Gelatinous goo blobs at Hand Lake

[adamschneider]

Yesterday, I stopped at Hand Lake on my way back from Central Oregon. On the sandy south shore of the lake, I found several clear gelatinous blobs that kind of looked like dead jellyfish.

I broke one of them up with a rock, and it was firm enough that it didn't lose its thickness when cut into pieces.

A google search for "gelatinous blob in lake" mostly turns up either amphibian egg masses or bryozoans. But egg masses usually have visible eggs, and bryozoan colonies are not transparent. On iNaturalist, I found that someone else had posted the same blobs, only they said they found them floating under the surface of the water, not washed up on the sand.

So, anyone have any ideas? Is it flora. fauna, both, or neither?

[drm]

Any indication that it was alive? My guess re flora or fauna is that it is neither, that it is the waste product of something. Maybe even the degraded/decomposed result of something manmade.

[adamschneider]

Any indication that it was alive? My guess re flora or fauna is that it is neither, that it is the waste product of something. Maybe even the degraded/decomposed result of something manmade.

Man-made seems unlikely given the location (Mt. Washington Wilderness, and not a very popular spot).

I'm leaning toward "egg mass," because it does look a lot like pictures of frog egg blobs, and someone told me they once encountered thousands of tiny frogs there -- but you'd think that by mid-August, you'd see some kind of visible development.

[bobcat]

I'd go for a salamander gelatin mass. I see traces of algae in the mass, which is typical of Ambystoma salamanders. Typically, the protective mass will break apart in the water as the salamander larvae depart, but Hand Lake's water levels drop so precipitously, they may have gotten stranded.

Frog tadpoles eat their gelatin until there's nothing left.

The big globby bryozoans are fascinating, but I don't think they're found in Oregon's mountain lakes (and, yes, it's too clear for a bryozoa mass). They can be seen in the Willamette this time of year, though, which is when they're in their prime!

[adamschneider]

I'd go for a salamander gelatin mass. I see traces of algae in the mass, which is typical of Ambystoma salamanders. Typically, the protective mass will break apart in the water as the salamander larvae depart, but Hand Lake's water levels drop so precipitously, they may have gotten stranded.

Some googling leads me to believe you're correct: the single mass without eggy contours points to salamander rather than frog, and the stiff texture and algae bits point to Ambystoma.

So you think this is a "used" egg mass that the critters have already exited, rather than a fresh one where the eggs are so small that you can't see them? (Or are they ALWAYS visible, even when freshly laid?)

[bobcat]

Northwestern salamander (Ambystoma gracile):

Yes, you can always see the eggs in the mass (before they've developed into larvae). I know long-toed salamanders best because I do a lot of volunteering at Oaks Bottom. Long-toes breed in the vernal pools there and the larvae emerge by the end of winter; same for northwesterns at lower elevations. I imagine near the Cascade crest, northwestern larvae are emerging in June or so, but Washington Dept. of Fish & Wildlife says "The empty gelatinous egg masses persist for weeks to months after hatching is complete."

[adamschneider]

Interesting that the WDFW page says that A. gracile is the only one with a firm egg mass. That would seem to nail it down.