Category Archives: Notes from the Field

Mangrove Twig Anoles

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Anolis angusticeps, South Bimini, Bahamas

One component of our recent field work in Bimini, Bahamas involved gathering data from anoles across various habitat types. We selected four primary habitats for sampling based partly on the notable work by Schoener (1968): blackland forest; incipient blackland; Coccothrinax coastal scrub; and mixed Avicennia, Laguncularia, and Rhizophora mangrove forest.

Mangrove forest nocturnal survey.

Mangrove forest nocturnal survey.

South Bimini is an interesting place to study anoles in that it is a relatively small island harboring four species across at least eight different habitat types.  Schoener’s excellent study of habitat use in these species indicated that mangrove forests were marginal habitat for anoles, supporting only two of the four species (A. sagrei and A. smaragdinus). During nocturnal surveys, we located both of these species roosting on Avicennia and Laguncularia leaves and branches, though in much lower numbers than other forest types. We found no anoles in Rhizophora mangle at our study site. However, we did find a number of A. angusticeps in this forest, mostly perching horizontally on Avicennia branches. We would like to know, how many others have found twig anoles in mangrove forest?

Bark Anole Battle Scars in Miami, FL

As it starts to heat up here in Miami, anole interactions are at the highest while males try to stake their claim for the most attractive territories in town. Earlier during an afternoon stroll around South Miami I came across this bark anole (Anolis distichus) that looks like it’s had a pretty rough time recently!

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I assume this injury to his nape is probably from another lizard, likely another male A. distichus, incurred during a territorial dispute, and not a predation attempt. Either way, it looks like it didn’t dent his confidence too much!

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Great Egret Eating a Crested Anole in Miami, FL

Here is a video taken by University of Miami PhD student Joanna Weremijewicz at the Fairchild Tropical Botanical Gardens in Miami, FL last Friday (20th March 2015). There have been lots of posts talking about the predation potential of egrets (and other wading birds) on anoles here on AA similar to this (1,2,3,4), but I think this could be the first one recording predation of A. cristatellus? Cool video!

Field Trip Recap: Herps of Bimini, The Bahamas

 

Searching for Anolis sagrei on the beautiful island of Bimini

Anolis sagrei on the beautiful island of Bimini

I just got back from a 10 day research trip to Bimini in the western Bahamas along with Harvard post-doc, Graham Reynolds, Harvard graduate student, Pavitra Muralidhar, and UMass Boston undergraduate, Jason Fredette. We went with the simple goals of kicking off a research project in the Losos lab on Anolis sagrei  and to observe as many other herps as we could.

We spent the majority of our time on South Bimini. We sampled from the well-maintained Nature Trail, where we found all four anole species (Anolis sagreiAnolis smaragdinusAnolis angusticeps, and Anolis distichus) and a Bimini boa among diverse habitat types, including blackland coppice and open Coccothrinax shrub. We also spent a couple of nights searching in some mangrove forest near the airport, which yielded only A. sagrei and A. angusticeps and in low abundance at that. The “Fountain of Youth” ended up being a gold mine for Sphaerodactylus nigropunctatus as well as boas — we caught 3 here.

We also did a fair amount of exploring. Our hosts for our house rental wanted to make sure we had a great time in Bimini and so they insisted on boating us out to a couple of the nearby islands for some snorkeling. Of course, we saw this as the perfect opportunity to catch a few lizards. Our first destination was Gun Cay, a small island a few miles to the south of Bimini. Pavitra and Jason entertained our hosts by collecting shells and feeding stingrays. Meanwhile, despite our hosts’ curiosity that we wanted to go wander in the brush, Graham and I nabbed 10 adult male A. sagrei in less than an hour. We also saw several Ameiva auberiAnolis smaragdinus, and some sort of very large rodent (does anyone know about Hutia reintroductions in the Bahamas?).

The following day, our hosts insisted we come with them to a small island 20+ miles to the north of Bimini (Great Isaac Cay) where they promised us dolphins and hammerhead sharks. On the way to the island we saw several dolphins, tons of flying fish, sea turtles, and several large nurse sharks. As we approached the island, I saw the mature Casuarina forest and yelled down to Graham from the crow’s nest tower, “I want to go explore there!”  Our hosts got us as close as they could to the rocky shore (dangerously close it seemed, the hull almost hit the rocky karst island) and all four of us hopped onto the island. The island had an abandoned lighthouse and buildings from the 1800’s that we explored. We were shocked to not find a single anole on Isaac Island, although we did find Sphaerodactylus nigropunctatus and Ameiva auberi.

The isolated Great Isaac Cay with ruins from the late 1800's.

The isolated Great Isaac Cay with ruins from the late 1800’s.

The trip was a huge success. In total, we came across all but five of the reptiles of Bimini. Surprisingly, we were unable to find any Bahamian racers (Alsophis vudii) other than roadkills, though most of our field time was at night. Unsurprisingly, we did not find either of the blind snakes or the dwarf boa, the latter of which tends to be more common in the rainy season. As expected, A. sagrei was the most abundant anole on Bimini. We came across A. angusticeps and A. smaragdinus with equal frequency and actually encountered only a few A. distichus. We did most of our searching at night, so this may be a reflection on different sleeping behaviors rather than abundance.

In summary, we were able to observe:

  • 140+ Anolis sagrei males and females
  • Sphaerodactylus nigropunctatus (black-dotted dwarf gecko)
  • Sphaerodactylus argus (ocellated dwarf gecko)
  • Dozens of Leiocephalus carinatus (curly-tail lizard)
  • Chilabothrus strigilatus fosteri (Bimini boa)
  • a handful of Anolis distichusAnolis smaragdinusAnolis angusticeps

We also saw a number of other herps that we were not able to catch or didn’t need data from:

  • Ameiva auberi (Bimini ameiva)
  • Eleutherodactylus planirostris (greenhouse frog)
  • Osteopilus septentrionalis (Cuban tree frog)
  • Hemidactylus mabouia (invasive house gecko)

 

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Some Sleepy Anoles from Costa Rica

I’m in southern Costa Rica doing field work with bats, but once an anole lover, always an anole lover so when I get a night off I like to go herping. Since everyone loves a sleeping anole (1, 2, 3, 4, 5, among others), I thought I’d share some photos that a friend and I took while wandering around at night. I’m not sure what the last one is; I’m guessing Anolis polylepis (we’re at 1100m at the Las Cruces Biological Station and it was sleeping about 1m above the ground).

Anolis capito. Photo by Jon Flanders

Anolis capito. Photo by Jon Flanders

Anolis aquaticus. Photo by Jon Flanders

Anolis aquaticus. Photo by Jon Flanders

Anolis polylepis? Photo by Jon Flanders

Anolis polylepis? Photo by Jon Flanders

Postura de Anolis huilae: Communal Nesting!

En el marco de mi investigación sobre la Eco-fisiología térmica de Anolis huilae, me encontré (en mi finca) con un par de posturas, una con cuatro huevos y otra con 22 huevos. Este hallazgo me sorprendió, al encontrar diferentes tamaños en los huevos.

Postura de Anolis huilae, Juntas (Ibagué-Tolima-Colombia)

Postura de Anolis huilae, Juntas (Ibagué-Tolima-Colombia)

En mi curiosidad por determinar si efectivamente se trataba de huevos de la especie en mención, me di a la tarea de abrir uno para corroborar, encontrando un individuo en un estadío de su formación (el ejemplar fue donado al Laboratorio de Herpetología de la Universida del Tolima).

Embrión de Anolis huilae.

Embrión de Anolis huilae.

He comenzado hacerle el seguimiento a esa postura, in situ, midiendo y pesando cada uno de los huevos.

Considero que este hallazgo aportará detalles acerca de la historia de vida de Anolis huilae, aún desconocida.

Updates on Anolis lividus from Montserrat’s Volcanic Exclusion Zone

Image of the 1995 eruption of the Soufrière Hills volcano on Montserrat.

Image of the 1995 eruption of the Soufrière Hills volcano on Montserrat. Photo from Wikipedia.

On July 18, 1995 something big happened on a tiny little island in the Lesser Antilles. The Soufrière Hills volcano erupted on Montserrat, an island only about 40 square miles in size that is nestled between Nevis, Antigua, and Guadeloupe. The eruption buried the (then) capital city of Plymouth under several meters of ash and pyroclastic flow. More than a dozen nearby towns were also destroyed. Residents in the south of the island had to evacuate, leaving their homes and land behind. Since then, Montserrat has experienced considerable volcanic activity. In fact, when I was on the island in 2010, I witnessed a major dome collapse, an event that was magnificent to see on the ground, and was even observable from space. I’ve spent some time trying to find Anolis lividus, Montserrat’s endemic anole, across the island, with particular focus on finding it in the south, where volcanic impact has been greatest. Montserrat is basically divided in half by the Belham River Valley, a barren bed of ash that effectively separates the habitable north of the island from the more inhospitable south. I’ve spent many hours in the south of the island searching for A. lividus over a few years. In my experience, the lizards were not abundant (if to be found at all) south of the Belham. Granted, access to this region was very restricted, so I didn’t get to spend a whole lot of time there, but I only ever saw two lizards (a mating pair) on a tree in Richmond Hill, a part of the southern half that’s in Zone C. Towns in Zone C are close to the Belham River Valley and are occasionally opened up for visitors when the volcano has been quiet for a while. Currently, Zone C has ‘unrestricted access’, meaning people can visit day and night without an escort. There is also a relatively unexplored portion of Montserrat southeast of the volcano (the South Soufrière Hills) that has plenty of good habitat and is isolated by the rest of the island by the volcano. There have been a few focused expeditions to that part of the island (for example, to collect individuals of Leptodactylus fallax, the ‘mountain chicken’ frog, for a breeding program), but I haven’t been able to get there.

My interest in A. lividus lay mostly in understanding how recolonization works. Can the lizards cross the Belham River Valley, or is it too hot and inhospitable? As access to inner zones increases, will humans mediate transport into the south of the island? If they get there, will they persist? Although I haven’t been to the island in a few years, I remain very interested in the system. I recently received news on Anolis lividus from Nicolas Tirard, a new resident on the island. He had visited Zone C (which is currently open to daytime visitors) and found an individual of A. lividus. Nicolas informed me that he spotted the lizard (a male) on the terrace of an abandoned home in Richmond Hill, which is the same neighborhood where I found lizards almost six years earlier. Nicolas spent about 30 minutes canvassing this area and only found one lizard. For anyone with experience finding anoles in the Caribbean, particularly in the Lesser Antilles, we know that they are generally much more abundant than that. So I would reckon that lizards in Zone C are probably still pretty scant. I wonder if the lizard Nicolas did find descended from previous inhabitants in that area (for example, from the mating pair I observed earlier), or whether there have been more recent dispersal events. He went back on another occasion to St. George’s Hill, which he says is more densely forested than Richmond Hill, and saw three lizards there. When I visited St. George’s Hill a few years ago it was pretty barren, so clearly the habitat is recovering there.

Anolis lividus from Richmond Hill, Montserrat.

Anolis lividus from Richmond Hill, Montserrat. Photo by Nicolas Tirard.

I asked Nicolas if he thought that humans were transporting the lizards (accidentally or otherwise) to Zone C through increased transit. Nicolas reckons the lizards can get there on their own right now. He says, “I don’t think it is a human-mediated recolonization, even if there is traffic going back and forth, because the vegetation has grown again in the Belham river, and it is probable that anole can now cross it by themselves.” The finding that the Belham is vegetated is interesting – during my visits there it was a hot, barren bed of ash. The only herps I saw there were enterprising iguanas, boldly basking on piles of hot ash. I also saw an iguana on the roof of a house once in Richmond Hill. As the exclusion zone becomes more accessible, I hope that people will try to find A. lividus (and other organisms) there and, hopefully, share their observations with the Anole Annals.

Nicholas shares his observations on his blog. He has also seen a blind snake (Typhlops) and several iguanas in the exclusion zone. Check out his blog for more.

Another image of the male Anolis lividus spotted in Richmond Hill.

Another image of the male Anolis lividus spotted in Richmond Hill. Photo by Nicolas Tirard.

Communal Nesting in Anolis angusticeps

Previous posts have discussed communal nesting behavior among a number of anole species, whereby females deposit eggs in the same cavity. A new paper by AA‘s own Michele Johnson and friends extends this growing body of observations, stretching all the way back to Stan Rand’s 1967 work. This behavior has been previously reported for the Cuban Twig Anole (Anolis angusticeps) in Cuba, though apparently not in the Bahamas. According to Robinson et al. (2014), at least nine West Indian anole species are now known to engage in communal nesting, with others potentially to be added. AA has also called attention to a tenth mainland species (A. lionotus), described in Montgomery et al. (2011). So these observations bring to mind some questions: what intrinsic factors of a nest cavity draw multiple females to oviposit there? Are female offspring returning to the site in subsequent years to lay their own eggs? Does this behavior vary individually or regionally? Let us know if you have some of your own observations.

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Communal nest of Anolis angusticeps on South Bimini. Figure 2 from Robinson et al. 2014, photo by B. Kircher.

 

Finding the “Rare” Anolis duellmani

Like many quests to find rare herps, this is a story of courage, persistence, and strength. Just kidding; it was a piece of cake.

Anolis duellmani was described by Fitch and Henderson (1973) based on four specimens from the southern slope of the Volcán San Martín Tuxtla, Veracruz, Mexico. Even though the phylogenetic position of A. duellmani is uncertain, no additional morphological variation had been described for the species. As part of a major effort led by Dr. Adrián Nieto-Montes de Oca and Dr. Steven Poe to untangle the systematics of Mesoamerican anoles, Israel Solano-Zavaleta, Levi N. Gray, and I went to Los Tuxtlas to search for the elusive species.

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More Morphological Oddities in Anolis sagrei

A few months ago, I shared with you some of the odder morphological variations my field assistants and I encountered while measuring Anolis sagrei in Gainesville, FL. We went on to measure quite a few more lizards, and saw quite a few more oddities, as well as some fairly gruesome injuries. Here are some of my favourite examples:

1. A far better picture of a doubly-regenerated tail.

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2. A jaw injury that resulted in the left and right sides of the jaws being dissociated from each other.

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3. A cut hyoid. I imagine this lizard was no longer able to extend his dewlap.

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4. A nasty head injury. We saw this lizard three or four more times after we measured him, and his wound seemed to have healed up completely.

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5. A brutal leg injury.

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6. A male with not only an impressive tail crest but also some nice red tail coloration.

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The Dewlap of Cophosaurus texanus

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Here at Anole Annals, we can appreciate a good dewlap. In particular, a pair of agamid clades, namely the genera Draco and Sitana + Otocryptis, arguably do extensible throat fans even better than Anolis. But dewlaps are actually found in many other iguanian lizards, covered by AA posts here and here.

Today I thought I’d share a lesser-known dewlap, that of Cophosaurus texanus, known as the greater (greatest?) earless lizard, and a legitimate candidate for best lizard coloration if you ask me. In my experience, these lizards don’t often dewlap, but will occasionally hit you with a few push-ups, and reliably wag their striped tails at you before darting away — though they are upstaged in this latter respect by Callisaurus draconoides. On a recent walk in the Rincon mountains near Tucson, Arizona, I encountered a particularly saucy individual, and thought I would share.

Here’s a series of photos showing a pushup/dewlap combo being delivered. By the way, Cophosaurus texanus are known to display at potential predators (see Dial 1986, American Naturalist 127:1).

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Another shot, the dewlap is being retracted here:

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As far as dewlaps go, its not the most impressive, but there certainly looks to be some cartilaginous rod action involved, as in Anolis. But wait – notice anything unusual in the above photos? Yes, there looks to be a parasite peeking out through the lizard’s nostril. Here’s a closer look:

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Pretty gnarly. I’m not sure what the parasite is, it looks to me like it could be a maggot (hey, speaking of maggots, remember anole throat maggots?). Hope I didn’t just ruin anyone’s lunch!

Anyway, if you’re interested in learning more about Cophosaurus, here is an excellent write-up written by Robert Bezy and provided by the Tucson Herp Society.

A Doubly Regenerated Tail and Other Morphological Oddities

I’m doing fieldwork with Anolis sagrei in Gainesville, FL, this summer. We now have about 125 lizards  measured and marked, and have come across a number of interesting morphological oddities in these lizards. Most interesting so far is this doubly regenerated tail, i.e. there appear to be two spots at which the tail has regenerated, which means a regenerated tail must have broken and regenerated again.

A doubly regenerated tail in a male Anolis sagrei in Gainesville, FL.

A doubly regenerated tail in a male Anolis sagrei in Gainesville, FL.

Approximately three minutes before we noticed this tail, my field assistant Christian Perez asked me if double regenerations were possible, and I confidently said “no.” As Jonathan Losos puts it in Lizards in an Evolutionary Tree, “when a tail regenerates, the new portion of is made of a rod of cartilage and thus lacks the intravertebral breakage planes that enable an unregenerated tail to autotomize.” So how did this double regeneration happen? Anyone seen this before?

The next oddity is this male with a mysteriously shortened upper jaw:

A shortened upper jaw in a male Anolis sagrei in Gainesville, FL.

A shortened upper jaw in a male Anolis sagrei in Gainesville, FL.

Third, we have a partially discoloured dewlap:

 

A discoloured dewlap in Gainesville, FL

A discoloured dewlap in Gainesville, FL

And finally, here’s an addition to our collection (1, 2) of multiply tailed lizards:

A double tail in an Anolis sagrei in Gainesville, FL.

A double tail in an Anolis sagrei in Gainesville, FL.

 

When You Can Not Get The Results You Expected, Use What You Can Get!

An adult Anolis sagrei male specimen from Santzepu, Sheishan District, Chiayi County, southwestern Taiwan.

An adult Anolis sagrei male specimen from Santzepu, Sheishan District, Chiayi County, southwestern Taiwan.

Field research does not always go the way we plan. My research partners and I were reminded of that in 2004, when we tried to use a mark-and-recapture method to determine the population sizes of brown anoles (Anolis sagrei) in a small betelnut palm (Areca catecha L) plantation in Santzepu, Sheishan District, Chiayi County, southwestern Taiwan. We ended up with too low recapture rates for our estimates. Still all was not lost! Of the lizards we did recapture, we were able to calculate monthly growth rates and monthly growth percentages. The results indicated that at least some individuals experienced active growth throughout the year. Our results also supported the findings of Schoener and Schoener (1978) and Cox et al. (2009) that smaller individuals of both sexes grew faster than larger conspecifics of the same gender, and that males grew faster than females. We also determined that growth rates of both sexes decreased during the peak reproductive period, suggesting that available energy is directed primarily to reproduction and the associated to behavior, and that energy is only directed towards growth once the requirements for reproduction are met.

The experience from this study convinced me again that it is important to collect as much data as possible when conducting field studies – it is hard to predict where it may come in handy at a later stage.

Crown-giant habitat overlap

Spring is the season for spotting crown-giant anoles in Miami!

I was hosting (recently graduated Lacertid-ophile, although closet anologist) Dr. Robert Heathcote for a few days this week, and after his failed attempt at catching a Cuban knight anole (A. equestris) a fortnight previous, I had promised to deliver him another! Now, I imagine many AA readers may chuckle at someone foolish enough to promise a crown-giant observation (myself included). Much to my relief luck was on our side and we managed to spot not one, but TWO species practically on top of each other!

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A Cuban knight anole (A. equestris) and Jamaican giant anole (A. garmani) perched within 1-2m of each other in Miami FL – April 2nd 2014, JStroud

Cuban knight anoles (A. equestris) and Jamaican giant anoles (A. garmani) are both non-native introduced species to south Florida.

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A. equestris (left) and A. garmani (right) – habitat overlap in Miami FL, JStroud

Anoles have it tough in south Florida!

A common concept in ecology is that predators have a strong influence on the behaviour of prey species. Anolis lizards have been used as a classic model system to investigate the effect of predator presence on the behavioural response of prey species. On small experimental islands in the Bahamas the manipulated introduction of curly-tailed lizards (Leiocephalus carinatus), a large terrestrial anole-predator, has resulted in brown anoles (Anolis sagrei) shifting higher up in the vegetation, presumably in an understandable effort to avoid being eaten (1, 2, 3). However, predator-prey interactions such as these which may shape community structure are often difficult to observe.

Here in Miami FL we have a rich and diverse, although largely non-native, lizard community. There are two species of “crown-giant” anoles, the Cuban knight anole (A. equestris) and the Jamaican giant anole (A. garmani), that could be potential predators of smaller anoles in the canopy of trees and upper half of tree trunks (although see Giery et al. 2013 for an empirical analysis that suggests this may not be the case). Additionally, there are several large, terrestrial lizards present which may be filling a similar role to curly-tails in the Bahamas.

Potential lizard predators in south Florida:

– *Red-headed agama (Agama agama)
– *Cuban knight anole (Anolis equestris)
– Jamaican giant anole (Anolis garmani)
– *Brown basilisk (Basiliscus vittatus)
– Spiny tailed iguana (Ctenosaura similis)
– Curly-tail lizard (Leiocephalus carinatus)
– Giant day gecko (Phelsuma grandis)
– Black and white tegu (Tupinambis merianae)

*Present at Fairchild Tropical Botanical Gardens

Earlier this afternoon, while taking a break from my office at Fairchild Tropical Botanical Gardens (a hot spot for any anologist visiting Miami; 1, 2, 3, 4) in a typical graduate student effort to put off work that I should be doing instead, fellow lab member Evan Rehm and I noticed some scuffling in a nearby bush. At around 2.5m, and admittedly on relatively precarious branches by this stage, sat an adult female African red-headed agama (A. agama) around 30cm from an adamantly motionless adult male Cuban brown anole (A. sagrei)! As we moved towards the bush the agama was quick to ungraciously thump itself to the floor, while the brown anole remained still. On closer inspection, it soon became apparent why both lizards were so high.

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Adult male Cuban brown anole (A. sagrei) found ~2.5m high in Miami FL, supposedly following a predation attempt from an African red-headed agama (A. agama) – JStroud

The significance of tail loss/damage in a population is still debated. The classical view argues that high proportions of tail damage indicates high predation pressure, therefore prey populations are under high predation stress (1). Alternatively, high proportions of tail damage could indicate low predator efficiency, which would suggest prey populations are experiencing low predation stress (1, 2). But the debate doesn’t stop there! Having already lost a tail, a lizard may experience either a resulting increase or decrease in predation depending on the predator species and its associated foraging tactic (1).

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The extent of tail damage is clearer in this photo. The lizard had autotomised the lower half of it’s tail however a secondary half-completed break is also evident – JStroud

African red-headed agamas (A. agama) are similar morphologically to curly-tailed lizards (L. carinatus), although are taxonomically distinct (Agamidae and Leiocephalidae, respectively). Predation of anoles by agamas in Miami has not previously been officially recorded, and the impact of these large predators remains unclear. Unlike in the Bahamas, there are multiple predators in the same geographic vicinity that anoles need to be aware of. For example, at Fairchild, brown anoles (A. sagrei) could be eaten from below by agamas, eaten at intermediate levels by basilisks and eaten from above by knight anoles!

South Florida is a tough place to be an anole!

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Adult male African red-headed agama (A. agama) at Fairchild Tropical Botanical Gardens, Miami FL. The population of agamas is localised to the botanical gardens; the source remains unclear but is likely an introduction from the pet trade – JStroud

Turks and Caicos Anole: Anolis scriptus

Much of my research has been conducted on the herpetofauna of the Turks and Caicos Islands (TCI). Known to a chunk of the lay public in North America as a sweet honeymoon spot, the Turks and Caicos boast a wonderful assemblage of terrestrial reptiles, like these IUCN critically endangered TCI iguanas (Cyclura carinata):

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Of course, we on AA prefer the smaller saurians, so I will draw your attention to the TCI anole (A. scriptus scriptus), a member of the Southern Bahamas Anole complex (A. scriptus).

Anolis s. scriptus, Big Ambergris Cay, TCI

Anolis s. scriptus, Big Ambergris Cay, TCI

Also known as the Silver Cay Anole, A. scriptus can be found across the southern Bahamas banks, including the Inaguas, Samana, Plana Cays, Mayaguana, and the Turks and Caicos Islands. I have previously posted about this understudied species (1,2), but spent a good bit of time observing them on my last research trip. They occur throughout the TCI archipelago, from the dense tropical dry forest of North Caicos, to the pine savannas of Middle Caicos and xeric outposts like the Ambergris Cays. They can also be found on nearly every vegetated rock cay.

 

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Male, Big Ambergris Cay

 

The males have an attractive yellow wash on the underside, with an orange-yellow dewlap that is really striking in the bright sun. The males display from elevated perches, but are wary when approached by nosy researchers.

 

The females are more cryptic, both in coloration and in behavior. They often have a light stripe down the back, or occasionally darker crossbars perpendicular to the light stripe.DSC_0977

On Big Ambergris Cay, on the southeastern edge of the Caicos Bank, the anoles especially favor an irrigated area near a decorative plant nursery. They are voracious, taking down large prey like this cicada (Ollanata caicosensis) on the right. Hopefully this voraciousness extends to interspecific interactions, as the “Festive” anole (A. sagrei) has now firmly invaded at least one island on the Caicos Bank (1; more on this in a future post).

Phylogenetically, Anolis scriptus is nested firmly within the radiation of Puerto Rican Anoles (most recently). Most closely related to a trunk-ground clade containing A. cristatellus, A. desechensis, and A. ernestwilliamsi, the TCI Anole exhibits a curious distribution, although they really do resemble A. cristatellus. Much of the terrestrial herpetofauna of the TCI is likely derived from Hispaniola (See TOC on this post), so what did A. scriptus do to get to the TCI? Our recent research on the A. cristatellus clade suggests that A. scriptus most likely dispersed from Puerto Rico around the start of the Pliocene. This could have been accomplished completely over-water, as currents and hurricanes push flotsam in a northwesterly direction from Puerto Rico. Alternatively, the species could have island-hopped on the formerly emergent Silver, Mouchoir, and Navidad banks, now a famous calving ground for the Humpback Whale.

Although I have not visited, the Crooked-Acklins Bank is a curious intersection of Bahamian and southern Bahamian herpetofauna, where the range of the southern A. scriptus (nearby Plana Cays) meets the range of the northern A. sagrei (Crooked Island). Furthermore, the bank is the northern limit of the Southern Bahamas Boa (Chilabothrus chrysogaster), which is replaced just a few kilometers northwest on the Great Bahama Bank by C. strigilatus. Finally, the handsome endemic A. brunneus (1,2,3) occurs there.

 

 

 

Wet Prairie Anolis carolinensis in Two Parcels in Broward County, Florida: Historical Populations?

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Hi Anole Folks,

So life transported me to South Florida to beat Cancer, and looks like I have made good progress, thank you in advance. :-)

As a general naturalist, I get out A LOT, each day- up to three hikes in different habitats.

In my area on the border of Broward and Palm Beach Counties, there are several restored Pine-Lands, some from about 1984- most  cordoned off in a way for even longer due to central farm use, cattle grazing, or logging with left over islands near the wetter areas.

I spent a lot of time in the late 70’s in Coral Gables, Florida-  with a two year stint at the U. of M.  At that time, Anolis carolinensis, while not common, could be found on buildings on Ponce de Leon Blvd. and also areas of Bird Road, LeJeune and others behind the U of M arboretum.  I also would find both A. porcatus and A. chlorocyanus at these locations.  Anolis sagrei was always in great numbers no matter what.

Returning NOW, in 2014- with extensive field searching, failed to find Anolis carolinensis. The typical haunts I’d expect–along homes, in bushes, on trees, and in scrub–failed to yield a single animal.  I put in a lot of effort.  I found A. porcatus, A. equestris, what I think is A. cristatellus, and every morph you can think of of A. sagrei.  I also found Curly Tails living sympatrically with A. sagrei in several pockets.  This I found pretty neat and worthy of some work.

Recently, while hiking a Wet Prairie, along a Cypress Marsh near a domed swamp area, I started to see a very thin green lizard perched atop grass stalks–and very often cattail stalks in the center of the wetland, over standing water.  I could not confirm the species–they were far into the swamp and their flushing distance was ASTOUNDING.   They would see me and DROP clear to the grass below.  One time I saw an individual turn brown in seconds, and disappear, not into tree branches, but into the grass on the ground! I watched this behavior 8-9 times before I knew–I had to hike into the swamp.  So I did.

IMGP0391Eventually I was able to see males and females, of what now I was sure was A. carolinensis hunting and using the grass/cattail stalks for feeding and display.  In the attached image, you will see one on cattail, and this is a typical daily encounter.  I could see five or more in a hike, on the tops of grass stalks near the seed heads.  While bushes and peripheral trees were there, they were not using this substrate. I really was seeing a marshland native Green Anole group.   And to my eyes, this group was rather “gracile” in form.  And they worked the stalks in what seemed to be a new fashion.  I even imagine–since I have not done any morphometrics yet–that their hind legs look longer, tibia/fibula and femur, and toes.  They also have  a posture for most of their time on the stalks that is not something I was used to seeing–legs held way back and tight to the body, as if to reduce their profile.  A thin Green Anole, that can hide on a grass blade :-).   The images here represent two separate anoles from two separate days.

Did the pressures of habitat loss, A. sagrei competition, and A. equestris predatory pressure, isolate this group and/or move them to this grassland habitat over water?  Could this be a recently adapted “ecomorph” which we so timely have read about?

I will be vouchering a male and female for work at the MCZ for others that might be interested.  But in the interim, my favorite interest, watching behavior, will continue.

I know all the BUTS about this- as in- are they even remnants of historical Broward animals at all?  Did they come in with the replanted slash pine and pond cypress?  I’m hoping one day by genetic work, and or even some new Xray work, we might be able to answer some of this.  And of course, in their normal historical lives, they almost certainly used this type of habitat in part.  But what about now?

That there are vigorous groups in these Wet Prairies of Broward attests to the tenacity of the species, and that it is surviving here.  And that  puts a smile on my face!!

If anyone would like additional information for research, and or visit the sites with me, please feel free to contact me at naturalist@gmail.com; I’ll be here for at least a few more months.

Would love any ideas, thoughts regarding this as well.  More photos to come as well.

Enjoy the images.

Sincerely,

Kenneth E. Barnett

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Brown Anoles in Tree Islands

A recent trip to the Everglades with Palm botanist Sara Edelman was meant to provide a welcome break from studying for qualifying exams, and give her the opportunity to further educate me on all things palm (which was previously limited to determining which lizards in Miami appear to live on them).

After spending the morning locating individuals of her study species, the native and state-threatened Paurotis palm (Acoelorrhaphe wrightii), we had received very little wildlife luck (which was the true reason for me volunteering to ‘help’). From past visits, I had found brown anoles (Anolis sagrei) at every car park along the Everglades National Park road down to Flamingo, likely hitch-hiking unwittingly on visitors cars, but to my knowledge they had yet to disperse convincingly out from these. On our second to last survey of the day, to this tree island off the main road just south of Mahogany Hammock, while searching for native green anoles (Anolis carolinensis) which I had yet to see, I heard some rustling in the bushes – lo and behold, sitting there as bold as day signalling straight at me was a male brown anole!

Everglades tree island characterised by Paurotis palm (Acoelorrhaphe wrightii), Saw palmetto (Serenoa repens), Buttonwood (Conocarpus sp.) and Pine (Pinus sp.), and inset brown anole (Anolis sagrei) observed inside

Everglades tree island characterised by Paurotis palm (Acoelorrhaphe wrightii), Saw palmetto (Serenoa repens), Buttonwood (Conocarpus sp.) and Pine (Pinus sp.), with [inset] brown anole (Anolis sagrei) observed inside

Now, observing brown anoles here shouldn’t be a surprise, should it? After all they are already in many surrounding places accessible by car, therefore it was only a matter of time before they spread further afield. However, areas like these in the Everglades may represent one of the last refuges of green anoles from introduced non-native species found everywhere else in south Florida (an idea I mentioned here a few months ago). Tree islands are masses of larger vegetation (unsurprisingly characterised by trees) formed gradually as vegetation clumps in the slow moving Everglades flow. Over time, debris from colonising plants raises the ground level just above surrounding water level, meaning they provide important havens for many wildlife species. During the wet season the dispersal potential for brown anoles would be limited. All of the areas surrounding tree islands are generally inundated, meaning landscape movement through the thin-stemmed sawgrass plains may be easier for more nimble footed green anoles, however somewhat less graceful for browns. This, however, is all hypothetical.

So ruling out human-mediated release or dropping by a clumsy predator, we could assume that this chap arrived there all by himself. This would suggest that brown anoles have no problems in traversing through sawgrass, although temporal factors may be important (i.e. dispersing during the dry season when water levels are low or absent).

The implications for the expansion of this species through the Everglades remain unclear, although their relationship with green anoles leads to a predictable outcome (discussed extensively on AA [1, 2, 3). Just how much effect is a highly fecund, hyper-dense, extremely competitive and resilient insectivore going to have on these small ‘island’ ecosystems?

Trunk-ground Anoles Living in High Rises

This weekend I recently saw an adult male Cuban brown anole (Anolis sagrei) perching higher than I have ever observed – roughly 4m high!

Adult male Cuban brown anole (Anolis sagrei) perching uncharacteristically high

Adult male Cuban brown anole (Anolis sagrei) perching uncharacteristically high

So anole aficionados, what dizzying heights have you observed trunk-ground anoles up to?

*My apologies for the poor quality of the zoomed in sections.

Jamaican Twig Anole Observations

Earlier this year ,while conducting crocodile (C. acutus) research in Jamaica, I observed some interesting behavior with the Jamaican Twig Anole (A. valencienni). The croc research is conducted at dusk and into the night, which leaves ample time to watch the anoles (during the day) that share our campsite. All of the Jamaican anole species are present at our camp in the Hellshire Hills except A. garmani. The camp is located just off the beach in a sea grape and buttonwood dominated coastal forest.

While lying in a hammock, I watched a female A. valencienni descend a branch toward a tree hollow. As she approached the hollow, I noticed several other females near the entrance hole. I know that it is documented that this species is a communal nester, but to see it was a real treat. During a quick survey of the immediate area (about 20 meter radius), I observed this same activity at two other tree cavities simultaneously. Up to five females were perched outside the cavities, while one or two inspected the entrance. At one of the tree cavities, the females were very wary and during several hours of observation, I noticed that the gravid females entered and exited (after deposition) freely.

At two other cavities, there seemed to be a backup. Females would enter or partially enter, then quickly exit the hole. It wasn’t hard to deduce that something else was occupying the cavity. Even more interesting was that the females at these cavities were not wary, actually completely aloof to my presence. I was curious as to what was preventing their access, so I peered and blew air into one of the holes. As I did this, the females at the entrance which were looking at my face only inches away shifted their attention into the hole. I still couldn’t see anything, so I utilized a flashlight and after doing so, saw that a Croaking Gecko (Aristelligar praesignis) was “blocking” entry and appeared to defend the cavity from intruders. Additionally, I noticed the walls of the cavity encrusted with eggs. Considering the size and shape of eggs, all appeared to be freshly laid or previously hatched Anolis eggs.

I cannot explain the female anoles’ behavior and complete disregard of my presence; even allowing me to touch them (see video).

I had several hypotheses about this behavior; one is that perhaps females worked cooperatively to intimidate the cavity occupier (gecko) at entrance… even enlisting the observer as an ally?

After egg depsition

After egg depsition

Before egg deposition

Before egg deposition

Gecko in cavity (blurry), eye and eyestripe can be seen.

Gecko in cavity (blurry); eye and eyestripe can be seen.