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| One of 4 Ruffed Grouse seen driving to field sites |
Southern Appalachia is beautiful:
That beautiful view is desirable for people to build houses, especially second homes. To get to those houses and beautiful views most people do not backpack in, leaving little more than a foot path; people build more roads. These roads have potential impacts on many fauna, and not just from increased direct encounters with cars. The road cuts clear sections of forests making gaps in the landscape and change the hydrology (water flow). The influence of increasing hill slope roads on salamanders has not yet been studied, so the impact is unclear. Anyone looking for a research project? =]
In March we headed to several spots throughout the Coweeta basin to set up new study sites. The sites are set along a natural moisture gradient. The more eastern part of the basin gets up to 60% more water than the western part. This allows us to look at salamander fitness (health) and abundance in a wide range of environmental conditions over a small area. March in the mountains can still be quite cool (see fog in picture above), but a few salamanders where up and about. They were moving pretty slowly (Desmognathus ocoee on the left with a vibrant orange cheek and juvenile Plethodon hybrid on the right).
While out and about hiking for sites I also spotted some fun fungi; Turkey Tails (on the left) and Earthstars (or false Earthstars, on the right. Alas my mycology identification is quite limited and I did not know what to look for to tell the difference).
The field season for salamanders really kicked into gear at the beginning of April. This spring and summer (in addition to continuing work on some previous studies) I am examining the fitness of larval salamanders in areas where Rhododendron (the midstory canopy) has been removed. Larval salamanders are notoriously hard to recapture so, we set up some in-stream cages. These cages are actually mesh terrariums set up to look like the bottom of the stream.
We then collected larval shovel-nose (Desmognathus marmoratus) and black-belly salamanders (Desmognathus quadramaulatus). These two species can be hard to tell apart, especially in larval form but they are the most abundant and largest larval salamanders in the streams. These animals remain in larval form with gills for several years and stay close to or in the water as adults. We will periodically go back to the cages to make sure they have not been washed out by a large rainstorm and to take measurements.
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| Small adult shovel-nose salamander |
While looking for larval salamanders we found a few spunky crawfish and one with babies!
We also found a few additional adult species including this stunning Spring salamander (Gyrinophilus porphyriticus). [More on these salamanders later]. We also found some brightly colored male, Blue Ridge Two Lined salamanders (Eurycea wilderae; not pictured here). These males were in the streams waiting for females to breed.
The first week of April also marked the beginning of nocturnal sampling. A long term project for our lab involves examining habitat changes to a small area when salamanders are removed. So far we have noticed increased density of ants (salamander's primary food source) but are eagerly awaiting vegetation survey results.
Unfortunately, sometimes things can get lost in translation when projects are handed down to other lab members so the first night out we could not find some of the sites! It was raining, so we managed to scrounge up a few really awesome salamanders any way:
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| Spring salamander (G. porphyriticus) |
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| Red-legged salamander (Plethodon shermani) |
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| Black-belly salamander, part way out on the hunt! (D. quadramaculatus) |
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| These two strikingly different looking salamanders were found within a few meters of each other! |
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| Pretty gold spotted Ocoee salamander (D. ocoee) |
After consulting some maps, we did manage to find the sites on the second night of sampling and saw this beautiful red legged girl (with a cool red blush on her cheeks) eating a centipede!
Out for fun and a Herpetolgoy class field trip on Saturday yielded some phenomenal encounters. First, I came across a Two-lined salamander (Eurycea sp.) egg mass!! These eggs are laid on the bottom of flat rocks in small streams. Usually the female will remain with the egg mass for protection. In this case she likely swam away when I was flipping rocks, but she probably went back.
Then someone managed to net a Chestnut Lamprey (Ichthyomyzon castaneus, pictured below)! Until this trip I had no idea that there were freshwater lampreys native to northern Georgia. Lampreys are a type of jawless fish. As adults they attach themselves to a fish host where they feed on blood. A different species (the Sea Lamprey) is considered a pest in the Great Lakes region where it has no natural predators and has become invasive.
A few people managed to catch some relatively robust two-lined salamanders in the stream (below). These animals are a bit larger than any Blue Ridge Two-Lined salamanders (Eurycea wilderae) I have seen before, but in this region, that's what they look like (we consulted an expert)! There is a lot of variation in two-lined salamanders and likely some undescribed species based on genetic diversity.
The final fabulous find of stream searching was a Hellbender (Cryptobranchus alleganiensis)!!!!! This giant salamander is sometimes called a Snot Otter and is native to the eastern United States. It's closest relatives (genetically) are the Chinese and Japanese Giant Salamanders which can reach 5 feet in length!! Here, Hellbenders reach about 2 feet in length. This one was about 10-12 inches. They use their highly flattened bodies and large toes to easily move along the bottom of fast flowing streams. They also have folds of skin along their sides to collect more oxygen from the water. They also have a lateral line (similar to fish) which they use to detect vibrations in the water.
Hellbenders have a fascinating mechanism for catching prey. They expand their hyobranchial apparatus in their throat and creating a rapid suction. While we were holding the one we caught, it expanded it's throat a few times (pictured below). Hellbenders are experiencing widespread declines likely linked to habitat destruction.
To top off an already exciting day, after dark we visited a wet rock face at the Coweeta Hydrologic Laboratory in North Carolina. The rock was (literally) crawling with life from a snail hiding in the moss to an abundance of Ocoee (Desmognathus ocoee) and Seal Salamanders (D. monticola). The Ocoee salamanders had widely variably color patterns, this one with yellow spots was one of my favorites (below). We also saw several larval Ocoee Salamanders, which were less than two centimeters long with small bright white patched on either side of their head (their gills). [I did get a picture, but they are so small, it is almost impossible to see in the picture.] Also present were THREE Spring Salamanders out hunting (picture of one below). I have never seen that many in one place before!! What were they hunting? The Ocoee Salamanders of course.
No post of mine is complete without a few pictures of Plethodon! First is a small male salamander with gorgeous red legs. He is probably one of the best examples of what a Red-Legged Salamander (Plethodon shermani) looks like. In the center is a tiny salamander, only about 2 centimeters long! And finally a beautiful example of a hybrid salamander between the local Red Legged Salamander (P. shermani)and Southern Appalachian Salamander (P. teyahalee) with both red legs and white spots (plus a little bit of red blush on the cheek which happens sometimes with theRed Legged Salamanders). We see a range of phenotypes for hybrids from this strong spotting and red color to no color or spots at all.
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