Category: All Posts Page 23 of 149

Anolis gundlachi. Photo by Alejandro Sanchez.

A recent study published in Biotropica by Beard et al. (2020) examines the impact of removing anoles (Anolis gundlachi, specifically) and perhaps the Caribbean’s most iconic frog, the coquí (Eleutherodactylus coqui), on arthropod densities.

Lizard and frog removal increases spider abundance, but does not cascade to increase herbivory.

Beard, K. H., Durham, S. L., Willig, M. R., & Zimmerman, J. K.

Abstract:

Insectivorous vertebrates, especially on islands, can exert top-down control on herbivorous prey, which can transfer through a food chain to reduce herbivory. However, in many systems insectivorous vertebrates feed on more than one trophic level, especially consuming arthropod predators, and this intraguild predation can diminish trophic cascades. Our goal was to determine, using an exclosure experiment, the relative importance of anole lizards and coqui frogs in controlling spider and arthropod abundances as well as herbivory rates in the understory of the Luquillo Experimental Forest, Puerto Rico. We found that exclosures removing both anoles and coquis doubled spider abundance compared to exclosures with anoles and coquis at natural densities. The effect of coquis on spiders was greater and occurred more quickly than that of anoles, potentially because of the higher natural densities of coquis and removal of both vertebrates produced no interactive effects. We found support for the idea that anoles, but not coquis, reduce foliar arthropod abundances on one of the two studied plant species. However, there was also evidence that anole removal decreased herbivory, the opposite of what we would expect if there was a trophic cascade. Potential explanations include that anoles reduced predatory arthropods on foliage more than they reduced herbivorous arthropods. Results highlight that the food web in tabonuco forest is not simple and that there are complex and dynamic relationships among vertebrate insectivores, predatory arthropods, and herbivorous arthropods that do not consistently result in a trophic cascade.

Anolis bartschi. Photo by Shea Lambert

Anolis bartschi is one of the many spectacular anoles of Cuba. Hailing from a restricted area in western Cuba, little is known about this species (though see a previous Anole Annals dispatch).

A new paper just out in Phyllomedusa provides new diet data. Here’s some details:

Trophic ecology and morphology of Anolis bartschi  (Squamata: Dactyloidae) in Viñales National Park, Cuba

L. Yusnaviel García-Padrón, Geydis León Amador, Mariela Mezquía Delgado, and Yusvel Martínez Serrano

Abstract

Trophic ecology and morphology of Anolis bartschi (Squamata: Dactyloidae) in Parque Nacional Viñales, Cuba. Little is known about the trophic ecology of most anoles of Cuba. Morphology is directly related to ecological functions in lizards, such as feeding strategies, interspecific competition or energetic demands linked to reproduction. Anolis bartschi is a regionally endemic species, restricted to karstic hills of western Cuba. Here, we offer new insights into the trophic ecology of this species, and its relation to head morphology. We captured 131 adults; males were larger than females in size and head width. Most of them had prey in their stomachs. Males consumed more prey than females, but the latter consumed larger prey. Prey overlap within sexes was detected in the dry season, but trophic segregation occurred in the rainy season. Hymenoptera was the most frequently consumed prey in both sexes. In addition, females ate Blattodea and Coleoptera, and males consumed more Diptera. We suggest that this lizard prefers sedentary rather than mobile prey. According to our dataset and field observations, A. bartschi is a bimodal forager lizard, but research on temporal (daily and annual) variation in diet is recommended for a proper forage classification of this lizard.

Here is a short film I made concerning green and brown anoles in Florida and their behaviors and physical differences. Follow me on Instagram @dailyanole!

1st place: Two Anolis lineatus by Matthijs van den Burg.

Aryeh Miller and Ansley Petherick

Thank you once again to everyone who participated in this year’s Anole Annals photo contest! We received over 400 total votes from 14 different countries, and now we’re ready to announce the results. First up, the grand prize winner, is the above photo of two Anolis lineatus from Aruba taken by Matthijs van den Burg. The second place winner is below, Anolis polylepis from the Osa Peninsula of Costa Rica, by Anna Thonis. Congratulations!

2nd place: Anolis polylepis by Anna Thonis.

The rest of the winners are below, and their photos can be seen in the 2021 calendar here! Click the link to order your calendar.

Congrats again to all the winners, and happy holidays!

Anolis lineatus, Matthijs van den Burg

Anolis polylepis, Anna Thonis

Anolis evermanni, Anna Thonis

Anolis gundlachi, Anna Thonis

Anolis aquaticus, Lindsey Swierk

Anolis aquaticus, Lindsey Swierk

Anolis aquaticus, Lindsey Swierk

Anolis marmoratus, Kristin Winchell

Anolis princeps, Jhan Salazar

Anolis carolinensis, Delton Howard

Anolis sagrei, Delton Howard

Anolis oculatus, Charles Watson

Anolis roquet. Photo by Gaëll.

Read all about it in the latest issue of IRCF Reptiles & Amphibians.

Flicker is the bimonthly publication of the Cayman Islands Department of the Environment. The October issue, available here, reports on the introduction of the green anole, Anolis carolinensis, to Grand Cayman, and on continuing efforts to remove green iguanas from that same island. Older issues are also available. If you’d like to receive future issues, contact the editor.

Aryeh Miller and Ansley Petherick

The Finalists Are In!

Thanks to all who submitted photos for the Anole Annals calendar contest–we received lots of great submissions! We’ve narrowed it down to the top 32, and now it’s time for you to vote! Here’s a slideshow of the finalists:

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Vote Now!

Choose your 6 favorites in the poll below. You can right-click on the thumbnail to view full-size images in the poll, check the box next to your picks. You have 13 days to vote – poll closes on 12/13/20 (a Sunday) at 11:59pm. Spread the word!

Photo by Rachel Easton.

Periodically, we here at Anole Annals get reports of mating between green and brown anoles. Usually, it turns out to be a case of misidentification–often the “brown” anole is really a green anole in brown color phase, but sometimes it actually does happen. The most recent report comes from reader Rachel Easton, who tells the story of the picture above: “I’ve had them for a few weeks but they lived together at the pet store for months before I had them.  They are in a 20 gallon in my greenhouse. This is the first time I’ve witnessed the mating behavior. I moved their tank to another location and about 3 minutes later they were mating. I occasionally see them displaying their throats at one another but I assumed it was a territorial dispute over the best basking spot.”