols • Future sampling for additional research into cause/spread of WNS- T.B.D. • Mapping caver/biologist movements vs. affected sites • Tracking surveyed sites for presence/absence of WNS • Holding weekly conference calls among Service and States • Coordinating researcher calls when needed • Applying for funding • Assisting with permit needs/review for listed species issues • Assisting with field work
Next Steps??? • Summaries/reports from all involved labs to date- June 2008 • Meet with researchers to discuss other hypotheses, data needs, possible management strategies- June 2008 • Example data collection/research/monitoring options: • Track known maternity colonies • Fall swarming weight studies • 2008-2009 “on” year for Indiana bat hibernacula surveys • Additional surveys of other hibernacula • Captive studies • Contaminants
Funding Opportunities • Internal Service Sources- Regions 3 and 5 applied for 2 pots of money. Region 4 may have applied as well. • Opportunities for States • Traditional S6 • Multistate Conservation Grant Program. ~4 million dollars. 0 Match. Letter of intent due May 2nd • Northeast Regional Needs Conservation Program • Potential future competitive SWG grants