Backyard Biology

Nature stories from my backyard and beyond

Nature Stories

Spring Peeper

Thursday, March 8, 2012

The year was 1997.  Spring had been with us for some time.  The frogs were singing their love calls.  The red-wing blackbirds were staking their territories.  Trees were beginning to bud out.  Then, like a practical joke, on April 1st., twenty-two inches of snow.  The biggest snow storm of the year.  A not-so-subtle reminder by Mother Nature to take nothing for granted.

The storm affected every aspect of spring.  Trees snapped under the weight of the wet snow.  Birds ceased their spring songs as they huddled under cover.  Even we were humbled by the storm.  We had lost power and did our own bit of huddling under the blankets.  The storm humbled every living creature that day - except for the peepers.  Two weeks earlier, they had started singing their love calls and they weren’t about to let  two feet of snow  dampen their ardour.  By four in the afternoon, when the snow had stopped and the temperature in the high thirties, they were once again singing their love song.


I do most of my frog watching in the detention basin behind my house.   It is home to a half dozen species of frogs and toads.  Some only use it for breeding while others are residents throughout the season.  The first to arrive in the spring are the spring peepers and the wood frogs.  At one to one and a half inches in length, the peepers are also the smallest.

That year, the first peepers arrived at the basin on March 3.  The temperature was in the mid thirties.  Unlike most other frogs, peepers can withstand being partially frozen.  In the cold weather, their body fluids contain ethanol, a frog anit-freeze.  This allows them to survive a sudden cold snap and to continue with their breeding when the temperature rises above freezing.


While the peeper is a tiny frog, there is nothing small about its voice.  The love song is a sharp piercing single note whistle, rising in inflection.  The song carries for hundreds of yards through the woods.  Sitting in the basin, listening to thousands of them calling can be quite deafening!  It is truly hard to believe that such a loud sound can be produced by such a small animal.  It is also amazing that this sharp piercing sound can incite passion in any living creature.

Each male peeper has his own small territory.  When another male enters his territory, he gives a trilling call, telling the intruder to vacate the premises.  These are the only two calls I have heard the peeper make.  However, using my imagination, I can translate this frog language into a quite interesting frog dialog, wooing the females while daring other males to cross the line at their own peril.peepers mating


The females lay about 800 eggs.  The eggs are laid singly to submerged vegetation.  After mating, the females leave the breeding pools while the males return and set up their territory once again.  The eggs take about a week to hatch and spend a month and a half as tadpoles.  The development of the peepers is rather brief.  This allows them to breed in temporary pools that may dry up in the summer.  These temporary pools don’t have a fish population, a big predator of tadpoles.


While many people have heard spring peepers, very few people get to see them.  Standing in a pool of water with peepers singing all around and not one in sight can be a frustrating experience.  What is needed is to get down on your hands and knees and get a frogs eye view.  This is a technique that only the most ardent frog watcher will employ on a cold March evening.  Needless to say, I have very rarely seen peepers.  However, that year my luck was about to change!


One evening, while walking past the basin, I noticed peepers singing on both sides of me.  That could only mean that peepers were singing out of the cold water.  I could safely pursue them on my hands and knees. 

As with all peepers, they stop singing when you get close.  But knowing the ardent nature of the beast helps.  If you are quiet, they will begin singing again in a relatively short time.  And sure enough, one started singing about two feet in front of me.  On all fours, I moved two feet forward, right over him.  Of course, he stopped singing as I began to move.  But I knew I only had to remain still until his urges overtook his caution.  Sure enough, in a matter of minutes he began to sing again.  But somehow he was two feet ahead of me again.  Again I crawled forward and again he starterd singing two feet ahead of me.  This went on a few times until I decided to employ the much larger brain that nature had endowed humans with.  I would outwit the frog.

I realized that the call is deceptive as to distance, but not to direction.  Laying down on the ground, I shone my flashlight along the path the song seemed to be coming from, inspecting every few feet for my frog.  Eventually, I spotted him about six feet in front of me.  He was not on the ground as I had expected, but about a foot up on a small shrub.  I had forgot that peepers are a type of tree frog with tiny suction pads on their feet.  While they are most often found on the ground, they are very capable climbers.


As I was stalking the peeper, a few questions occured to me.  Why were these peepers singing away from the breeding pools.  And if one attracted a mate, where would she lay her eggs?  It may be that these are young males, not quite confident of their prowess to secure a good territory and yet still feel the need to sing.  Or perhaps they announce their arrival at the pools by song.


There is one time in the peepers life that they are easy to find.  In fact, too easy.  When the tadpoles emerge as frogs and leave the pools, they can be seen crossing the trails by the thousands.  The trail is literally alive with peepers!  But soon they have finished their migration back to the woods, not to be seen, or rather heard, until love brings them forth early next spring.