Trip report Carroll Cave Bat Census 26 October 2024

Participants – Bill Gee (trip leader)
Martin Carmichael
Peter Schnegelberger
Shane McCurdy

Time in = 9:10am
Time out = 6:30pm

This was the annual bat census trip in Carroll Cave. We count other critters, too. Indeed, given the population drop in bats we are now counting far more other critters. The bat population is getting down to near zero.

This trip originally had seven people signed up. Three dropped out just a few days before. Martin Carmichael and I tried to recruit a couple of additional people but had no takers.

I drove to the campground Friday afternoon, arriving at 3:30pm. Peter had arrived just a few minutes before me. I parked my camper beside the power post. Peter and I got into the container to check the charge status on the mower. The grass around most of the area is quite high.

The mower was completely discharged. Unplugging and plugging the charge cable did not turn anything on. Pressing the button on the charger shows a series of numbers which might be an error code. We did not write it down.

The battery string trimmer, on the other hand, was fully charged and ready to go. I used it to clear an area around my camper and Peter used it to clear an area for his tent.

I rigged the rope in the shaft. I noticed that the puddle which usually sits at the bottom of the basement area was completly dry. Not even muddy – it was just dust. The area has 3/10 of an inch of rain Thursday and early Friday, but you could not tell.

The next morning Martin arrived about sunrise. The temperature was a bit chilly, around 38 degrees, so we did not get our cave gear on for an hour. Shane arrived about the time we were ready to cave, around 8:30am.

Everyone was geared up by 9:00am. We started down the shaft at 9:15am and were all in the cave by 9:45. With only four people I figured we could move fairly fast. The first stop was a riffe just downstream rom the Water Barrier. Every year we stop at this riffle and count isopods. This year the isopod population was a bit less than usual.

From there we proceeded on down Carroll River. At each guano pile we photographed and documented the state of the guano gauges. Martin brought along a disposable water bottle. Instead of taking each gauge down to the stream to clean off, we filled the water bottle with stream water and cleaned the gauges at the pile. It was much more convenient.

The guano gauges had the normal pattern of use. Gauges 15a and 15b were, as usual, completely covered to substantial depth. The flagging tape label on them was buried in new guano.

We arrived at the Lunch Room at 11:30. After a good meal we started the bat count at 12:00. The passage has not got any easier to navigate. It is several thousand feet of slippery, boot-sucking mud.

The bat count came up with three single bats and a small cluster of perhaps a dozen individuals. We saw far more salamanders and sculpins. We also found a lot of isopods in some stream riffles which we did not count.

We arrived at the Mountain Room about 2:30pm. I went around and photographed the guano guages in there. As usual they had no activity. The return trip started at 3:15pm. We made good time back to the ladder that goes up to the Turnpike. Once in the Turnpike we slowed down. Peter was running out of gas.

Out of the Turnpike at about 5:00pm. A quick break to clean off the worst of the mud, then on to the ladder. It was slow going especially through the two sloppy mud stream crossings. Back at the ladder about 6:15.

We all geared up and started the climb. Martin and Shane went first, then Peter and me last. Peter used the last of his energy getting up the ladder. It was tough but he did it on his own power. Everyone was out of the cave by 6:45.

To save weight on the climb, we tied a couple of packs to the end of the rope. Martin and I pulled up the packs by hand while Peter walked the rope out into the field. Everyone changed out of muddy cave gear. Martin went to town for dinner and then on home while Shane, Peter and I stayed the night.

Bill Gee

=========== Data Section ===============

Bat and critter counts:
Lunch Room to 6000 foot: 12:08pm – Zero bats, 1 fish
6000 to 5000: 12:35pm – 11 sculpins, 10 salamanders
5000 to 4500: 12:48pm – 16 sculpins, 1 bat (tricolor)
4500 to 4000: 1:03pm – 14 sculpins, 3 salamanders
4000 to 3500: 1:16pm – 5 sculpins, 1 perch about 10 cm, 1 salamander
3500 to 3000: 1:26pm – 2 bats (1 tricolor, 1 gray), 1 salamander
3000 to 2500: 1:38pm – 1 sculpin, 1 salamander, lots of isopods not counted or measured
2500 to 2000: 1:47pm – 1 bat, 1 perch, 3 sculpins
2000 to 1500: 1:54pm- 1 sculpin
1500 to 1000: 2:01pm – 4 salamanders, 1 bat, 1 sculpin
1000 to 500: 2:09pm – 10 bats in a small cluster, 1 sculpin
500 to Mountain Room: – 2:17pm – Nothing
Mountain Room: 1 crayfish, 5 sculpins, 1 unknown fish

Isopod count:
2mm = 1
3mm = 6
4mm = 1
5mm = 4
7mm = 1

Guano gauges:
Guano gauge 1 = 20% coverage 2mm.
Guano gauge 2 = 30% coverage 2mm.
Guano gauge 3 = 50% coverage 3mm.

1 fish in the stream.

Guano gauge 4a = 10% coverage 2mm.
Guano gauge 4b = 95% coverage 3mm.
Guano gauge 5 = light dust.
Guano gauge 6 = 30% coverage 2mm.
Guano gauge 7 = Completely clean.
Guano gauge 8 = Completely clean.
Guano gauge 11 = One turd.
Guano gauge 12a = 80% coverage 3mm.
Guano gauge 12b = 90% coverage 4mm.
Gauno gauge 13 = One turd.
Guano gauge 14a = Completely clean.
Guano gauge 14b = Completely clean.
Guano gauge 15a = 100% coverage 6mm.
Guano gauge 15b = 100% coverage 6mm.
Guano gauge 16 = Completely clean
Guano gauge 30 = Completely clean
Guano gauge 31 = Completely clean
Guano gauge 32 = Completely clean