Sirens out of the water?

[ryan]

I read something about sirens coming out of the water after a heavy rain (much like an amphiuma) has anyone experienced a siren leaving the water?

 

[John]

I have talked about this person who shall remain nameless with regard to a Siren pond in Oklahoma which he and some friends found (and I later visited to get some photos only). The pond seemed to be man-made and as as my friends puts it, "out of the flood plain". I very much believe that there had to be an overland migration to colonize it, for what it's worth.

 

[froggy]

Could eggs/larvae have been deposited in plants or silt by birds or the pond's constructors?

 

[onetwentysix]

Could eggs/larvae have been deposited in plants or silt by birds or the pond's constructors?

While possible, I think this would be pretty unlikely, though there's a good chance this has happened somewhere sometime. Siren eggs aren't easily dislodged from the plants they're attached to, aren't very commonly found in the wild, and would probably have a hard time coming off the bird if they did get attached. While it's possible (and again, probable that this has happened somewhere), I think it would be an unlikely explaination for any given pond. Likewise, the bird could have carried the plants, but how often do birds carry pieces of water plants? Small clips are likely, but those pieces are much less likely to contain an egg, etc.

I'd think that floods would be the most likely explaination for siren migration. Ponds overfill, or channels of water appear and the animals swim through them, wind up in ditches, etc., and can disperse some distance. This can get them closer to the uninhabited pond, and then if the floods recede, some may be able to crawl short distances on land while there's still abundant surface water. Most will probably die (or aestivate and wait for the next flood; they might be able to leapfrog a bit if flooding is common) but some may be able to find a new source of water previously unconnected to water they'd be in before. It doesn't necessarily have to be in an actual flood plain, but one to two inches of water should be plenty for a siren to swim up. I'd imagine that any two bodies of water relatively close together would be at least partially connected during a heavy rain, since water generally heads in the same direction and runoffs are likely to meet somewhere downstream.

Of course, I'm not basing this on any actual research, just what I've seen in sirens. They really don't move very well on land and have no reason to leave the water on purpose. Amphiumas at least don't need to deal with gills as well, and do perfectly well out of water if necessary (such as when they're found above receded water nursing clutches.) And even amphiuma overland movement is pretty rare I think.

 

[froggy]

I agree that movement attached to birds etc is fairly farfetched (probably should have applied some basic logic to it before suggesting!), is it not possible that the builders of this pond brought plants from a nearby habitat that was in the flood plain and a siren habitat? They may have even brought sirens they found with them deliberately. Was the pond designed as a pond or is it actually a livestock drinking tank or something like that?
The 'leapfrogging' idea is a good explanation too. Any idea when the pond itself was built, and have therebeen any major floods since then?

This is an interesting thread to speculate over!

Chris

 

[bsears]

Eggs being attached to birds' legs is not very far fetched, as it has been proposed quite often for fish dispersal. Sirens have been found crawling 100 yards from a water source, and while they do not certainly do not disperse with much grace or ease, it is an option in their life history. Sirens can aestivate when their pond begins to dry, but they can usually only do so once in their lifetime; therefore, there may be substantial selective pressure for them to migrate to a new pond. Doing so during a heavy rain would likely reduce the risks of dessication and predation.