24 October 2020 Bat Census Trip Report

Participants: – Bill Gee (trip leader)
Seth Colston
Kristen Godfrey
Isaac Smith
Vona Kuczynska
Jeanette Bailey

Time in – 10:20 a.m.
Time Out – 8:20 p.m.

This is the annual bat census trip that we run in October every year. This year we had some extra tasks and special participants. Vona is a biologist with the U.S. Fish and Wildlife Service who specializes in grey bats, and Jeanette is a biologist with Missouri Department of Conservation specializing in bat ecology. I was very please that both were able to make this trip.

I drove to the campground Friday afternoon arriving about dinner time. Seth and Kristen came in later, after I was already in bed. Saturday morning Jeanette and Vona arrived a few minutes after 9:00. Isaac was running late, arriving about 9:50.

The weather was cloudy, windy and rather chilly. We all geared up. For safety we hung a second rope in the shaft. Vona and Jeanette both used Petzl ASAPs as a safety device while rappeling, and that requires a second rope. The ASAPs are also useful as a safety device when climbing the ladder.

The bucket of cable sleeves that is normally in the silo was not present. A single sleeve was on the training cable in the upper part of the silo. Fortunately no one needed it! Kristen used it for her climb out. I suspect the bucket of sleeves is with Rick Hines for cleaning after the landowner trips on the previous two weekends.

Seth and Kristen went down the shaft first. Isaac was next. I help Vona and Jeanette get onto the rope, and then I went down as the last person. I was in the cave about 10:40am.

I downloaded the two data loggers at the ladder. We then started down Carroll Passage. I downloaded the data logger in Carroll River. We went through the Second Water Barrier. Just past the Water Barrier is a riffle in the stream where we counted and measured isopods. “Measure” is a bit too strong a word as we used an eyeball estimate of their length.

From there we proceeded to the guano piles. I made voice notes about the state of each one, and also took a photograph. The rest of the group looked around for other critters. They found quite a few grotto salamanders and cave fish, as noted in the data below.

We arrived at the Lunch Room about 1:30. Everyone had a big snack, or in Isaac’s case a full meal. The ceiling waterfall at the Lunch Room was not flowing, not even a drip.

The bat count starts at the Lunch Room. We left there about 2:00pm. At this point everyone put on face masks in anticipation of finding bats. As usual the count proceeds slowly. For the first few markers we found nothing in the way of bats. That has become the new normal.

The stream had some surprises for us. We saw quite a number of banded sculpins in the stream, and also a few bluegill. The bluegill were very emaciated, but the sculpins looked to be in moderate health. When we got to the Mountain Room, Isaac went around looking in the stream. Besides a large number of banded sculpins, he also saw some crayfish and pickerel frogs.

While counting bats, we occasionally turned over a random rock. We did not record count and size, but nearly every rock we looked at had some isopods on it. One rock that Jeanette looked at must have had a dozen or more on it. I could see them from where I was standing about 10 feet away.

We found several individual bats, all identified at greys. We saw two small clusters of grey bats. One was near and the other was just about 100 feet upstream from the 500 foot reflector. We have seen a cluster in that location for the last several years.

We arrived at the Mountain Room about 4:30. More snacks and water.

Vona has arranged for USFWS to loan a bat roost detector to the CCC for a year. That may be extended. This is a sonic detector which records ultrasonic sounds at regular intervals. We placed it in the Mountain Room aimed toward the Water Passage and slightly up. It should be able to sense almost any bat flying in or out of the cave. It will record 75 seconds of sound every 5 minutes. The recordings can be analyzed to determine what species of bats are present and approximately how many. We have never had good data on what species of bats use the cave, how many there are and when they are present. The sonic detector should go a long way to helping understand how bats use the cave.

We left the Mountain Room about 5:30 for the return trip. As usual, the return trip went much faster since we were not stopping to count anything. The trip through the Turnpike took just under 30 minutes, which is very fast. We got seriously slimy with the mud.

The trip back continued at a fairly fast pace. We arrived at the Thunder Falls shortcut about 7:30. Two hours from the Mountain Room, through the Turnpike and back to the entrance is not a record, but it is quite fast.

We had three Carroll Cave newbies on the trip, so a visit to Thunder Falls was required. The water level in Thunder River was right at normal. I went to download the stream level data logger. Seth and Isaac went to the bottom of Thunder Falls where Seth took some photos. Everyone cleaned up as best they cood in the pool just upstream from the falls.

Back at the ladder, we all geared up. Seth, Kristen and Isaac climbed out first. I helped Vona and Jeanette get their ASAPs on the rope. The three of us climbed together, with me bringing up the bottom. I was not able to climb at my usual rocket pace! That’s OK because Jeanette had a bit of trouble with her rig on the way up. We got it sorted out and finished with no trouble.

Everyone was out of the cave about 8:20 pm. We pulled up ropes and changed clothes. The weather was about 40 degrees with some breeze. It has been worse, but was plenty chilly anyway. I camped Saturday night and everyone else left for the drive home.

Analysis of the stream level data loggers shows no floods of any kind since early July. The level in Thunder River declined in a steady line from about 1.3 feet to just over 1.1 feet. The rain gauge shows about 2 inches of rain around the 10th of October and an inch around the first of August. There were no stream level changes associated with these rain events.

Bill Gee

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Miscellaneous:
Near Paradise Passage entrance. One surface accidental fish, maybe a bluegill. Emaciated, about 15cm long.

Bat Count:
Lunch Room to 6000: 2:00pm. Count is zero.
6000 – 5000: zero bats. 12 banded sculpins. Two salamanders. Several surface accidentals, probably bluegill.
5000 – 4500: 1 grey bat, 2 salamanders, 10 banded sculpins
4500 – 4000: Count is zero.
4000 – 3500: Seven salamanders. Eight sculpins. Unknown mammal track. Four grey bats. Three of them in one cluster and one hanging alone.
3500 – 3000: Three sculpins. 1 grey bat. Some beetles, and maybe a beetle larvae.
3000 – 2500: One bat flying. Six sculpins.
2500 – 2000: Two bats hanging. One banded sculpin. Jeanette turned over a 6 inch rock and it had a dozen or more idopods.
2000 – 1500: Two small clusters of about 4 individuals each. Three individual bats. No salamanders or fish.
1500 – 1000: One sculpin
1000 – 500: A cluster of bats about 100 feet upstream from 500 ft. reflector. Another smaller cluster of bats a little further upstream. 3 single bats, identified as grey. 1 sculpin. Several flying bats. Five sculpins
500 – Mountain Room: three tri-color bats. Beetles and lots of fungus gnats.
At the Mountain Room: 38 banded sculpins, 6 pickeral frogs, 2 crayfish.

Isopod count:
All five tiles in the riffle were blank.

2mm = 2
3mm = 2
4mm = 3
5mm = 5
7mm = 1

We saw one grotto salamander and two cave fish along the riffle. There were three unidentified critters that might be some form of planaria or flatworm. They were small, only 1 or 2 millimeters long.

Guano gauges:
Guano gauge 1 = completely blank
Guano gauge 2 = 40% coverage, 1 or 2mm.
Guano gauge 3 = completely blank

One adult grotto salamander on pile two. Another about half way between 1 and 2, length 10cm. Another 8cm grotto salamander. 3 cave fish, one small about 3cm, another larger about 4cm. 1 salamander in the stream.

Guano gauge 4a = 95% coverage, 4mm
Guano gauge 4b = 70% coverage, 3mm
Guano gauge 5 = Completely clean.
Guano gauge 6 = 15% coverage, 1mm depth
Guano gauge 7 = Completely clean.
Guano gauge 8 = One small spot. Left over from last year.

Guano gauge 11 = Completely clean
Guano gauge 12a = 80% coverage, 3mm. About half of the guano was dark black, the other half a medium grey.
Guano gauge 12b = 100% coverage, 8mm depth

Gauno gauge 13 = A few small turds.
Guano gauge 14a = Completely clean.
Guano gauge 14b = Completely clean.
Guano gauge 15a = 100% coverage, 7mm depth. Dripping over the edges.
Guano gauge 15b = 15% coverage, Isolated turds depth 1mm.

Two salamanders down by the stream.

Guano gauge 30 = Completely clean
Guano gauge 31 = Completely clean
Guano gauge 32 = Light dusting, probably from previous years.
Guano gauge 33 = Light dusting, probably from previous years.