The islands and associated back channels on the Ohio River, USA, are believed to provide critical habitat features for several wildlife species. However, few studies have quantitatively evaluated habitat quality in th...The islands and associated back channels on the Ohio River, USA, are believed to provide critical habitat features for several wildlife species. However, few studies have quantitatively evaluated habitat quality in these areas. Our main objective was to evaluate the habitat quality of back and main channel areas for several species using habitat suitability index (HSI) models. To test the effectiveness of these models, we attempted to relate HSI scores and the variables measured for each model with measures of relative abundance for the model species. The mean belted kingfisher (Ceryle alcyon) HSI was greater on the main than back channel. However, the model failed to predict kingfisher abundance. The mean reproduction component of the great blue heron (Ardea herodias) HSI, total common muskrat (Ondatra zibethicus) HSI, winter cover component of the snapping turtle (Chelydra serpentina) HSI, and brood-rearing component of the wood duck (Aix sponsa) HSI were all greater on the back than main channel, and were positively related with the relative abundance of each species. We found that island back channels provide characteristics not found elsewhere on the Ohio River and warrant conservation as important riparian wildlife habitat. The effectiveness of using HSI models to predict species abundance on the river was mixed. Modifications to several of the models are needed to improve their use on the Ohio River and, likely, other large rivers.展开更多
Despite its proximity to other well studied islands, Cebu has received little attention from herpetologists, most likely because of early deforestation and the perception very little natural habitat remains for amphib...Despite its proximity to other well studied islands, Cebu has received little attention from herpetologists, most likely because of early deforestation and the perception very little natural habitat remains for amphibians and reptiles. In this study, we present a preliminary assessment of island＇s herpetofauna, focusing our field work on Cebu＇s last remaining forest fragments and synthesizing all available historical museum distribution data. We surveyed amphibians and reptile populations using standardized methods to allow for comparisons between sites and assess sufficiency of sampling effort. Fieldwork resulted in a total of 27 species recorded from five study sites, complementing the 58 species previously known from the island. Together, our data and historical museum records increase the known number of Cebu＇s resident species to 13 amphibians（frogs） and 63 reptiles（lizards, snakes, turtle, crocodile）. We recorded the continued persistence Cebu＇s rare and endemic lizard（Brachymeles cebuensis） and secretive snakes such as Malayotyphlops hypogius, and Ramphotyhlops cumingii, which persist despite Cebu＇s long history of widespread and continuous habitat degradation. Most species encountered, including common and widespread taxa, appeared to persist at low population abundances. To facilitate the immediate recovery of the remaining forest fragments, and resident herpetofauna, conservation effort must be sustained. However, prior to any conservation interventions, ecological baselines must be established to inform the process of recovery.展开更多
DEAR EDITOR：The species-area relationship（SAR）describes the phenomenon whereby the number of plant and animal species found in an area of wild habitat is strongly correlated with the size of that area.As one of the...DEAR EDITOR：The species-area relationship（SAR）describes the phenomenon whereby the number of plant and animal species found in an area of wild habitat is strongly correlated with the size of that area.As one of the few ecological laws,the SAR plays a vital role in the design and assessment of biodiversity protection regions（Lomolino et al,2010;Ladle＆Whittaker,2011）.Increasing area and habitat promote species richness（Triantis et al,2003）and both these mechanisms have展开更多
The decline of barn swallow populations may be mainly caused by the reduction of their foraging habitat. A clear understanding of the links between proportions of available and used microhabitats of foraging barn swal...The decline of barn swallow populations may be mainly caused by the reduction of their foraging habitat. A clear understanding of the links between proportions of available and used microhabitats of foraging barn swallows in farmland, estuary, and island habitats would enhance our understanding of the foraging habitat requirements of this species and on the effects of anthropogenic activities, such as habitat conversion (e.g., land to water, crop fields to non-arable land), on their distribution. We hypothesized that: 1) foraging swallows would be more abundant in the most common microhabitat;and 2) swallow abundance would decrease with increased foraging distance from the nest-site. As predicted by our first hypothesis, swallows were more abundant in the most common microhabitat (i.e., crop fields in farmland and non-arable land on the island). Our data also support our second hypothesis that increased foraging distances from the nest-site negatively affected foraging swallow abundance. In summary, barn swallows foraged in the habitats most convenient to nest-sites, however, management of agricultural lands should include non-arable lands in the composition of available foraging microhabitats.展开更多
城市中的园林绿地呈现斑块状分布,其栖息地特征与岛屿栖息地相似。2008年11月至2009年10月,对上海市闵行区内的7块城市绿地进行调查,记录雀形目鸟类的分布情况,并运用Nestedness temperature calculator软件,检验其群落结构是否符合嵌...城市中的园林绿地呈现斑块状分布,其栖息地特征与岛屿栖息地相似。2008年11月至2009年10月,对上海市闵行区内的7块城市绿地进行调查,记录雀形目鸟类的分布情况,并运用Nestedness temperature calculator软件,检验其群落结构是否符合嵌套结构。运用Arc GIS软件分析该地区的卫星图片,收集7块样地的面积、绿地盖度、水源距离和人为干扰程度等数据,结合实地调查所得到的数据,分析这一嵌套结构的形成原因和影响因素。调查结果显示:上海市闵行区城市绿地中的雀形目鸟类分布是显著的嵌套结构,矩阵系统温度是21.78℃,填充度41.3%。7块样地中出现的物种数从14种到38种不等。其中,白鹡鸰(Motacilla alba)等11种鸟在7块样地中都有分布,黑卷尾(Dicrurusmacrocerus)等9种鸟类只在一个样地中出现过。园林面积、绿地面积和水源情况都对其嵌套结构有显著影响。但与真正岛屿上存在的群落分布嵌套结构不同,人为干扰程度对这一结构也有非常明显的影响。上述结果表明,影响上海闵行区园林鸟类群落嵌套结构的主要原因是栖息地结构和人为干扰程度。因此,建议在规划和建设城市公园和绿地时,应该偏重于面积较大,植被盖度和丰富度高,结构合理的园林,并尽量减少人为干扰对鸟类栖息地的影响。展开更多
文摘The islands and associated back channels on the Ohio River, USA, are believed to provide critical habitat features for several wildlife species. However, few studies have quantitatively evaluated habitat quality in these areas. Our main objective was to evaluate the habitat quality of back and main channel areas for several species using habitat suitability index (HSI) models. To test the effectiveness of these models, we attempted to relate HSI scores and the variables measured for each model with measures of relative abundance for the model species. The mean belted kingfisher (Ceryle alcyon) HSI was greater on the main than back channel. However, the model failed to predict kingfisher abundance. The mean reproduction component of the great blue heron (Ardea herodias) HSI, total common muskrat (Ondatra zibethicus) HSI, winter cover component of the snapping turtle (Chelydra serpentina) HSI, and brood-rearing component of the wood duck (Aix sponsa) HSI were all greater on the back than main channel, and were positively related with the relative abundance of each species. We found that island back channels provide characteristics not found elsewhere on the Ohio River and warrant conservation as important riparian wildlife habitat. The effectiveness of using HSI models to predict species abundance on the river was mixed. Modifications to several of the models are needed to improve their use on the Ohio River and, likely, other large rivers.
基金project “Expanding and Diversifying the National System of Protected Areas of the Philippines” with support from Global Environment Facility (GEF) and United Nations Development Programme (UDNP)During the preparation of this manuscript, RMB was supported by NSF DEB 0743491 and 1418895
文摘Despite its proximity to other well studied islands, Cebu has received little attention from herpetologists, most likely because of early deforestation and the perception very little natural habitat remains for amphibians and reptiles. In this study, we present a preliminary assessment of island＇s herpetofauna, focusing our field work on Cebu＇s last remaining forest fragments and synthesizing all available historical museum distribution data. We surveyed amphibians and reptile populations using standardized methods to allow for comparisons between sites and assess sufficiency of sampling effort. Fieldwork resulted in a total of 27 species recorded from five study sites, complementing the 58 species previously known from the island. Together, our data and historical museum records increase the known number of Cebu＇s resident species to 13 amphibians（frogs） and 63 reptiles（lizards, snakes, turtle, crocodile）. We recorded the continued persistence Cebu＇s rare and endemic lizard（Brachymeles cebuensis） and secretive snakes such as Malayotyphlops hypogius, and Ramphotyhlops cumingii, which persist despite Cebu＇s long history of widespread and continuous habitat degradation. Most species encountered, including common and widespread taxa, appeared to persist at low population abundances. To facilitate the immediate recovery of the remaining forest fragments, and resident herpetofauna, conservation effort must be sustained. However, prior to any conservation interventions, ecological baselines must be established to inform the process of recovery.
基金supported by the National Natural Science Foundation of China(31170397)
文摘DEAR EDITOR：The species-area relationship（SAR）describes the phenomenon whereby the number of plant and animal species found in an area of wild habitat is strongly correlated with the size of that area.As one of the few ecological laws,the SAR plays a vital role in the design and assessment of biodiversity protection regions（Lomolino et al,2010;Ladle＆Whittaker,2011）.Increasing area and habitat promote species richness（Triantis et al,2003）and both these mechanisms have
文摘The decline of barn swallow populations may be mainly caused by the reduction of their foraging habitat. A clear understanding of the links between proportions of available and used microhabitats of foraging barn swallows in farmland, estuary, and island habitats would enhance our understanding of the foraging habitat requirements of this species and on the effects of anthropogenic activities, such as habitat conversion (e.g., land to water, crop fields to non-arable land), on their distribution. We hypothesized that: 1) foraging swallows would be more abundant in the most common microhabitat;and 2) swallow abundance would decrease with increased foraging distance from the nest-site. As predicted by our first hypothesis, swallows were more abundant in the most common microhabitat (i.e., crop fields in farmland and non-arable land on the island). Our data also support our second hypothesis that increased foraging distances from the nest-site negatively affected foraging swallow abundance. In summary, barn swallows foraged in the habitats most convenient to nest-sites, however, management of agricultural lands should include non-arable lands in the composition of available foraging microhabitats.
文摘城市中的园林绿地呈现斑块状分布,其栖息地特征与岛屿栖息地相似。2008年11月至2009年10月,对上海市闵行区内的7块城市绿地进行调查,记录雀形目鸟类的分布情况,并运用Nestedness temperature calculator软件,检验其群落结构是否符合嵌套结构。运用Arc GIS软件分析该地区的卫星图片,收集7块样地的面积、绿地盖度、水源距离和人为干扰程度等数据,结合实地调查所得到的数据,分析这一嵌套结构的形成原因和影响因素。调查结果显示:上海市闵行区城市绿地中的雀形目鸟类分布是显著的嵌套结构,矩阵系统温度是21.78℃,填充度41.3%。7块样地中出现的物种数从14种到38种不等。其中,白鹡鸰(Motacilla alba)等11种鸟在7块样地中都有分布,黑卷尾(Dicrurusmacrocerus)等9种鸟类只在一个样地中出现过。园林面积、绿地面积和水源情况都对其嵌套结构有显著影响。但与真正岛屿上存在的群落分布嵌套结构不同,人为干扰程度对这一结构也有非常明显的影响。上述结果表明,影响上海闵行区园林鸟类群落嵌套结构的主要原因是栖息地结构和人为干扰程度。因此,建议在规划和建设城市公园和绿地时,应该偏重于面积较大,植被盖度和丰富度高,结构合理的园林,并尽量减少人为干扰对鸟类栖息地的影响。
