April 9, 2013

Cold Morning, Cool Salamanders

Last Saturday we woke up to temperatures in the low 30's but the forecasters said that it would warm up quite a bit. We had to be home by noon, so we  headed to a vernal pool at one of the local metro parks, where we were hoping to maybe see a salamander or two.

Vernal pools are small ponds that are usually dry by mid-summer. On warm, rainy nights in March and early April, certain species of salamanders  head to them en masse to find mates and lay their eggs. (Spotted salamanders are probably the best known species in Ohio that does this.) What do these ponds have that is so attractive to these animals? Well, it is mainly what they don't have that is attractive: fish! Salamander eggs (and probably some of the adults) would promptly be eaten if fish were present.

Salamanders are secretive animals that mostly spend their days hiding under rocks or logs or buried in moist earth. Breeding season is the only time many of them do much moving around, and that activity lasts for just a brief time. For some really interesting information about salamander reproduction, much of which I was not familiar with, go on over to TrekOhio at this link

Here is something else I have learned about salamanders: The awesome photos in magazines and field guides are just possibly a little bit staged. I'm not necessarily sayin' that they have been cleaned up and stuck into aquariums decorated with perfectly contrasting leaves and moss, but these critters aren't all that photogenic where they are normally hanging out, like under rocks and logs! 

Anyway, on with the adventure! Here is a picture of the vernal pool that we visited--perfect for salamander sex. It is fairly shallow and tucked into a densely wooded ravine. We were too late for the nocturnal mating show, which usually occurs in March, but we thought that there might still be a couple of the critters in the area that hadn't dispersed underground or off in the moist leaf litter. 

So we started to carefully turn over fallen logs, making sure that we replaced them exactly as we found them. We were totally amazed at the number and variety of salamanders that we found! Since it was so cold, most of them were very sluggish and didn't move. I was very reticent to stress them other than turning over their logs, so I didn't try to pose them which is why some look kind of squished. They were just fine, though, alive but not lively!

Under the first log we checked was a nice spotted salamander, about 6" long. It is a mole salamander; these animals spend most of their lives underground and have well-developed lungs. They don't breed until they are 4 or 5 years old and they may live for 20 years! This very cool looking animal is probably abundant in many parts of Ohio, but is seldom seen except in breeding season when they head for vernal pools. 

We found several Jefferson salamanders, which, like the spotted, are mole salamanders. Courtship, breeding and egg laying all occur underwater, mainly in vernal pools. This one could use a rinse for a better picture, but this will have to do!

Probably the most common salamander in Ohio is the redback. We found several of these, and they are in the group of lungless salamanders. This means that oxygen intake occurs only through the lining of the mouth and moist skin. They have to stay moist or they will suffocate, but some will drown if submerged in water for very long. They are small and are entirely land dwelling, even during breeding. They lay their eggs in summer underneath a moist rock or log. They have gills while they are developing in the egg, but the gills shrivel up within 24 to 48 hours of when they hatch.

Redback salamanders have a color phase called leadback, in which the animal is entirely dark gray or black. These two color phases can occur together, and that is probably what is shown in this picture:

We tried to convince ourselves that the dark one was a small-mouthed salamander but since it was with the redback we figured it probably is a leadback. The shapes of their heads look a little bit different, but this picture isn't the best angle. If any herpetologists are reading this and have an opinion, let us know!

The last species that we found was the southern two-lined salamander, which is also in the lungless group. This animal lives and breeds in small rocky woodland streams, springs or seeps. When we hiked past just such a stream, we paused to turn over a few flat rocks and with little effort found one! They are typically easy to find but difficult to catch and hold. I think the cold temperatures once again worked in our favor because this individual was pretty cooperative.

To sum up this adventure, I was totally amazed by the abundance of salamanders in this small wooded ravine. In about 15 minutes of turning over logs and rocks we found probably a dozen individuals of 4 species, which is 11 more individuals than I've found previously in Ohio, mainly because I've never looked for them before!

Ohio has 25 species of salamanders and there are more salamanders in North America than in all the rest of the world. According to the Amphibians of Ohio Field Guide, a small booklet published by the Ohio Division of Wildlife, "the total biomass--overall weight--of Ohio's salamanders exceeds that of all our other amphibians combined, in spite of the fact that most people never even see one."

Another quote from the DoW amphibians booklet: "As with all Ohio wildlife, the only real threat to their continued existence is habitat degradation and destruction. Only by conserving suitable habitat today will we enable future generations to study and enjoy Ohio's amphibians."

Here is a good link for more information about Ohio's salamanders: http://ohioamphibians.com/salamanders/Salamanders.html

1 comment:

  1. I was shocked to learn that the total biomass of Ohio salamanders exceeds that of all the other amphibians combined since I never see them! I've not turned over logs looking form them, but I'm glad that you did because I enjoyed your photos.