New Class Finds Herps at the Nature Center

If I could choose any time to take new Master Naturalists into the field looking for herps, it would not be at the end of summer. The Fort Worth Nature Center & Refuge rarely disappoints, and so we found several reptiles and amphibians yesterday, despite the odds.

I have been teaching incoming Master Naturalists at the Cross Timbers chapter about reptiles and amphibians (herps) for years, and it is always a great experience. Some of them already have some interest and experience with these animals and almost all have the curiosity and enthusiasm that makes for a great class.

A great class but I wondered if it would be a great field trip. Since late July, high temperatures have been at or above 100F every day, with three exceptions. On the Saturday of our outing, it had been 51 days without rain, so I wondered if we would be able to find something.

Starting at 9:00am, the first of three groups checked the Marsh Boardwalk. Sometimes we find green treefrogs stuck to plant stems and leaves, trying to get some sleep. We did not see treefrogs, though later the next group would find a beautiful female Texas spiny lizard in the ambush position on a big willow tree trunk.

We headed down the old two track road into the bottomlands. Brent Franklin, dragonfly expert and part of the leadership of the Cross Timbers Master Naturalists, was with us. So was Shaylin Daji, a guy who completed training in years past and who has a real interest and talent for finding herps. You couldn’t find better co-leaders on a walk like this.

We almost always find something as we walk down that road. On our mid-morning walk, Brent and Shay found a young skink under a log alongside the road. It was either a five-lined skink (Plestiodon fasciatus) or a broad-headed skink (Plestiodon fasciatus) – determining which one requires looking at details of scalation on the head, and we weren’t able to get that kind of close look.

On the walk with the last group of the day, we found what was undoubtedly the same skink again, in the same place. We had a sort of Three Stooges moment as Brent, Shay, and I tried to get the lizard to stop for a moment out in the open, or perhaps we could capture it. The hardest part may be the care required to make sure that we did not break the skink’s tail off. I would much prefer to see it escape than to do that. The skink could grow another tail, but it’s not like grabbing one at Wal-Mart on the “body parts” aisle. Lizard tails require time and energy to grow or re-grow, and losing the tail puts them at a disadvantage.

So we got several good glimpses at this lizard, but nothing more. It was young and so it still had the bright blue tail that juveniles have, with the color fading as the skink reaches maturity. Same with the bright lines on a dark body; females keep some semblance of lines in adulthood, while the males become a plain, light brown. Their jowls have an orange tint which becomes brighter during breeding season.

The other thing we found near the road was a shed snake skin, with the head and first half or more of the skin intact. Often we can identify the snake (or narrow down the possibilities) by carefully examining it. Are the dorsal scales bigger, or smaller? Are they keeled? Can we detect any pattern in the shed skin? Looking at it in the field, we agreed that the dorsal scales looked smooth and there was a suggestion of a striped pattern.

Later, I dampened the skin to make it flexible and cut it at the edge of the dorsal scales so the tube of skin could be laid it and examined better. The trace of pattern now seemed more like alternating patches of dark and light (blotches down the back) and a really close look seems to show slight keels in the scales in the middle of the back. What was puzzling in the field seems likely to have been from a juvenile western ratsnake (Pantherophis obsoletus).

The bottomland forest is an area with ash, cottonwood, hackberry, and other trees that can withstand periodic flooding. The ground is covered with a latticework of downed branches and logs, and that ordinarily provides lots of opportunities to see herps and other critters. The soil was dry, even under pieces of bark or branches that we turned over.

But at some point, someone flushed a mouse (my best guess was white-footed mouse, Peromyscus leucopus but it’s only a guess) that ran up the base of an ash tree under loose bark. As we were trying to get a look without pulling bark off the tree, someone said “Copperhead!” and our attention quickly shifted to a beautiful snake at the base of the tree.

As it tried to get away, I used a snake hook to try to pull the copperhead back to the tree. I thought that, with a tree trunk behind it, the snake might feel less vulnerable and stop to see what threat it was facing. My goal was for the other participants to get a good look at the snake before we let it go its way. Often a pit viper such as this one, after being pulled back a time or two with a hook, will coil up momentarily. Not this one. This broad-banded copperhead (Agkistrodon laticinctus, according to the latest taxonomy) got under a big log and there was no getting it out.

From the other side of the log, Shay was able to help the others see a bit of the snake’s coil under the log, but the copperhead stayed put. We found him or her as each of the subsequent two groups of Master Naturalists came through the area, sometimes with the snout visible and watching for danger, but never willing to emerge.

Participants found a rough earthsnake or two (Haldea striatula) and a couple of Gulf Coast toads (Incilius nebulifer), and – being Master Naturalists – they admired all kinds of other things including the ironclad beetle (Zopherus nodulosus haldemani), a recluse spider (Loxosceles sp.), and a wolf spider (probably Hogna sp.)

By early afternoon the temperature was reaching 100 degrees and we were wrapping up a good day at the nature center, really a better outing than I might have expected.

I also managed to put in the good word for keeping field notes with some of the groups. Because it would be hard in that context to stop frequently and get the notebook out, I dictated some things about the location, weather, and then each of the herps we found and what they were doing. I warned the students that dictating notes runs the risk that you never get around to transcribing them into a notebook.

I also promoted the use of good field guides. As wonderful as iNaturalist is, I don’t think it would give us information about the scale differences that would let us determine which of the skinks we saw. And good field guides provide some natural history information that can be helpful in the field. As I told the incoming Master Naturalists, knowing about things like habitat or diel (day vs. night, etc.) activity can help you know how to look for certain species.

So, a “thank you” to the Master Naturalists for hanging in there, combing through the woodland, asking good questions, and being good observers on this outing. Hope to see you again.