Tuesday, March 22, 2011

Michigan Season is Underway!

This past weekend, we finally got some rain in southeast Michigan and it got some stuff moving. I spent some time aiding a study that is ongoing to the genetics of the Smallmouth Salamander in Michigan. This species reaches its northern range limit in extreme southeast Michigan. This area is the population center of the state and is extremely developed. Though Smallmouth Salamanders were probably never extremely common in Michigan, fragmented habitat has caused a decline in their numbers and they can now only be found in 2 or 3 locations and are listed as a state Endangered species. The point of this study is to take tail clips for genetic analysis to understand the genetic health of the few Michigan populations and to monitor breeding activity. We managed to trap and process over 100 animals over the course of two nights and also had some other species show up as well. All of these specimens were found at the same breeding site.

 Smallmouth Salamander - Ambystoma texanum

Unisexual Hybrid Salamander - Ambystoma sp.

Unisexual hybrids can be diploid, triploid, or even tetraploid. These animals share the genotypes of the Blue-Spotted, Jefferson's, Smallmouth, and occasionally Eastern Tiger Salamander. These unisexually female salamanders migrate to breeding pools with other salamanders on warm, rainy spring nights where they utilize sperm from males of other Ambystoma species to fertilize their eggs. The sperm of the males stimulates unreduced eggs to develop, resulting in clones of the female, this is similar to a process known as gynogenesis. It is also possible for the genome to be replaced or for the number of chromosomes in the offspring to be increased. The genetics of these salamanders is still undergoing study by many researchers. Here's a few other animals that showed up this past weekend.

Spotted Salamander - Ambystoma maculatum

Eastern Tiger Salamander - Ambystoma tigrinum

That's all for now. Until then, happy herping!


  1. Nice post! Is it common for maculatum in Michigan to have darker, almost orange spots, on the head? It's a southern trait but I guess I've never noticed it on photos from the northern midwest

  2. At least in southern Michigan, a lot of the individuals I've seen do have that trait. Not so much in the northern part of the lower Peninsula though.

  3. 4-5 years ago I found a smallmouth salamander while
    scouting the property I deer hunt. It was in Concord,mi. I'm 100% sure that it was a smallmouth salamander.

  4. We just found a small mouth on the apron of our driveway tonight. I have him in a bug catcher to show the kids on the morning before letting him go. We're in Lapeer.