Undisturbed Rain Research Articles

Abundance and nesting sites characteristics of red-headed picathartes Picathartes oreas in Cross River State, Nigeria

This study assessed the abundance and nesting sites characteristics of red-headed picathartes (Picathartes oreas) in protected and unprotected forest in Cross River State, from August 2016 to January 2017. Data were collected through oral interviews, and field observations, using area search and quadrant methods. Data on bird and nest were tested using one-way ANOVA and t-test while tree species diversity indices were calculated using Paleontological Statistics Software Package, version 16. Results revealed that a mean of 38±52 individual bird from six colonies were sighted during the survey. Higher number of 20 (52.63%) individuals from two colonies was recorded in the undisturbed montane rain forest of the Okwangwo Division of the Cross River National Park than the disturbed montane rain forest with 18 (47.37%) individuals from four colonies. A total of 40 (50%; n = 20 each) nests of red-headed picathartes were sighted during the survey around the undisturbed and disturbed montane rain forest respectively. All (100%; n = 40) the nests observed were attached to the south-eastern side of the rocks and all the nests were constructed with mud mixed with grass. Colony Six was on the highest altitude with an elevation of 529 m, followed by colony two with an elevation of 342 m while the lowest elevation was 195 m recorded in colony three. Tree diversity index was higher in the protected forest (3.352; 3.227) than in the unprotected forest (1.846). Characteristic features of Picathartes oreas habitat were rock, hill, valleys and rivers and streams. It was evidenced by the study that Picathartes oreas still nests both in the disturbed and undisturbed forest but the level of disturbance and type of crops grown may have impact on the nesting behaviour. Therefore, anthropogenic activities should be regulated in the area, to ensure the conservation of Picathartes oreas.
 Keywords: Picathartes oreas; abundance; nesting sites characteristics; unprotected and protected forest.

Impacts of sediment derived from erosion of partially-constructed road on aquatic organisms in a tropical river: The Río San Juan, Nicaragua and Costa Rica.

Throughout the humid tropics, increased land disturbance and concomitant road construction increases erosion and sediment delivery to rivers. Building road networks in developing countries is commonly a priority for international development funding based on anticipated socio-economic benefits. Yet the resulting erosion from roads, which recent studies have shown result in at least ten-fold increases in erosion rates, is not fully accounted for. While effects of road-derived sediment on aquatic ecosystems have been documented in temperate climates, little has been published on the effects of road-induced sediment on aquatic ecosystems in developing countries of the tropics. We studied periphyton biomass and macroinvertebrate communities on the deltas of Río San Juan tributaries, comparing north-bank tributaries draining undisturbed rain forest with south-bank tributaries receiving runoff from a partially-built road experiencing rapid erosion. Periphyton biomass, richness and abundance of macroinvertebrates overall, and richness and abundance of Ephemeroptera, Plecoptera and Trichoptera were higher on the north-bank tributary deltas than the south-bank tributary deltas. These findings were consistent with prior studies in temperate climates showing detrimental effects of road-derived fine sediment on aquatic organisms. A Non-Metric Multidimensional Scaling (NMDS) analysis showed the impacted community on the south-bank deltas was influenced by poorly-sorted substrate with greater proportions of fine sediment and higher water temperatures.

Assessing avian diversity and community composition along a successional gradient in traditional Lacandon Maya agroforests

AbstractEvidence regarding the ability of agroforests to conserve biological diversity has been mixed; they tend to maintain avian communities with species richness similar to that of undisturbed forest ecosystems but generally do not completely preserve community composition. Using a combination of occupancy modeling and non‐metric multidimensional scaling on point‐count data, we assessed changes in avian community diversity and composition along a successional gradient in traditional Lacandon Maya agroforests and compared them to protected areas in the region. Bird species richness and diversity in Lacandon agroforests peaked in early secondary forest stages. These agroforests' mean Shannon–Weiner diversity was 5% higher than that of nearby protected areas, but their species richness was similar. Community composition in Lacandon agroforests changed throughout succession, with earlier stages supporting communities distinctly characterized by generalist species, while subsequent, less‐intensively managed stages tended to support more forest‐dwellers. The bird community observed in even the most mature secondary forest stages in Lacandon agroforests differed from that of undisturbed rain forest ecosystems. These results demonstrate the potential of traditional Lacandon agroforestry management to conserve avian biodiversity while ensuring food sovereignty for farmers. However, because the community composition of early‐successional stages was different than later stages, shortening fallow cycles and reducing forest cover to increase agricultural production will limit the species this system can support. This study illustrates the value of incorporating traditional agroecosystems into conservation planning as well as maintaining protected areas, because the latter serve as refugia for species that require undisturbed forest habitat in an agroecological matrix.Abstract in Spanish is available with online material.

Drivers of tropical rainforest composition and alpha diversity patterns over a 2,520 m altitudinal gradient.

AimWe sought to determine the relationship of forest composition and alpha diversity (the species diversity of a local assemblage) to altitude, soil, and spatial factors over a 440–2,950 m a.s.l gradient.LocationAltitudinal gradient on the Caribbean slope of the Talamanca Cordillera, Costa Rica.TaxonAngiosperm and gymnosperm trees, palms, and tree ferns.MethodsWe measured and identified all stems ≥10 cm dbh in 32 0.25‐ha undisturbed rain forest plots over the gradient. We determined compositional patterns using Non‐Metric Multidimensional Scaling (NMS) ordination, and used linear regressions to explore the relationship between four alpha diversity metrics and altitude. With variation partitioning (VARPART), we determined the compositional variation explained by altitude, soil, and spatial variables quantified using Principle Components of Neighbor matrices.ResultsWe identified 425 species. NMS axis 1 separated a lowland zone (440–1,120 m asl) from a transitional one dominated by holarctic Oreomunnea mexicana (1,400–1,600 m asl) and Quercus‐dominated forests at altitudes >2,100 m asl. The lowland zone was separated into two clusters of plots on NMS axis 2, the first in the 430–620 m asl range and the second at 1,000–1,120 masl. Regressions showed that all alpha diversity metrics were strongly negatively related to altitude (R 2 > 0.78). Overall, adjusted R 2 from VARPART was 0.43, with 0.30, 0.21, and 0.17 for altitude, soil, and space respectively. The respective adjusted R 2 of individual matrices, on controlling for the other two, was 0.06, 0.05 and 0.09 (p < 0.001).Main conclusionsThere are two well‐defined forest compositional zones on this gradient—lowlands 430–1,120 m asl and montane forests >2,150 m asl—with a transitional zone at 1,400–1,600 m asl, where lowland tropical and montane holarctic species are found together. Montane forests are very distinct in their composition and low alpha diversity. Vegetation and soil respond to altitude, and therefore temperature, as an integrated system, a model that goes beyond niche assembly as shown by the significant effect of space in the VARPART.

Habitat use and seed removal by invasive rats (Rattus rattus) in disturbed and undisturbed rain forest, Puerto Rico

AbstractDespite frequent occurrences of invasive rats (Rattus spp.) on islands, their known effects on forests are limited. Where invasive rats have been studied, they generally have significant negative impacts on native plants, birds, and other animals. This study aimed to determine invasive rat distribution and effects on native plant populations via short‐term seed removal trials in tropical rain forest habitats in the Luquillo Experimental Forest, Puerto Rico. To address the first objective, we used tracking tunnels (inked and baited cards inside tunnels enabling animal visitors’ footprints to be identified) placed on the ground and in the lower canopy within disturbed (treefall gaps, hurricane plots, stream edges) and undisturbed (continuous forest) habitats. We found that rats are present in all habitats tested. Secondly, we compared seed removal of four native tree species (Guarea guidonia, Buchenavia capitata, Tetragastris balsamifera, and Prestoea acuminata) between vertebrate‐excluded and free‐access treatments in the same disturbed and undisturbed habitats. Trail cameras were used to identify animals responsible for seed contact and removal. Black rats (Rattus rattus) were responsible for 65.1% of the interactions with seeds, of which 28.6% were confirmed seed removals. Two plant species had significantly more seeds removed in disturbed (gaps) than undisturbed forest. Prestoea acuminata had the lowest seed removal (9% in 10 days), whereas all other species had &gt;30% removal. Black rats are likely influencing fates of seeds on the forest floor, and possibly forest community composition, through dispersal or predation. Further understanding of rat–plant interactions may be useful for formulating conservation strategies.

Effects on soil chemistry of tropical deforestation for agriculture and subsequent reforestation with special reference to changes in carbon and nitrogen

While soils can act either as a source or as a sink for atmospheric carbon dioxide and nitrogen, depending on land cover change and management, there is a great need to improve our understanding of the dynamics of soil structure and chemistry following land conversion in tropical regions. In this study, we investigated various soil structural and chemical variables (bulk density, pH, cation exchange capacity, phosphorus, magnesium, potassium), soil carbon (C), soil nitrogen (N), δ13C, and δ15N in relation to conversion of rain forest to tea cultivation and subsequent changes due to agricultural abandonment and reforestation with Caribbean pine. Although Caribbean pine has shown potential for reforestation throughout Asia and Latin America, effects on soil properties in comparison with other land uses have not been quantified. Our study compared: (1) the original mixed-dipterocarp rain forest, (2) tea plantations, (3) Kekilla fernlands and (4) Caribbean pine plantations. Tea plantations show higher bulk density (BD) as an evidence of compaction. Although soil C concentration in tea plantations were lower than other land uses at 0–10cm, when bulk density was used with C as a composite measure, tea plantation showed the highest value for both soil C and N stocks. Disregarding tea plantations, Caribbean pine plantations had the highest C but showed the lowest N stocks at both soil depths. Soil δ13C and δ15N values of all land uses increase with increasing soil depth; but Caribbean pine plantations showed the greatest increase in δ13C at both soil depths (e.g. −27.82±0.38‰ at 0–10cm to −26.50±0.37‰ at 10–20cm). For both Kekilla fernlands and Caribbean pine plantations the relationship between δ13C and δ15N was strongly linear. By comparing the physical and chemical soil properties of these land uses with undisturbed rain forest, we established baseline data to determine influence of land conversion on soil properties. Based on soil pH, CEC and other major nutrients (P, K, Mg), there are strong legacy effects of land use potentially from both fertilization and fire. Our results also showed strong evidence that δ13C and δ15N was both increased with depth under pine reforestation and fernlands, suggesting soils can recuperate with a consistent input of litter and slower decomposition processes. There is some evidence that recruitment of natural regeneration beneath pine can help facilitate faster litter decomposition that can revert soil structure and fertility to a status similar to that of the original forest.

Corynespora aquatica . [Descriptions of Fungi and Bacteria

Abstract A description is provided for Corynespora aquatica . This fungus has been observed on decaying leaves submerged in a freshwater stream, in undisturbed rain forest. It is presumably a saprobe for at least part of its life cycle, but nothing else is known about its relation with associated plants. Some information on its dispersal and transmission and conservation status is given, along with details of its geographical distribution (North America (Mexico)).

&lt;strong&gt;&lt;strong&gt;&lt;/strong&gt;&lt;/strong&gt;&lt;p align="justify"&gt;Oribatid mites of the superfamily Oppioidea from Ecuador (Acari: Oribatida)&lt;/p&gt;

An annotated checklist of identified Ecuadorian Oppioidea (10 species of 10 genera of three families) is presented. The genera Hammerella, Taiwanoppia, subgenera Hammerella (Woasella), Taiwanoppia (Paragloboppia) and the species T. (P.) trichotos (Balogh et Mahunka, 1977) are recorded for the first time in Ecuador. One new species of the family Granuloppiidae — Hammerella (Woasella) parasufflata sp. nov. — is described from the upper organic soil layer in a mostly undisturbed rain forest. This species differs from the type species of the subgenus, H. (W.) sufflata Franklin et Woas, 1992 from Brazil by the absence of translamella, presence of two prodorsal tubercles, localization of notogastral (la, lm) and aggenital setae, localization of sensillar branches, morphology of some subcapitular setae and the location of lyrifissures iad.

New oribatid mites of the genera &lt;i&gt;Machadobelba&lt;/i&gt; and &lt;i&gt;Campachipteria&lt;/i&gt; (Acari: Oribatida) from Ecuador

Two new oribatid mite species, Machadobelba longiciliata sp. nov. (Machadobelbidae) and Campachipteria brevisetosa sp. nov. (Achipteriidae), are described from upper organic soil layer in mostly undisturbed rain forest of Podocarpus National Park, Ecuador. Machadobelba longiciliata sp. nov. is most similar to Machadobelba descombesi Mahunka, however it differs from the latter by the structures of sensilli and median notogastral tubercles, length of notogastral setae and presence of porose areas in anogenital region. Campachipteria brevisetosa sp. nov. is most similar to Campachipteria sibirica (Krivolutsky et Grishina), however it differs from the latter by the structures of sensilli and lamellar setae, and length of process of pteromorphs. The genus Campachipteria is recorded for the first time in Ecuador.

Production of alkaline cellulase by fungi isolated from an undisturbed rain forest of peru.

Alkaline cellulase producing fungi were isolated from soils of an undisturbed rain forest of Peru. The soil dilution plate method was used for the enumeration and isolation of fast growing cellulolytic fungi on an enriched selective medium. Eleven out of 50 different morphological colonies were finally selected by using the plate clearing assay with CMC as substrate at different pH values. All 11 strains produced cellulases in liquid culture with activities at alkaline pH values without an apparent decrease of them indicating that they are true alkaline cellulase producers. Aspergillus sp. LM-HP32, Penicillium sp. LM-HP33, and Penicillium sp. LM-HP37 were the best producers of FP cellulase (>3 U mL−1) with higher specific productivities (>30 U g−1 h−1). Three strains have been found suitable for developing processes for alkaline cellulase production. Soils from Amazonian rain forests are good sources of industrial fungi with particular characteristics. The results of the present study are of commercial and biological interest. Alkaline cellulases may be used in the polishing and washing of denim processing of the textile industry.

Bird Assemblage and Visitation Pattern at Fruiting Elmerrillia tsiampaca (Magnoliaceae) Trees in Papua New Guinea

Most tropical trees produce fleshy fruits that attract frugivores that disperse their seeds. Early demography and distribution for these tree species depend on the effects of frugivores and their behavior. Anthropogenic changes that affect frugivore communities could ultimately result in changes in tree distribution and population demography. We studied the frugivore assemblage at 38 fruiting Elmerrillia tsiampaca, a rain forest canopy tree species in Papua New Guinea. Elmerrillia tsiampaca is an important resource for frugivorous birds at our study site because it produces abundant lipid-rich fruits at a time of low fruit availability. We classified avian frugivores into functional disperser groups and quantified visitation rates and behavior at trees during 56 canopy and 35 ground observation periods. We tested predictions derived from other studies of plant–frugivore interactions with this little-studied frugivore assemblage in an undisturbed rain forest. Elmerrillia tsiampaca fruits were consumed by 26 bird species, but most seeds were removed by eight species. The most important visitors (Columbidae, Paradisaeidae and Rhyticeros plicatus) were of a larger size than predicted based on diaspore size. Columbidae efficiently exploited the structurally protected fruit, which was inconsistent with other studies in New Guinea where structurally protected fruits were predominantly consumed by Paradisaeidae. Birds vulnerable to predation foraged for short time periods, consistent with the hypothesis that predator avoidance enhances seed dispersal. We identified seven functional disperser groups, indicating there is little redundancy in disperser groups among the regular and frequent visitors to this tropical rain forest tree species.

Distribution of Bacillus Thuringiensis in Gunung Jerai Forest (Malaysia)with Insecticidal Activity Against Lepidopteran and Dipteran Insects

Globally there has been a concerted effort to isolate Bt strains from different environments for use as microbial pesticides and in transgenic plants. In our study, 106 soil samples were collected from different altitude in Gunung Jerai forest, an undisturbed rain forest ecosystem, Kedah Darul Aman State, Malaysia. Preliminary screening included temperature selection methods to isolate Bacillus-like colonies, followed by phase contrast microscopy to screen presumptive Bt isolates. Twenty three isolates were selected for PCR analysis with Cry1 general primer (gcry1), PCR to identify the presence of cry1-type genes. Out of 23 isolates, only 17 isolates showed the presence of cry1-type genes with the product size of 558 bp. Subsequently, the 17 Bt isolates which showed the presence of cry1-type genes were subjected to pathotype PCR to predict the insecticidal activity against lepidopteran pests. The results of the pathotype PCR revealed that out of 17 Bt isolates, only 11 isolates showed PCR product indicating their possible anti lepidopteran activity. Plasmid profiling studies indicated the presence of a major plasmid of size 22.5 to 28.5kb.Then the hemolytic positive strains were subjected to one step bioassay against the second instar larvae of Aedes aegypti. One Bt isolate, Bt 02, showed elevated larvicidal activity, which was compared to that of the reference strain Bt.subsp. israelensis. The crystal protein studies of the Bt isolate 02 indicated the presence of cuboidal crystals. SDS-PAGE analysis of the Bt isolate 02 showed a major protein of 101.77 kDa. However, presence of a protein of 32.68 kDa, indicted the possible presence of cytolytic toxin. Finally to study the diversity, two Bt isolates, Bt 22 and Bt 42 were subjected to partial DNA sequencing of the PCR amplicon. The results indicated that these two strains have different nucleotide sequences and each strain showed homology with the reported Bt strains which are also different from each other, thus indicating the presence diverse Bt strains in this environment. The Bt isolates showing anti lepidopteran and anti dipteran activity can be used in integrated pest management to control agricultural pests and to control the selected mosquito vectors.

Density and Diversity of Forest Floor Anurans in the Rain Forests of Southern Western Ghats, India

The structure and composition of forest-floor anuran diversity in the biologically rich rain forests of southern Western Ghats were studied. The study was carried out in the relatively undisturbed rain- forest tract of Kalakad-Mundanthurai Tiger Reserve. A quadrat search method was used to estimate species richness and density of the forest floor anuran community. Sample locations were distributed across three distinct watersheds in the reserve. In total, we captured 509 individuals belonging to 20 species. The density of anurans was 149 individuals ha 21 on the rain-forest floor, and along streams their densities exceeded 300 individuals ha 21 . Total diversity across all watershed locations was partitioned into within and among watershed components, corresponding to alpha and beta diversity. We found high levels of species turnover (high b diversity) among watersheds, a process that may partly explain the high species richness and large number of endemic anuran species known to occur in the rain forests of the Western Ghats. Anurans density was low and comparable to other studies conducted in South-East Asian forests. A re-examination of the reports on anuran densities revealed that Central American anuran densities were an order of magnitude higher than South Asian and South American anuran densities. Existing hypotheses do not adequately explain the differences in anuran densities in different parts of the world.

Spatial Scales of Pollen and Seed-Mediated Gene Flow in Tropical Rain Forest Trees

Gene flow via seed and pollen is a primary determinant of genetic and species diversity in plant communities at different spatial scales. This paper reviews studies of gene flow and population genetic structure in tropical rain forest trees and places them in ecological and biogeographic context. Although much pollination is among nearest neighbors, an increasing number of genetic studies report pollination ranging from 0.5-14 km for canopy tree species, resulting in extensive breeding areas in disturbed and undisturbed rain forest. Direct genetic measures of seed dispersal are still rare; however, studies of fine scale spatial genetic structure (SGS) indicate that the bulk of effective seed dispersal occurs at local scales, and we found no difference in SGS (Sp statistic) between temperate (N=24 species) and tropical forest trees (N=15). Our analysis did find significantly higher genetic differen- tiation in tropical trees (FST=0.177; N=42) than in temperate forest trees (FST=0.116; N=82). This may be due to the fact that tropical trees experience low but significant rates of self-fertilization and bi-parental inbreed- ing, whereas half of the temperate tree species in our survey are wind pollinated and are more strictly allogamous. Genetic drift may also be more pronounced in tropical trees due to the low population densities of most species.

Vegetation and pollen rain relationship from the tropical Atlantic rain forest in Southern Brazil

The relationship between the southern Brazilian tropical Atlantic lowland rain forest and modern pollen rain was studied by pollen traps. The study was carried out on a one hectare plot undisturbed rain forest of the reserve Volta Velha and two secondary forests, ± 50 and 7 years old. About 248 identified tree, shrub and herb species (excluding epiphytes) of 50 families were represented by 126 different pollen and spore types (including non-local taxa). The calculated average influx of pollen rain from the native Atlantic rain forest was 12465 pollen grains per cm² and year. The influx from the ± 50 years old and from the 7 years old secondary forest was relatively low (4112 and 3667 grains per cm² and year, respectively) compared to the undisturbed rain forest. The occurrence of pollen grains of herbs and fern spores were significantly higher in the secondary forests than in the undisturbed rain forest.

Biogeochemical cycling of carbon, water, energy, trace gases, and aerosols in Amazonia: The LBA‐EUSTACH experiments

The biogeochemical cycling of carbon, water, energy, aerosols, and trace gases in the Amazon Basin was investigated in the project European Studies on Trace Gases and Atmospheric Chemistry as a Contribution to the Large‐Scale Biosphere‐Atmosphere Experiment in Amazonia (LBA‐EUSTACH). We present an overview of the design of the project, the measurement sites and methods, and the meteorological conditions during the experiment. The main results from LBA‐EUSTACH are: Eddy correlation studies in three regions of the Amazon Basin consistently show a large net carbon sink in the undisturbed rain forest. Nitrogen emitted by forest soils is subject to chemical cycling within the canopy space, which results in re‐uptake of a large fraction of soil‐derived NOx by the vegetation. The forest vegetation is both a sink and a source of volatile organic compounds, with net deposition being particularly important for partially oxidized organics. Concentrations of aerosol and cloud condensation nuclei (CCN) are highly seasonal, with a pronounced maximum in the dry (burning) season. High CCN concentrations from biomass burning have a pronounced impact on cloud microphysics, rainfall production mechanisms, and probably on large‐scale climate dynamics.

Life on the Leaf Litter: The Ecology ofAnolis nitens tandaiin the Brazilian Amazon

Abstract We studied the ecology of Anolis nitens tandai at three localities in the central and western Amazon of Brazil. The lizards were largely restricted to leaf litter microhabitats in relatively undisturbed rain forest. Activity occurred throughout the day. Body temperatures of active lizards averaged 27.7 ± 0.3 C and were similar to air and substratum temperatures in the microhabitats in which lizards were found. Microhabitats containing lizards were slightly warmer than a random set of microhabitats suggesting that the lizards selected relatively warm sites within a relatively cool forest habitat, but avoidance of treefalls suggests lizards do not seek out the warmest available microhabitats. The diet consisted mostly of grasshoppers, crickets, spiders, and insect larvae. Mean prey size increased with lizard body size, and lizards varied in how full their stomachs were. Sexual dimorphism in mass and limb length exists. Compared with other subspecies of Anolis nitens, A. n. tandai has relatively lon...

The Impact of Habitat Fragmentation on Arthropod Biodiversity

HE decline of biodiversity is accelerated from the degradation, destruction and fragmentation of natural habitats. Field experiments show the consequences of fragmentation on both plants and animals. The ‘‘Biological Dynamics of Forest Fragments Project’’ (BDFFP) was an encompassing biodiversity study conducted in the Brazilian rain forests where stands of 1-, 10- and 100-hectare rain forest fragments were left intact and isolated from the clear-cut landscape. In a study of carrion and dung-feeding beetle communities, Klein (1989) showed that 1- and 10-hectare rain forest fragments, isolated from the contiguous forests by at least 350 meters for two to six years, had fewer species, sparser populations and smaller individuals than beetle communities in undisturbed rain forests. A study of avian species (Bierregaard & Lovejoy 1989) reported that as the rain forests were cut and cleared, birds moved into the remnant forest patches, initially raising the number of individuals. However, after 200 days the number of birds drastically dropped below pre-isolation numbers, with the rate and extent of faunal collapse being greater in smaller reserves than in larger reserves. The amount of time and effort necessary for an experiment like the BDFFP is extensive, so most experimental studies of fragmentation are limited to small habitat patches and attempts are made to extrapolate from them (Shafer 1990). On a smaller scale study, Robinson et al. (1992) recorded the responses of several plant and animal species to habitat fragmentation in pasture grasslands and noted that measures of species diversity did not change with the degree of fragmentation. Although, when looking within a single group, i.e. arthropods, large patches of uncut pasture (5,000 square meters or sq. m) contained a higher diversity of arthropod species (367 species) than medium-sized patches (288 sq. m; 315 species) and small patches (32 sq. m; 303 species).

Use of naturally and anthropogenically disturbed habitats in Amazonian rainforest by the teiid lizard Ameiva ameiva

We studied the effects of natural and anthropogenic habitat disturbances on environmental temperatures and their consequent effects on thermoregulation and habitat use of Ameiva ameiva in a complex habitat matrix of primary tropical forest and several types of disturbed forest in Amazonian Brazil. Data on Ameiva ameiva from other regions in Brazil with habitats that have little canopy coverage are compared with data from rain forest sites to determine if activity of rain forest Ameiva is temporally or spatially limited by the thermal opportunities available in shaded environments. Ameiva ameiva preferentially used disturbed habitats in rain forest regions. These sites had significantly higher environmental temperatures than did surrounding undisturbed rain forest. Environmental temperature distributions indicate that the closed canopy rain forest is a thermally marginal habitat for Ameiva ameiva and that high temperatures resulting from forest clearing are likely to enable Ameiva ameiva to increase foraging activity in adjacent forest edges above what is possible in the continuous interior forest. Ameiva ameiva from rain forest, cerrado and savanna regions of Brazil had significantly lower body temperatures than Ameiva from caatinga, an open habitat type with little canopy coverage. This difference is probably due to high ambient temperatures and the high availability of basking sites in open habitats and suggests a thermal constraint on habitat use and time of activity for Ameiva in closed canopy habitats.

The population status of chameleons within Ranomafana National Park, Madagascar, and recommendations for future monitoring

AbstractMalagasy chameleons are threatened by the relentless pace of habitat destruction. Their great popularity amongst herpetoculturalists has also resulted in collection for international animal markets. Most previous fieldwork has focused on the compilation of much needed species inventories, but little attention has been given to estimating chameleon population densities. This lack of information prevents a reliable assessment of the effects ofhabitat loss and direct exploitation on wild populations. A simple and repeatable methodology for the monitoring of chameleon populations is therefore urgently required. The present study developed survey techniques based on distance sampling within an area of relatively undisturbed rain forest at Ranomafana National Park. In total 394 individuals from six species were recorded and population densities (± SE) of 27.2 ± 5.4/ha Brookesia spp. and 21.4±4.0/ha Calumma spp. were estimated using the computer program DISTANCE. The authors propose that monitoring of chameleons in areas subject to different threats should begin immediately using the methods outlined in this paper.