Western PA sites are filling in with WNS. At the beginning of this thread, I posted the first WNS map update of this year. The PA Game Commission reported lots of emergences. Now, we have more details:
http://www.pittsburghlive.com/x/pittsburghtrib/news/pittsburgh/s_782368.htmlThe map has already been updated again. Signs point to this winter being no different than last, with WNS continuing to spread and fill in places that were just reported last year. As surveys are underway now, and WNS has usually shown its worst damage in March and April, I expect we will see a steady stream of reports over the next two months.
On the hopeful side, the annual bat survey of Knox Cave in NY, owned by the Northeastern Cave Conservancy, showed a good bat population. The final number hasn't been released (still counting noses in the photos), but the estimate was some 400 bats are there, primarily Little browns. This is up from the low of 179 in 2009, three years after WNS hit.
For those interested in more historical data, in 1986, there were 571 bats. High point was 2001, when 1,945 bats were reported. In 2007, when this cave was one of the Ground Zero WNS sites, 350 carcasses were found (population not surveyed).
In 2008, the cave was surveyed (3/12) and the bat number was 366; On 2/17/09, the number dropped to 179, the low point after WNS.
As a formal banding study, such as was done at NY's Fort Drum, has not been conducted here at Knox, we can only speculate as to the factors in the colony's population growth. However, it's clear we have survivors. Whether the growth is from reproduction, relocation, or some combination of these and other causes, is not known.
However, many nearby caves are also being surveyed, including other WNS Ground Zero sites. If those results are similar, then it's more likely to be the population stabilizing, and perhaps coming back. Still, this is another hopeful sign six years after the initial impact of WNS.