Water Loving Green Anoles

Photo by Janson Jones

We’ve previously discussed how green anoles, Anolis carolinensis, are much more terrestrial in areas where A. sagrei doesn’t occur. Janson Jones, who has written on this previously, now adds a new twist–at one sagrei-less site in Georgia, they’re frolicking around in the water lilies and other aquatic vegetation. Read all about it here.

That got me thinking. Maybe this is how the famed “aquatic” anoles evolve? First you hang out on weeds in the water, next you’re jumping in for a dip?

And speaking of anoles, not only do they float, but they can swim, even those that rarely, if ever, enter the water. I’ve inadvertantly put A. sagrei into the ocean a number of times (think lizard noosing malfunction), and they just press their legs against their body and swim by undulating their tail, alligator-style. Green anoles do that, too, and I’ll bet all anoles innately can swim. I wonder what would happen if you put a crown giant in water. Anyone want to try that with their pet in the bathtub? I bet they can swim, too. So, anoles are pre-adapted (exapted, if you will) for becoming adding aquatic habitats to their repertoire.

And that leads me to one more thought in this ramble: Carl Gans published an obscure paper (Locomotor responses of Calotes to water (Agamidae: Sauria). J. Bombay Natural History Society, vol. 74:361-363, 1977) years ago about some Asian agamid lizards (Calotes) that he dropped into a swimming pool. At first they swam as described above, but then started flailing their legs ineffectually. Eventually, their head would drop below the water, they would breathe in some water, sink to the bottom and then start walking around, presumably until they would have drowned if not rescued. Doesn’t seem like they have much of a future in adapting to aquatic habitats. Similarly, if you dunk a baby duck under water (not that I’ve ever done that), they hold their breath, but baby chickens try to breathe, and things don’t go well. Take home lesson: basic motor patterns and behaviors are needed if a species is to have any hope of adapting to a new habitat. If it doesn’t have the necessary prerequisites to survive there, they have no chance of adapting. (This is, more or less, the theme of another Gans paper I stumbled across when looking for the one mentioned above).

About Jonathan Losos

Professor and Curator of Herpetology at the Museum of Comparative Zoology at Harvard University. I've spent my entire professional career studying anoles and have discovered that the more I learn about anoles, the more I realize I don't know.

13 thoughts on “Water Loving Green Anoles

  1. Does anyone know if non-aquatic anoles eventually exhibit the ineffectual limb flailing that Calotes do if left long enough in the water?

    1. I believe Schoener wrote a paper that showed that sagrei can float indefinitely. I believe it’s cited in the Williams festschrift.

  2. Swimming green anoles — Did my second post about the green A. maynardi swimming/soaking voluntarily in our bird bath come through? I hope so.

    Ours swims exactly as described — puts it’s arms in & wiggles bodily like a crocodile in miniature. Ours, though, do not show any signs of drowning but float around carefully keeping their noses out of the water & playing dead. We wondered if it was absorbing water through its skin as it is very dry here on Little Cayman now.

    Another thought is that this might be related to upcoming molting. How often do anoles molt?

    Just as an aside, we have A. sagrei here too and they also drink out of the birdbath, but we have never seen them deliberately swimming. Yet.

  3. Some anoles might be more “aquatic” than we generally realize. See: Powell, R. and J.S. Parmerlee, Jr. 1993. Anolis chlorocyanus. Aquatic activity. Herpetological Review 24: 59.

  4. In the MANY hrs spent observing carolinensis on the Augusta Canal, I saw the occasional lizard dive into the water – usually as an escape from another lizard pursuing them in one context or another. Saw a few that even made their way back to shore.

  5. An update to the linked post: It’s now mid-April and I’m no longer seeing the Carolina green anoles low-riding the canal line at Grand Bay. For about two-weeks in March, this water activity was pretty consistent during the day. Now? Not so much. I’m just not seeing them on the water at all.

    No significant changes in water level, no major storms, or any other environmental anomalies I can think of.

    One difference: I’ve also been dip netting the edge of the canal line for arthropods and tadpoles. In March, most every netting would yield at least a few dragonfly nymphs, a tadpole or two, crayfish, and lovely little belostomas. In mid-April, not much activity at all. Granted, the shoreline is not the same as a dozen feet or so *from* shore, but I wonder if the anoles were taking advantage of springtime hyperactivity in the water? Easy fixins… The water was damn-near hopping in March. One month later, things are much, much calmer on all fronts.

    Another change, probably more relevant: the Nerodia watersnakes (mainly N. fasciata) are also now up and about, which can’t be a good thing for anoles low-riding the water. heh. Granted, there were Nerodias here and there in March, but they’re in full-on spring action mode now. Nerodias in full spring mode are hyper-active, manic creatures of lust and mayhem (<– says the overly-romantic comp/rhet instructor). They're actively patrolling the shoreline, though they also do sweeps through the central region of the canal too. If I were an anole, that would be my cue to get the hell out of the water.

    ~ janson

  6. Excellent hypothesis about the availability of a buffet going on in the canal during some weeks. Please, keep watching!

  7. Maybe I shouldn’t admit this, but as a kid, I had pet A. carolinensis and used to swim them in a friend’s pond to “exercise” them. They never drown and like others have mentioned, just floated in the water when they were tired.

  8. It seems to me that an affinity for water and the ability to float easily may explain the dispersal of Anolis species throughout the Caribbean. Including the floating over of carolinensis & sagrei (most likely from western Cuba during ancient storms, perhaps aided by plant debris)

  9. I just found a carolina anole in the screen of my pool pump alive after at least 8 hours completely submerged. He’s breathing well and very frisky. I’m shocked!

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