Trip leader – Bill Gee

Participants – Martin Carmichael
Sarah Peterson
Tristin Whetstine
Diana Dawson
Caleb Mundwiller
Erica Hroblok
Angie Wooden

Permit number 2023-004

This trip had four goals. The main goal was to replace the batteries and memory card in the bat roost logger located next to the big guano pile at the Lunch Room. This prepares the logger for the upcoming maternity colony which should start moving in around the end of April.

The second goal was to replace batteries and memory card in the cave intrusion detector located near the ladder. Goal three was to collect some water samples for Tyler Huth. He is doing isotope analysis. The fourth was to introduce some new cavers to Carroll Cave. All four goals were accomplished during the trip.

Tristin Whetstine drove to the campground Friday evening and spent the night. It was chilly, with morning low on Saturday around 20F. I drove to the cave early Saturday morning arriving about 7:50am, shortly after sunrise.

The low temperature created a problem that Tristin and I struggled with for half an hour. It rained at the site earlier in the week. Not much, just a few tenths of an inch, but enough to get water in the combination padlocks. I had to work the lock at the road gate to get it to open. Rather than risk it freezing again, I left that gate chained and unlocked for when everyone else arrived.

The lock on the silo was much more difficult. We banged on it with some rocks but made little progress. The worst problem was the lift gate on the topper of my truck. It also was frozen shut! I have a propane heater to thaw locks but could not get to it. We pried and hammer on that lock for 20 minutes and made only a bit of progress. Eventually I moved my truck so that the back was facing the sun. About ten minutes later the lock popped open. In the meantime Tristin had managed to unlock the silo.

I started the heater in the back of my truck, then unlocked the cave and hung my rope. The cave was, as usual for winter, blowing out very strongly. We had a major surprise when I went down into the basement area. There were two adult grotto salamanders in the puddle next to the shaft. I have never seen salamanders there. Tristin got a few photos of them. By the time we started getting on the rope, the salamanders had moved somewhere else.

The rest of the participants arrived between 8:30 and 9:00am. Everyone geared up. Everyone had their own seat harness and rappel device, so the loaners I brought did not need to be used. Several people used cable sleeves for the climb out. I gave all of them a quick lesson on how the sleeves work.

Martin was the first person to go down the shaft at 9:40am. I stayed at the top to help everyone get on the rope safely. I was the last person down at about 10:30am.

I gave a brief talk about the geography of the cave, then we all set off for the first objective. Traveling through the Water Barrier went well. At the first riffle downstream from the Water Barrier, I turned over some rocks and quickly found a few isopods. I made sure everyone got a good look at them. We saw several grotto salamanders around guano pile 3, and another group near guano pile 6. All of the guano gauges on all of the piles were completely clean.

We arrived at the bat roost logger at noon. Changing the batteries and memory card took only a few minutes. Everyone moved over to the Lunch Room and had lunch. The Lunch Room waterfall was flowing, which surprised me. I did not think there had been that much rain in the area. This is only the third time I have ever seen it flowing.

Several people wandered around a bit just exploring the general area. We left for the return trip at 12:40pm. On the way back Angie was running out of gas. Martin stayed with her while the rest of us went on to Thunder Falls. We arrived there about 1:50, which is fairly fast. The water level in Thunder River was about normal. Martin and Angie joined us about 10 or 15 minutes later. While the others were checking out the waterfall, I collected a water sample.

Back at the ladder, I collected a water sample from the rain at the bottom of the shaft. I also changed the batteries and memory card in the cave intrusion detector. Martin climbed out first and stayed at the top of the ladder to help everyone get out of the shaft safely. I made sure everyone was set for the climb. I was the last one out. As I climbed, I collected another water sample about 40 feet up from the bottom of the shaft.

Everyone was out of the cave by 2:45pm. It was sunny outside but only a few degrees above freezing. It had not warmed up much during the day. Martin and I derigged the shaft. We left the hatch open for a while to warm up the silo for changing.

By 3:30pm we were all ready to leave. I was the last person to leave the site, making sure the road gate was properly locked. We all had an early dinner at El Caporal in Camdenton. I was on the road back home by 5:00pm.

The data file from the bat roost logger appears to be empty. I do not have software to fully analyze it. I will send it to Vona Kuczynska for her to look at. The data file is normally 4 gigabytes of uncompressible data, but this one reduced down to under 20 megabytes. When I looked at the old batteries at home, I saw the one of them had only 95mv on open circuit. That is not good. Even a completely dead battery of that type should show over 2 volts on an open circuit. I suspect the roost logger did not run for more than a month or two. Analysis of the data file should show how long it ran.

Analysis of the data was done by Vona Kuczyynska. The data shows the logger ran from 29 October to 22 November, just a bit less than one month. In that time it recorded four bats. A very low population of bats is expected at that time of year.

Next time we buy batteries, it will not be from Amazon.

Several videos on YouTube:
https://youtube.com/playlist?list=PLD1S1mFlMqVSGqvv28I0c2e4vkzsV0t_X

Photos from several participants at:
https://photos.app.goo.gl/Nm9uoHRBNSQt95Gu5