Perch Height Research Articles

Where should I perch? The effects of body size, height, and leaf surface on the vertical perching position of dung beetles (Scarabaeidae: Scarabaeinae) in an Amazonian area

AbstractAmong dung beetles, ‘sit and wait’ comprise a common strategy, in which individuals perch on leaves. The goal of this study was to assess the spatial dynamics of dung beetle perching in a region of the Amazon. We analysed the intra‐ and interspecific relationships between individual body size, leaf area, leaf shape, and the height at which beetles perched. When analysing intraspecifically, the larger individuals of Canthidium bicolor perched higher than the small ones. When considering the three most abundant species, the smallest species (C. bicolor) perches lower, the intermediate species (Canthidium deyrollei) perches higher, and the largest species (Canthon triangularis) perches at an intermediate height. The leaf area also explained the vertical distribution, both when considering all individuals and intraspecific for C. bicolor, where there is a positive relationship between leaf area and perch height. Our results suggest that intra‐ and interspecific perching dynamics also depend on species life history, which could be further analysed under functional group approaches.

Tracking perching behavior of cage-free laying hens with deep learning technologies

Providing perches in cage-free (CF) housing offers significant benefits for laying hens, such as improved leg muscle development, bone health, reduced abdominal fat, and decreased fear and aggression. A precise detection method is essential to ensure that hens engage in perching behavior from an early age, as manual observation is often labor-intensive and sometimes inaccurate. The objectives of this study were to (1) develop and test a deep learning model for detecting perching behavior; and (2) evaluate the optimal model's performance on detecting perching behavior of laying hens of different ages. In this study, recent deep learning models, that is, YOLOv8s-PB, YOLOv8x-PB, YOLOv7-PB, and YOLOv7x-PB, were developed, trained and compared in detecting perching behavior in 4 CF rooms (200 hens/room). Perch height was up to 1.8 m from the litter floor and situated 1.5 m below the cameras. A total of 3,000 images were used, with each image featuring at least 1 hen perching. The models' detection accuracies and their performance across different age groups of hens were compared using 1-way ANOVA at a 5% significance level. The results showed that the YOLOv8x-PB model outperform all other models used, achieving the precision of 94.80%, recall of 95.10%, and mean average precision (mAP@0.50) of 97.60%. While all models proved over 94% detection precision. With optimal model, PB detection precision was highest (97.40%) for peaking phase followed by prelay (95.20%), grower (94.80%), developer (94.70%) and layers (92.70%) phases while the lowest detection precision (88.80%) was for starter phase. Detection performance was somewhat reduced by the overlapping of birds during perching and occlusion. Overall, the YOLOv8x-PB model was the most optimal in detecting perching behavior, proposing a valuable tool for CF producers to monitor the perching activities of laying hens automatically.

Trophic niche of four sympatric direct-developing frogs (Anura: Strabomantidae) from Eastern Brazilian Amazonia

Knowledge on the ecology of many Amazonian anuran species is still incipient, especially when it comes to resource partitioning. Here, we studied dietary variation of four Pristimantis species (P. chiastonotus, P. crepitaculus, P. gutturalis and P. zeuctotylus) from Eastern Brazilian Amazonia during the rainy and dry seasons. From 226 stomach contents retrieved through stomach-flushing, we observed that the four sympatric species can explore the generalist, sit-and-wait, and opportunistic foraging strategies, feeding mainly on highly mobile arthropods such as Diptera, Coleoptera, Hymenoptera, Hemiptera and Orthoptera, which were the most important prey categories. We found significant differences among the species for the volumetric composition of prey, and the amount of prey consumed was the main predictor for this condition in most species. The type of microhabitat was also a predictor for feed volumetric composition in some species. We report a higher perching height for P. chiastonotus, and lower perching in P. gutturalis; the first species had a wider dietary spectrum. These findings contribute to the understanding of resource partitioning among sympatric and closely related species.

Sexual dimorphism and ecomorphology of the Berthold’s bush anole (Polychrus gutturosus) in Costa Rica

Abstract Morphological variation present within a species is the result of sexual or natural selection and determines the ecological relationships (i.e., ecomorphology) and the degree of sexual dimorphism. For most lizard species, either males or females are the larger sex, suggesting that selection operates differently on each sex. Thus, differences in morphology can determine the habitat use made by males and females. Here we use the Berthold’s bush anole (Polychrus gutturosus), a rare arboreal, diurnal lizard, to examine whether morphological and ecological measures differ among sexes and whether such potential differences emerge as a result of resource partitioning. We measured the morphology of wild individuals from one population and from preserved specimens collected in Costa Rica. We collected data on nine morphological measurements, nocturnal body and air temperatures, and sleeping perch height. We measured 45 wild individuals (22 males and 23 females) and 17 preserved specimens (6 males and 11 females). We found a female-biased body size, and male-biased tail length, head dimensions, and limb lengths. We also observed differences between males and females in body color and the size and shape of femoral pores, although these differences require quantification. We did not find sex differences in sleeping perch height or nocturnal body temperature. Our results demonstrate that resource partitioning does not explain differences among sexes, and that female-biased body size in P. gutturosus might reflect selection operating on increased fecundity.

Habitat restoration to conserve the Little Vermilion Flycatcher on Santa Cruz Island, Galapagos.

The endemic Little Vermilion Flycatcher (LVF), Pyrocephalus nanus, has suffered a drastic decline on Santa Cruz Island, where it was common 30 years ago. Currently, less than 40 individuals remain in the last remnants of natural humid forest in the Galapagos National Park on this island. This small population has low reproductive success, which is contributing to its decline in Santa Cruz. Previous studies have identified Avian Vampire Fly, Philornis downsi, parasitism, changes in food sources, and habitat alteration as threats to this species. In Santa Cruz, invasive plants may strongly affect the reproductive success of the LVF because they limit accessibility to prey near the ground, the preferred foraging niche of these birds. Since 2019, we restored the vegetation in seven plots of one hectare each by removing invasive blackberry plants and other introduced plant species. In all nests that reached late incubation, we also reduced the number of Avian Vampire Fly larvae. In this study, we compared foraging and perch height, pair formation, incubation time and reproductive success between managed and unmanaged areas. As predicted, we found significantly lower foraging height and perch height in 2021 in managed areas compared to unmanaged areas. In 2020, daily failure rate (DFR) of nests in the egg stage did not differ between management types; however, in 2021, DFR in the egg stage was significantly lower in managed areas than in unmanaged areas. The DFR during the nestling stage was similar between managed and unmanaged areas in 2020, but in 2021, only nests in managed areas reached the nestling stage. Females brooded significantly more during the incubation phase in managed areas. Additionally, we found significantly higher reproductive success in managed areas compared to unmanaged areas in 2021, but not in 2020. Habitat restoration is a long-term process and these findings suggest that habitat management positively affects this small population in the long term.

Use of evergreen and deciduous plants by nocturnal-roosting birds: A case study in Beijing

With continually increasing urbanization, the land cover in urban areas continues to change, resulting in the loss of biodiversity. Birds are highly sensitive to changes in habitat. Most forest birds perch on plants that provide increased safety to reduce the risk of predation, and small birds may also consider insulation when using roosting plants in winter because of cold weather. Landscaping plants thus shape the nocturnal roosting environment of urban birds, and proper planting is essential for the survival of birds at night. The use of roosting plants by urban birds should therefore be studied to provide a reference for landscaping. In the current study, we observed 1865 nocturnal roosting birds in Beijing from 2021 to 2022, with 23 species of birds from 12 families and 45 species of plants from 22 families recorded. Juniperus chinensis exhibited the highest bird rarity-weighted richness, followed by Fraxinus pennsylvanica, Phyllostachys propinqua, Pinus tabuliformis, and Ulmus pumila. The diameter at breast height, tree height, and crown width of plants used by birds was largest in summer and smallest in winter, and the perch height of birds was the highest in spring and summer and the lowest in winter. Birds used the highest proportion of deciduous plants in summer and the highest proportion of evergreen plants in winter. A significant seasonal difference in the use of evergreen and deciduous plants by small birds was noted, with a preference for deciduous plants in summer and evergreen plants in winter, while this preference was not found in large birds. These findings indicate that evergreen plants provide a vital nocturnal roosting environment for small birds in winter. To provide a better nocturnal roosting habitat for urban birds, we recommend paying attention to the combination of evergreen and deciduous plants when carrying out landscape construction.

Predator-driven behavioural shifts in a common lizard shape resource-flow from marine to terrestrial ecosystems.

Foraging decisions shape the structure of food webs. Therefore, a behavioural shift in a single species can potentially modify resource-flow dynamics of entire ecosystems. To examine this, we conducted a field experiment to assess foraging niche dynamics of semi-arboreal brown anole lizards in the presence/absence of predatory ground-dwelling curly-tailed lizards in a replicated set of island ecosystems. One year after experimental translocation, brown anoles exposed to these predators had drastically increased perch height and reduced consumption of marine-derived food resources. This foraging niche shift altered marine-to-terrestrial resource-flow dynamics and persisted in the diets of the first-generation offspring. Furthermore, female lizards that displayed more risk-taking behaviours consumed more marine prey on islands with predators present. Our results show how predator-driven rapid behavioural shifts can alter food-web connectivity between oceanic and terrestrial ecosystems and underscore the importance of studying behaviour-mediated niche shifts to understand ecosystem functioning in rapidly changing environments.

Differences in perch height and response to intruders for territorial and non-territorial Calopteryx maculata (Odonata: Calopterygidae)

In the damselfly Calopteryx maculata, territorial males court potential mates and guard ovipositing females near the surface of the water. We conducted a survey and an experiment to determine whether there was a relationship between territoriality (site fidelity and agonistic behavior) and perch height. In the survey, males were captured, numbered, and released, and their perch height and location along a stream was noted for two weeks. Mean perch height was positively correlated with total distance travelled and negatively correlated with the number and percentage of times observed at the same site. Males that travelled less than 4 m had a significantly lower mean perch height than males that travelled more than 4 m. We conclude that males with greater site fidelity perch lower than males that travel widely. To test for a relationship between agonistic behavior and perch height, live male and female decoys, and a stick control, were run along a 20 m zip-line at two heights (25 cm and 75 cm), and the responses of resident males were recorded. Resident males that perched low (< 1 m high) approached decoys more often than resident males that perched high, and low-flying decoys were approached more than high-flying decoys. We conclude that territorial males—identified by greater site fidelity and agonistic behavior—perch lower than other males and are particularly responsive to low flying intruders. The benefits and costs of perching low and responding to low-flying intruders are discussed.

Ontogeny of sleeping behaviour in four solitary species of Anolis lizard

Abstract Despite the nearly ubiquitous nature of sleep in the animal kingdom, behavioural research on sleep has focused on a few model organisms and widespread behaviours studied in artificial laboratory settings. In this study, we examine the ontogeny of sleeping perch selection in four closely related species of arboreal lizard in situ. The study species each occupy similar habitats and share ‘solitary’ ecology wherein potential lizard competitors are absent, thus providing four partially independent replicates with which to test hypotheses. We find that structural niche, analysed as perch height, varies by age and sex. Males sleep higher than females and adults sleep higher than juveniles in three of four species. Adults exhibit greater variability in sleep site selection. These patterns may reflect diurnal behaviour or indicate selective differences in sleeping perch variability across sex and ontogeny.

Phenotypic diversity facilitates niche partitioning in a sky island assemblage of spiny lizards

Abstract If closely related species should be more similar and therefore more likely to compete for resources, why do we see so many examples of species-rich congeneric communities in nature? To avoid competition, many species possess suites of traits associated with differential resource use – or ecomorphologies – that promote niche differentiation with co-occurring species. Yet, the axes through which niche partitioning evolves and the traits involved are still poorly understood in most systems. Island systems, in which species interactions can form strong forces of selection due to limited resources, provide valuable insights into how ecomorphological diversity contributes to coexistence. Here, we examined axes of resource use and morphological traits that facilitate niche partitioning in a community of spiny lizards (genus Sceloporus) in a sky island system, the Chiricahua Mountains of southeastern Arizona, USA. By quantifying structural, temporal and thermal niche use for over 300 co-occurring lizards from four species over three field seasons, we show that sympatric species diverge primarily in perch height and type, but also in thermal and temporal resource use. Our results further demonstrate interspecific divergence in a suite of phenotypic traits known to covary with ecology in other lizard radiations, including body size, scale size, hindlimb length, foot length and dorsal coloration. Studies of niche partitioning and ecomorphology, especially of closely related species, deepen our understanding of how diverse communities assemble and how morphological diversity accumulates across the tree of life, and our findings highlight the importance of examining multiple axes of resource use to better understand these processes.

The relationships of breeding stage to daytime singing behaviour and song perch height in Bermuda white‐eyed vireos Vireo griseus bermudianus

Bird song is crucial for attracting mates and defending territories, but different types of song or different singing behaviours may be involved in acquiring or maintaining each resource. Furthermore, male songbirds may adjust when and where they sing throughout the breeding season, depending on their breeding stage. However, such relationships remain untested in several avian taxa. Here, we studied male Bermuda white‐eyed vireos Vireo griseus bermudianus, a passerine with two distinct song types (discrete and rambling), to test the mate attraction and territory defence hypotheses. We compare song production and song perch height among different stages of the breeding season and during the non‐breeding season. We show that male vireos produce both song types during the breeding and non‐breeding seasons, suggesting dual roles in mate choice and territorial defence. Song production did not differ significantly between the breeding and non‐breeding seasons, but, within the breeding season, males without nesting duties sang significantly more songs than males with nesting duties. Song perch height was higher during the breeding season versus non‐breeding season, among males without nesting duties compared to males with nesting duties, and when males produced discrete versus rambling songs. Our findings suggest that male vireos increase their conspicuousness to prospecting females by increasing song production and song perch height, and that they sing during the breeding and non‐breeding seasons to defend year‐round territories. Collectively, our study supports the mate attraction and territory defence hypotheses of bird song.

Perch selection of three species of kingfishers at the Pantanal of Brazil

Selecting a suitable perch can offer many benefits for fish–eating birds such as kingfishers. However, factors affecting perch selection in these species remain poorly studied. We studied perch selection in three species of kingfishers inhabiting the Pantanal of Brazil during the dry season: Megaceryle torquata, Chloroceryle amazon, and Chloroceryle americana. First,we determined the habitat use of the three species. We then assessed the perches these kingfishers used based on four ecologically relevant traits: (1) artificial or natural, (2) perch height, (3) distance to the water, and (4) plant cover. We hypothesized that artificial perches could be more likely selected as they may offer better visibility to fish. We used a resource selection function (RSF), in a case/control design, solving it by model selection of six conditional logistic regression competing models. The probability of presence was independent of the artificial origin of a perch for the three species. It was also independent of the other studied variables, except for individuals of C. amazona, which selected higher perches. We conclude that artificial perches do not influence perch selection of the studied kingfishers, which may indicate that these artificial structures are not altering their behavioral choices.

Perch height in broiler chickens at various ages: Frequency of use and behavioural time-budget

Chickens are motivated to perch, but the optimal height at which perching opportunities should be placed to facilitate access and use remains unclear. This study evaluated the ability of meat chickens to reach a perching platform set at different heights. Two experiments were carried out to test the hypothesis that perch height arrangement can contribute to its use during rearing. In the first experiment, the perching platform was placed at 0 cm (on the same level as the litter) during the first week of age; thereafter, it was alternated between 0, 10, 20, 30, and 40 cm in height within each day of the week for the remaining five weeks. In the second experiment, the platform height was alternated in 5 cm increments, hence between 0, 5, 10, 15, and 20 cm within each day of the week and tested over the same age period. The statistical model used included the fixed effects of age (in weeks), platform height and their interactions, and for the random effect of pen nested within treatment. In Experiment 1, chickens between weeks 2 and 6 of age used platforms more at 10 than 20 cm and did not reach the 30 and 40 cm heights. In Experiment 2, chickens used perches throughout the period of the 2nd to the 6th weeks of age but used higher perches (up to 20 cm) during the 3rd and 4th weeks of age. The platform height allowed perching behaviour when located at a maximum of 20 cm from the litter. Gradual 5 cm increases in perch height are likely to have been the reason for greater use in Experiment 2. In conclusion, chickens are motivated to use perches or elevated areas when placed at a height of up to 20 cm from floor level, and stepping them up in small increments of 5 cm may increase their use.

Lizard species on three islands off the Mexican Pacific Coast: effects of insularity

This study provides a descriptive panorama of the lizard communities on 3 islands and the mainland on the Pacific coast of Mexico, estimating the effect of insularity (ecological changes between lizards on the islands and on the mainland) on lizard populations. The panorama included the number of species, encounter frequency and age classes. The insularity effects were estimated by comparing these variables, as well as basking behavior, activity related to microclimate, and perch height among the islands and the mainland. Of 11 species recorded, 8 occurred on the islands; however, every insular community was composed of 3 to 5 species (4 are protected by Mexican law). The encounter frequency for all species ranged between 11 and 0.1 individuals per hour. Lizard communities were predominantly composed of adults. Only 2 lizard species, Aspidoscelis communis and A. lineattissima, were shared among all sites, showing no insularity effects on the encounter frequency nor basking behavior. There were signs of insularity, however, on age classes and a clear effect on perch height, suggesting niche expansion. The study contributes to the regional knowledge of lizard species, as well as to ecological theories such as niche expansion and density compensation.

Do Suburban Populations of Lizards Behave Differently from Forest Ones? An Analysis of Perch Height, Time Budget, and Display Rate in the Cuban Endemic Anolis homolechis

Urbanization transforms natural ecosystems into novel habitats, which can result in negative consequences for biodiversity. Therefore, it is important to understand the mechanisms of maintenance of native species in urbanized environments, including behavior—which can act as a fast response to rapid environmental changes. We compared some behavioral traits between two suburban and two forest populations of Anolis homolechis. Direct observations of 779 individuals revealed that perch height was positively influenced by body size, but not by sex. Suburban individuals perched higher than forest ones, and even more so in the afternoon compared to the morning; a behavior that was not observed in forests populations. These differences might be due to a change from foraging activities in the morning to vigilance, display, and/or thermoregulation in the afternoon, promoted by suburban habitat conditions (e.g., higher predator abundance, open habitat structure, and urban heat). Video recordings of 81 focal individuals showed that males were more active than females (i.e., spending less time in stationary behavior and having a higher display rate), with no significant effect of habitat type. As some of our results diverge from previous studies on invasive anoles, we recommend extending comparative studies of urban and non-urban populations to other native Anolis.

Nocturnal surveys of lined seahorses reveal increased densities and seasonal recruitment patterns.

Although the nighttime ecology of organisms remains understudied, nocturnal surveys play an integral part in assessing fish assemblages and the selective forces shaping them. Eleuthera (Bahamas) contains an unusual population of lined seahorses (Hippocampus erectus) in an anchialine lake, possessing morphological characteristics distinct from those found in the ocean. Population surveys for seahorses and their potential predators were conducted at midnight and midday during wet and dry seasons, with belt transects perpendicular to the shoreline that increased in depth away from shore. Nocturnal surveys uncovered seahorse densities 259% higher than daytime transects on average. Sex ratios were consistently male-biased, and the frequency of animals from different reproductive categories varied significantly by time of day, with gravid males observed around the clock but females and nongravid males observed more often at night. Spatial and seasonal recruitment was detected for the first time in this species, with an increase in juveniles detected in the shallow ends of transects during dry season surveys. Juvenile recruitment is poorly understood across syngnathid fishes, so the detection of early recruits at night has broad implications for this fish family. Seahorses from all reproductive categories were perched significantly higher in the water column during the night regardless of their depth or season. Predator densities followed a similar pattern with higher densities observed at night, indicating that elevated nocturnal perch height may be a response to predator presence. However, the selective agents driving these nocturnal behaviors have yet to be identified. Considering H.erectus is listed on the IUCN Red List as "Vulnerable," the increase in nocturnal population size and the detection of juveniles has crucial implications for understanding their ecology, recruitment, and conservation.

The Crimean population of the lesser grey shrike (Lanius minor) has low behavioural flexibility in its response to approaching humans

The ongoing growth of the human population will increase the rate of wildlife-human interactions. High levels of animal tolerance and flexible responses towards human presence seem to be among the key mechanisms behind successful wildlife-human coexistence, but this behaviour remains unexplored for most populations and species of animals. Here, we investigate the escape behaviour (measured as flight initiation distance) of the Crimean population of a charismatic and declining bird species, the lesser grey shrike (Lanius minor). We examined its relationship with starting distance of the approaching human, directness of that approach (direct or tangential), habitat type (rural or suburban), and height of the perch used by shrikes. We found that the starting distance was significantly associated with escape responses of shrikes to approaching humans. In contrast, we found no significant association between escape responses and directness of approach, habitat type, or height of perch. Our results indicate that the lesser grey shrike may exhibit low flexibility in their escape responses towards humans which may have implications for their conservation management. Our results also indicate that the widely used 30 m threshold for minimum starting distance may be insufficient for rural populations, even of small passerines.

Host community-wide patterns of post-fledging behavior and survival of obligate brood parasitic brown-headed cowbirds.

The antagonistic arms races between obligate brood parasites and their hosts provide critical insights into coevolutionary processes and constraints on the evolution of life history strategies. In avian brood parasites-a model system for examining host-parasite dynamics-research has primarily focused on the egg and nestling stage, while far less is known about the behavior and ecology of fledgling and juvenile brood parasites. To provide greater insights into the post-fledging period of generalist brood parasites, we used handheld and automated telemetry systems to examine the behavior and survival of fledgling brown-headed cowbirds (Molothrus ater). Our host community-wide analysis (data on cowbirds fledged from different host species were pooled) shows that fledgling cowbirds' follow patterns of movement and survival found across the post-fledging literature on parental passerine species. Cowbird fledgling survival was lowest during the first 3days post-fledging, whereas daily rates of survival neared 100% after about 16days post-fledging. Cowbird daytime post-fledging activity rates, perch heights, and distance from the natal area all increased with fledging age and young generally gained independence from host parents at 3-4weeks post-fledging, with approximately the same latency as has been observed in studies on fledglings of cowbird host species. Our research demonstrates how automated telemetry systems can overcome past methodological limitations in post-fledging research and provides an important foundation for future studies examining adaptations that cowbirds and other brood parasites use to exploit hosts during the post-fledging period.

Commercial broiler breeder pullet hens use perches but show no preference for perch type or height

An important behavioral need for laying hens is perching, but few studies have investigated perching behavior in commercial broiler breeder pullets. The aim of this study was to investigate perching behavior throughout the pullet period and preferences for different perch types and heights. We also investigated the effect of hybrid on perching and the potential effect of perches on keel bone damage (KBD) and footpad dermatitis (FPD). We followed four commercial broiler breeder pullet hen flocks (Ross 308, n = 2 and Hubbard JA 757, n = 2), each with three groups of birds (n = 2 500 hens); A-group; four A frames consisting of four perch types (plastic, steel square, steel round and wood) placed on different heights (35 cm and 95 cm); S-group; Siesta perches (a plastic perch 15 cm high) and C-group; control group without perches. Perch use was recorded by counting number of birds on the perches during the last hour before the light went off, at week 2, 5, 6, 7, 10, 12 and 15. At week 16, footpad dermatitis, keel bone deformations and keel bone fractures were scored in 30 random birds in each group (n = 90 birds/flock). Hubbard birds perched significantly more than Ross birds (P < 0.0001), and more birds perched on the Siesta perches than on the A frames (P = 0.046). Perching increased with age for Hubbard birds (P < 0.05), but not for the Ross birds. There were no effects of perch height or perch types on number of birds observed on the perches. There were no observed cases of bumblefoot, breast blisters, keel bone deformations or keel bone fractures. The incidence of FPD was low, with 73.6% of assessed birds receiving a score of 0, with no significant differences between hybrids or perch groups. In conclusion, Hubbard birds perched more than Ross 308 birds, and all birds perched more with age. None of the hybrids showed any preferences for perch type or height and increased perching had no negative effects on important health parameters. Broiler breeder pullets should therefore be given access to perches from day 1 to promote training and perch use.

Influence of microhabitat use on morphology traits of three species of the Anolis sericeus complex (Squamata: Dactyloidae) in Mexico

The relationship between microhabitat use and morphology in Anolis lizards has been well studied in the Caribbean islands. However, studies of ecomorphology are scarce for the vast majority of mainland Anolis species. Thus there is a great lack of knowledge on how microhabitat use may influence the morphology of most mainland Anolis species. In this study we evaluated the relationship between morphology and microhabitat use in three sister species of the genus Anolis (A. sericeus, A. unilobatus and A. ustus) inhabiting the mainland and examined whether sympatric coexistence with other Anolis species affects microhabitat use and morphology of Anolis sericeus. The results of this study showed that A. ustus perches on higher, thinner, and warmer branches than its sister species (A. sericeus and A. unilobatus), and that snout–vent length, arm, forearm and femur length and weight of the three species are positively correlated with perch diameter, while the number of subdigital lamellae and weight are slightly correlated with perch height. In addition, the absence of sympatric Anolis species increases the variability in perch height, weight, arm and forearm length, and hip width observed in A. sericeus. Differences in limbs length, head length, weight and number of lamellae enabled the identification of two groups of species exploiting statistically different microhabitats. The relationship between microhabitat use and morphology indicates that some morphological traits, such as locomotor structures, weight and number of subdigital lamellae of the three species are influenced by microhabitat use and that interspecific competition may reduce variability in the height of perches used.