Frog Sex Party
Reptiles and amphibians have always been favorite animals of mine. I grew tromping through wetlands catching turtles, frogs, salamanders, skinks, and every other kind of critter that would fit in a one-gallon ice cream bucket. One of my fondest memories was my dad challenging me to “Go find out” what was making the noise from a small vernal pool not far from my house. I was 11 or 12 years old and I spent all day finding out. What he sent me to find was one of the smallest, yet loudest, frogs native to Minnesota the Western Chorus Frog. These tiny frogs are about the size of the end of my finger and will stop calling with the slightest of movement. I can remember spending hours stalking a single calling male in that pond for an hour only to have it slip under the surface and disappear as I went to catch it. My adventure in that pond was not in vain however, 6 hours and a sun-burned neck later I triumphantly returned home with a bucket “full” of 13 Chorus Frogs. My dad did not believe that I was able to catch one let alone 13!
Today I live on a small vernal pool not far from where I grew up. Like the vernal pool of my childhood this new pool is a breeding pool for many species of frog. There are 5 species of frog and one species of toad that call just feet from my backdoor. Chorus Frogs are often the first species to call after the ice goes out. This spring the first male began slowly calling from a 10ft by 10ft opening in the ice on the pond. This drive to call is not simply linked to the weather it is driven by testosterone.
NOTE: Check out the small ripples created by the vibration from the frog’s call. This is how I was able to locate the frogs when I first caught them as a child.
To me a pool of calling frogs is not just a calming and relaxing sound it is trip far back in time. I imagine those ancient vernal pools millions of year ago filled with amphibians calling for a mate. Frogs have been calling for mate in these pools for millions of year, and hopefully more millions more.
During my undergraduate education I had the pleasure of working in a frog behavior lab at the University of Minnesota. The lab is studying the selectivity and sensitivity of the amphibian ear. Male frogs call to attract a mate, how does the female select a worthy male in a pond filled with hundreds or thousands of testosterone filled males calling non-stop? It is not unusual to see dead frog floating in breeding pools as the male frogs will literally call themselves to death, with the drive to reproduce.
To get these pictures is no easy task. Remember these frogs often stop calling when I simply walk into my backyard. All of these photo were taken just inches away from the frog as it was still calling. To get that close took nearly a half hour of stalking in near freezing water on my hands and knees. It was worth the effort to capture pictures of the amazing little frogs.
I added the last two photos to illustrate just how well these frogs are camouflaged in their environment and to give a relative size of what I was looking for. I am looking forward to a productive year for ‘my’ frogs. I can hardly wait for the Gray Tree-frogs to begin their breeding frenzy. As the different species begin calling I will try to capture pictures of the each event!
Up Next: Fallen Angel