In all the time we’ve been here, I’ve only ever seen one frog. Just one. We hear them frequently, sometimes down by the creeks, other times up on the slopes above us, but they’re rather shy, and we have some very dense woodland here, so being able to find our elusive resident frogs hasn’t been easy.
This last weekend Mr. Curbstone went to retrieve the step ladder from behind the workshop, and as he carried the ladder down the hill toward the goat barn, suddenly…”plop”. He noticed that something fell out of the ladder, and landed on the driveway. A frog!
There it was, just sitting there, looking rather nonchalant. The frog seemed to have survived its aerial descent unscathed. I debated whether or not to try going in the house for my camera. From where the frog was sitting, it was an uphill dash, and usually in these situations, by the time I return, my subjects have either scurried, slithered, or hopped away!
Not this time though. Not only did this frog pose for a few preliminary shots, but it also stayed put while I ran back into the house a second time for my macro filter!
I had no idea who I was looking at, and I’m sure the feeling was mutual. However, scanning through the California Herps website, it didn’t take long to figure out who she was, although this species has had a slight identity crisis in recent years.
This species was once called the Pacific Chorus, or Pacific Treefrog (Pseudacris regilla), but in recent years taxonomists reclassified individuals in that group into three separate species. Pseudacris regilla is now known as the Northern Pacific Treefrog, and reserved for those individuals living along the far northern coast around Humboldt county, up through Washington state. Here in Central California, our local species is the Sierran Treefrog (Pseudacris sierra). The third species resides in southern California, called the The Baja California Treefrog (Pseudacris hypochondriaca).
As if that’s not confusing enough, depending on who you talk to, the common name for our Central California species is either the Sierran Treefrog, the Sierra Chorus Frog, or the Pacific Chorus Frog.
Personally, I prefer the Pacific Chorus Frog designation, as I can’t even see the Sierras from here, and I think Treefrog is somewhat misleading too, as these frogs reportedly spend most of their time on the ground.
All three of these Pseudocris species in California are extremely variable in color, but they can be identified by the dark brown stripe that runs through the eye, and a beautiful eye it is too. Viewed close up the eye reminds me of copper foil.
The markings on this particular individual were quite stunning. Pale green, with a pinkish-bronze splash across parts of the dorsal surface. To appreciate the wide variety of markings in this species, see here. The variability is quite remarkable within this species.
This individual appeared large enough to be an adult. Sierran Tree Frogs range in size from 0.75-2.0 inches in length, and this individual was toward the upper limit of the size reported for the species.
Presumably this particular frog was female. Males of this species have noticeably dark and wrinkled skin under their throats. Admittedly, it was challenging viewing underneath this frog, but her skin appeared very pale.
Sierran Treefrogs are found in various habitats throughout the state, including grasslands and chaparral, woodlands, and even urban areas.
This species breeds, and lays eggs, in slow moving water, between November to July. A single female can lay upwards of 750 eggs in a season, which take approximately three weeks to hatch.
I do wonder if the sudden rush of water in our area creeks this March had an impact on any eggs laid earlier in the season. The creeks were getting quite low in February, due to our lack of rains. As we were wrapping up construction on the goat barn, I remember hearing a deafeningly loud chorus of frogs down near the bridge that crosses over one of those creeks. We then had some heavy rains, and the creeks rapidly swelled, which seemed to silence the croaking for a while. I still occasionally hear a few croaks around dusk, but not as often as earlier in the season.
As with many frog species, the adults subsist primarily on a diet of insects and invertebrates, and the tadpoles consume various algae, protozoa, and bacteria.
This species now brings us to six known species of amphibians that we’ve found living on the farm. The Sierran Tree Frog is apparently the most common frog species in California, but common doesn’t make it any less special. Finding so many amphibians thriving here suggests to me that their environment is relatively healthy, and it’s a constant reminder as to why it’s important to be careful not to pollute our local waterways.
As this frog wasn’t safe where she was, I carefully guided her off the road, and over toward some of the native strawberry plants at the edge of the woodland, where she blended in with her surroundings quite well.
I just hope it’s not another five years before I spot the next one…
We leave all wild animal species at Curbstone Valley in their natural environments, and are careful not to damage sensitive habitat and hiding places. Note that it is illegal to collect and possess native amphibian species in California without the required licenses and/or permits.
 Other species of amphibians sighted at Curbstone Valley Farm include: California Slender Salamander (Batrachoseps attenuatus), Coast Range Newt (Taricha torosa torosa), California Giant Salamander (Dicamptodon ensatus), Arboreal Salamander (Aneides lugubris), and the Yellow-eyed Ensatina (Ensatina eschscholtzii xanthoptica).