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Anolis sagrei displaying in front of a supertree at the Gardens by the Bay

Two years ago, we posted on a paper in Nature in Singapore documenting the occurrence of the festive anole, Anolis sagrei, in Singapore. The ubiquitous colonizers had turned up in the newly created Gardens by the Bay, an enormous new botanical garden built on reclaimed land at the southern end of the island. AA decided to look into the situation further and sent this correspondent to the “Lion City” to report back on the situation.

Reporting for duty at the Gardens at approximately 930 am on the morning of 16 April, we quickly determined that the lizards are common in the lushly planted gardens pretty much wherever we went. The only exception was an open meadow housing a statue, where we did see an introduced agamid lizard (below). This area was only searched for three minutes, however, and it would not be surprising to find the anoles in the shrubbery surrounding the statue (below). The other place the lizards were not seen were in the two spectacular indoor cool houses, the Flower Dome and the Cloud Forest. Both are kept at temperatures possibly too low for the lizards, and also likely are fumigated.

Introduced Calotes versicolor at Gardens by the Bay

Otherwise, however, the anoles seem to be everywhere and it seems unlikely, given the luxuriance of the vegetation, that they can be eradicated (and we know how well such elimination efforts have fared in Taiwan—not).

The question is whether the anole will spread to the rest of Singapore, and from thence to Malaysia. Given the heavy motor traffic bringing visitors to the gardens, it seems inevitable that the anoles will hitch-hike their way across the bridge and colonize the main island of Singapore, which is for the most part one big Anolis sagrei habitat, with plenty of tropical vegetation everywhere. Moreover, the gift shop at the Gardens was selling orchids. I don’t know where they came from, but if on site, that is a great way to distribute brown anoles far and wide.

It’s not clear whether the anole is already present on the Singaporean main island. One commenter on our previous post said that it had been seen elsewhere, and I was told that there were unsubstantiated reports that it had been observed in the Singapore Botanical Garden. I spent several hours there myself and saw the anole mimic pictured on the right, but no anoles.

My prediction is that in ten years, Anolis sagrei will be very common in Singapore. But let’s see what the varanids, the Calotes and the birds have to say about that.

Meshaka and Layne have just published a masterful review of the native herps of southern Florida in Herpetological Conservation and Biology (freely downloadable). Of most interest to readers of these pages is the treatment of Anolis carolinensis, and it is indicative of the quality of this work: the six pages devoted to the natural history of the green anole is the most authoritative and comprehensive of which I’m aware, covering the literature for this species not only in southern Florida, but throughout its range. This monograph is the starting point for anyone interested in green anole biology. In addition, this section shows how surprisingly little we know about the biology of this species. For example, most of the information on green anole diet comes from Wayne King’s work from 1966.

This volume will be useful to anyone interested in the herpetology of southern Florida.

Photo by Janson Jones

Look at this poor fellow. Over on Phostracks, Janson Jones describes him and his demeanor thusly:

“Still, the most compelling characteristic of this anole was its passiveness. It wasn’t dead. Far from it, actually. The anole actively watched me, tracking me with its eyes. Still, when I rolled the lizard on its back, it just laid there like a puppy wanting a belly rub. Except for two or three miserable feeble attempts at escape, this anole was entirely passive (and clearly in need of a good dinner). It was just worn the hell out and in dire need of a vacation.

I placed the anole on the side of an unpopulated tree trunk to see if it could or would hang on (see image bottom left; image is rotated 90 degrees). No problem. It did just fine. It even moved around a bit. Then, when I started creeping back close again, nothing. It just sat there. Passive.

So, to quote Diondre Cole, “What’s up with that?” Any ideas? Any opinions? Any speculations?”

For more photos and entertaining description, check out the full post.

We’ve had posts on this spectacular anole before. Jesus Reina Carvajal reports: “During the last three years, I have been lucky to see them every single time I have visited the area but they are really hard to find. I find them in the wild on Cayo Santa María. They live exclusively on that island. Nowhere else in the world.

They eat insects, other lizards and small birds. They have a powerful bite. This last individual I could follow during hours since I saw it early in the morning and I could make many pictures and films until it left the place. That day I felt very happy!”

More of Jesus’s photos can be seen in the Flickr album he created.

Photo by Jesus Reina Carvajal

Photo by Jesus Reina Carvajal

This post is by Holly Brown, a grad student at UConn studying the visual ecology of wading birds.

The piscivorous brown anole

I spent the day filming herons at the Florida Keys Wild Bird Center, in Key Largo, FL. While changing positions to get a better view of interesting foraging behaviors of a juvenile Little Blue Heron and a Snowy Egret — head-tilting and foot-raking, respectively — I noticed a mad dash on the ground, ahead of the path I walked. I looked down, and a little anole had scrambled from the shoreline over to take cover in some mangrove roots, which were protruding out of the mud. I didn’t think much of this at first. I continued to walk along the shoreline, to follow a foraging white morph Great Blue Heron. I began to walk back toward the territory of the little anole, and noticed, yet again, a mad dash at ground level, from the shoreline into the mangrove roots. Thinking it might be odd to see an anole at the water’s edge I tried to find the well-camouflaged lizard amidst the vegetation. What I found was a lizard the size of an anole, but with a seemingly large, round head. Upon further examination, I realized that it was two heads–one anole head and one fish head! The anole had caught a minnow, and the poor little minnow’s head was sticking out of its mouth…gills still flapping and all.

Stroud and Beckles published this photo of a crested anole with a half-grey dewlap in the December 2014 issue of Herpetological Review. Cresteds dewlaps are usually orange or yellow–this is very unusual.

This is reminiscent of the famous gray-dewlapped A. carolinensis as well as this odd crested anole found by Neil Losin.

What’s up with these wacky anoles?

Congratulations to our friends at Tropical Herping for their photo in this month’s National Geographic.

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.

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.

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.

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

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?

Anolis sagrei with a regrown tail. Photo by Philip Fortman

Kristin Winchell has the answer. Check it out on her blog, Adaptability. Here’s a shot of the poster she discusses:

Compared with our extensive knowledge of male-male interactions, we know very little about how females interact with one another. Adding to a growing set of observations, here is some video (taken by my field assistant and seasoned anole videographer Jon Suh) of two bead-tagged female brown anoles mid-battle.

Both females are recent arrivals to this particular tree, and the lizard that remains on the tree at the end is marginally bigger than the one who leaves. Though I don’t think we witnessed the full interaction, I think it’s interesting that the females didn’t use their dewlaps in the course of this fight. This seems to match up with Ellee Cook’s description of a fight between two female A. gundlachi. The use of the dewlap by females has been observed during male-female interactions in A. cristatellus, A. armouri  and a few other species, but also during female-female interactions in some Central American anoles. Clearly we’ve got a long way to go before we characterize and understand agonistic encounters and display behaviour in female anoles!