A Tiny Salamander Appears

As winter draws near, it will be time for many terrestrial salamanders to reduce their surface activity and switch to their underground retreats. While some salamanders will use underground burrow networks created by small mammals, others will create their own.

Some members of the red-backed salamander species (Plethodon cinereus) will especially need to find a retreat soon. Starting in August, neonates hatched from eggs suspended in crevices inside logs, under rocks, and underground. These tiny salamanders are barely 25mm long. After an average of 6 weeks of gestation in eggs, the salamanders (depending on latitude) have only a few months before winter sets in. During this time, they disperse from the nest, forage, and find areas to overwinter.

Female P. cinereus typically lay their eggs (collectively called a clutch) in late spring and early summer; however, it isn't uncommon for females to oviposit later in the year. The number of eggs in the clutch ranges from 1-14 and is often correlated to the size of the female. Unlike males that mate each year, female P. cinereus reproduce biennially. Developing eggs, and eventually brooding them, is energetically expensive. Clutches that aren't brooded have a higher chance of being eaten, as the brooding female will lunge, bite, and snap at other salamander intruders. In some cases, conspecifics (members of the same species) will cannibalize eggs due to their energy content and nutrients.

Here in the Northeast, winter is quickly approaching, so lets hope this year's neonates are able to find retreats deep enough that they don't freeze.

References
Petranka, J. W. 1998. Salamanders of the United States and Canada. Smithsonian Institution Press, Washington, DC. 576 pp. 

Birds and the Bees, Sallies and the Streams

Well, not streams per se. But, with it being the season of pollen, green-up, and breeding comes the great breeding migration of the Spotted Salamander (Ambystoma maculatum) and the hatching of the Marble Salamander (Ambystoma opacum). Since the winter was so warm, breeding came early. In February, larvae of both species were swimming around in the vernal pools of Piedmont.

 A Spotted Salamander egg mass floating and hidden among vegetation.

The Marbled and Spotted Salamander have larvae that are deposited as eggs into vernal pools throughout the Southeast,  parts of the Midwest, and parts of New England. The Spotted Salamander's distribution also reaches into areas of Canada (Conant & Collins, 1998). Vernal pools, sometimes called ephemeral ponds, are seasonal wetland depressions found in woodlands. They fill during the winter and spring, and they dry during the summer and fall. Because they dry out, no fish can inhabit them--perfect breeding grounds for amphibians.

In the Piedmont of North Carolina, the hatching of the eggs for both species occurs simultaneously, and it can be difficult to distinguish between the two larvae. However, the Marbled Salamander larvae have black pigment on their throats and are typically larger (Mitchell & Gibbons, 2010). Both species have bushy external gills, tails for swimming, and two well developed forelimbs. Hind limbs develop during the larvae stage.

 Two Marbled Salamander larvae. 

Notice the tiny hind limbs and external gills.

The fascinating thing about these two species is not their aquatic larvae. Instead, it is the amazing journey the adults undergo in order to mate every year to two years. Both species are the only salamanders to mate on land. Marbled Salamanders migrate after mating occurs in October or November, and they lay their eggs in the dried ephemeral ponds. The eggs will only hatch after being inundated (Petranka, 1998).

 A Salamander larvae in its natural habitat, 

unaware of the looming net about to scoop it up!

Even more dramatic than that, Spotted Salamanders will migrate to breeding grounds during moist nights in late winter and early spring and will lay their eggs in flooded pools. It is unknown as to how salamanders orient themselves directionally, but they can travel great distances (200m-500m) to meet for the mating season (Petranka, 1998). For something only 22cm, that is a long way to go! Imagine having to go 900 to 2250 times our body size to find a mate.

 An adult Spotted Salamander. Found under a log

next to the vernal pool.

Unfortunately, given the migration patterns of the salamanders, there are great concerns for the survival and conservation of the two species. Besides the loss of ephemeral pools, habitat fragmentation by roads has isolated adult habitats from breeding grounds. With the small size and slow movement of salamanders, it is easy for them to be killed by motorists.

Hopefully you will have the chance to see one of these fantastic creatures! The best part is that they can be as far away as your backyard or local park.

Works Cited

Conant, R. and J.T. Collins. 1998. Reptiles and Amphibians of Eastern/Central North America. Houghton Mifflin Company, Boston, MA.

Mitchell, J.M. and W. Gibbons. 2010. Salamanders of the Southeast. University of Georgia Press, Athens, GA.

Petranka, J.W. 1998. Salamanders of the United States and Canada. Smithsonian Institution Press, Washington D.C.

Normal Mountain Activities

Well, this is the first post of what hopefully will become a good record of the adventures I've gotten to do as a budding ecologist (and the lessons I've learned from them). I'm not sure how frequent these posts will be, but nonetheless, stay tuned.


This past summer, I did what the average person does in the mountains of North Carolina--I looked for giant salamanders. Along with folks from the NC Wildlife Commission and the NC Zoo, surveys were conducted to find the giant salamanders. The elusive critter the surveys were aimed at was the Hellbender (Cryptobranchus alliganiensis). Don't worry, this isn't a monster that can manipulate the fires of the inferno (perhaps I've watched too many episodes of Avatar the Last Airbender). Their genus name is derived from kryptos "hidden" and branchos "gills". This accurately describes the folds of skin that cover the areas of oxygen exchange. Perhaps what common name you might enjoy even more is the "Snot Otter." These creatures win no conventional beauty contests.

Hellbenders occupy swift moving streams in the Appalachian and Ozark mountains

as well as eastern parts of the Mississippi drainage.

These large, ancient salamanders can get up to 74 cm (29 in) when adults. In the clean waters they inhabit, Hellbenders stay hidden under rocks on the bottom, and they feed on anything from insects to crayfish. When competition is stiff or territory is trespassed, they will also eat each other. 

Awaiting size measurements

Hellbenders are important because of their role in the stream ecosystem, but they are also significant because they are "indicator" species. When water quality continues to decline, these dwellers of the creek begin to disappear. As you can imagine with the ever-expanding reach of human development, the streams Hellbenders inhabit are becoming dirty and chemically unfit for them to survive. This has led to drastic declines in Hellbender populations across their geographic distribution. They are the canary in the coal mine as far as these bodies of water are concerned.

The surveys I participated in recorded a  variety of information to determine the age, gender, and health of individuals that made up a population. Along with Passive Integrated Transponders (PIT) tags, this information helps monitor and assess the status of the population. PIT tags are tiny devices (essentially RFID chips) that are carefully inserted into the Hellbenders, and, with a tag reader, researchers merely have to walk along the stream bank to survey for past individuals. Data like this can give a sense of how long individuals survive as well as how the demographics of the population are changing.

So, my experience with these fascinating salamanders involved the fun task of snorkeling in mountain streams. As it was only the second time I've been snorkeling, the plain act of snorkeling was exciting in and of itself. Now, on top of that, I was searching for rare, giant salamanders. Never have rocks and boulders looked so much like presents to be unwrapped, for it was definitely a surprise to lift a rock and see these creatures looking back up at you! Catching a Hellbender is a tricky ordeal too. It's like trying to grab a wet bar of soap, except Hellbenders are even slimier and more slippery than soap--not too mention they tried their best wriggle out of your hands.

Never will mountain streams be perceived the same way again

Hopefully as more attention gets drawn to Hellbenders, more people will be concerned about the conservation of their habitat--a habitat that is home to numerous other salamander species, unique fish, and other wildlife.





For more information look at hellbenders.org or see Salamanders of the United States and Canada by James Petranka.