northeast-flora-and-fauna

Here's a strikingly goodlooking Green Frog from last year [1]. This frog is likely a male; his tympanum (eardrum) appears to be larger than his eye, and he has a yellow rather than white throat, both being field marks for male Green Frogs. (FWIW the American Bullfrog males can also be identified by tympanums that are larger than their eyes.) June 29, 2023 at Sourland Mountain Preserve Photo 301252530, (c) jpviolette, some rights reserved (CC BY-NC) [1] And this is saying something given how goodlooking the average Green Frog is.

This Green Frog looks to have found a mossy spot to "fish" for flies. It's not a great angle, but it achieves 1 thing that this picture doesn't achieve: easy identifiability. One thing you can easily see is 1 of the ridges going straight down its back, clearly distinguishing it from its American Bullfrog cousin. Other than that, the moss makes an interesting spot to sit. While both the frog and moss are green, which should provide some camouflage, the shades of green aren't particularly close. The frog might actually blend in better with a muddy background, perhaps resembling some slimy vegetation in the mud. On the other hand, moss does sound like a comfortable place to sit while waiting for dinner to fly by. May 12, 2023 at Lord Stirling Park Photo 282422844, (c) jpviolette, some rights reserved (CC BY-NC)

This American Bullfrog thought it had found a spot where no giant, potentially dangerous animals would spot it, but then I came along. Even if you're not crazy about frogs [1] this is 1 cool-looking frog. And this spot at Lord Stirling Park gives the surrounding area an almost jungle-like vibe. Although I got an ID of American Bullfrog, I'm waffling a little on the ID. The dorsolateral ridges that usually distinguish the species can't be seen from this angle, and both American Bullfrogs and Green Frogs can have white throats/undersides [2]. May 12, 2023 at Lord Stirling Park Photo 282422437, (c) jpviolette, some rights reserved (CC BY-NC) [1] Of course I'm joking. What sort of wacky weirdo wouldn't be crazy about frogs? [2] Males of both species can have a yellow throat, making it more likely this is a female.

Here are a couple American Bullfrogs ; though they didn't seem to be busy, you could say they were swamped. Great Swamp National Wildlife Refuge [1], that is. It can take a lot of time to eat, duck predators, and avoid cameras, and it can be easy to fall behind in these important endeavors. I was a little curious about the skin differences between these 2 bullfrogs. The 1st has very smooth skin while the other has little bumps on its back. I initially wondered if this was a way to distinguish between males and females, but it may be a virus . Apparently frogs sometimes get herpes. AFAIK this isn't especially detrimental to the health of a frog; at least none of them have expressed a problem. May 11, 2023 at Great Swamp Photo 282421232, (c) jpviolette, some rights reserved (CC BY-NC) May 11, 2023 at Great Swamp Photo 282421278, (c) jpviolette, some rights reserved (CC BY-NC) [1] If there is a Great Swamp, logic suggests there are other, less great swamps out there. I was able to...

After seeing a bunch of American Bullfrogs 1 day last May, I finally met another frog, this Green Frog . (Yeah, I know, this Green Frog isn't as green as the species name would suggest; that's just a Green Frog thing .) As I've mentioned before, the ridges going down its back [1] (you can see the right side ridge pretty easily in the picture below) distinguish it from its American Bullfrog cousins. They also speak different languages. While the American Bullfrog has a deep, foghorny call, the Green Frog has a much twangier call. Also, AFAIK American Bullfrogs don't vocalize when jumping in the water, but if a Green Frog jumps in [2] I'll frequently here a call of "Eek!". Presumably this alerts the other frogs that something dangerous is around. Why Green Frogs raise an alarm while American Bullfrogs refuse to alert others is unknown to me. What's this frog thinking about? My guess is that it's got more to do with eating an insect than it does abo...

The American Bullfrogs were out in force on this spring day. I met 6, and here are the 2 most photogenic. To you and me, these guys are handsome herptiles , but for many of the arthropods flying, crawling, and swimming around here, they are voracious predators. Of the herptiles of New Jersey, I probably see turtles the most, followed by frogs [1], then by snakes, and with salamanders far behind. Herptiles are an interesting classification of animals, comprising amphibians and reptiles . What's interesting about that? Well, mostly it's that reptiles aren't especially closely related to amphibians. Birds, which we think about as a rival group to reptiles, are taxonomically a type of reptile. And even mammals are more closely related to reptiles than amphibians are. But because historically people think about reptiles and amphibians together, the 2 land-based ectotherms are studied together, despite what we now know about relatedness. May 10, 2023 at Delaware Raritan Canal P...

Here's another pond denizen I met in the Sourland pond during my springtime visit: an American Bullfrog . The tympana "ear" looks larger than the eye so I think this is a male bullfrog who's slightly obscured under a stick: If you want to over- anthropomorphize his motivation for this location, perhaps he was trying to be discreet while the pond's toads were engaging in public displays of affection . More likely, frogs feel less exposed to danger when they're a little bit under cover, like these guys . (Although sticks can be a landing spot for some of our dragonflies, our frog friend looks poorly positioned to see, let alone eat, them.) There is zero evidence that a game of fetch was going on, and the frog was retrieving the stick. April 14, 2023 Photo 272126203, (c) jpviolette, some rights reserved (CC BY-NC)  

As I've mentioned from time to time, common names can sometimes be misleading (and there are extreme examples ). Today I'll mention the Green Frog . As I've mentioned before, they're not necessarily green , their (generally) larger cousins the American Bullfrogs can be quite green, and the best way to tell them apart concerns dorsolateral ridges . On a springtime trip to Great Swamp National Wildlife Refuge I encountered a greenish Green Frog: April 13, 2023 at Great Swamp Photo 272118834, (c) jpviolette, some rights reserved (CC BY-NC) And also a brownish Green Frog: April 13, 2023 at Great Swamp Photo 272118857, (c) jpviolette, some rights reserved (CC BY-NC)

For good or ill, female American Bullfrog are not called American Cow frogs. (Apparently this is what a cowfrog looks like, though I'm skeptical of the biological reliability of that webpage.) You know the way you heard about all the invasive species that are altering (almost never for the better) our local ecosystems? The American Bullfrog is a local species that's accused of invading other ecosystems; they're our little green invaders. I'm pretty confident this is a female American Bullfrog because the eardrum (more properly a tympana ) isn't larger than the eye. In fact in this individual the tympana looks slightly smaller. (Presumably male American Bullfrogs find that to be terribly attractive.) August 30, 2022 at Washington Valley Park Photo 229847565, (c) jpviolette, some rights reserved (CC BY-NC)

I've talked before about turtles basking in the sun; as ectotherms they need solar help to regulate their body temperature. And I've shown dragonflies that try to limit their sun exposure on hot days using body positioning . Back in mid-July I saw a couple frogs making use of shading.  Admittedly I also saw some frogs completely in the sun and others beneath the heavy shade of a tree, but these 2 appeared to be seeking out shade.  I also wonder if they're getting a little protection from avian predators. While their biggest threat from birds probably comes from herons that find prey by wading through water and would get a side view of the frogs, it's at least conceivable that guys like ospreys, cormorants, or kingfishers could be looking to swoop down from above to get a froggy meal. American Bullfrog July 15, 2022 at Sourland Mountain Preserve Photo 221317752, (c) jpviolette, some rights reserved (CC BY-NC) Green Frog July 15, 2022 at Sourland Mountain Preserve Photo...

A few weeks ago I got a picture of an American Bullfrog that looks kind of chubby. This was taken in the rain garden just west of the Duke Farms parking lot, probably aided by the water level being a little low. This meant the dense vegetation that's usually there wasn't interfering with my line of sight. (FWIW the water level is even lower now.) I don't know if the frog looked chubby because the location was providing an excellent supply of food, or if something more reproductive was going on. Female bullfrogs that are ready to lay eggs tend to look plumper. If this is a female preparing to lay eggs, she'll be selecting a handsome male bullfrog soon as her mate. They'll find a romantic spot in the water, he'll climb on top of her, and she'll release her eggs (up to 20,000 of them) directly into the water, and he'll release his sperm onto those eggs in the water ( external fertilization ).  So next year I should see 20,000 bullfrogs in this spot, right?...

Though I got some pictures of Wood Frogs earlier in the season and had been hearing the small/elusive Spring Peepers about that time, it was only about 5 weeks ago that I started seeing one of our most visible frogs, the American Bullfrogs . I've talked before about how to differentiate them from their Green Frog cousins (hint: it's all about the dorsolateral ridges), a fairly similar frog that starts appearing about the same time of year. This wasn't my first bullfrog picture of the season but was one of the most handsome. I think they tend to look a little discolored and emaciated very early in the spring. A few weeks later they seem to regain their plumper and greener appearance. May 13, 2022 at Duke Farms Photo 199462915, (c) jpviolette, some rights reserved (CC BY-NC) By way of comparison, here's one of the 1st pictures I got last year. April 13, 2021 at Delaware Raritan Canal Photo 121031804, (c) jpviolette, some rights reserved (CC BY-NC)

Late last summer I was finding quite a few Pickerel Frogs at the Washington Valley Reservoir. I guess you could say that things were really hopping down at the ole reservoir.  These frogs are a little smaller than the other frogs I typically run across ( American Bullfrogs , Green Frogs , Leopard Frogs ) but are fairly noticeable and distinctive looking. They're not like those Spring Peepers , who you can hear a bunch of them around you and still not find a frog. And these Pickerel Frogs were found a little way away from water; many frogs escape my camera by simply jumping in the water. The 2nd frog did try and hide in the local vegetation though. September 7, 2021 at the Washington Valley Reservoir Photo 167829440, (c) jpviolette, some rights reserved (CC BY-NC) September 7, 2021 at the Washington Valley Reservoir Photo 167829767, (c) jpviolette, some rights reserved (CC BY-NC)

Today I want to show two different frog species, both with similar coloring and size, the American Bullfrog and the Green Frog . These are both largish frogs that tend to stay close to water and are fairly abundant in central NJ. With quite a bit of overlap in size and coloring, the easiest way to differentiate them is that Green Frogs have a dorsolateral ridge on each side going from the eye down its back. The American Bullfrog has a ridge that starts at the eye, continues just past the eardrum, and then veers downward instead of across the back. These frogs were both at Sourland Mountain Preserve. I was a little surprised that the small pond seemed to only have the Bullfrogs but when I went up the mountain to an even smaller pond I saw only Green Frogs. It's almost like these guys agreed to split the park up. American Bullfrog June 25, 2021 at Sourland Mountain Preserve Photo 141961699, (c) jpviolette, some rights reserved (CC BY-NC) Green Frog June 25, 2021 at Sourland Mountain...

A couple months ago at Sourland Mountain Preserve, I ran across this American Bullfrog . The little pond adjacent to the parking area was just teeming with interesting critters that day; I had already photographed geese, ducks, a butterfly, and a snake before spotting a few bullfrogs. It's easy to get a circle of life theme evident at this little pond. Certainly the butterflies and dragonflies at the pond could be food for the bullfrogs. The bullfrogs could be a meal for the Northern Watersnake, and (probably when they're younger) the Mallards. The Canada Goose droppings recycle nutrients for the plant life (even though there may be a bit of an overexposure of these droppings). The snakes didn't have obvious predators that I could see, though I wouldn't be surprised if a snapping turtle could be lurking in there somewhere. And of course a visit from a hungry Great Blue Heron would be happy to eat the snakes and frogs. There were no doubt a lot of predator-prey relation...

Here's an American Bullfrog who was enjoying a mud bath. I suspect this mud bath is a good way to keep the frog hydrated rather than acquiring "anti-inflammatory, detoxifying, analgesic, relaxing and revitalizing properties" that motivates humans. Though a mud bath might seem like a way to beat the heat right now, the picture was taken in mid-May; it's possible the frog was actually trying to warm up while staying near water. May 13, 2021 at the Raritan River Greenway Photo 132038940, (c) jpviolette, some rights reserved (CC BY-NC)

Yesterday's American Bullfrog has a similar-looking relative, the Green Frog . The main difference between them and the American Bullfrog is a pair of dorsolateral ridges that go down the back. (Most of the frogs in their genus ( Rana ) have these dorsolateral ridges, though most of the others don't look so similar to the bullfrog.) Despite the name, the Green Frog isn't necessarily green; some of them are more of a brown color. The largest Green Frogs are probably only a as big as a smallish American Bullfrog, but I seem to see a fair amount of overlap between the ones in my area. I think they're the frog I run across the most, though there are places where the American Bullfrog gives them a run for their money. Basically these seem to be similar frogs that live in the same places, eat the same food, and have the same predators. April 27, 2021 at the Delaware-Raritan Canal Photo 127321412, (c) jpviolette, some rights reserved (CC BY-NC)

Here's the first American Bullfrog I've met this year. They might be the 2nd easiest-to-spot frog in NJ, probably behind the Green Frog . And the two frogs look fairly similar too. Technically American Bullfrogs can get bigger, though size can be difficult to judge from a distance, and many of our bullfrogs aren't at their maximum possible size. The most obvious difference is that Green Frogs has a pair of prominent ridges going down their backs that differentiates them from the American Bullfrog. These guys are voracious eaters of pretty much any animal small enough to swallow; it's not just flies that they eat. This guy looks a little bony; I suspect that the frog hasn't had a lot of time to eat since its winter dormancy. April 13, 2021 at the Delaware-Raritan Canal Photo 121031804, (c) jpviolette, some rights reserved (CC BY-NC)