Author: Walter Meshaka

A Walk Down Another Memory Lane Brings Another Species Turnover

Barnacle Historic State Park in Coconut Grove, Florida, where crested anoles have replaced brown anoles over the past 15 years.

Not long ago, I posted results from a return visit to a beloved South Miami site, the Doc Thomas House, that experienced a change in the dominant anole species following a change in canopy development. Another fine place that shares a then-and-now story is the Barnacle Historic State Park in Coconut Grove, also in south Florida. The first visit to the Barnacle was in 2005 when we conducted a herp bioblitz at this wonderful coastal park.

On 6 July 2007, anoles were counted and their perch heights recorded at the Barnacle. Anolis cristatellus was there and in the surrounding, area but it was greatly outnumbered by long-time resident, A. sagrei, at the park. In 2007, A. cristatellus occupied higher perch sites than A. sagrei. Alas, time was not kind to A. sagrei. A return visit to the site on 14 February 2020 revealed a very different arrangement of things. Anolis cristatellus was now everywhere and much more numerous than A. sagrei had been in 2007. Only one A. sagrei, and a possible hybrid, was seen in 2020, and the perch heights of A. cristatellus shifted in the opposite direction. The habitat historically had been open and so favorable to A. sagrei. Between 2005 and 2020, the hammock had remained well-canopied, and the side walls were well-shaded, to the liking of A. cristatellus. Thus, unlike at the Doc Thomas House, where canopy development facilitated colonization by A. cristatellus from surrounding area, the Barnacle habitat was predisposed to its colonization.

 

 

A Return to the Doc Thomas House and Anoline Turnover as Habitat Changes

Last year in early March while visiting family back home in south Florida, my daughter asked me if I’d drive her to a friend’s house in South Miami. The drive took us right past The Doc Thomas House, site of a herp survey I conducted in the 1990s, not long after Hurricane Andrew ripped through town (download the article Florida Download the article from the Florida Field Naturalist). The Doc Thomas House is also not but a stone’s throw from the original site of introduction of Anolis cristatellus in South Miami. The whole area was part of my childhood and not-so-childhood home range.

I told my daughter the story of how so long ago it was a lot more open than it was now as we were driving past it, and how back then it was dominated by its sunnier habitat counterpart, A. sagrei. She suggested that I revisit the site. Superb idea! After dropping her off at her friend’s, I stopped by the place. I was struck by the high abundance of A. cristatellus in the now heavily-shaded 1.5 ha remnant pine rockland-tropical hardwood hammock purchased by Doc Thomas in the early 1900s when Miami was still wet behind the ears. I saw no A. sagrei.

Well, needless to say, my vestigial tail was awaggin’. Staff was supportive of a return visit, and I did return for a single day and night survey on 5 September 2019. Admittedly brief, too brief to ascertain some things, but more than enough time to discern other things. What a joy it was to visit again. Lots to wonder about. As I did in 1997, I counted herps and noted perch heights. I also flipped rocks. Things had changed a lot for anoles so influenced by shade. The update and comparison with the earlier work is published in the Kansas Herpetological Society’s journal, Collinsorum. I hope you find it worth your time to read.

 

 

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