May 29th, 2016 permalink
Life is confusing. “Male Bullfrogs” sounds redundant, but there’s no such thing as Cowfrogs. They are female bullfrogs even though there are no female bulls in mammalian circles. That is unless some bulls are doing that Hollywood thing to get their own reality television series.
Male bullfrogs are advertising their suitability as mates now to the females by mooing at the millpond. Mere moos might not be enough. The girls must evaluate the robust nature of the moos since the boys place their throats in the water to the moos sound larger and travel farther. You can see the vibrations this gentlefrog’s moos generate (below).
Sadly, this bullfrog cannot participate in this year’s Fringo! game. I couldn’t get a view of him from the officially sanctioned right front three-quarter view. Maybe I’ll meet him on the sidewalk on some humid night in the weeks to come to snap his portrait from the prescribed angle.
June 4th, 2015 permalink
Since almost everyone carrying a cell phone with a camera, at least one lucky millpond park visitor will win a free bag of duck chow playing Fringo! this summer!
Here’s the deal: I photograph every frog I find in the park and post them on this page. If you find and photograph the same amphibian and send me the picture, you will be handsomely rewarded. Here’s one of the two frogs I’ve seen this year. He’s a beaut, a healthy bullfrog at least 6″ from nose to tail seen near Stillwater Grill. Keep your eyes open, maybe he’ll pose for you, too.
May 20th, 2015 permalink
Rainy evenings are the best time to find Bullfrogs like this beauty who are “working” under a parking lot light. Frogs have a job to do even though they might only view it as filling their bellies. They significantly reduce the insect population. We should all thank them for it especially once mosquito season arrives. Unfortunately, they are also capable of taking a toll on ducklings during the first days of their lives. The frog motto is, “If it fits in my mouth, I’ll do my best to swallow it.”
This Bullfrog ought to be called a cowfrog because it’s a female. You can tell because its tympani (think: ear) is smaller than its eye. Males’ are usually larger than the eyes. Bullfrogs look similar to Green Frogs but lack the ridge of skin that runs from above the tympani to the hips.
This frog is not a contender for this year’s Fringo game. It was found outside of the millpond park. The game will start as soon as I post the first frog on this page.
June 27th, 2014 permalink
What better way to spend a warm summer evening than submerged in the warm water surrounded by tiny duckweed plants waiting for the love of your life to answer your romantic cloakings? Bullfrogs have a cushy life except for the constant threat of being nabbed by a predator and spending their winters burying in pond mud for six months.
May 30th, 2014 permalink
Thanks to the quick hands of a pond regular, Steve, I had the chance to photograph this sizable bullfrog who wasn’t particularly thrilled with her opportunity for worldwide Internet fame as a model. She could rightfully be called a cowfrog or a heiferfrog since her tympana indicate it’s female. The women’s movement has failed the amphibian sector in their demands.
In addition to being a new entry into Fringo, she reluctantly agreed to help me explain how frogs are capable of retracting their eyes into their skulls so they are more streamlined when they swim.
In their resting state, frogs eyes are fully extended (top 3 photos). They can’t rotate them like humans; they have to turn their whole body if they want to alter their view. They rarely need to do that, however, since they have almost a 360 degree view of their surroundings as shown from the tail end view (bottom).
While they don’t have exceptional vision toward the rear, they can at least see movement if a predator would be approaching them. That gives them enough time to foil an attack by leaping forward.
When it’s time for my model to leave with a mighty shove of her strong legs, she demonstrates how she pulls in her eyes to reduce the drag protrusions would be in the water (left). She didn’t explain how she does it.
The bullfrogs are very actively pursuing partners at the millpond now. It takes bullfrogs 3-5 years to reach maturity once they magically transform from their tadpole beginnings.
Males have three strategies to guarantee their genes are passed on to the next generation of calves. (Tadpoles, actually. I’m just going with the bovine motif here.) This female, if she’s mature will lay 1,000 to 20,000 eggs when her time comes … if it hasn’t already. (I don’t know the timetable in Brighton.) She’s quite thin so maybe she’s already delivered the goods, but then again, she’s a model. Maybe she survives on whiffs of food like her human counterparts.
May 27th, 2014 permalink
The water’s warmer and so’s the air. As a result, the bullfrogs have staked claims in the millpond and spend their evenings letting their rivals and potential sweethearts know where they are. This one is large enough to fill the 12″ diameter lily pad. If you view the larger image, you can see the ripples caused by his croaks.
September 5th, 2012 permalink
By the time I return home from the millpond after an evening of photographing wildlife and communing with noisy and demanding ducks, I’m ready to relax. But when a young bullfrog greets me on my porch, I’ll take off the backpack and have another go at photography.
See, we’re both opportunists.
I’ve got to be ready to shoot when Nature presents me with opportunities. This small bullfrog (3″ nose to tail) came to my porch after dark to wait for moths and other insects to drop from the porch light. We made a deal: I’d photograph him for a few minutes and then let him continue pursuing the satisfaction of his appetite. It was win-win.
August 9th, 2012 permalink
Regular visitors to Brighton’s millpond park can go the whole summer without seeing an American bullfrog even though they can reach 8″ long and it sounds like a cattle ranch once it gets dark. During daylight, the amphibians might spend their entire day submerged in the duckweed so only their eyes and nostrils are visible. Unless they make a quick movement or you make a concerted effort to find them, they are well camouflaged. Their coloration mirrors the plants and water they live in.
If you walk the trail at night when it’s raining, your chances of seeing them is much better. They leave the pond to hunt insects, worms, and all things that move through the wet leaves and grass. They reign as the top predator for all things they can stuff in their big mouths including baby birds, tiny turtles, small rodents, and the usual array of insects and worms found near ponds.
This chap is a male. You can tell the gender by the size of their external eardrums (tympana). If it’s larger than the eye, it’s a male. Green Frogs are sometimes difficult to distinguish from young bullfrogs. They have a fold of skin from their tympana to their hip that bullfrogs lack. Adult green frogs never reach the size of adult bullfrogs either.
June 23rd, 2012 permalink
Michigan bullfrogs have evolved to be the same color as the floating duckweed, water lily pads and the soil along the edge of the ponds. In fact, even their bright yellow throats mimic the color of the bullhead lilies around them in daylight as shown in these previously published blog photos:
Their cryptic coloration protects them from predators and also conceals them from treats on the bullfrog menu like smaller frogs, insects, and even newborn ducklings they might gobble in one quick gulp. On warm nights at the millpond, legions of these 6″ (nose-to-tail) amphibians “moo” so loudly that you’d swear you were down on the farm. Because its tympanic membrane is about the same size as its eye, this bullfrog (top and bottom photos) is actually a cowfrog but there’s no such a name in the frog world. Males’ membranes are usually larger than the eyes and their throats are often brighter yellow like the photo directly above.
At night, they are easy to hear but difficult to see until the flash from my camera reflects bright rainbows in their eyes. That’s caused by the refraction of light inside their eyes. It’s a good thing this delicious adult wasn’t sitting in this shoreline spot three days earlier. This is the exact spot where I photographed the raccoon searching for a late night snack.
May 28th, 2012 permalink
We think of snapping turtles and large bass as being the main predators for young ducklings, but bullfrogs can also take their toll on the annual duckling population. They are plentiful and varacious at the Brighton millpond. As the Chicago’s Shedd Aquarium states, they’ll “eat just about anything they can catch and cram in their mouths,…”
As you can see from these two shots of the same frog, their throats can expand to fit the prey. This one isn’t eating, however. He’s just advertising for a mate by croaking. It’s not evident in these photos, but ones I took in 2010 show how the sound waves of the croaks travel through the water and surely amplify the sound to the potential females. The demonic eyes are just “eye shine” from my camera which I presented in 2010. Bullfrogs actually have big and beautiful eyes so they can see well at night as well as bat them at their beloveds.
May 27th, 2012 permalink
Sleep well tonight. Find out more about this creature with the demonic eyes tomorrow right here.
August 21st, 2011 permalink
He isn’t dressed as well as he was the first time I photographed him, but he’s still handsome. The photographs were taken two weeks apart. How do I know it’s the same frog? I compared the markings. While they look different because of the lighting, certain parts of the patterns are identical. Both sets of photos were taken within feet of each other near the north end of the pond.
The top photograph was taken on the sidewalk. He was watching for his dinner to be attracted to the street lamps illuminating the area. Then he hopped into the grass (left). This camera angle is almost the same as the one I posted on August 7th. Bullfrogs seem to stay in the same area unless they are disturbed. Last summer, I found a bullfrog in the same spot for five nights in a row. It must be a successful hunting strategy for them.
August 7th, 2011 permalink
On a rainy night, I discovered this large bullfrog staring into the pond, lying in wait for its next crawling, floating or flying meal. He has a bright red berry beside him. Maybe it’s to lure his prey.
He was wearing a fallen leaf on his neck along with a tiny red pedal. Below is a close up at the maximum of my camera’s resolution so you can see these details along with the wonderful blue glow reflected from his eye, the result of my camera’s flash. All of the green confetti around him is duckweed, highly nutritious floating plants the pond residents eat as salad. You can see it up close by clicking the photo on the right.
August 4th, 2011 permalink
By the time I left home to go to the millpond, it was lightly raining on July 27th. Five minutes after entering the park, the deluge began and I ended up standing in the gazebo for the next 40 minutes. I spent the time attempting to find suitable photographic subjects in my immediate, limited surroundings. Light coming from the street lamp beside the gazebo was filtered through oak leaves on a low hanging branch. During the heaviest downpour, back-lit water streamed from the gazebo roof. Neither picture is a prize winner, but they express the mood of the moment. Click them to see larger versions.
The gazebo is built on a circular slap of concrete. The rings from drips puddled beside it. I liked the circle in relation to the straight lines of the sidewalk with the ripples breaking the monotony. The still picture (right) lacks the interest I saw with the splashing ripples. To try to spice it up, I moved it into the realm of a digital painting and played until I came up with the image appearing below where more color was added and the lighting improved. It’s large enough to use as a desktop pattern or chop it down to fit your monitor.
The frog at the top of this post is a young bullfrog, I think. While it’s the size of a leopard frog, its markings aren’t the same. It may be a Green Frog but lacks the folds along its sides mentioned on this page. This young bullfrog isn’t as brightly colored, but the markings are similar. In researching, I discovered a Michigan distribution map of bullfrog populations (PDF). They are present in less than 5% of Michigan but many areas haven’t been surveyed. I thought they were common throughout the state. The millpond is teaming with them.
April 9th, 2011 permalink
Almost six months ago, I photographed the last bullfrog of the season within feet of where I found this first one of spring. It’s not the same frog unless he’s changed his markings while spending the winter buried in the mud.
All of a sudden, the millpond is alive with Spring and I’m surprised. The water can’t be more than 40 degrees yet I’ve seen fish feeding and lilypads unfurling below the surface. Bullfrogs eat small creatures and insects. The pickings have to be slim for them now, but cold water might suppress their appetites. This one posed for several minutes so I could get a nice, crisp portrait. Then he turned and vanished into the deep (below).
June 18th, 2010 permalink
I’m alternately furious and fascinated by the interaction of my flash with the eyes of animals on my night walks. Furious because I wish they looked “normal” but fascinated because they sometimes surprise me. I get the “redeye” reflection you commonly see with humans, but often I get a bright, flat white or yellow. Those animals look plugged in like living nightlights on the millpond paths. Only one eye reflects on a raccoon I see often. I’ll post a photo of him soon. A while ago, I read about that phenomena, It’s a symptom of a certain medical condition, but I can’t remember which.
The eyes of Canada geese and bullfrogs, however, look like globes of spectral colors in the blue-violet-red-orange-yellow range (never any greens). I know it’s related to the size of their pupils and the curvature of their lens, but I haven’t researched it. I just enjoy it.
Clicking on the two bullfrog photos will bring you larger versions, but clicking on the goose will show you it stands in the foreground of a creche of half-grown goslings whose eyes look like a row of stars.
June 16th, 2010 permalink
It was late Friday night. After I parked my vehicle, I was confronted by this young bully. He was near a street light probably waiting for a moth to drop. I was able to set my camera right on the pavement about a foot in front of him to get the above shot. Too bad he didn’t bathe prior to our encounter. He had bits of dirt and blades of grass stuck to his wet skin in several places. He showed no fear at all. I actually had to nudge him with my toe to get him to hop into the grass. You’ll see more of him on this blog. He was very cooperative. I got several crisp images.
May 29th, 2010 permalink
I had such fun shooting in the dark that I did it again the next night. I heard another bullfrog calling nearby, pointed my camera in his general direction, and went home to find him in the picture projected on my large monitor. Success again! Can you find him in the larger version? If not, here’s the answer.
May 27th, 2010 permalink
I sometimes shoot in the dark. The millpond moans at night now with the calls of bullfrogs. A call from one side of the pond is answered by another on the other side. It’s loud and slightly amusing. While standing on the boardwalk listening to the racket, a bullfrog called from about 15 feet from me. I couldn’t see him but I aimed my camera in his direction and took a shot hoping he was in it. After I got home and projected the image on my large monitor, I found him! See if you can, too. Here’s a larger version to help you. And, if you’re stumped, here’s the answer.
February 2nd, 2010 permalink
Wikipedia tells me you can determine the sex of bullfrogs by the size of their tympana, their eardrums. This is a bullfrog instead of a cowfrog because the tympana are larger than the eyes. It was taken in the early morning of July 4, 2009 as it contemplated how to celebrate the holiday. He appeared to enjoy posing for his portrait.
Throughout the summer, he and his buddies mooed through the nights. It sounded like a Montana ranch. Note the almost florescent yellows and greens of its lower lip and jowl. Download the larger version to see more detail.