17 October 2011

Still Time To See Sallies

When I received my most recent volume of Proceedings of the Indiana Academy of Science, I found myself looking at a Four-toed Salamander (Hemidactylium scutatum) on the front cover, and immediately thought of my searches for this species earlier this year (click here and here) with Lee Casebere, Scott Holaday, and Bill Ringer.  Upon looking at the first article, I was excited to read about the surveys for Four-toed Salamanders that Lee had done with Michael Lodato in Indiana during the past several years [Casebere, L.A. and M. Lodato. 2010. The Four-Toed Salamander (Hemidactylium scutatum) in Indiana: Past and Present. Proceedings of the Indiana Academy of Science. Vol. 119 (2)].  After reading the article, I emailed Lee to let him know how much I enjoyed the article and that I hoped we could look for Four-toed Salamanders again soon because I needed to get some new photos of them (since the only time I'd ever seen one previously was several years ago in Michigan).  It didn't take long for Lee to write back and thank me for my compliment, and soon enough we had plans to go look for salamanders at Koontz Lake Nature Preserve on 15 October.

Our target, a Four-toed Salamander

It didn't take long to find our first Four-toed Salamander. Although this species was listed as endangered in Indiana until very recently, it was still a treat to find several of them on this blustery autumn day.

A white belly with dark spots gives away the identity of a Four-toed Salamander

The telltale identification feature of Indiana's smallest salamander is the polka-dotted ventral side, with dark spots on a white belly.  Other good identification features are the scaly back (this species was once known as the Scaly Salamander), the dryer texture, and the constriction at the base of the tail (where the body and tail meet).  Oh yeah, and they have four toes on their hind feet.  Males and females look similar, but the males have blunt snouts, whereas those of the females are rounded.

At up to 3 inches long at the most, Four-toed Salamanders are Indiana's smallest salamander species

The geographical range of the Four-toed Salamander includes much of the eastern half of the United States and into Canada to Nova Scotia, with a more concentrated distribution in the northeastern U.S., along the coastal plain, and around the Great Lakes.  Disjunct populations occur in the Ozarks, in the Florida panhandle, and in eastern Louisiana.  In Indiana, Four-toeds are found in sphagnum and tamarack bogs, near woodland springs, in swamps, and in forests with vernal pools.  Sedge clumps or mosses seem to be essential, as the species uses these microhabitat features for nesting sites.

Note the scaly skin and the constriction at the base of the tale in the Four-toed Salamander

Although Four-toed Salamanders were our target for the day, we had good luck with other species as well.  Blue-spotted Salamanders (Ambystoma laterale) were abundant.  Although they can be impossible to distinguish from triploids and hybrids of the Ambysoma jeffersonianum complex without genetic analysis, Lee felt pretty confident that the individuals we were seeing were most likely true Blue-spotted Salamanders, which seem to be confined in Indiana to the northern quarter of the state.

The coloration of this handsome Blue-spotted Salamander reminds me of one of the poison dart frogs in the rainforest

Slightly larger and definitely stockier than the Four-toed Salamander, Blue-spotted Salamanders rarely exceed five inches in length.  The species is known from the eastern provinces of Canada, from the New England states, and from around the Great Lakes.  In Indiana, they are often found in moist, sandy woods.

The third species that we saw was the one that we most expected to see, Redback Salamander (Plethodon cinereus).  There are two common color morphs of this species: one with dark sides and a wide red to orange midline stripe (the striped morph), and one uniformly dark above (the unstriped morph).  A third color morph (the red morph) is uncommon in Indiana and only found in southeastern Indiana; it is uniformly red to orange above.

Probably the brightest and largest Redback Salamander (striped morph) that I've ever seen

For more information on the habits, habitat, and range of the Redback Salamander, see my earlier post that includes information on this species.

The unstriped morph (leadback) Redback Salamander (above) can be confused with the Ravine Salamander (Plethodon richmondi), which is restricted in Indiana to the southeastern part of the state

Lee told me that this was one of the best days he has ever had in terms of number of salamander individuals observed; it was certainly my best ever salamander day as well.  In our three-and-a-half hours together in the field, we tallied 7 Four-toed Salamanders, 20 Blue-spotted Salamanders, and 31 Redback Salamanders (16 striped morph and 15 unstriped morph).  After Lee left, I spent another half hour and found an additional 4 Blue-spotted Salamanders and 1 unstriped morph Redback Salamander.  There probably aren't many days left this year when the sallies will be active, so get out there soon if you plan to find them before the snow falls!

3 comments:

A.L. Gibson said...

Cool post, Scott! Coincidentally I found a number of redbacks on my hike today and I rooted through some overturned logs. The unstriped morph we call the "leadback" in my neck of the woods; and I couldn't agree more about the one you pictured being so colorful and big!

Janet Creamer said...

Great post, Scott! Sounds like a wonderful day out in the field.

Scott Namestnik said...

Thanks Andrew and Janet. We were calling the unstriped morph "leadback" in the field, too. Yes, Janet, it was a wonderful day in the field. Any day in the field with someone of Lee's caliber is a wonderful day!