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!
A common concept in ecology is that predators have a strong influence on the behaviour of prey species. Anolis lizards have been used as a classic model system to investigate the effect of predator presence on the behavioural response of prey species. On small experimental islands in the Bahamas the manipulated introduction of curly-tailed lizards (Leiocephalus carinatus), a large terrestrial anole-predator, has resulted in brown anoles (Anolis sagrei) shifting higher up in the vegetation, presumably in an understandable effort to avoid being eaten (1, 2, 3). However, predator-prey interactions such as these which may shape community structure are often difficult to observe.
Here in Miami FL we have a rich and diverse, although largely non-native, lizard community. There are two species of “crown-giant” anoles, the Cuban knight anole (A. equestris) and the Jamaican giant anole (A. garmani), that could be potential predators of smaller anoles in the canopy of trees and upper half of tree trunks (although see Giery et al. 2013 for an empirical analysis that suggests this may not be the case). Additionally, there are several large, terrestrial lizards present which may be filling a similar role to curly-tails in the Bahamas.
Potential lizard predators in south Florida:
– *Red-headed agama (Agama agama)
– *Cuban knight anole (Anolis equestris)
– Jamaican giant anole (Anolis garmani)
– *Brown basilisk (Basiliscus vittatus)
– Spiny tailed iguana (Ctenosaura similis)
– Curly-tail lizard (Leiocephalus carinatus)
– Giant day gecko (Phelsuma grandis)
– Black and white tegu (Tupinambis merianae)
*Present at Fairchild Tropical Botanical Gardens
Earlier this afternoon, while taking a break from my office at Fairchild Tropical Botanical Gardens (a hot spot for any anologist visiting Miami; 1, 2, 3, 4) in a typical graduate student effort to put off work that I should be doing instead, fellow lab member Evan Rehm and I noticed some scuffling in a nearby bush. At around 2.5m, and admittedly on relatively precarious branches by this stage, sat an adult female African red-headed agama (A. agama) around 30cm from an adamantly motionless adult male Cuban brown anole (A. sagrei)! As we moved towards the bush the agama was quick to ungraciously thump itself to the floor, while the brown anole remained still. On closer inspection, it soon became apparent why both lizards were so high.
Adult male Cuban brown anole (A. sagrei) found ~2.5m high in Miami FL, supposedly following a predation attempt from an African red-headed agama (A. agama) – JStroud
The significance of tail loss/damage in a population is still debated. The classical view argues that high proportions of tail damage indicates high predation pressure, therefore prey populations are under high predation stress (1). Alternatively, high proportions of tail damage could indicate low predator efficiency, which would suggest prey populations are experiencing low predation stress (1, 2). But the debate doesn’t stop there! Having already lost a tail, a lizard may experience either a resulting increase or decrease in predation depending on the predator species and its associated foraging tactic (1).
The extent of tail damage is clearer in this photo. The lizard had autotomised the lower half of it’s tail however a secondary half-completed break is also evident – JStroud
African red-headed agamas (A. agama) are similar morphologically to curly-tailed lizards (L. carinatus), although are taxonomically distinct (Agamidae and Leiocephalidae, respectively). Predation of anoles by agamas in Miami has not previously been officially recorded, and the impact of these large predators remains unclear. Unlike in the Bahamas, there are multiple predators in the same geographic vicinity that anoles need to be aware of. For example, at Fairchild, brown anoles (A. sagrei) could be eaten from below by agamas, eaten at intermediate levels by basilisks and eaten from above by knight anoles!
South Florida is a tough place to be an anole!
Adult male African red-headed agama (A. agama) at Fairchild Tropical Botanical Gardens, Miami FL. The population of agamas is localised to the botanical gardens; the source remains unclear but is likely an introduction from the pet trade – JStroud
One of the greatest threats to ecosystems is the continued introduction and spread of invasive species, which are commonly introduced to new areas by humans. Invasive species not only threaten nature preserves, but can harm commerce (such as zebra mussels damaging ships, or lionfish devastating fishing grounds) and pose a threat to public health by spreading disease (such as introduced rodents and mosquitoes). However, despite the problems caused by invasive species, we still know surprisingly little about what makes certain species successful in new ranges.
For my dissertation research in the Martin lab at the University of South Florida, I hope to identify the mechanisms that enable these species to survive and spread following an introduction. By identifying some of these mechanisms, we will be able to focus control efforts in a more effective manner by ascertaining which species have this potential. Specifically, I study Anolis sagrei, the brown anole, which is native to Cuba and the Bahamas, but is widespread across Florida where it has displaced the native green anole. My research aims to address if A. sagrei is able to be so successful in its introduced range in Florida because it changes the way it uses dietary resources as it invades new territory. The results of my study will not only fill a gap in the knowledge that we have on a common invasive species in Florida, but will also provide a stepping stone for future research on invasive species from other taxonomic groups.
The scientific community is no exception to having cope with budget cuts. Many labs that have traditionally depended on funding from federal agencies are finding money for research (especially ecological research) harder to come by. That is where the general public comes in. Crowd funding provides an opportunity for the general public to personally contribute to research projects and allows scientists to reach out and bridge the gap between the public and scientific communities. The support I receive from funders will be used to help me travel to different locations across the introduced range of A. sagrei in Florida and for sample processing at the University of South Florida. I will be sampling from sites close to the point of original introduction (Key Largo and Miami-Dade, FL), as well as sites where brown anoles have been reported for less than 20 years.
Please help to support my research: http://rkthb.co/25521
You can also keep up with my research by following me on Twitter @OffbeatScience and visiting my website.
Firstly, let me start by offering my sincere apologies for the standard of photography you are about to view. As you AA readers have become accustomed to Jonathan’s flowing prose, and other members’ excellent use of modern photographic equipment, I must warn you not to expect either here!
As has been mentioned previously, the IBS Conference was a tremendous success, and firstly huge congratulations must be passed on to (a potential anologist in the making?) Ken Feeley for all the hard work and effort. The lack of talks concerning arguably one of the world’s most studied vertebrate biogeographic systems did not detract from the high levels of anole hunting that ensued over the course of the conference!
After a wonderful afternoon visiting Miami’s most bizarre lizard community, the following day provided an opportunity for conversations to be followed up from the previous night’s conference dinner (as some graduate students’ memories may have appeared a little hazy on Saturday morning). Much of the day was spent wandering around FIU’s Biscayne Bay Campus eagerly trying to find the dozen knight anoles that were promised to us the previous night by resident expert, and thoroughly nice guy, Sean Giery.
Sean has spent the past 3 years observing the A. equestris community on this campus, and has assured me that he will bless AA readers with a synopsis of his eagerly awaited dietary analysis paper in the near future. The day started brightly, with two juveniles being found in close proximity to each other; however with just he and I as the only observers, it was tough to include these individuals in the promised dozen.
Juvenile knight anole found on a horizontal branch ~2m high. Photo by JStroud
At the start of lunch, and confronting the midday heat with the enthusiasm of schoolboys on a day trip, we regrouped with some extra eyes and headed back out to continue on our quest. Although A. sagrei, A. carolinensis and A. distichus were abundant, these were still not the target species. A loud thump behind us saw us all swivel in synchrony, like a troop of sunburnt and slightly dehydrated Michael Flatley fanatics, to be confronted by a rather startled green iguana that had just plummeted 10 feet after submissively losing a dispute to a larger male. The campus had previously been awash with a healthy population of green iguanas; however the big freeze of 2009 reduced this significantly so that the only survivors were those small enough to retreat underground.
I have extensively photographed Anole in an urban environment because they are so readily available here in south Florida literally outside my door and frequently indoors too. Despite the lamentations of displacement of the native Anolis carolinensis, they are frequently observed in my immediate area. I will present a few photos showing confrontations between the variety of West Indian Anole and the native green. Knight anole is also present, mostly juvenile as I do not observe fully grown specimens either because of adult movement to other areas or the wide variety of predators, mostly large birds. More about geckoes, basilisks and iguana will be posted in related forums.
I saw the recent posts about orange/red sagrei and I thought I might contribute another observation of orange-colored brown anoles. A few years ago while assisting another grad student with his dissertation work I spotted a few orange-colored brown anoles in a suburban yard in S. Florida. What I thought was most interesting about the observation was that: 1) there were multiple males (2-3) with orange color, and 2) many of the palms on which lizards were perched were a similar orange color. It got me thinking that it could be more than a coincidence.
The orange color on the trees, sidewalks, and other hard substrates in the area is from ground water with a high concentration of iron. When sprayed on the surface with sprinklers it mixes with oxygen and leaves an orange color. Many houses, signs, sidewalks, and even cars in S. Florida are graced with an arc or two of orange residue. I’ve yet to revisit this lawn or surrounding houses, but I bet there are quite a few more houses with orange lizards. For what it’s worth, I see and catch a lot of brown anoles further south in the Miami area and this is the only case of red/orange brown anoles I’ve seen yet. It’s possible that these lizards were covered in rust, but it didn’t look like it when I got one in my hand. It’s also interesting that all of the photos I’ve seen of orange-colored brown anoles are male, however I’ve only seen about 4 cases including this observation. Oh, and the dewlaps on these males were normal(ish), not like the cool one recently posted by Joe Burgess.
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