Saturday, March 22, 2014

First amphibians of the year

A Western Chorus Frog, Pseudacris triseriata, sits in a wet pool, the upper half of his body above the water.

I should qualify the title of this post: First amphibians of the year (FOR ME)! This has been a brutal and prolonged winter, and even now, in mid-March, the frosty old man is reluctant to take back the snow and ice. Here in central Ohio, we've scarcely had any of the decently warm (50 F or above) rainy nights that amphibian-seekers pine for. It seems that the majority of frogs and salamanders have yet to make the vernal pilgrimage to the breeding pools, and individuals are just trickling in bit by bit - no massive migrations of yet.

Last night was one of the few warm evenings we've had, but it wasn't wet. Dryness inhibits major movements of amphibians; they much prefer to move towards breeding haunts when everything is nice and soaked. Nonetheless, I knew that at least some Spring Peepers and Western Chorus Frogs would be in the wetlands, and I really wanted crisp images of the latter for an upcoming column. So, I headed to one of my favorite amphibian routes near Bellefontaine last night, stopping first to pick up Bellefontainite and amphibian enthusiast Cheryl Erwin.

Sure enough, the peepers and chorus frogs were in good tune, but not in the numbers they soon will be. Just smatterings of individuals calling from wetlands where there should soon be many more, if the weather ever warms. This Western Chorus Frog is the same individual as in the first photo, just seen from another angle and while he was singing. The animal was issuing his guttural creaking trill regularly, counter-singing with another frog about fifteen feet away.

Getting images of singing chorus frogs can often be a challenge. They seem to prefer staying towards the interior of their wetlands, and that means out in the deeper water. To capture this animal on pixels, I waded into water that soon threatened to overtop my knee boots. After spotting the animal from about fifteen feet, I slowly crept up while he sang. Then came the cold, wet part. I dropped to my knees to get down closer to my subject's level, and leaned in close. Getting, of course, soaked in the process and filling the boots. Someday I'll resort to hip or chest waders, but somehow getting as wet as my subjects makes me feel more a part of the whole scene.

A giant Eastern Tiger Salamander, Ambystoma tigrinum, lumbers from the wet grassy verge of a large seasonally inundated wetland. We were quite pleased to find a few of these jumbos around one of their breeding haunts, but I don't think the majority have yet arrived. Tiger Salamanders prefer open grassy wetlands - not the wooded vernal pools of most of their Ambystomid brethren.

The vernal emergence and migration of salamanders will never cease to amaze me, and I get out as much as possible to look for them. There are usually only a few good nights when temperature and moisture are conducive to mass movements, and I'll hope to catch a better night within a week or two.

Fortunately, my favorite Tiger Salamander breeding site is along a road that floods out completely in a few spots, and has few houses along it. Thus, the vehicular traffic is almost nonexistent. Getting pancaked by cars is a real threat to these animals as they attempt to move overland to the wetlands. When development brings too many roads and too much traffic, the salamander populations are likely to eventually disappear.


TheDon said...

I'm trying to see the salamander migration at a vernal pool and wonder if you have tips for seeing it. I'm thinking I should look for forecasts of rain at night, with warm temperatures.

But I don't know if that means 40 degrees or 50 degrees F minimum?

Also, does night mean anytime from sunset to sunrise or just midnight to sunrise?

I'm trying to narrow it down so I know when to go to the vernal pool.

Do I stay up late on the night with a good forecast and only go to the pool once it starts raining?

Do I try to stay there all night until daybreak? Or do I just spend two hours there?


Jim McCormac said...

Above 50 degrees is best, although the animals will move in smaller numbers in the 40's. It doesn't matter if it is actually raining, just that it has recently and the ground is wet. This often means being out in the rain, though. Usually amphibians are moving by 9 pm if conditions are right, and may continue all night if conditions remain warm and wet enough.

TheDon said...

Thanks! That makes it seem possible to view and gives me the guidelines I need and have sought for years!!


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