All posts by James T. Stroud

About James T. Stroud

Evolutionary ecology PhD student working in Miami FL interested in Anolis coexistence and community assembly: www.jamesTstroud.com

Evolution 2017: It Doesn’t Pay to Be Risky When Predators Are About

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Oriol Lapiedra opened up the penultimate day of Evolution by discussing his results of a recent field experiment in the Bahamas. In this project, Lapiedra and colleagues evaluated how inter-individual variation in behavior – specifically risk-taking – influenced survival. To do this, the research team took advantage of a well-understood model system in evolutionary ecology: brown anoles (Anolis sagrei) on islands with and without anole-predators (curly-tailed lizards; Leiocephalus carinatus) in the Bahamas. Male and female brown anoles were collected and subjected to a behavioural trial which measured the amount of time it took for a lizard to leave a refuge after being exposed to a predator. These observations were used to quantify each individual’s propensity to take risks. For example, those individuals that left their refuge shortly after seeing a predator were interpreted as being more ‘risky’ than more conservative individuals. Following these trials, each lizard was x-rayed to assess morphology and individually tagged, before being released onto one of 4 predator-free islands or 4 predator-present islands, all of which were currently void of anoles.

Lapiedra et al. started with a priori hypotheses that overall survival would be lower on those islands with predators, and those that did survive would be individuals considered less risky. After waiting 4 months, the research team returned to the Bahamas to collect all lizards from each island and see which individuals had survived. The authors report that, as expected, overall survival was lower on islands with predators, and that there was a significant relationship between behaviour and survival such that high risk-taking individuals had much lower survival when predators were present. This suggests that under those biotic conditions, natural selection operates against those riskier phenotypes. On closer inspection, this relationship was largely driven by a strong relationship in females, with no significant relationship existing between risk-taking behavior and survival of males.

Lapiedra et al. then contrasted these results by independently assessing how morphology was related to survival. The authors found that both risk-taking behavior and morphology influenced survival, however – and, important to this study – the relative effect of an individual’s risk-taking behaviour was much more influential on survival.

Lizards On The Loose: Middle School Students Help Track Invasive Anoles in Miami, FL

As you have heard before on Anole Annals, the Lizards On The Loose project involves middle school students conducting anole surveys in their back yards, school grounds, and local parks throughout South Florida. You can read more about the background and early results of this project in an earlier AA post which summarizes my talk at the Ecological Society of America’s (ESA) 2016 annual meeting.

Well, now we have updated results! Chris Thawley, a postdoc in Jason Kolbe’s lab and new member of the Lizards On The Loose team, has produced this video which explains what we have learned from the new data collected by students during their 2016-17 surveys. One species that we are particularly interested in is the Puerto Rican crested anole (Anolis cristatellus), whose distribution in Miami has been closely monitored since their introduction in the 1970s (see Kolbe et al. 2016 for a review of this species’ range dynamics in Miami). To our amazement, middle school students identified populations of crested anoles that were brand new to us! Watch below for more information:

Box Turtle Scavenges Green Anole!

My good friend Trace Hardin, a professional entomologist but also avid herper and snake breeder, just sent me these photos below. Here’s what he had to say about the encounter on Instagram:

hardinherpetologica: Interesting observation while walking through the woods. Found this #BoxTurtle eating a dead #GreenAnole. I’m assuming it was a scavenged find but the entire body was gone by the time I came upon the scene. #Neature

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Has anyone else observed box turtles (or any other chelonian [I guess now testudine?]) interacting with anoles?

Predation of a Gecko by Anolis pulchellus in the British Virgin Islands

In the most recent issue of Herp Review, Anole Annals stalwarts Kevin de Queiroz and Jonathan Losos documented their account of observing an adult female grass-bush anole (Anolis pulchellus) consume a dwarf gecko (Sphaerodactylus macrolepis) on Guana Island, British Virgin Islands. The authors share their detailed report below:

Many primarily insectivorous lizards will eat other vertebrates on occasion, a behavior that has been reported in many species of Anolis. One unifying generality is that such carnivory is size structured, with the predator usually being substantially larger than the prey (Gerber 1999. In Losos and Leal [eds.], Anolis Newsletter V, pp. 28–39. Washington University, Saint Louis, Missouri). Not surprisingly, reports of anole carnivory pertain primarily to middle-sized and larger anoles. Here we report carnivory by a small anole of the species A. pulchellus. To our knowledge, this is the first instance of carnivory reported for this species and one of few for any similar-sized anole (the record noted by Henderson and Powell 2009. Natural History of West Indian Reptiles and Amphibians. University Press of Florida, Gainesville, Florida. 495 pp. is based on the observations reported here).

Fig. 1. Female Anolis pulchellus in the process of ingesting a Sphaerodactylus macrolepis.

Fig. 1. Female Anolis pulchellus in the process of ingesting a
Sphaerodactylus macrolepis.

We observed a female A. pulchellus (SVL ca. 38 mm) capture and consume a Sphaerodactylus macrolepis (SVL ca.18 mm) in the leaf litter at approximately 1430 h on 25 September 2006, on Guana Island, British Virgin Islands, near the head of the Liao Wei Ping Trail at roughly 18.47916°N, 64.57444°W (WGS 84). The anole jumped from a low perch (ca. 20 cm above the ground) to the ground and bit the gecko, which escaped and fled 15–20 cm to the opening of an ant nest. The anole attacked the gecko again, seized it in its mouth and carried it approximately 10 cm up a vine, a distance of 15–20 cm from the site of attack. Initially, the anole held the gecko upside down (i.e., dorsal surface facing down), biting it between the fore and hind limbs on the left side. Eventually the anole worked its grasp posterior to the base of the tail, still on the left side. At this point, parts of both the base of the tail and the left hind limb were in the anole’s mouth (Fig. 1). The anole then manipulated the gecko so that it was no longer upside down, but rotated about its long axis by roughly 90 degrees (the ventral surface of the gecko was then oriented forward relative to the anole) at which point it was biting the gecko at the base of the tail and possibly by the left hind limb; the anole eventually manipulated the gecko so that it held it tail-first in its mouth, dorsal side up, at which point the anole proceeded to ingest the gecko tail first (during this time, the tail itself broke off and was carried away by ants, which had been biting the gecko in several places since shortly after it was
captured by the anole). Total time from capture to complete ingestion was approximately five minutes.

Predation on Sphaerodactylus geckos has been reported in anoles of only a few species, none of which are as small as Anolis pulchellus (Henderson and Powell 2009. Natural History of West Indian Reptiles and Amphibians. University Press of Florida, Gainesville, Florida. 495 pp.). However, given the size discrepancy between the lizards in these two clades and their extensive coexistence across the Caribbean, we suspect that such interactions may occur with some frequency. Moreover, the high population densities of some Sphaerodactylus geckos (e.g., Rodda et al. 2001. J. Trop. Ecol. 17:331–338) and the diurnal activity of several species (Allen and Powell 2014. Herpetol. Conserv. Biol. 9:590–600) suggest that they may be important prey items for anoles.

References
Allen, K.E. and Powell, R., 2014. Thermal biology and microhabitat use in Puerto Rican eyespot geckos (Sphaerodactylus macrolepis macrolepis). Herpetological Conservation and Biology, 9(3), pp.590-600.
Gerber 1999. In Losos and Leal [eds.], Anolis Newsletter V, pp. 28–39. Washington University, Saint Louis, Missouri
Henderson and Powell 2009. Natural History of West Indian Reptiles and Amphibians. University Press of Florida, Gainesville, Florida. 495 pp.
Rodda, G.H., Perry, G.A.D., Rondeau, R.J. and Lazell, J., 2001. The densest terrestrial vertebrate. Journal of Tropical Ecology, 17(02), pp.331-338.

Early Breeding Season Injuries through Aggressive Interactions in Miami, FL

It’s currently dewlapping mayhem down here at the moment, with all species except the late-rising Cuban knight anoles (A. equestris) out and showing off!

IMG_9836 (2) An adult male Puerto Rican crested anole (A. cristatellus) performing dewlap extension displays in Miami FL

Visual displays such as dewlap extensions are often used to mediate physical interactions by acting as an indication of the relative size, strength, and fitness of each individual. This is beneficial for both parties; dominant individuals do not have to waste energy that a physical interaction would require, and weaker individuals avert the risk of physical injury (of course, both reasons are reciprocal to both individuals also).

However, when two individuals cannot determine dominance through visual communication, for example if two individuals are equally matched in size, then an aggressive and physical confrontation may occur (read a previous account of one such interaction between two equally-sized males here). The results of these interactions are apparent in many injurious forms, for example through extensive bite marks to the body (as previously discussed here and here), or perhaps even to the extent of tail loss (as discussed here).

Yesterday (9 March 2017) I observed this male Puerto Rican crested anole (A. cristatellus) below that looks like another male had taken a good bite at him!

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Of course, there are many avenues through which such an injury may appear. However, the presence of a still-erect nuchal crest paired with how fresh the wound looks (and the time of year!) gives me the impression that this was probably the result of an intraspecific male-male interaction.

Ecology of the San Salvador Bark Anole (Anolis distichus ocior)

 An adult male San Salvador Bark Anole (Anolis distichus ocior) displaying. Photograph by Guillermo G. Zuniga.

An adult male San Salvador Bark Anole (Anolis distichus ocior) displaying.
Photograph by Guillermo G. Zuniga.

Dayton Antley and colleagues from Avila University, the home of AA stalwart Bob Powell, recently published a detailed study of the ecology of the San Salvador bark anole (Anolis distichus ocior) in IRCF Reptiles & Amphibians (an open-access herpetological journal, with this article available here). Anolis d. ocior is one of 17 recognized subspecies of the diverse distichus group, and is found on only San Salvador and Rum Cay (Henderson and Powell 2009).

Antley et al. assessed microhabitat use, activity patterns, and approach distances of A. d. ocior in an approximately 0.3ha study area on the grounds of the Gerace Research Centre, dominated by Tropical Almonds (Terminalia catappa), Papaya (Carica papaya), and Ficus trees.

A Google Map view of the Gerace Research Centre. The study site (24°07'05.2"N 74°27'50.9"W) is outlined in white.

A Google Map view of the Gerace Research Centre. The study site
(24°07’05.2″N 74°27’50.9″W) is outlined in white.

In assessing patterns of microhabitat use throughout the day, Antley et al. conducted surveys every two hours for two days from 0700h (about 40 min after sunrise) to 1900h (about 40 min before sunset). Size class, perch height and diameter, body orientation relative to the ground, and thermal microsite (sun/shade/mixed) were recorded for every observed lizard. In the following two days, approach distances were assessed. This was achieved by a surveyor, wearing neutrally-coloured clothing, approaching an undisturbed anole at a steady pace and recording the distance at which the lizard reacted. Over two additional days, 10-minute focal animal observations were conducted of individual adult lizards (including both males and females) at a distance of 5m. The number of movements (changes in location or orientation), head turns, and head bobs were recorded for all lizards, with dewlap displays and pushups being additional recorded for males.

Lizards were active throughout the day, with activity peaking in the early morning and before midday. This was compared to ambient air temperatures recorded 1m from the ground in a shaded and sheltered location. This result surprised the authors, as a second activity peak in late afternoon/early evening was expected, as has observed in other similar studies of bark anoles (e.g. Hillbrand et al. 2011).

Mean number of lizards active (bars) and mean ambient temperatures (dots) per time period. Temperature data were collected on two consecutive days.

Mean number of lizards active (bars) and mean ambient temperatures
(dots) per time period. Temperature data were collected on
two consecutive days.

Adult males experienced highest levels of arboreality during the middle of the day, while subadult males and adult females (grouped together as they can be hard to distinguish from distance) were highly variable (see figure below). Most lizards of all classes were found in the shade, which the authors attributed as evidence for thermal conformity, and facing downward towards the ground, a common trait in many anoles that is most commonly perceived to increase an individual’s ability to monitor potential predators, competitors, or mates. 43% of lizards, however, were observed facing upwards. The author’s note that this behavior is often interpreted as an individual prepared for escape; however as all lizards were observed from distance and undisturbed, they (admirably) explain that this result is difficult to interpret.

A: Mean perch heights (cm) of adult males (L) and subadult males and females (S); B: mean perch heights of adult males at different times of day; C: mean perch heights of subadult males and females at different times of day.

A: Mean perch heights (cm) of adult males (L) and subadult males and females (S); B: mean perch heights of adult males at different times of day;
C: mean perch heights of subadult males and females at different times of day.

Adult male lizards were bolder than smaller subadult males and females, and retreated at a much closer distance when approached by a surveyor (0.99m +/- 0.07m vs. 1.54m +/- 0.18m). Focal observations revealed no significant differences between adult males vs. subadult males/females in shared behaviors, although there was a high variation in the amount of displaying behavior between adult males. The average time spent conducting dewlap displays was 3%, although one male was recorded investing 47% of his time in a combination of dewlap extensions and pushup displays.

Using all survey data combined, Antley et al. estimate that A. d. ocior in this study plot had a population density of 593 individuals/ha, with lizards observed on all but four of the smallest trees surveyed. Antley et al. note that their density estimate is extremely conservative, and much lower than previously published estimates (e.g. 1.070-5,460 individuals/ha, Schoener and Schoener 1978). The authors suggest that the small size of the study plot may have contributed to the relatively low density.

In all, this is a charming (although admittedly short) study of the natural history of the San Salvador bark anole (A. d. ocior) – a great example of an undergraduate research project that follows through to publication!

References
– Antley, D.L. et al. 2016. Microhabitat, Activity, and Approach Distances of the San Salvador Bark Anole (Anolis distichus ocior). IRCF Reptiles & Amphibians 23(2): 75-81
– Henderson, R.W. and R. Powell. 2009. Natural History of West Indian Reptiles and Amphibians. University of Florida Press, Gainesville, Florida.
– Hillbrand, P.A., A.T. Sloan, and W.K. Hayes. 2011. The terrestrial reptiles of San Salvador Island, Bahamas. Reptiles & Amphibians 18: 154–166.
– Schoener, T.W. and A. Schoener. 1978. Estimating and interpreting body-size growth in some Anolis lizards. Copeia 1978: 390–405.

ESA 2016: Top-Down Effects of Brown Anoles on Islands Following Hurricanes

Following up with summaries of anole talks at ESA 2016, Dave Spiller presented a broad summary of his and his colleague’s (Tom Schoener and Jonah Piovia-Scott) research investigating the effects of hurricanes on long term food web dynamics of small Bahamian islands, which has just recently been published in Ecology (see Spiller et al. 2016).

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Spiller opened by explaining some of the patterns of food web dynamics that have been learned from this research. Most notably, that the elimination of brown anoles – which act as top predators in these simple ecosystems – leads to increased levels of herbivory as arthropods experience a relaxation of predation pressure (Spiller and Schoener 1990).Specifically, the presence of a common moth (Achyra rantalis) on islands without brown anoles can lead to extreme levels of herbivory upon a common island plant, Sesuvium portulacastrum (below).

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Spiller and his colleagues began to notice that following hurricanes, one of the most extreme natural disturbance events in this region, islands with lizards experienced a much more rapid recovery of Sesuvium .

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In an attempt to understand how ecosystems may be stable despite experiencing extreme disturbance regimes, Spiller and colleagues measured the percent ground cover of Sesuvium and abundance of Achyra moths on 11 islands with lizards present and 21 islands without lizards annually for 10 years.

Overall abundance of Achyra was 4.6 times higher on no-lizard islands than on lizard islands. The percent cover of Sesuvium exhibited lower temporal variability on lizard islands when the study site was undisturbed by hurricanes, and higher recovery rate on lizard islands following hurricanes.

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Spiller concluded by suggesting that these stabilizing phenomena are linked to a trophic cascade in which predators (brown anoles) control herbivores (Achyra moths), and therefore enhance plant recovery following hurricanes.

ESA 2016: Niche Partitioning and Rapid Adaptation of Urban Anoles

Maintaining an already-impressive 2016 conference tour de force which included presentations at both JMIH and Evolution, Kristin Winchell presented a broad summary of her urban anole research in an invite-only Urban Ecology session at ESA 2016.

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This presentation provided a synthesis of two large research projects both independently reviewed on Anole Annals (1,2), and so I will provide only a brief summary here. Kristin began by presenting an over-arching question in modern ecology: how is urbanisation going to affect biodiversity? While many may intuitively think of the process negatively, there is a large (and growing) body of research suggesting that many species are able to behaviourally respond to these novel environments and persist. So what about anoles? Kristin focuses her research on two Puerto Rican species: the crested anole (Anolis cristatellus) and the barred anole (A. stratulus).

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To do this, Kristin and her team employed multiple methods to explore if a) these two species have differences in their ecology in urban vs. natural areas, b) if differences in ecology are observed, does this lead to differences in morphology, and c) if differences in morphology are observed, is this related to performance? Firstly, niche partitioning between these two species in natural vs. urban areas was investigated (more details here).

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This niche partitioning research is new and will be the main body of a manuscript currently in prep so I will keep discussions brief. One species, A. cristatellus, was observed to significantly shift its microhabitat use, which resulted in adaptive shifts in morphology. This research was documented in Winchell et al.’s recent Evolution paper and reviewed previously on AA (1,2,3). Specifically, urban lizards have longer limbs and stickier toepads (higher number of subdigital lamellae) in response to perching on broader, slippier substrates.

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This research has now developed on to the next stage of performance-related investigations. Kristin is asking the question of whether these observed morphological shifts lead to better performance (and therefore, presumably, higher fitness). Kristin presented some preliminary results, but keep your eye out for more developments!

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JMIH 2016: Variation and Distribution of Anolis roosevelti

One of the few known Anolis roosevelti specimens.

One of the few known Anolis roosevelti specimens.

Anole stalwart Greg Mayer gave a wonderful talk discussing the distribution and morphology of the large and maybe-extinct Anolis roosevelti. A. roosevelti, commonly known as the Culebra Island giant anole, was first described in 1931 by Chapman Grant, a US Army Major and practising herpetologist, from a single adult male specimen collected on Culebra. Although Reinhardt and Lutken, in 1863, had already provided an accurate description of A. roosevelti, but under an alternative name of A. velifer.

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Reinhardt and Lutken’s specimens were collected from Vieques, Tortola, and St. John, although Greg having the opportunity to study them meant tracking them down to natural history collections in both Copenhagen and Stockholm. In total, this entire species is known from eight specimens, only six of which are still in existence (Greg had the opportunity to study all six, meaning he’s now seen more roosevelti than any other anolologist?). Greg explains that roosevelti based on the limited information provided by Dimas Villanueva, who collected the holotype, and his own investigations, roosevelti can be classified as a “crown-giant” ecomorph. This means that the eastern islands of the Puerto Rico bank had a series of four ecomorphs, with roosevelti being what Ernest Williams termed a climatic vicariant of cuvieri, occuring in (and presumably being adapted to) the more xerophytic forests of the eastern bank islands.

The known distribution of Anolis roosevelti.

The known distribution of Anolis roosevelti.

Greg went on to describe the morphological features which distinguish A. roosevelti from a A. cuivieri, an ecologically and morphologically similar species from neighbouring Puerto Rico. Roosevelti is a larger, brownish gray rather than green as is seen in cuvieri (although check out these gray cuvieri preveiously mentioned on AA). Roosevelti generally has larger head scales, and a more elongate and deeply grooved head – these differences are confirmed in the ANCOVA analyses below.

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So, what chances are there of seeing roosevelti in the wild? Low, probably. No specimens have been collected since 1932, and several researchers, including Greg, have recently scoured both Vieques, St. John and Tortola but with no success. By far the most extensive searches have been conducted by Ava Gaa, who exhaustively searched Culebra (totalling 1500 hours of looking!) as well as short visits to Vieques and St. John all with no success. Tantalising reports of potential candidates turned out to be juvenile green iguanas. Greg concludes by recommending that the long-protected and relatively poorly explored eastern half of Vieques may hold the secret to if any populations remain.

Dewlap Displays in Cuban Knight Anoles (A. equestris)

While exploring the grounds of Fairchild Tropical Botanical Gardens with Janson Jones this past weekend, we extremely fortunately happened upon a large adult male Cuban knight anole (A. equestris) in full displaying swing. Despite the fact that knight anoles have an impressively large dewlap, I have often found this to be a relatively rare event, as large crown-giant species tend to display less than other smaller and more active species. This individual was displaying at a height of ~15 m, just below the fronds of a large Royal Palm (Roystonea regia). We didn’t see any other neighboring knight anoles, so were unsure if this was a directed or passive display series. In all, this lizard performed perhaps 4-5 sets of dewlap displays (each comprising of 4-5 dewlap extensions) before stopping and retreating back into the canopy.

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Anoles typically follow a predictable and repeated pattern of display that gradually increases in intensity. Initially, and rather lethargically, an individual will nonchalantly raise its head and extend its dewlap without much extra effort (stage a); described below from Losos (2009).

Adapted from Losos (2009), which itself is adapted from Losos (1985). Aggressive behavior of A. marconoi showing three stages of increasing display intensity - note stage (c) include full body elevation alongside simultaneous tail and dewlap extensions.

Adapted from Losos (2009), which itself is adapted from Losos (1985). Aggressive behavior of A. marconoi showing three stages of increasing display intensity – note stage (c) include full body elevation alongside simultaneous tail and dewlap extensions.

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This then escalates to include a slight body raise (stage b).

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And ultimately results in a dramatic finale – in full display all limbs will be extended to raise both their body from the substrate (in this case the trunk of a palm tree) and elevate their tail (stage c). In the following picture you can see this final stage of displaying where intensity peaks – albeit in this individual with a regenerated (and rather stubby) tail. Continue reading Dewlap Displays in Cuban Knight Anoles (A. equestris)

Cuban Knight Anole (A. equestris) with a Hole in Its Dewlap

While doing some local herping for fun this weekend with a couple of friends visiting from out of town (Janson Jones of previous AA fame; 1,2,3,4,5), we happened upon this Cuban knight anole (Anolis equestris) with a fairly conspicuous hole in its dewlap. Despite this, the lizard appeared in prime condition. Other reports of strange dewlaps have been documented on AA before, such as these grey-dewlapped Puerto Rican crested anoles (A. cristatellus) and American green anoles (A. carolinensis), but has anyone ever seen any individuals with tissue missing from the core region of the dewlap (as opposed to injuries sustained on the peripheries, such as this Cuban brown anole (A. sagrei), which aren’t generally that uncommon)?

Here’s one example, from an AA post from four years ago.

 

Crested Anole (A. cristatellus) Predation by a Tricolored Heron (Egretta tricolor) in Miami, FL

On a fleeting one-night stopover in Miami last week, Anthony Geneva had the chance to pop in and say hello at Fairchild Tropical Botanical Gardens and take a morning stroll to view some of the resident anoles (see others posts about Fairchild anoles here: 1,2,3,4). While waiting to be joined by fellow local anolologist and distichus aficionado Winter Beckles (University of Miami), Anthony and I noticed some commotion by the edge of a nearby pond. Upon closer inspection, we realized that a tricolored heron (Egretta tricolor) appeared to be juggling a large anole in it’s mouth! In my morning rush, I had managed to forget not just my anole-catching noose pole, but alas, also my camera. Fortunately, Anthony was on hand to fill the David Bailey role.

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After re-positioning the lizard a few times, the heron appeared to do something peculiar – it repeatedly dunked the lizard in and out of the water. This happened perhaps 5-6 times. Was this an attempt to expedite a fatality prior to consumption, or perhaps a neat trick to help lubricate such a large prey item?

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In all, the process of ingestion took less than 10 seconds, following a couple of minutes of dunking and repositioning.

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This observation follows a recent hot post reporting the predation of anoles by reintroduced whooping cranes (Grus americana) in Louisiana, which itself was preceded by various observations of avian-fuelled anolivory in South Florida (1, 2, 3, 4). Even more recently, while showing Thom Sanger and Bonnie Kircher around Fairchild Gardens a few weeks back, we observed a Cooper’s hawk (Accipiter cooperii), a widely-regarded bird specialist, snatch an American green anole (A. carolinensis) from the frond of a towering Royal Palm (Roystonea regia) – an event Rob Heathcote and I had observed the previous year with an adult male A. cristatellus in nearby Matheson Hammock. Unfortunately none of us were privileged with Anthony’s camera reflexes to capture any of those events.

So, why’s this interesting? (Excluding the obvious natural history enlightenment of revealing, at least personally, a previously unclear predator-prey interaction). Well, tricolored herons are a widespread breeding resident throughout much of the US Gulf states and as far south through the Caribbean to central Brazil and Peru. Therefore, the consumption of crested anoles (A. cristatellus) isn’t necessarily a novel interspecific interaction – it’s possible that this occurs in the native range of A. cristatellus, Puerto Rico, where both exist. However, although tricolored herons are natural residents of South Florida, it would be a tough sell to argue that crested anoles would be naturally on the menu. Crested anoles were first introduced to South Miami in the 1970s – the original site of introduction being a mere stone’s throw from this observation (for a review of the subsequent dispersal patterns of A. cristatellus in Miami see Kolbe et al. 2016; pdf here). So although crested anoles are being exposed to many novel biotic interactions in Miami, it seems they can’t escape some.

Have any Puerto Rico anolophiles observed this interaction before?

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A smug bird.

Brown Anole Predation by Red-bellied Woodpeckers in Florida

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While visiting relatives last week in Fort Myers (FL), anole enthusiast and avid wildlife photographer Kyle Wullschleger noticed a commotion among the trees while on an afternoon hike in a small neighbourhood nature preserve. On closer inspection he witnessed a group of red-bellied woodpeckers (Melanerpes carolinus) foraging on surrounding cypress trees, with a couple eventually appearing with their apparent target–non-native Cuban brown anoles (A. sagrei). He recalls some of the details:

“The photos from the sequence aren’t all that fantastic because I cropped in so it really just shows the behavior. The whole sequence the woodpecker was basically just slamming the anole against the tree and then trying to pick it apart – it was hard to tell what exactly it was doing, but I believe it eventually swallowed it whole before flying away–it hopped behind the tree so I couldn’t see it anymore.”

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“There were at least five birds all moving up and down the lower third of the cypress trees just around the boardwalk I was on. They were moving around the trees without really knocking the wood, so maybe they were purposefully targeting anoles? I only saw successful predation twice, but the brush is so thick–it’s obviously happening quite a bit.”

Sean Giery had previously discussed the main avian predators of anoles in urban South Florida, but woodpeckers didn’t make the list. Woodpeckers do occur in urban areas of South Florida; a new one to add to the list?

On the importance of Dorsal and Tail Crest Illumination in Anolis Signals

With a flurry of recent attention investigating how background light may influence the signalling efficiency of Anolis dewlaps (1,2,3,4), particularly those inhabiting low-light environments where patches of sunlight appear at a premium, it occurred to me that extended dorsal and tail crests may fall under similar selection. Below are some photos of Puerto Rican crested anoles (Anolis cristatellus) – a species in which males exhibit an enlarged tail crest and the ability to voluntarily erect impressive nuchal and dorsal crests during aggressive interactions (the mechanisms of which are detailed in this previous AA post) – that show how crests may contribute to signalling.

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I have no doubt this thought has crossed the minds of many anole scientists before, particularly those current graduate students so successfully studying A. cristatellus and familiar with their ecology and behaviour (namely Alex Gunderson, Kristin Winchell, Matt McElroy, and Luisa Otero). Dewlaps are undoubtedly of primary importance to anole signalling and communication, but what are people’s general thoughts on the relative importance of other morphological features?

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Brown Anole (A. sagrei) Surveys in Orange County, CA

Louis Shanghan of the LA Times reports on Greg Pauly‘s field surveys of non-native Cuban brown anoles (Anolis sagrei) and geckos in Orange County neighborhoods

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“The anoles, which are native to Cuba, arrived here about a decade ago as stowaways in nursery plants,” Pauly said as the team strode down a leafy street, methodically scanning sidewalks, brick walls and tree trunks for the stick-like shapes of lizards basking in the sun. “Today, there’s at least 10 to 20 per residential lot in this neighborhood alone.”

“There’s a nice one over there,” he said, nodding toward an anole – about five inches long, adorned with light brown speckles and a bright line running from head to tail – clinging to the side of a front-yard planter box.

Full story here: Scientists survey an Orange County neighborhood’s nonnative lizard populations

As a side note, the details for the original record (as far as I know) of A. sagrei in California are as follows:

The first published documentation was in Herpetological Review 45(4), 2014, an edited version of which you can read below:

ANOLIS SAGREI (Cuban Brown Anole). USA: CALIFORNIA: San Diego Co.: Vista, elev. 158 m) 19 July 2014.
C. Mahrdt, E. Ervin, and L. Geiger. Verified by Bradford D. Hollingsworth. San Diego Natural History Museum (SDSNH 76128–76133).

New county and state record (Granatosky and Krysko 2013. IRCF Rept. Amphib. 20[4]:190–191)
Four adult males and two hatchling specimens were collected on a one-acre parcel landscaped with palms, cycads, and several species of tropical plants and ground cover. Several boulders scattered throughout the parcel were used as perch sites for male lizards. An additional 16 adults and six hatchlings were observed in the two-hour site visit (1030–1230 h). Adults were also observed beyond the property indicating that this population is established and likely expanding through the contiguous tropical landscaping of neighboring properties. According to the property owner, he first observed the species in August 2012 shortly after receiving shipments of palm trees in May–August originating from suppliers located in the Hawaiian Islands.

CLARK R. MAHRDT, Department of Herpetology, San Diego Natural History Museum, San Diego, California 92102, USA (e-mail: leopardlizard@ cox.net);
EDWARD L. ERVIN, Merkel & Associates, Inc., 5434 Ruffin Road, San Diego, California 92123, USA;
GARY NAFIS, (www.californiaherps.com).

More information on A. sagrei in California can be found here

Revisited: What is an ecological community?

As I mentioned in a previous post (1), community ecology is a confusing field, confounded by the interchangeable use of many fundamental terms.

A group of graduate students and I discussed this paradigm and thought we would see what people’s own interpretations were, as an update and extension of a previous exercise conducted by Fauth et al. (1996). We created an online poll asking contributors to describe which factors are most important in defining the following key terms in community ecology: ‘community,’ ‘assemblage,’ ‘guild’ and ‘ensemble.’

There was certainly a lot of variation! We decided it was interesting enough to draft the results up into a manuscript, and it has eventually found some light in Ecology and Evolution. Specifically, we discussed the interpretation of each term from the perspective of undergraduate, graduate, non-academic, and professor perspectives, and conducted a thorough review of many ecology and evolution textbooks to investigate similarities in use. The abstract is detailed below, and you can find a link to the original paper here. Many thanks to all of you who contributed to the survey, your input it very much appreciated!

Abstract:

Community ecology is an inherently complicated field, confounded by the conflicting use of fundamental terms. Nearly two decades ago, Fauth et al. (1996) demonstrated that imprecise language led to the virtual synonymy of important terms and so attempted to clearly define four keywords in community ecology; “community,” “assemblage,” “guild,” and “ensemble”. We revisit Fauth et al.’s conclusion and discuss how the use of these terms has changed over time since their review. An updated analysis of term definition from a selection of popular ecological textbooks suggests that definitions have drifted away from those encountered pre-1996, and slightly disagreed with results from a survey of 100 ecology professionals (comprising of academic professors, nonacademic PhDs, graduate and undergraduate biology students). Results suggest that confusion about these terms is still widespread in ecology. We conclude with clear suggestions for definitions of each term to be adopted hereafter to provide greater cohesion among research groups.

Stroud_figure1
Figure 1. Relative interest in community ecology terms from 1977 to 2013, as reflected by respective citation histories (trends are overlayed, not stacked). The publication date of Fauth et al. is indicated by a vertical dashed line. Terms were searched for in the“ecology” category of ISI Web of Science (accessed 20 February 14).

Stroud, J.T., Bush, M.R., Ladd, M.C., Nowicki, R.J., Shantz, A.A., and Sweatman, J. (2015) – Is a community still a community? Reviewing definitions of key terms in community ecology. Ecology and Evolution, 5(21): 4757-4765

Although one tragedy did occur – we were a month too late to get into the issue sporting a beautiful green anole as the cover photo! Credit goes to Simon Lailvaux and colleagues for getting yet another anole front page.

Battling Crested Anoles (A. cristatellus) in South Miami, FL

While out watching lizards last week with my undergraduate research assistant extraordinaire, Oliver Ljustina, and fellow SoFlo anole Ph.D. student Winter Beckles, we happened upon a pair of male crested anoles (Anolis cristatellus) ready to rumble! This is quite early – but not unheard of – in the season for the commencement of territorial disputes, so it was a surprise to see them locking horns so aggressively. This couple were battling fairly high in the tree, at approximately 3m.

Anyway, here are the pictures!

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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!