1/15/2011 – Hibernating bat census in Carroll Passage

Permit #:  1101-3
Trip Leader name:  Bill Gee

Trip date:  15 January 2011
Project manager:  Bill Gee
Trip purpose:  Hibernating bat census in Carroll Passage
Areas of Cave visited:  CarrollPassage
Trip participants:  Bill Gee, Chandra Ruff, Andrew Mason, Jeff Page, Terry Defraties
Entry Time:  10:15am
Exit Time:  7:30pm
The trip report:  When we did the annual bat census trip back in October, there was some discussion about whether the numbers counted on that trip represented the actual usage of the cave by hibernating bats.  A decision was made to run another bat census trip in January specifically to look for clusters of hibernating bats.  The goal was to make a fast trip to the Mountain Room looking for bats, and possibly send two people out to the water passage since the surveyors report that is where most of the hibernating bats are.

Due to snowy roads and cold weather, the team and plan for the trip was changing as late as Friday evening.  Eventually we wound up with five people.  I had originally planned for two trips, Saturday and Sunday, with the Sunday trip intended to service the stream level data loggers.  We decided to combine the two trips so we could get back to Kansas City before icy weather rolled in late on Sunday.

I arrived at the schoolhouse about 5:45pm on Friday.  Very early Saturday morning Chandra and Andrew pulled in.  I did not hear them arrive.  Jeff and Terry drove in Saturday morning.  We all met at the schoolhouse about 8:30 and drove up the hill shortly after nine.  When we got up to the silo we found two trucks already there.  The survey team was running a camp weekend and had the hole all rigged for us.

The first person down the shaft was me at about 10:15.  While everyone else came down, I got out my laptop computer and reprogrammed the two data loggers at the ladder.  They are now programmed to take a reading every 30 minutes instead of every 15, and they are recording their battery voltage.  Those two loggers are the oldest and should be needing new batteries in a year or so.  Now that they are recording their battery status, I do not need a laptop in the cave to check them.  By taking a reading only every 30 minutes I can let them go as long as a year between downloads.  That takes some pressure off to get regular trips to download them, and it will make graphing the data somewhat easier.

It did not take long to reprogram the data loggers.  I was done about the time everyone was down the shaft and ready to go.  The next item on the plan was to attach a new anchor to the stilling well in Carroll River.  The old anchor was just a big rock.  It proved too fragile, splitting into several pieces sometime during last summer.  The result was the data logger spent most of the summer and early fall out of the water.

We hauled a concrete block about 12 inches square by 4 inches thick.  I had already drilled it, so all we had to do was bolt the stilling well to it and drop it into place.  I carried the block about half way and Andrew carried it the rest of the way.  When we got there, I realized I had forgot to bring a hammer so we could pound the wedge anchors into place.  We used some rocks which came apart after only two or three blows.  The wedge anchors are not in as far as I would like, but they are tight enough to hold the stilling well in place.

The Water Barrier was as cold and wet as it always is.  We paused a few minutes around guano pile 3 so I could put out a new guano gauge.  The previous gauge was washed away a couple of years ago.  While there we saw two cave fish and 3 or 4 adult grotto salamanders in the stream.

At guano pile 14 we stopped for half an hour to take pictures of a bunch of brown mounds.  These were first noticed on the October 2010 trip, but we did not get any photos of them.  The mounds are now confirmed to be dead bats.  They are in an advanced state of decay, basically down to bones and fur.  I photographed about 20 of them close-up.  We did not take any samples. We did not notice any of these carcasses on the 2009 and earlier trips.

There was a solitary bat hibernating right above the carcasses.  I took a picture of it and the photo does not show any signs of White Nose fungus.  Another solitary bat appeared to have a white spot on one ear.  We saw solitary bats throughout the cave but did not make any effort to count them.

From there we went a couple of hundred feet to the Lunch Room where the survey crew was getting ready to start their day.  We chatted for a bit about plans, then went on down the Carroll Passage.  We decided to take Carroll Passage since there is a section around the 4500 to 4000 foot markers where bat clusters have been seen on previous October trips.  Also, not all of our packs were up to the crawling that is required in the Turnpike.

We stopped for lunch about 500 feet downstream from the Lunch Room at about 12:00.  From there we took an hour and a half to get to the Mountain Room, arriving about 2:00pm.  The survey crew was already there, having passed us in the Turnpike.  We did not see any clusters of bats anywhere in the Carroll Passage.  Even the cluster seen in October around the 500 foot marker was gone.

In the Mountain Room we got out a big bolt cutter that Terry brought along.  It was carried in two pieces.  Andrew and I assembled it, then placed it in a spot high above the water and marked with green flagging tape.  The bolt cutter is intended to permit emergency exit through the natural entrance, should that be required.  The head is well greased and wrapped in multiple layers of plastic bags and pallet wrap.

While Andrew and I did that, Terry and Jeff put on wetsuits for a quick look at the water passage.  They returned much sooner than I expected, only about 15 minutes after leaving.

Terry and Jeff went somewhat prepared for cold water, but when they got past the Neck Breaker the air temperature was severely colder than the water temp.  They knew they needed to spend no more than a couple of minutes or risk rapid drop in body temp.  They did not see thousands of bats, rather they saw dozens of small clusters of Indiana bats.  Certainly a sizable population, but they are reluctant to give any more of an estimate.

Just before Jeff and Terry made this trip, Ben Miller guessed the last time he’d observed the same scene was 2003, eight years ago.  With that much time lapse and different parties observing, it’s pointless to speculate on whether the numbers have risen, fallen or remained stable.  But it was worth making the trip to determine that Indiana bats are still using the cave and are still ostensibly healthy at this point.  Since they had no way and no time to get up close to the bats, they weren’t able to look them over for presence of fungus.  We should make this trip again next year (preferably Terry and Jeff again for consistency) and try to determine if the population shrinks over the next season.  We may also consider contacting BCI for suggestions on monitoring or even assistance

We all packed up and left the Mountain Room by 3:00 pm for the trip back.  It took us 3 full hours to get back to the ladder, arriving just a few minutes before 6:00 pm.

Chandra and Jeff elected to go on out of the cave.  Terry, Andrew and I had one more task.  We took a flying trip up to UL2 so I could download data from the fourth data logger.  I led and set a blistering pace.  We made the trip up there in just about 30 minutes, and the trip back in about the same time.  We were back at the ladder shortly after 7:00 pm.  Andrew geared up first and climbed solo.  Terry and I were a bit slower, climbing tandem.  Everyone was out of the cave by 7:30 pm.  We were changed and heading down the hill by 8:00 pm.

I spent the night in my camper at the schoolhouse while Jeff and Terry got a motel room in Camdenton.  The next morning the three of us met at the schoolhouse to sort through the stack of lumber.  Jeff and Terry sorted and measured while I kept notes.  We had the pile sorted by 11:30 am, then drove home.