Reptile Habitat Research Articles

농업경관 내 연못형습지의 생태계서비스 평가를 위한 기능 설정 연구

연못형습지(Pond Wetland)는 우리나라 농업경관에서 많이 분포하고 있다. 이러한 연못형습지는 생물다양성을 위한 중요한 자원으로 평가 받는다. 하지만 연못형습지(Pond Wetland)에 대한 연구는 유형분류에 그치고 있다. 따라서 본 연구는 연못형습지의 생태계서비스(Ecosystem Service) 기능을 알아보았다. 연구방법은 총 3단계로 기능분석, 기능도출, 중요도 분석의 순으로 진행하였다. 선행연구를 분석하여 총 22가지의 기능을 도출하였다. 전문가 설문 결과 22개 항목 중 생물, 환경, 사회문화 분야에 각 4 기능씩 총 12개 기능으로 선별하였다. 항목간 AHP(Analytic Hierarchy Process)를 실시하여 기능별 중요도를 산출하였다. 중복된 기능은 통합하여 연못형습지의 생태계서비스 기능 10가지(1. Water Storage & Irrigation, 2. Vegetation Diversity, 3. Amphibian & Reptile Habitat, 4. Water Purification, 5. Aquatic Insect Habitat, 6. Nutriments Control, 7. Groundwater Recharge, 8. Fishery Habitat, 9. Eco-Experience & Education, 10. Aesthetic landscape)를 도출하였다. 향후 기능별 중요도 분석과 경제적 가치 지표를 적용하여 연못형습지의 생태계서비스 평가에 활용 할 수 있을 것으로 판단된다. A lot of Pond Wetland (Palustrine Wetland) are distributed in agricultural landscapes, Korea. These wetlands are evaluated as important resources for conservation of biodiversity. However, the study of Pond Wetland is rarely conducted except type classification in Korea. In this study, the function of pond wetland as ecosystem services is studied for conservation and utilization of wetland. Research was conducted in three steps; functionality analysis, functionality derivation, and importance analysis. A total of 22 features were derived by analyzing the previous studies. As a result of expert survey, 4 features were selected by each in the field of biological, environmental, and socio-culture among the 22 features. Importance was calculated by conducting a cross-functional features using Analytic Hierarchy Process (AHP). Finally, 10 ecosystem service functions of pond wetland were derived through expert survey; (1) Water Storage & Irrigation, (2) Vegetation Diversity, (3) Amphibian & Reptile Habitat, (4) Water Purification, (5) Aquatic Insect Habitat, (6) Nutriments Control was derived, (7) Groundwater Recharge, (8) Fishery Habitat, (9) Eco-Experience & Education, and (10) Aesthetic landscape. It is expected that this study is able to utilize in evaluation of pond wetlands ecosystem services by further study on analysis of functional importance and economic value index.

Designing for conservation outcomes: the value of remnant habitat for reptiles on ski runs in subalpine landscapes

Subalpine ecosystems are centres of endemism that are important for biodiversity. However, these areas are under threat from the creation, expansion and continued modification of ski runs, activities that have largely negative effects on wildlife. Despite this threat, research on the impacts of ski runs is limited for reptiles—particularly regarding the value of remnant vegetation retained on ski runs. Here we quantify the effects of habitat loss and fragmentation (i.e., patch size, patch isolation and edge effects) on the abundance of a common subalpine lizard and on thermal regimes (a key determinant of lizard distribution) in an Australian ski resort. The number of lizards observed differed significantly with habitat type (ski runs vs. forested areas) and patch isolation, but not patch size. In addition, the edges of patches supported more lizards than any other habitat type. These patterns of lizard distribution can be explained, in part, by the differing thermal regimes in each habitat. Ski runs had significantly higher ground surface temperatures than any other habitat type, precluding their use for a considerable proportion of the activity period of a lizard. In comparison, edges were characterised by lower temperatures than ski runs, but higher temperatures than the core of forested areas, potentially providing a favourable environment for thermoregulation. Based on our results, we conclude that although modified ski runs have a negative effect on lizards, patches of remnant vegetation retained on ski runs are of value for reptiles and their conservation could help mitigate the negative effects of habitat loss caused by ski run creation.

Taxonomic and functional response of a Mediterranean reptile assemblage to a repeated fire regime

Wildfires are common disturbances that have a major impact on ecosystems. Recent decades have seen an increase in fire frequency and extension due to the combined effects of climate change and land-use history. We studied the taxonomic and functional response of a reptile assemblage to repeated fires in southern France to understand shifts in dominant species and diversity, as well as the mechanisms that underlie responses according to functional traits of species. In the spring of 2010, we sampled reptiles in areas with three types of fire regime: unburned, burned once (2003) and burned 4–5 times (last fire in 2003) along a fire history of 51-years period. With this field sampling design, we examined the intermediate disturbance hypothesis and the habitat accommodation model of succession as methods to predict reptile responses to natural fire regimes. We also compared habitat structure at the study area between 1944 and 2006 to certify that repeated-fire regimes have modified the habitat for reptiles. The comparison of the habitat structure between both periods demonstrated that repeated-fire regimes modified the landscape from a homogeneous sparse forest to a contrasted heterogeneous mixture of scrubland and dense forest. We found a loss of reptile diversity after one and multiple fires, a result that contradicts the intermediate disturbance hypothesis. Reptile composition differed among the three fire regimes: there was a shift in dominant species and a reduction of beta diversity related to an increase in the number of fires. We also observed a functional response to repeated fires, with an increased frequency of insectivorous reptiles, which live in open areas, are specialists in their ecological niche, and have a short lifespan. These results suggest that reptile replacement according to fire regime accounts for a habitat accommodation model following particular traits of species. Our study indicated that areas subjected to repeated fires have a more strictly Mediterranean reptile assemblage than unburned areas, due to the ability of Mediterranean species to survive thermal environments in open (burned) areas. At a regional scale, changes in dominant species between unburned and repeatedly burned areas might be an argument for maintaining a patchwork of areas burned at variable intervals. However, the increase in fire frequency and extension suggests a future scenario of extinction for species negatively impacted by fire, such as the endangered Hermann’s tortoise Testudo hermanni, for which the study area is home to one of the last native populations in the western Mediterranean.

Is the reptile community affected by Eucalyptus wandoo tree condition?

Context Large portions of the world’s forests and woodlands are currently affected by declines in canopy condition of dominant tree species; however, the effects of these declines on faunal communities are largely unknown. Eucalyptus wandoo woodlands in the south-west region of Western Australia have demonstrated declines in condition since the early 1990s. Such declines in tree condition can result in reduced understorey vegetation, increased leaf-litter cover and coarse woody debris, potentially altering the habitat and resource available to reptiles. Prescribed fire events, another mechanism of habitat change for reptiles, are a common occurrence in these woodlands. Aims The present research investigated whether reptile communities were influenced by E. wandoo tree condition, and the changes in the habitat associated with E. wandoo decline. Methods Reptile trapping was conducted at 24 E. wandoo-dominated sites (of varying condition) in Dryandra State Forest and Wandoo Conservation Park, Western Australia. Overall, reptile abundance, species richness and individual reptile species abundances (only those species captured in sufficient numbers for analysis) were compared with a range of habitat characteristics that are likely to be altered by changes in E. wandoo tree condition. Key results Overall, higher reptile abundance and species richness were observed at sites with longer time since fire and more site litter cover. There was also a greater abundance and diversity of reptiles at sites where E. wandoo trees exhibited fewer symptoms of tree decline. Similar analyses for the five most common skink species indicated species-specific relationships with tree-condition measures, time since last fire, site litter cover, distance to drift fence from E. wandoo trees, understorey vegetation density and the density of coarse woody debris. Conclusions Abundance and species diversity of the reptile communities in E. wandoo woodlands were strongly related to time since last fire, E. wandoo tree condition and habitat characteristics such as site litter cover and the density of coarse woody debris. Implications Decline in the condition of E. wandoo trees and the fire events in E. wandoo woodlands are both mechanisms of change correlated with reptile habitat and resources. Future management of E. wandoo woodlands may include reducing prescribed fire events in areas demonstrating symptoms of tree decline, to conserve reptile abundance and species richness.

Forest‐fire regimes affect thermoregulatory opportunities for terrestrial ectotherms

AbstractFire‐induced changes in canopy openness may affect sunlight penetration to the forest floor, and thus the operative temperatures available to terrestrial ectotherms. We examined thermal regimes for two types of ectotherms: diurnally active species that utilize sun‐exposed patches to regulate their body temperatures, and nocturnally active species that depend upon solar radiation striking the rocks under which they shelter. We measured canopy openness, shrub height, radiation transmission and operative environmental temperatures in the open and inside reptile retreat‐sites, at 24 study sites in eucalypt forests in two regions (Gosford and Yengo) in south‐eastern Australia. All sites were last burnt in 2000–2001, but had experienced different fire frequencies (1–4 fires over the previous 37 years). In Gosford, higher fire frequencies reduced canopy openness and radiation transmission at ground and shrub level, and thus reduced environmental temperatures and the thermal quality of reptile habitats. Our modelling based on thermal preferenda of an endangered snake species (the broad‐headed snake Hoplocephalus bungaroides) suggests that increased fire frequency at Gosford halved the amount of time an animal could spend within its preferred (set‐point) range, regardless of whether it thermoregulated beneath rocks or basked out in the open. At Yengo, however, fire frequency did not affect the thermal quality of reptile habitats. Thus, the effects of fire frequency on forest structure and the thermal environment at ground level differed between adjacent areas, and relatively small changes in canopy openness translated into major effects on thermoregulatory opportunities for reptiles. Although fire is a useful management tool for creating open habitats, we need to understand more about the effects of fire frequency on vegetation structure and thermal environment before we can use fire to manage habitats for reptiles.

Urbanization effects on watershed habitat potential: a multivariate assessment of thresholds and interactions

AbstractA watershed‐based assessment is used to assess the effect of urbanization on vertebrate habitat potential in Westfield River Watershed in Massachusetts, USA. A spatial analysis is used to develop urban indicators and habitat potential for each subbasin in the watershed. It is observed that threshold effect of urbanization on habitat potential of vertebrates is at 10 to 12 percent impervious cover. Amphibian habitat is influenced by available open space and land use disturbance in the watershed. The reptile habitat is sensitive to impervious coverage and land use disturbance, and decreased with fragmentation. The habitat for birds is influenced by land use disturbance, human population densities, size of forest patch, and open space in the watershed. Mammal habitat is influenced by human population density, land use disturbance, and fragmentation. A watershed‐based assessment is useful to identify critical areas of high urban influence. Threshold values and nature of interactions between urbanization and habitat are assessed and used in policy recommendations. Policies and practices that minimize effects of urbanization in the watershed include impervious taxes, zoning policies, and open space protection. The need for provision of education and information on the relationship between urbanization and habitat potential is emphasized for sustainable use of watershed resources. Copyright © 2009 John Wiley & Sons, Ltd.

A NEW ENDEMIC SPECIES OF LIOLAEMUS (IGUANIA: LIOLAEMIDAE) FROM THE MOUNTAIN RANGE OF TANDILIA, BUENOS AIRES PROVINCE, ARGENTINA

Liolaemus gracilis was cited in the categorization of the reptile habitat associations of Buenos Aires province in Argentina as the only Liolaemus lizard inhabiting the rocky grounds of the Tandilia System. We describe a new species of the genus Liolaemus which was previously confused with the widely ranging L. gracilis from the population of this mountain range. We examined samples of populations from coastal sand dunes and from the mountain range of Tandilia. Morphological characters and measurements were taken from specimens of both populations. We recorded ecological and life history notes of the saxicolous form in the field. The new species is an endemic and saxicolous form from Tandilia that can be distinguished from L. gracilis by indistinct or absent light dorsolateral stripes, small and segmental paravertebral spots, and by a throat with a denser, fine and diffuse spotted pattern. The ventral coloration is grayish plumb. Temporal scales are keeled or slightly keeled and the auricular scale is less differentiated. Morphometrically, the new species is larger in snout–vent length and head width but smaller in maximum body width and tail length than L. gracilis. The new species is oviparous and insectivorous.

Mine-drainage treatment wetland as habitat for herptofaunal wildlife

Land reclamation techniques that incorporate habitat features for herptofaunal wildlife have received little attention. We assessed the suitability of a wetland, constructed for the treatment of mine-water drainage, for supporting herptofaunal wildlife from 1988 through 1990 using diurnal and nocturnal surveys. Natural wetlands within the surrounding watershed were also monitored for comparison. The treatment wetland supported the greatest abundance and species richness of herptofauna among the sites surveyed. Abundance was a function of the frog density, particularly green frogs (Rana clamitans) and pickerel frogs (R. palustris), while species richness was due to the number of snake species found. The rich mix of snake species present at the treatment wetland was believed due to a combination of an abundant frog prey base and an amply supply of den sites in rock debris left behind from earlier surface-mining activities. Nocturnal surveys of breeding male frogs demonstrated highest breeding activity at the treatment wetland, particularly for spring peepers (Hyla crucifer). Whole-body assays of green frog and bullfrog (R. catesbeiana) tissues showed no differences among sites in uptake of iron, aluminum, and zinc; managanese levels in samples from the treatment wetland were significantly lower than those from natural wetlands. These results suggest that wetlands established for water quality improvement can provide habitat for reptiles and amphibians, with the species composition dependent on the construction design, the proximity to source populations, and the degree of acidity and heavy-metal concentrations in drainage waters.

An assessment of the importance of heathlands as habitats for reptiles

SPELLERBERG, I. F., 1989. An assessment of the importance of heathlands as habitats for reptiles. Britain has a species-poor reptile fauna of six species. Although they occur in association with various types of plant communities, most species seem to be associated with heathlands. The lizard Lacerta agilis is particularly associated with heathlands but data presented here suggests that the vegetation structure of typical, undisturbed, lowland heathlands is less suitable for this species than disturbed heathland with more structural diversity.

Forest Habitat for Reptiles & Amphibians of the Northeast

Forest Habitat for Reptiles & Amphibians of the Northeast