Outdoors North: Spring brings own palette of sounds to U.P.

“Frog went a-courtin’ and he did ride, with a sword and a pistol by his side, uh-huh.” — Traditional

With the springtime comes the familiar sounds of migrating birds, winging back north to set up early nesting territories, sometimes with the frost and snow still on the ground. Perhaps most familiar among these, beyond the honking Canada geese, is the robin, who sings a cheery song, even when it’s raining.

There are resident bird species familiar among the sounds of spring too. A favorite, tried-and-true, is the male ruffed grouse, whose spring mating ritual consists of the accelerating drumming sound he makes with his wings, while standing on a mossy log downed on the forest floor.

But then there are other sounds, less distinct, often harder to pick out or identity from among the sounds of birds, but once found in the air by the ears, they are mesmerizing to listen to.

In some ways, finding these sounds, is like staring at one of those picture-in-a-picture images where you gaze deeply until suddenly a previously invisible image will jump out of the picture to your eyes.

Relocating the image once you’ve seen it is a lot easier the second time. The same is true with these sounds of nature — some low, some high, some in between — once you pick them out of the air, they are always with you.

These sounds are the songs of one toad and a handful of frogs found in this part of Michigan. For some of these species, their calling calendar, which equates to their breeding period, begins this month, anytime now.

As temperatures rise, frogs move from their winter hiding places in the mud or at the bottom of ponds to breeding locations. Water and air temperature and humidity all play a part in triggering this activity.

They begin to sing in order, like the creatures introduced one-by-one in the old children’s folk song, “Froggie Went a Courtin.'”

Often, in the Upper Peninsula, the first frogs heard in springtime are the wood frogs, which can begin breeding activities even before the ice has melted completely from the wooded swamps and ponds they inhabit.

Wood frogs sound like ducks quacking or people chuckling. They breed from about the first part of April to the middle of May.

Western chorus frogs — whose raspy trill rises as though someone were drawing a finger across the teeth of a comb, are found in wet meadows, woodlands and marshes — are rarely seen after the breeding season. The calls of this frog can be heard from the first part of April into mid-May.

However, these frogs are relatively rare in this part of Michigan. Boreal chorus frogs, which are similar, are rarer still for the U.P., only occurring on Isle Royale.

Next to come in is the spring peeper, a small frog with a dark “X” marked across its back. The ringing sound of these frogs, somewhat like an echo, which many people often mistake for birds, can be almost deafening when thousands of male frogs are singing at once on a spring night.

Approach the edge of a tiny pond though, and they may suddenly go quiet.

Spring peepers have the longest calling calendar of the U.P. frogs, starting at the beginning of April and continuing to around the first of July. They are common.

Mid-April begins the calling of the northern leopard frog, which is a low, croaking kind of snoring call. They sing from now until around the first of June. This is a familiar frog of the meadows and once was the most common frog species in the state.

For reasons unclear, a population decline of this species has resulted in it now being considered rare in some parts of Michigan. Pickerel frogs also make a snore-like song, but they are very rarely found in the U.P.

Next to come in is the region’s only toad species, common in gardens and woodlands — the eastern American toad. These toads sing from around the first of May to the end of June, their song a long, extended trill.

At one time, secretions from the skin of these toads were thought to give humans warts, to match the skin texture of the toads themselves. While that isn’t true, the distasteful secretions do serve as a defense mechanism, warding off predators that might pick up the toads in their mouths.

As the nights get warmer, and June arrives, eastern gray and Cope’s gray treefrogs can be heard delivering their strange trilling songs. On warm, rainy nights, these frogs are out calling and may be found sticking themselves to windows or walls of buildings with their specially-adapted feet.

These frogs are found in backyards, swampland and woods.

Next to come in, of these late season singers, is the green frog, which can be heard in this region from late May into mid-July. Their songs sound like a rubber band, or banjo, being plucked. This is a larger, toad-sized frog that is found in ponds, swamps and along lakes and streambanks.

Mink frogs and bullfrogs round out the U.P. frogs. Mink frogs are usually found close to a permanent water source. They are found throughout the region, but are generally uncommon.

Their song is often described as a distant hammering sound. They are at home along pond edges and in bogs. Bullfrogs are rare across much of the state. They are comparatively very large frogs, reaching 8 inches in length. Their legs are considered a delicacy by many humans.

Like mink frogs, these frogs sing from around the first of June into early July. Bullfrogs have a low croaking like a foghorn, many have likened to the frog saying “jug-o-rum.”

To listen to these frogs and learn to recognize them when you get Outdoors, visit this helpful online listening guide:

Michigan Frog and Toad Survey Audio Training Files

Editor’s note: Outdoors North is a weekly column produced by the Michigan Department of Natural Resources on a wide range of topics important to those who enjoy and appreciate Michigan’s world-class natural resources of the Upper Peninsula.