Saturday, November 9, 2013

Florida: Exotics and Others

Knight Anole (Anolis equestris)
While in Florida in April 2012 I spotted a sizable, startling bright green lizard descending the trunk of a palm in my parents' Boca Raton back garden. How long it had been hiding in the palm's crown I had no idea, but I certainly knew that in all my years of visiting my Mom and Dad, and of peering into their back garden, I had never seen such a creature before. 

Knight Anole (Anolis equestris)
It was a Knight Anole (Anolis equestris), and though it excited me considerably to see it, it didn't belong there.

Knight Anole (Anolis equestris)
Knight Anole (Anolis equestris)
The Knight Anole, largest of the anoles, hails not from Florida but from Cuba. Its presence in my parents' garden - and in many other parts of South Florida - is a consequence of its popularity in the pet trade. People brought Knight Anoles to Florida for the pet trade, and - like a host of reptiles, birds and other animals (not to mention plants) - after they arrived, at least some of them got away.  It has been working its way northwards from Miami ever since the 1950s, and only reached Pam Beach County in 1997.

Brown Anole (Anolis sagrei)
The result is that you are far more likely to see an exotic lizard in South Florida than a native one. That is certainly true of anoles. I see anoles all the time in Florida, but they are almost invariably Brown Anoles (Anolis sagrei), another import from the West Indies. Brown Anoles are everywhere, from nature reserves to people's doorsteps. 

Brown Anole (Anolis sagrei)
Here is a displaying male, from Richardson Historic Park and Nature Reserve in Wilton Manors.

Green Anole (Anolis carolinensis)
By contrast, coming across a native anole is something of an event. There are many species of native anole in the West Indies, including giants like the Knight Anole, but only one in the United States, the Green Anole (Anolis carolinensis).  This is the lizard that used to be sold as a "chameleon" when I was a child, though despite its ability to change colour it has nothing to do with the real chameleons of the Old World. 

Green Anole (Anolis carolinensis)
Green Anoles are still common in much of the southeastern United States (and have themselves been introduced as exotics in , among other places, Hawaii). In South Florida, though, they appear to have been seriously outcompeted by the Brown Anole, and their populations have become considerably depleted. There have been suggestions that at least some "Green Anoles" here may be hybrids between native Greens and another exotic, the closely-related Cuban Green Anole (Anolis porcatus), but the evidence for this is comparatively weak.

Green Anole (Anolis carolinensis)
Green Anole (Anolis carolinensis)
Green Anole (Anolis carolinensis)
I was very pleased to find a Green Anole in Hugh Taylor Birch State Park in Fort Lauderdale, displaying in a tree above me (the Green, unlike the Brown, seems to spend little time on the ground). 

Green Anole (Anolis carolinensis)
Green Anoles can turn brown, by the way; the best clue to their identity is their rather pointy snout, and, on males, their pink rather than orange dewlap.

Knight Anole (Anolis equestris)
Knight Anole (Anolis equestris)
We found more Knight Anoles along the boardwalk at the Richardson Historic Park in Wilton Manors.

Knight Anole with Regal Darner (Coryphaeschna ingens)
Knight Anole with Regal Darner (Coryphaeschna ingens)
Knight Anole with Regal Darner (Coryphaeschna ingens)
This one literally dropped out of a tree at my feet, a Regal Darner (Coryphaeschna ingens) - an immature female, I think - clenched firmly in its jaws.

Northern Curlytail Lizard (Leiocephalus carinatus armouri)
Northern Curlytail Lizard (Leiocephalus carinatus armouri)
Other exotic lizards in South Florida range from minute geckos to the immense fat Green Iguanas (Iguana iguana) that occasionally startle visitors not expecting such a tropical-looking creature (and, undoubtedly, worrying about whether these strict vegetarians might be eying their children for lunch). The most noticeable, after the Brown Anole, is another arrival from the West Indies, the Bahama or Northern Curlytail (Leiocephalus carinatus). Curlytails were first brought in in the 1940s in the hopes that they would eat insect pests in the sugarcane fields around Palm Beach.  I don't know if they did, but they certainly ate something - Curlytails seem to be everywhere now (which, in Palm Beach, is more than I can say for sugarcane).

Egyptian Goose (Alopochen aegyptiaca)
The pet trade has brought a wave of exotics of all stripes to Florida, including a long list of birds. Not all of the sometimes surprising birds you can see flying around there are truly established, maintaining self-sustaining breeding populations. Many may appear that way, but they probably survive only because their numbers are replenished by new escapees. That is true, for example, of the Egyptian Goose (Alopochen aegyptiacus), a bird that has been present in Florida since the 1960s but has never really established a foothold. It certainly doesn't look like any North American duck, and this pair, at Wakodahatchee Wetlands, sent the birders I ran across scurrying to their field guides.

Blue-crowned Parakeet (Aratinga acuticaudata)
Blue-crowned Parakeet (Aratinga acuticaudata)
Blue-crowned Parakeet (Aratinga acuticaudata)
So many parrots have escaped from dealers or pet owners in South Florida that a wag once suggested renaming Joseph Forshaw's Parrots of the World "A Field Guide to the Birds of Dade County". I found these Blue-crowned Parakeets (Aratinga acuticaudata) feeding on buds at the Richardson Historic Park. 

Blue-crowned Parakeet (Aratinga acuticaudata)
A widespread species in northern South America, the Blue-crowned was imported to the US in large numbers before the passage of the Wild Bird Conservation Act in 1992. It is still frequently kept and bred, and, like the Egyptian Goose, it's continued presence in Florida is probably the result of repeated escapes.

Northern Cardinal (Cardinalis cardinalis)
While I do enjoy seeing this array of exotics, a good part of me wishes that they weren't here.  There are a host of reasons not to import exotics - and for anyone who thinks we need to add local colour, I will finish with a perfectly native male Northern Cardinal (Cardinalis cardinalis) that dropped in on Eileen while she took a brief rest on the Richardson Park boardwalk.  How much more colour do you need?

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