As luck would have it, I was able to secure a little bit of field time in mid-month. And by little, I mean two very brief stints in between errands. I was able to conjure up two blue-spotted salamanders (Ambystoma laterale), one on each walk (November 8 and 15). And since I cannot ever talk about blue-spotted salamanders too much, I'd like to expound a bit on this amazing little amphibian.
First off, these guys are extremely cold-hearty. Very often, a salamander, black with blue spots throughout, is the first herptile to be found in the spring (as was the case this year). Other local herps are early risers - chorus frogs, spring peepers, etc. But in my time, I've found that the zealous blue-spotted salamander has them beat by as much as several weeks. I have flipped logs in early March - logs that were fused to the ground by frost - and found blue-spotteds, chilled to the bone and lethargic, but invested in waiting for the first heavy spring rains to lull them away from their decomposing abodes. In the fall, they again can be found underneath logs, milking every last tolerable day. As most or all of their kin are settled in deep underground, ready to turn off for the brutal cold season, the hearty blue-spotted wouldn't think twice about snatching an equally cold-tolerant centipede foolish enough to scamper by.
But it's not just cold weather the blue-spotted salamander is adapted to. More than any other ambystomid in the area (in my studies), the blue-spotted salamander is easily procured during the summer months as well. Tiger salamanders (Ambystoma tigrinum) can also easily be found during the warm months, whereas spotted salamanders (Ambystoma maculatum) generally avoid heat and dry weather and will disappear into the nether regions of the woodlands they live in once conditions become unfavorable. I have found blue-spotted salamanders in almost every month of the year, even in July and August, where Chicago weather can peak at or above 100 degrees. As temperatures approach 80s or higher, the blue-spotted salamanders will often burrow down under leaves or logs, but can still be found under really big logs that are able to maintain a reasonably-cool microclimate.
The heartiness of the blue spotted salamander intrigues me but does not surprise me. This species' southern terminus appears to be the Great Lakes region (things get kind of confusing and long-winded south of here; the Tremblay's salamander (Ambystoma tremblayi), Silvery salamander (Ambystoma platineum), and Jefferson's salamander (Ambystoma jeffersonianum) replace it in a crazy soap opera kind of way - trust me, it's worth its own post). As this animal extends far North as northern Quebec and Newfoundland, it has to contend with even colder and longer-lasting winters. The ones here have it easy, so to speak.
Here is a vernal pool in extreme northern Cook County that supports a cacophonous population of Western chorus frogs (Pseudacris triseriata) during the early spring. It is difficult to access any time of the year due to invasive thorny plants that grow all around its perimeter. You can see that the water is frozen by this time of year already. I focused on looking for blue-spotted salamanders in the vicinity of this pool.
A bend of the Middle Fork of the North Branch of the Chicago River, sporting surface ice.
And sure enough, there's a blue-spotted salamander. Found under a log surrounded by patches of ice and snow, this salamander was joined by an array of invertebrates - numerous woodlice, a big hornet that was alive but barely twitched, beetles, earthworms, and slugs. Some of these animals can be seen in the photo. Note - the temperature was in the upper 20s Farenheit.
Details of a beautiful paper wasp nest also found nearby.
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