15 October 2007

Another March Across the Ah-ah

09 October 2007 -- Breakdown Basement and Spotted Pavement Caves

Image of me standing above Spotted Basement Cave. Image Credit: Ara Kooser.

Today, our mission was to deploy traps at two caves. We arrived at our first cave and we decided not to sample there. I’m calling this cave Breakdown Basement Cave. This cave was characterized by large person to car sized boulders littered on the ground as breakdown. This cave contained extensive dry and deflated guano, but I did not observe any recent guano deposition. Because of this, I concluded this cave was not a good candidate for survey. Additionally, we went to the first part of the cave where it constricted narrowly and the team decided the breakdown surrounding the passage was unsafe. The lack of nutrient availability coupled with potential safety hazards resulted in us deciding not to sample at this cave.

Once we made the determination this was a less than favorable cave to survey, we proceeded across the lava flow to our second cave. I’m calling this cave Spotted Pavement Cave. This cave was maze-like with a pahoehoe ribbon floor and contained multiple braids along one major passage. We decided to sample within this cave. While our initial time constrained searched did not reveal any invertebrate activity, we deployed baited pitfall traps.

Chrystal formations observed at ground level at the back of Spotted Pavement Cave.

I documented a light deposition of bat guano throughout the front half of this cave. I believe nutrient availability may limit cave diversity. I expect our additional survey when we collect traps will likely provide us with valuable insights into the diversity of this system. We know from previous work there were several invertebrates inventoried from this cave. However, I think many of these species were surface dwelling organisms, and thus were not cave-adapted or limited.

Over the past two years, I have studied this cave as part of my cave detection research. I’ve observed bat maternity activity within this cave. It contains a summer roost of Townsend's Big-eared bats. While conducting our surveys on this trip, I did not record any evidence of recent use of this cave as a Townsend big-eared bat maternity roost.

Also, on two occasions during the cave detection research, I’ve observed Rhadine beetles in the cave dark zone. I am quite eager to find out what occurs in this cave. In four days, we will return.

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