Herp Hunting: Part 2 – Hellbenders and Hybrids

Previously, I wrote on the variable life histories of salamanders of North America, and now I’d like to dig deeper into two interesting species that reside in my home state, New York: the hellbender (Cryptobranchus alliganiensis), and the Jefferson salamander (Ambystoma jeffersonianum).

First with the hellbenders!

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Hellbender. Photo by Brian Gratwicke via Wikimedia Commons.

Hellbenders are very unique among North American salamanders in their appearance, life history, and sexual strategy. One of the few entirely aquatic salamanders in the US, this species also has no close relatives apart from the also unique giant salamanders of China and Japan (Andrias spp.). And though completely aquatic, unlike the axolotl and mudpuppies, hellbenders do not have external gills in their adult forms. They are easily identified by their large size, between 12 to 30 inches (30.5 to 76 cm) long, large, flat heads, small eyes lacking eyelids, and mottled skin ranging from yellow to gray in color. Also the fact that there is nothing else around that resembles them!

But, that is, if you can find one, as, unfortunately, hellbenders numbers have been declining over the years due to pollution, siltation and stream impoundment of the waterways they reside in. Here in New York State, they are listed as a species of special concern.

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Hellbender range. Map by Nrg800 via Wikimedia Commons.

Hellbenders range from New York to Northern Georgia and Northern Alabama, and west to Mississippi and Missouri. They favor swift moving streams with large, flat rocks that they can hide under and blend with (remember those large, flat heads – look a lot like large, flat rocks…). They also need shallow steams and rivers, and clean waters in which their prey of crayfish, mollusks, worms, small fish, and insects are abundant. Though overall population numbers are low, hellbenders have few predators, as they produce a noxious, slimy skin secretion when grabbed. Animals such as turtles, water snakes and large fish are known to prey on these animals none-the-less. The hellbender may have derived its name from the fear it seemed to have evoked in superstitious settlers with its slimy secretions and grotesque appearance, though it neither bites nor is poisonous. It has had a number of other nicknames, including ‘snot otter’, ‘mud devil’, and ‘Allegheny alligator’.

Generally nocturnal, hellbenders have been known to be active during the day during breeding season. Males make the nests, then drive a gravid female inside to fertilize her eggs. Hellbenders are one of the only species of salamanders to employ external fertilization, in which the male sprays seminal fluid onto the eggs as the female lays them. After fertilization, the female is driven away and the male guards the nest.

Tips for hellbender hunting:

Cryptobranchus_alleganiensis

Hellbender. Photo by Brian Gratwicke, via Wikimedia Commons.

1. Hellbenders are generally nocturnal, so if you are interested in seeing one, your best bet is to search at night, although it is reported that they are occasionally active during the day if the weather is overcast, or as I said, during the breeding season. Breeding seasons vary by state/latitude/temperature/elevation, so contact your local DEC, nature center, or university with a strong biology program with questions on local populations and their habitats. According to the data compiled in James W. Petranka’s book Salamanders of the United States and Canada, hellbenders inhabit and defend territories of 10-20 m², and tend to remain in restricted areas. This means that if you find a hellbender once, you may likely find it again – though if you harass it, it will probably move on, I would.

2. Your best bet in finding a hellbender is donning some fishing overalls or tall, water-proof boots and a headlamp, and exploring streams where they are reputed to reside. New York State’s population is restricted to the Allegheny region, which is a nice place to visit whether you find hellbenders or not. (You’ll find other types of salamanders and lots of wildlife there too!)

3. Once at the stream, scan the water with the light before you enter to see if you can spot any animals or movement. Then, wade in, trying to not disturb the water and bottom too much,and gently/slowly overturn large, flat rocks. If you have any luck, you may find a live specimen! You can try to catch it, but they are fast, and as I’ve said, slippery! If you do find a live animal, do not bother it for too long or you may stress it, and NEVER take live animals from the wild as pets. There may be laws that prohibit taking, as well the loss of one animal in a population with low numbers can have a serious impact, so if you do catch one, be sure to release it back where you found it. Also, be sure to gently replace rocks that you have overturned, that might actually be a hellbender’s home!

Stuffed hellbender available from World Wildlife Fund

Stuffed hellbender available from World Wildlife Fund

4.If you don’s see a live hellbender while out hunting, a good place to get a close up would be at a local zoo. I think all the zoos I’ve been to since my four-year-old was born have had live hellbenders. If you are interested in helping to protect hellbenders, the World Wildlife Fund allows you to “adopt” a hellbender, and sells these cute little stuffed ones (much cuter than in real life…), click on the photo to be re-routed. You could also ask around at your local nature center or university if they have any hellbender conservation projects and offer to volunteer your time or other resources to the projects.

Now for the Jefferson salamander!

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Jefferson salamander. Photo from Wikimedia Commons.

Another New York salamander that is common enough over it’s range and that you are likely to find if you spend a few hours or days searching (unlike the hellbender, which you might not find at all), is the Jefferson salamander (Ambystoma jeffersonianum). A mole salamander, family Ambystomatidae, these small salamanders grow to a length of 2.5 to 3.5 inches (65 to 95 mm). They are characterized by short, rounded heads, large eyes, elongated limbs and toes, and gray to brown coloring sometimes flecked with blue. Members of the family Ambystomatidae have conspicuous costal grooves, which are lines along their rib cages. Scientists use the number of costal grooves as a guide to help them identify species that are similar when genetic testing is not available, such as while in the field.

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Jefferson salamander range. Map from Wikimedia Commons.

Jefferson salamanders can be found from Southern Canada to Kentucky, Virginia, and Indiana. The species prefers upland forests that possess suitable breeding ponds, and were even collected from caves in West Virginia in 1966. In late winter and early spring, adults can be found near the breeding ponds, but reside underground in rodent cavities much of the rest of the year, hence the title ‘mole salamanders’. Juveniles are active in the autumn to early spring, depending on latitude/elevation/environmental temperatures.

Breeding male Jefferson salamanders will display a yellowish brown ridge along the top of the tail, which may be compressed. The vent, which is the hole from which the salamander expels wastes and from which the spermatophore leaves the body, will be swollen also. Adult females tend to be larger than males, a strategy often used in the fish, reptile and amphibian worlds, as the females need more bodily resources to produce eggs. The risk of being preyed upon increases with size, so evolution has tended the males toward a smaller body size.

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Pond-form larval body-type. Photo by Brian Gratwicke via photopin.com

Larval Jefferson salamanders are born from March-May, depending on latitude, and are of the pond-form body-type, with a high dorsal and tail fin, looking much like a small fish with 4 legs. Larva metamorphize into juveniles that resemble adults and reach sexual maturity after about three years.

There are few published studies on the adult morph of the Jefferson salamander. What is well documented about these salamanders though is some of their offspring, because Jefferson salamanders are well known for cross-breeding with 4 other species of mole salamanders. The blue-spotted salamander (Ambystoma laterale), the small-mouthed salamander (Ambystoma texanum), the streamside salamander (Ambystoma barbouri), and the tiger salamander (Ambystoma tirinum) will all interbreed with the Jefferson salamander.

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Blue-spotted salamander. Photo by IronChris via Wikimedia Commons.

Scientists have done many studies on the genetics and life histories of these hybrids that are considered unisexual because the offspring are generally all female. No one is entirely sure why these 5 species interbreed, but it does leave questions open about conservation issues. Of course, conservation of the parent species is important, and if most of the interbred offspring are females, one is left wondering about the fate of the Jefferson salamander species as a whole. But Mr. Petranka reminds of the importance of conservation issues surrounding the hybrids themselves, as they tend to have very restricted ranges and could be very vulnerable to extinction. Hybrids blur the comfortable lines that humans have made to define a species, and few if any laws have been made or amended to include them.

But the importance of protecting these hybrids is not lost on me, because what if this is EVOLUTION? (Evolution makes me excited!) What if this is survival of the fittest fighting in my own woods? What if it is time for the Jefferson salamander to take a back seat and let a a new species emerge? Should we, as humans, impede that? Should we encourage it? Unfortunantly, it is never cut and dry, since humans have made their impact over much of the entire earth. Our direct and indirect affairs affect selection, and add additional pressures on certain populations in ways such that we can’t know if they would be selected for or against. These are questions biologists and law makers must face every day. (FYI: Jefferson salamanders are not listed as a species of special concern by the Fish and Wildlife Service, this rhetorical question was just my brain asking rhetorical questions.)

Fortunantly, I am currently a stay-at-home-mom and get to worry about my kids learning to care for the earth more than writing up conservation laws to protect it, and perhaps you are too, so, let’s delve into the fun part of maybe seeing one?…

Tips for hunting for Jefferson salamanders:

1. Follow the steps outlined in my previous post, Herp Hunting: Part 1 – Diverse Salamanders, and go hunting in the woods. Spring-time is your best bet for finding animals in the leaf litter, but you are welcome to try at any time of the year. Remember to replace any leaf litter, rotted logs, or overturned rocks to their original position because that rock may be somebody’s home.

2. If you find a live animal, keep your hands moist when handling it, and make sure they are clean of any sunblock, bug spray, or other chemicals.

3. NEVER take wild animals from their habitats. There may be laws prohibiting taking, resulting in steep fines or jail time of broken. Also, without DNA testing, it is impossible to know if the salamander you found is a hybrid, so avoiding taking animals will assist in not depleting vulnerable hybrid populations.

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Jefferson salamander. Photo by Dave Huth via photopin.com.

4. If you are looking for more information on populations in your area, contact your local DEC, nature center, or university. If there are no programs in your area centered around salamanders, inquire about participating in university research, taking a herpetology course, or organizing an event at your nature center.

Happy herp hunting and the best of luck to you in finding some of these amazing creatures! Stay tuned as well, coming next I will be highlighting the Red-spotted Newt, and the Red-backed salamander.

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Click on photos to be redirected to Wikimedia Commons or photographer’s Flickr page for more information and Creative Commons licenses.

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