I live on one of those quiet country roads that feels like it’s off in the middle of nowhere. To the east of my house there is a stop sign at a 4-way intersection of similarly quiet country roads, one of which is a dead end. To the west there is another stop sign at a T-intersection with a slightly more traveled road. So I live in a situation in which the only traffic on my road is really made up of the relatively few people that live on the road.

Modern life is noisy and the hum of activity can be ever present. On certain days I can hear the very distant rumble of large trucks carrying freight from one place to another. Most days bring the sounds of commercial airliners, military planes and helicopters of various types. It is not uncommon to hear distant gunshots from people who are practicing their aim, the squarl of chainsaws and (of course) the drone of mowers. And when the weather gets warm you can often hear the poorly-muffled motorcycles from miles away. But on some days and on most nights you hear nothing at all. At least no human-made sounds.

It is just such a set of circumstances that I find myself in as I write this column. I woke at 2:30 a.m., put a pot of coffee on and stepped out onto my deck. What initially greeted me was pure and delicious silence. Not even the cottonwood tree was murmuring to me because the air was so still. To the east, south and west, I saw nothing but stars twinkling in a cloudless sky and I could easily have remained there in a lounge chair until I dozed off, but I was quietly reminded that there is a pond to my west when I heard the sonorous drone of a bullfrog that came drifting across the meadow.

Of the frogs that live in our area, the bullfrog (Lithobatescatesbeianus) is probably the most aquatic. It is also the largest, with a good-sized adult attaining the size of a large baked potato. Of all of our local frogs it would also be the one that is the “greenest” in color, which is odd when you consider that the next-largest species is actually called a green frog (L. clamitans). The thing to remember is that these frogs can actually change the color of their skin to help with thermoregulation. On cold days, the frogs can turn brown, but on warm days they shift to a bright yellow-green.

Bullfrogs are denizens of permanent water and are thus only found in great numbers in lakes and ponds. Males set up a territory and do their best to attract females with their songs, which someone initially compared to the bellowing of a bull (hence the common name “bullfrog). Females are then attracted to the songs they find the most appealing and a brief period of mating and egg laying follows. This is a procedure known as “amplexus” and it requires that the male grasp the female around the waist so that he can fertilize the eggs as they are laid.

The reproductive capacity of bullfrogs is somewhat astonishing. Males set up a territory and wait for interested females to approach them. Females generally have only one opportunity to reproduce in a given summer, so they can be quite fussy about which male they select. Once a choice is made, the female will initiate proceedings. This is generally done in shallow water and a large female can release… wait for it… up to 12,000 eggs. A male that attracts several females in a summer could potentially father a quarter of a million offspring!

But reproduction at this scale points to an extremely high mortality rate. The eggs are good food and any young that hatch are also good food. The size of a bullfrog requires that they remain in the juvenile “tadpole” phase for 3 years before they finally make the transition from what looks like a golf ball with a tail into an adult, 4-legged frog. During all of this time the young frogs are good food for all sorts of animals and I am reminded of this every time I see a heron gliding over the meadow as it makes its way toward that pond.

One last bit about bullfrogs you need to know is that they are notoriously skittish. If I were so delicious and in such high demand I would probably be a little skittish myself. If, however, you should happen to find yourself looking at a large, green frog and you want to identify it, there is one thing that you need to look for. Starting just behind the eye there will be a raised line of skin that reminds me of the seam decorations that used to come on the seats of cars in the 1970s. In a bullfrog this line of skin will stretch as far as the eardrum (the “tympanum”) and it will then follow the curve of the eardrum down toward the shoulder. In green frogs, this line of skin will continue in a straight line down toward the hips.

So, if you are lucky enough to have a pond nearby, or if you are lucky enough to know where a pond that you can visit is located, why not plan a trip to see if you can hear and possibly even see a bullfrog this summer. Also, be very mindful about rainy nights in August because it is on warm, rainy summer nights that frogs will go on walkabouts and disperse across the landscape. We don’t want to hit them with our cars just as they are going on their first adventures.

Bill Danielson has been a professional writer and nature photographer for 26 years. He has worked for the National Park Service, the US Forest Service, the Nature Conservancy and the Massachusetts State Parks and he currently teaches high school biology and physics. For more in formation visit his website at www.speakingofnature.com, or head over to Speaking of Nature on Facebook.

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