All posts by Graham Reynolds

About Graham Reynolds

Graham is an Assistant Professor at the University of North Carolina Asheville. His research focuses on Caribbean herpetology- specifically anoles and boas.

Western North Carolina Green Anoles

Anolis carolinensis basking mid-winter in the Great Smoky Mountains National Park. Note the icicle in the left foreground. Photo by Sandy Echternacht from The Reptiles of Tennessee (UT Press 2013), and used with permission of the photographer and publisher.

Anolis carolinensis basking mid-winter in the Great Smoky Mountains National Park. Note the icicle in the left foreground. Photo by Sandy Echternacht from The Reptiles of Tennessee (UT Press 2013), and used with permission of the photographer and publisher.

Having recently moved to North Carolina, I am naturally inclined to get out and look for anoles. The state encompasses portions of the northern extent of the green anole (Anolis carolinensis) along the eastern seaboard, and a number of researchers are interested in both the evolutionary history of green anoles (Tollis et al. 2012, Campbell-Staton et al. 2012, Tollis and Boissinot 2014; Manthey et al. 2016) as well as, in particular, their ability to adapt to highly season regions (Jaffe et al. 2016). For a subtropical lizard to survive in areas that regularly see snow and ice is potentially an important study in regional adaptation. Indeed, this dramatic photograph below illustrates that anoles and icicles can coexist in both space and time.

This comes from work done by Sandy Echternacht and David Bishop at the University of Tennessee Knoxville. These researchers have shown that the green anoles in the Great Smoky Mountains National Park (yes, they occur there!) exist mostly on south-facing rocky slopes, and that they do not hibernate during the colder months. Instead, they will often bask on the rock faces when the sun shines directly on the rock (even when ambient temperatures are near freezing). During warmer months, the lizards move from overwintering sites into the forest, often along rivers (Bishop and Echternacht 2003, 2004). South of the Park, this species can be found in abundance along the banks of larger rivers.

North Carolina GAP Analysis Project

North Carolina GAP Analysis Project

In North Carolina, green anoles range up the Atlantic coast to Virginia, but have a more jagged latitudinal distribution moving west across the state. Known records (Palmer and Braswell 1995) decline in latitude as one approaches the city of Charlotte from the east, tapering to just barely north of the South Carolina border. Then, some curious incursions and apparently disjunct populations are recorded from west of the I-77 corridor (what generally constitutes Western North Carolina).

Anolis carolinensis from Chimney Rock, NC.

Anolis carolinensis from Chimney Rock, NC.

With one season under the belt, so to speak, my Herpetology class at the University of North Carolina Asheville and I have found what we think might be the closest population of green anoles to Asheville, North Carolina. This population occurs in a steep valley near Chimney Rock, North Carolina. Interestingly, they have access to steep south-facing rocky slopes above the valley. I thought I would poll the group and see if anyone has any hot tips on anole populations in the east Tennessee/Western North Carolina region. We are considering making this a Herpetology class project in the future- to map out the anole populations in this part of the state to see if they are in fact disjunct and whether any additional populations can be found. We will keep AA posted.

Anolis maynardi Male-Male Territorial Bout

This video was filmed and shared by Jen Moss of the Welch Lab at Mississippi State University. She observed the encounter near Preston Bay, Little Cayman, and it’s a great video showing this behavior. Lots of dewlaps, pushups, and potential exposure to predators owing to the use of a non-natural substrate. Thanks Jen!

 

Anole Surveys on the Cay Sal Bank, Bahamas

Alberto Puente-Rolon (Universidad Interamericana de Puerto Rico, Recinto de Arecibo) and I were incredibly fortunate to spend a week on the Cay Sal Bank, Bahamas. Cay Sal is a partially emergent island bank situated about 100 km south of Islamorada in the Florida Keys and about 50 km north of the Cuban Bank in the vicinity of Sagua la Grande. Politically part of the Commonwealth of the Bahamas, the bank is separated from the Great Bahama Bank by the 47 km-wide Santarem Channel, and is about 175 km west of the southern tip of Andros Island. Cay Sal Bank is a shallow carbonate platform with dozens of small emergent islands around the edges of the roughly triangular-shaped bank.

Anolis sagrei, Cay Sal Island. Photo by Alberto Puente-Rolon.

Anolis sagrei, Cay Sal Island. Photo by Alberto Puente-Rolon.

A note before we launch into the narrative of our trip. The Cay Sal Bank is an area known for a significant amount of illegal activity. This largely involves illegal fishing fleets and human trafficking. While a typical visitor to the area would not likely be in great danger from these activities, there is always the possibility that you might run into the wrong people at the wrong time. Illegal fishing vessels have been known to harass, intimidate, and attempt to board cruising vessels on Cay Sal, while happening upon a human or drug trafficking exchange could be extremely dangerous.  We saw evidence of all of these activities during our cruise, and mention some specifics in the narrative below. In addition, the Cay Sal Bank is remote. There are occasional Coast Guard planes in the area, but keep in mind that there might not be many vessels able to monitor emergency radio channels (channel 16) or respond quickly to an emergency. We cruised to the region with a highly experienced crew and a very well maintained and outfitted vessel, and we recommend anyone else planning to visit do the same, as well as consider taking all available safety precautions. I am happy to discuss my experiences in detail with researchers interested in visiting the area.

Anolis fairchildi, Cay Sal Island. Photo by RGR.

Anolis fairchildi, Cay Sal Island. Photo by RGR.

We arrived on the bank at dawn after an overnight cruise from Bimini, where we had cleared Bahamas customs and immigration. Our first stop was Dog Rocks, where we were able to disembark and swim ashore for a short walkabout on the largest of the small rocks jutting out of the ocean. The Dog Rocks mark the eastern edge of the Cay Sal Bank, and as far as we were aware there were no herpetofaunal records from these islands. Most are rocky and jagged, likely washed over during hurricanes and largely devoid of vegetation. Great Dog Rock is quite small, with a patchy covering of ground vegetation. There is a single large, pyramid shaped stand of Cocoloba uvifera near the center of the island-

Cocoloba uvifera stand on Dog Rocks. Photo by Alberto Puente-Rolon.

Cocoloba uvifera stand on Dog Rocks. Photo by Alberto Puente-Rolon.

approximately 5 meters high and 10 meters wide. Quite a few Sooty Terns (Onychoprion fuscatus) and Brown Noddies (Anous stolidus) nest here. Even in this very isolated and largely barren stretch of rocks, we managed to locate Anolis sagrei. The large males and robust females were mostly occupying the Cocoloba stand, though we did find juveniles, young males, and females on the ground near the scrub vegetation. We even located a juvenile underneath a discarded conch (Strombus gigas) shell. We spent about two hours here, plenty of time to survey the entire island. We did not find evidence of any other terrestrial reptiles, and it is quite remarkable that even A. sagrei could persist there.

Departure from Cay Sal Island. Photo by RGR.

Departure from Cay Sal Island. Photo by RGR.

Our next stop was at the Damas Cays, a small group of narrow, high-walled islets jutting out along the spine of the eastern Cay Sal Bank. Like Dog Rocks, we are unaware of any herpetofaunal records from Damas, and for good reason. We took a rigid inflatable boat out for a brief survey of the largest of the Damas Cays. There are no easy landing spots on the island, so landing would require a swim. There was very little vegetation, we spotted a single small shrub and some very sparse groundcover. As we approached the island to land, we lost power on our outboard engine and were losing daylight, so we opted to repair the engine and not to clamber ashore.

Cay Sal Island. Photo by RGR.

Cay Sal Island. Photo by RGR.

We then cruised across the bank to the southwestern edge, about 80 km from Cuba. Continue reading Anole Surveys on the Cay Sal Bank, Bahamas

Cayman Islands Anolis Research

Amy in the field working on her first noose capture.

Amy in the field working on her first noose capture.

The following was written by Amy Castle, an undergraduate and Summer Research Fellow in the Reynolds Lab at the University of North Carolina Asheville.

This past May, I had the opportunity to join Dr. Geneva and his team in the Cayman Islands to assist with his research on Anolis sagrei. Along with my mentor, Dr. Graham Reynolds, we were able to spend several days on both Little Cayman and Grand Cayman catching anoles, collecting data, and experiencing the tropics. This experience (my first in the tropics) provided me with an immersive education in both Caribbean herpetology and the ins and outs of working in the field. My adventure began when Dr. Reynolds and I flew to Grand Cayman and then took a small plane to Little Cayman, which is approximately 100 km northeast from Grand Cayman. Flying over these islands gave a good perspective of the topography and available habitat for the lizards. Most of the former island, which is only 16km long and 3 km wide, is lightly inhabited and dominated by tropical coastal coppice forest developed over a limestone base. On the ground, I quickly discovered that the anoles are everywhere!

Dr. Geneva’s research focuses on Anolis sagrei, in particular, the extent of variation in the species across its wide range. We were on Little Cayman to get data from this island as a component of a larger study, described in lots of previous AA posts (Eleuthera, Cayman Islands, Rum CayConcepcion IslandRagged IslandBiminiMangrove habitat, and Great Isaac Cay).

Little Cayman Anolis sagrei.

Little Cayman Anolis sagrei.

These beautiful brown anoles were abundant day and night on the island and could be frequently found at eye level on the trunks and branches of mangrove and seagrape trees. They have brightly colored red-orange dewlaps, short snouts, and a smaller body size, especially when compared to their sympatric congener Anolis maynardi. Anolis maynardi,  large green anoles native to Little Cayman, are often found higher in the trees and have green dewlaps with a yellowish tint.

 

Little Cayman Anolis maynardi.

Little Cayman Anolis maynardi.

During the few days we were on Little Cayman, the weather was really hot and humid. During the heat of the day, A. sagrei ventured deeper into the brush of the forest making it difficult to trudge through the trees without scaring them off. We were, however, able to capture them from several feet away by using an extendable fishing rod with a tied noose at the end. This was my first experience noosing lizards, but after a few tries, I was consistently able to catch individuals. At night, the anoles were much easier to capture. Using our lights and headlamps, we could simply pluck them off the leaves and branches where they were sleeping.

Grand Cayman Anolis conspersus.

Grand Cayman Anolis conspersus.

After finishing data collection on Little Cayman, we headed to Grand Cayman to obtain export permits. I had the opportunity to see much of the island, including the endemic Anolis conspersus. These beautiful anoles have a large degree of color variation across Grand Cayman, and we were able to see at least two of the major color morphs. I was also able to meet some great people (Jessica and Jane) at the Department of Environment, who mentioned that they were finding non-native anoles on Grand Cayman. This developed quickly into a project idea- one of my research projects so far this summer is examining the DNA of these unknown anoles to try to determine what species they actually are and where they came from. A little bit of forensic genetics!

Graham Reynolds and Amy on Little Cayman.

Graham Reynolds and Amy on Little Cayman.

This experience gave me an exclusive look into the world of Caribbean field herpetologists, and was really valuable as I am currently an undergraduate studying Ecology and Evolutionary Biology. I am particularly interested in the Cuban green anole clade, and my research with Dr. Reynolds focuses on Anolis fairchildi, an endemic species found on Cay Sal Island in the Bahamas. I am currently generating genetic data from this species and other members of the clade in order to examine the phylogenetic affinities of A. fairchildi relative to other Cuban green anoles. This trip gave me the opportunity to not only observe wild  A. maynardi, a relative of A. fairchildi, but also to understand the complex relationships between sympatric anole species. It is one thing to study anoles “at the bench” in Asheville, but being able to join Dr. Geneva and his team in the field has really sparked my understanding of, and interest in, these fascinating animals.

 

Carrot Rock and the Endemic Anolis ernestwilliamsi

Carrot Rock, a small protrusion of British Virgin Island, links the southern end of Peter Island to the edge of the shelf constituting the Puerto Rico Bank. This <1.3 hectare, steeply sloped island is home to two endemic squamate species: the Carrot Rock Skink (Mabuya macleani) and Ernest Williams’ anole (Anolis ernestwilliamsi). This is a somewhat surprising situation, given the proximity of Carrot Rock to Peter Island (400m) and its recent connection to the latter by a breaking shoal (water depths are but 2-3 m between the two). Hence, separation of Carrot Rock was likely recent, occurring as early as the end of the Wisconsin Glaciation (~8000 yrs ago) or at nearly any point more recently, likely within the last 3000 years (suggested by Mayer and Lazell 2000).

Carrot Rock, British Virgin Islands. This 1.3 hectare island is steeply sloped, with an elevation of ~25 m asl and a very steep aspect on all sides. There are no landing areas and the island must be reached by swimming. Obtaining a beachhead and summiting require exertion and great care.

Carrot Rock, British Virgin Islands. This 1.3 hectare island is steeply sloped, with an elevation of ~25 m asl and a very steep aspect on all sides. There are no landing areas and the island must be reached by swimming. Obtaining a beachhead and summiting require exertion and great care.

Nevertheless, morphological distinction has resulted in the specific epithets for these lizard species. The Carrot Rock Skink was described by frequent AA contributors Greg Mayer and Skip Lazell (Mayer and Lazell 2000) based on unique coloration and color pattern. The species was recognized in Blair Hedges and Caitlin Conn’s tome on West Indian skinks (Hedges and Conn 2012)–indeed, they used the node subtending M. macleani and other Virgin Island species as a calibration point. Recent analysis (Pinto-Sánchez et al. 2015) has suggested this species (along with other Virgin Island species), is (are) minimally divergent from the widespread M. sloanii complex. As the species was described based on morphology and appears to exhibit little genetic variation owing to a recent separation, species delimitation based on molecular data will surely point to collapsing these species and hence this latter finding is unsurprising.

Carrot rock is dominated by seagrape (Cocoloba uvifera) and the vine Stigmophyllon periplocifolium, with two large branching Pilosocereus royenii cacti on the crown. The majority of the anoles occur on the windward slope, where a few Cocoloba are sheltered enough to grow to heights of 1-3 meters.

Carrot rock is dominated by seagrape (Cocoloba uvifera) and the vine Stigmophyllon periplocifolium, with two large branching Pilosocereus royenii cacti on the crown. The majority of the anoles occur on the windward slope, where a few Cocoloba are sheltered enough to grow to heights of 1-3 meters.

Anolis ernestwilliamsi is very much a close relative of the widespread A. cristatellus. The endemic species is notable (and specifically recognized) largely for its increased lamellae number, color pattern, and apparently larger body size (Lazell 1983). It was described, again, by Skip, who is likely one of the few of us to have visited the island (and certainly the most frequent visitor). This description was published in Ernest Williams’ festschrift (Rhodin and Miyata 1983), in which, by my count, A. ernestwilliamsi is one of four nominate species named in honor of Ernest. As with the Carrot Rock Skink, molecular evidence suggests that A. ernestwilliamsi is minimally, or perhaps not at all, distinct from the widespread relative (A. cristatellus). Mitochondrial genetic analyses (Strickland et al., in review) demonstrate that A. ernestwilliamsi is nearly identical to many Puerto Rico Bank A. cristatellus haplotypes, suggesting a very recent maternal common ancestor (not surprising). Nuclear DNA has not yet, to my knowledge, been studied, likely owing to a lack of suitable (or available) DNA samples from the island. Concomitantly, several recent studies have demonstrated rapid evolution of key morphological traits in both Anolis sagrei (Stuart el al. 2014) and A. cristatellus (Winchell et al. 2016), including lamellae number, in response to presumed shifts in selection associated with either competitor species (Stuart et al. 2014) or non-natural substrate use (Winchell et al. 2016).

Female Anolis ernestwilliamsi. In a 1.5 hour survey around 1200h I counted fewer than 12 females.

Female Anolis ernestwilliamsi. In a 1.5 hour survey around 1200h, I counted fewer than 12 females.

Turning back to Carrot Rock itself, we might suspect that selection differs on this small island, and that selection would act rapidly in the face of the (presumably; Lazell 2005) small effective population size. This shifting of phenotype, owing to either plasticity or underlying allelic shifts, represents the processes of genetic drift and selection acting on a small population. This is an expected scenario, but leads to the question of how we like to recognize lizard species. As I teach my Zoology students, and as we all know, this is a tricky question. Anolis ernestwilliamsi is phenotypically distinguishable from other populations of A. cristatellus (Lazell, 1983). Some (myself included) might argue that this limited morphological distinctiveness is insufficiently diagnostic of speciation given the lack of genetic distinctiveness and the overall degree of morphological variation in the species. Nonetheless, some (Dmi’el et al., 1997) have examined whether the population of A. ernestwilliamsi is behaviorally and physiologically adapted to an arid and exposed habitat, implying an adaptive evolutionary response resulting in phenotypic evolution despite very recent separation and genetic similarity. That these authors found a similar physiological response (evaporative water loss rates) and that Carrot Rock is really not ecologically different from Peter Island (or most of the coastal portions of the BVI), further support the idea that the population is not terribly distinct.

Male Anolis ernestwilliamsi. In a 1.5 hour survey around 1200h I counted only 3 adult males.

Male Anolis ernestwilliamsi. In a 1.5 hour survey around 1200h, I counted only 3 adult males.

With all of this in mind, and having recently been to Carrot Rock, I remain skeptical regarding the prospects for continued recognition of A. ernestwilliamsi, despite the desire to see Ernest continue to have an Anolis namesake. Nevertheless, this should not (and indeed, didn’t/doesn’t) diminish the joy of seeing this population grasp tenaciously to existence on this speck of beautiful land.

 

 

References
Dmi’el et al., 1997. Biotropica 29:111-116.
Hedges, S.B. and C. Conn. 2012. Zootaxa 3288
Lazell, J. 1983. In: Rhodin and Miyata.
Lazell, J. 2005. Island: fact and Theory in Nature. University of California Press.
Mayer, G.C. and J. Lazell. 2000. Proceedings of the Biological Society of Washington 113:871-886.
Pinto-Sánchez N.R., et al. 2015. Molecular Phylogenetics and Evolution 93:188-211.
Rhodin, A.G.J. and K. Miyata. 1983. Museum of Comparative Zoology, Harvard University.
Stuart, Y.E., et al. 2014. Science 346:463-466.
Winchell, K.M., et al. 2016. Evolution 70:1009-1022.
[disclosure, I am an author on some of the papers mentioned in this article]

Conception Island, Bahamas Lizard Survey

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A view across Conception Island from the North.

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Female A. sagrei

As part of our saga chasing Anolis sagrei around the Caribbean, we had the incredible fortune to visit the remote Conception Island Bank in the Bahamas. Conception Island and its associated small satellites are situated on their own bank, adjacent to Long Island which occupies a southeastern edge of the Great Bahamas Bank. Conception Bank and all its satellite islets are protected by the Bahamas National Trust as a National Park, and the bank is presently uninhabited though there is some history of human habitation in the past. Conception Island is quite small, totaling only 9 km by 2 km and has never been connected to any other island banks, meaning that the plants and animals here have almost certainly arrived via dispersal. Though located only 25 km ENE from the northern tip of Long Island, the 2400 m deep water and strong NW currents mean that the Conception Bank has a relatively depauperate terrestrial fauna owing to the vicissitudes of over-water dispersal. For example, in the latest comprehensive list of island herpetofaunal records, Long Island boasts 16 native extant species of reptiles and amphibians, relative to just five on the Conception Bank. Granted, this is potentially owing to lower sampling effort on Conception, as it is a remote, difficult, and expensive place to conduct extensive surveys. Indeed at least one record, that of the Bahamas Boa Chilabothrus strigilatus, is poorly documented and probably spurious.

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An unusual dewlap color for A. sagrei

Alberto Puente-Rolon (UIPR-Arecibo), Anthony Geneva (Glor/Losos labs), Nick Herrmann (Losos Lab), and Kevin Aviles-Rodriguez (Kolbe/Revell labs) traveled with me to the Conception Bank aboard the Golden Bear out of Stella Maris, Long Island for two days in July 2015. Our goal was to sample Anolis sagrei from the bank, as well as generally conduct herpetofaunal surveys. We were particularly interested in verifying and attempting to build upon the last report of a herpetofaunal survey there (Franz and

Male Anolis sagrei displaying a light orange/ yellow dewlap in coastal palm scrub habitat.

Male Anolis sagrei displaying a light orange/ yellow dewlap in coastal palm scrub habitat.

Buckner 1998). While we expected Anolis sagrei to be present (it was), we also thought that the lack of a record for Anolis distichus might not stand up to our surveys. Alas, we checked multiple habitat types both day and night, from beach scrub to mature forests to mangroves and failed to turn up A. distichus. Though present on nearby Rum and San Salvador Banks (as well as Long Island), this species is curiously apparently absent from Conception.

Happily, we did find Anolis sagrei in abundance, and with some unusual features to boot. For one, the largest males are really quite large, tipping the scales at over 7 grams. Many males sported tall tail crests, and in the coastal scrub habitat, their yellowish dewlaps, combined with large size and tail crests, gave them an overall appearance very similar to Puerto Rican Crested Anoles (A. cristatellus). Interestingly, dewlaps in the forest appeared more traditionally sagrei-red, so we will see what our spectrometer and photographic data tell us about dewlap color variation on the bank. We will continue to update AA on our work with A. sagrei in the Bahamas.

Male Anolis sagrei with a large tail crest

Male Anolis sagrei with a large tail crest.

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Kevin and Nick at work

Ragged Island, Bahamas, Lizard Research

Air approach to Great Ragged Island

Air approach to Great Ragged Island

We have been on the move quite a bit for our project on Anolis sagrei. On a recent trip to the Bahamas, Alberto Puente-Rolon (UIPR-Arecibo) and I were able to visit the remote Great Ragged Island, located at the southeastern edge of the Great Bahamas Bank only 115 km from the coast of Cuba. Great Ragged is the only inhabited island in the Ragged Island/Jumentos Cays range, a necklace of islands stretching in a sweeping concave arc from Long Island and the southern Exumas to the range terminus at Little Ragged Island. A mere 70 or so people live on Great Ragged, concentrated in Duncan Town, a small settlement perched atop a surprisingly high hill overlooking the deep ocean to the east and dark green expanses of mangroves to the west. Duncan Town is picturesque in the authentic Bahamian sense–brightly colored houses are dotted between crumbling ruins dating back a century or more. Chickens cover yards, and old stone walls snake from the town out into the bush. An artisanal and on-demand salt raking operation continues here, and small pyramids of bleached salt dot the edges of an expansive salina filled with shallow waters reflecting varying hues of pinks and reds in the morning sunlight.

Duncan Town salina and tropical dry scub habitat

Duncan Town salina and tropical dry scrub habitat shallow waters reflecting varying hues of pinks and reds in the morning sunlight. Photo by Alberto Puente.

Anolis smaragdinus from Ragged Island

Anolis smaragdinus from Ragged Island. Photo by Alberto Puente

The Anolis sagrei here are, as in most locations, abundant. We had great success locating them at night, where they sleep exposed on branches and reflect a pale glow in the beam of a headlamp. We sampled anoles from different habitat types on Great Ragged, including coastal Cocoloba uvifera stands, mangrove forest, stunted closed canopy tropical dry forest (where we had to crawl to make our way through), and highly disturbed goat pasture. We are excited to see how the population here compares to the rest of the range. In particular, we are wondering whether the sagrei on Great Ragged belong to the eastern or western Bahamas genetic lineage, which we have uncovered in previous work. The A. distichus here certainly resemble the populations in the western Bahamas, rather than the eastern Bahamas, to which Great Ragged is connected by the Jumentos Cays. We will follow up on these distichus observations in a later post. I will keep AA updated on what we find as we begin analysis of our data.

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?

Great Isaac Cay

Approach to Great Isaac Cay. Note the Casuarina forest. Photo by Kristin Winchell.

Approach to Great Isaac Cay. Note the Casuarina forest. Photo by Kristin Winchell.

Great Isaac Cay, NE of the Bimini group, Bahamas. Image from Google Earth 2015.

Great Isaac Cay, NE of the Bimini group, Bahamas. Image from Google Earth 2015.

As Kristin mentioned in a previous post, we recently visited some of the Bimini islands  in search of data on Anolis sagrei ordinatus. Through a stroke of luck, we were able to visit remote Great Isaac Cay for an afternoon of herping, hoping to find some anoles there.

Great Isaac is a small weathered carbonate formation, rising perhaps 15m above the extreme northwestern corner of the shallow Great Bahama Bank. The island was more or less continuously inhabited for about a century by a lighthouse-keeper staff, and hence the native fauna could have been drastically affected. The island is frequently visited by boaters who come ashore to explore the ruins, as well as Bahamian commercial fisherman (note the boat in the right of the photo) who use the structures for shelter. The island now has a well developed Casuarina forest, with a deep (50-150cm) litter of Casuarina twigs.

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The author surveying the Casuarina forest on Great Isaac. Photo by Kristin Winchell.

We spent about six person-hours  around 1500h on Great Isaac- plenty of time to cover the entire island. We surveyed for reptiles by lifting and replacing loose rocks, as well as checking around and under vegetation and within abandoned structures. We failed to turn up a single anole, though we did find two species of reptiles. We encountered quite a few Sphaerodactylus nigropunctatus flavicauda under rocks in the Casuarina forest, and only two Ameiva auberi richmondi in open areas around the abandoned lighthouse.

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Surveying the west end of Great Isaac Cay. Photo by Kristin Winchell.

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Sphaerodactylus nigropunctatus flavicauda, female. Great Isaac Cay.

As far as we can tell there are no island lists of the herpetofauna for Great Isaac, indeed we did not even include the island in our recent list of Bahamian herpetofauna (available here). The island is at least listed in the original version of this work, yet without any records. So, has anyone else come across herpetofaunal records for Great Isaac Cay?

What’s the Best Camera for Photographing Lizards in the Field?

Hi Everyone, I am in the market for a new field camera. Looking for something durable, portable, and that can take great shots of anoles and their dewlaps (so good at close-ups, but not necessarily a macro lens). I currently use a Nikon D5100 SLR, but it is fairly bulky and fragile. What sorts of cameras and camera systems do you use in the field? Thanks!

Turks and Caicos Anole

This photo comes to us from Greg Braun, who found this exceptionally patterned juvenile anole during a recent visit to the Turks and Caicos Islands. It looks to me like a striking Anolis scriptus scriptus. I have previously reported on Southern Bahamas Anoles  (1,2,3) and always enjoy seeing pictures of this remarkable species. Enjoy!

Juvenile Anolis s. scriptus from the Turks and Caicos islands. Photo by Greg Braun.

Juvenile Anolis s. scriptus from the Turks and Caicos islands. Photo by Greg Braun.

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.

 

New Anole Distribution Records: Do Lizards in Potted Plants at Home Depot Constitute Range Extensions?

As mentioned in the previous post, the journal Herpetological Review is an excellent resource for anole natural history information. A frequent contribution is range extensions, often by county, for both native and introduced species. Range extensions are important pieces of information for biologists, as accurate county-level distributional data is crucial in many important exercises, such as mapping species richness in a region or identifying range boundaries (and then asking why the range ends in certain areas). This quarter’s issue has the following two range extensions.

Christopher Thawley and Fern Graves report a new county record for Anolis carolinensis in Bullock Co., Alabama, just south of Auburn. This apparently fills a hole in the confirmed range of the species in that part of Alabama.

Cory Adams and friends report an extension of Anolis sagrei range in Angelina Co., Texas. Interestingly, this specimen, as well as a specimen from Nacogdoches, Texas, were found in potted plants in Home Depot and Lowe’s garden departments. The authors posit that these animals turning up in East Texas are not range extensions, as in owing to the expansion of individuals from established ranges, but instead are the result of novel introductions facilitated by interstate transport of goods such as potted plants. If this is the case, these animals could have come from anywhere, not just the invasion front along the Gulf states. In other words, if the potted plants are coming from, say, Florida, then these animals would be leapfrogging their established conspecifics to potentially start new colonies and expand the range.

Adams, CK, D. Saenz, and JD Childress. 2014. Anolis sagrei (Brown Anole). Distribution. Herpetological Review 45: 282.

Thawley, CJ and F. Graves. 2014. Anolis carolinensis (Green Anole). Distribution. Herpteological Review 45: 282.

New Anole Behaviors in Herp Review: Brown Anole Steals Wasp from Spider, and Crested Anole Sleeps on Lampshade

The journal Herpetological Review, published by the society for the Study of Amphibians and Reptiles, frequently has interesting anecdotal reports of natural history observations of anoles. This quarter’s edition has two: nocturnal activity in Anolis cristatellus and prey stealing behavior in Anolis sagrei. Here is a synopsis:

Dean and Jennifer Metcalfe report on nocturnal behavior of A. cristatellus wileyae observed (while perhaps on vacation) at the Nanny Cay Resort and Marina on Tortola, British Virgin Islands. The authors observed that the subject anole had navigated the interior of their hotel room in near darkness after dusk, selecting a nocturnal perching site on a lampshade. They suggest that this is similar behavior to that of an anole selecting an arboreal perch site at dusk. Two questions come to mind though. First, whether the room was completely dark- as the authors acknowledge that some light might have been entering the room- and whether the animal came from the outside into the room to perch or was residing in the room. Second, the author mentioned that this was the only anole seen on Tortola during her brief stay, which is also a bit unusual as the species should be abundant there. This might not add much to our understanding of anoles, but it certainly raises some questions about the co-habitation of humans and anoles.

The second note comes from David Delaney, a master’s student in Dan Warner’s lab at UAB, and friends, who report on an opportunistic A. sagrei in Ormond Beach, Florida. The anole had apparently been observing a predation attempt of a spider-wasp on a funnel-web spider. To summarize, the wasp attacked and envenomed the spider, captured it, and began dragging it across the ground. At this point the anole jumped to the ground, grabbed the spider, and took it up the tree to eat it. The wasp, likely disappointed, fled the area to hunt again.

Metcalfe, DC and JE Metcalfe. 2014. Anolis cristatellus wileyae (Vrigin islands Crested Anole). Nocturnal Activity. Herpetological Review 45: 323-324.

Delaney, DM et al. 2014. Anolis sagrei (Brown Anole). Prey stealing behavior. Herpetological Review 45: 324-325.

Call for Assistance: Anolis sagrei

Hi Everyone, a quick post to see if anyone out there is interested in contributing to a large ongoing project on Anolis sagrei. We are sampling this species throughout the (mostly) native range, and currently have 77 sampling locations represented. However, we are wondering if anyone would be able to help us fill some remaining gaps.
We are interested in adding additional tissue samples from Central America and the Bahamas. Here is an approximate range map with some desired localities (in blue):

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Any help is greatly appreciated. I realize that collecting tissues (not to mention all the paperwork) is not a trivial task, so if you are interested in contributing samples please get in touch with me. We will keep AA posted on this project!

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.

 

 

 

cristatellus1

X Rays and Anoles

An exciting week in the Revell Lab, we received our order of 20 poles from Cabelas, and I picked up our new custom portable x-ray system in Newark yesterday.

The use of x-ray technology has been mentioned previously in AA- here, here , here, here, and here. The Losos Lab has used a similar portable x-ray system for the last several years with great success, and so we have obtained our own unit. One of the great advantages of these systems is that they allow researchers to gather highly detailed morphological data without harming the lizards and without using tedious methods such as dissection. The animals are simply anesthetized, imaged, and released after recovery. The Revell Lab has grand aspirations for our system- our graduate student Kristin Winchell plans to use it this summer in her studies of Anolis urban ecology. Continue reading X Rays and Anoles

A. cuvieri 2

Rare(ish) Puerto Rican Anoles

Another Revell Lab (Liam, Kristin, Graham) trip to Puerto Rico this spring, and another series of encounters with the diminutive Anolis occultus and the spectacular Anolis cuvieri. Both of these species can be quite challenging to find, but we have had some good success in several locations in the Puerto Rican karst region.  In January, we observed many individuals of both species

            

And managed to get a few in-hand for pictures

    

We also found a juvenile cuvieri, which has a gray coloration and an ontogenetic shift to green as they age:

Unless they happen to be one of the brown morph adults, Continue reading Rare(ish) Puerto Rican Anoles

Isla Bastimentos Anole

Panama Anole ID

A holiday quiz- can anyone ID this species? Found in the twilight zone of a cave in a small stream (hint) entering the main cave stream. Isla Bastimentos, Bocas del Toro Province, Panama. Apologies for the picture, one needs a good reason before hand to bring a nice camera into wet and muddy caves.

Has this species been reported from the BDT Archipelago?