bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sandy beaches at the brink
Authors: Schlacher Thomas A. , Dugan Jenifer , Schoeman Dave S. , Lastra Mariano , Jones Alan , Scapini Felicita , McLachlan Anton , Defeo Omar 
Published: February 2009

ABSTRACTSandy beaches line most of the world's oceans and are highly valued by society: more people use sandy beaches than any other type of shore. While the economic and social values of beaches are generally regarded as paramount, sandy shores also have special ecological features and contain a distinctive biodiversity that is generally not recognized. These unique ecosystems are facing escalating anthropogenic pressures, chiefly from rapacious coastal development, direct human uses — mainly associated with recreation — and rising sea levels. Beaches are increasingly becoming trapped in a ‘coastal squeeze’ between burgeoning human populations from the land and the effects of global climate change from the sea. Society's interventions (e.g. shoreline armouring, beach nourishment) to combat changes in beach environments, such as erosion and shoreline retreat, can result in severe ecological impacts and loss of biodiversity at local scales, but are predicted also to have cumulative large‐scale consequences worldwide. Because of the scale of this problem, the continued existence of beaches as functional ecosystems is likely to depend on direct conservation efforts. Conservation, in turn, will have to increasingly draw on a consolidated body of ecological theory for these ecosystems. Although this body of theory has yet to be fully developed, we identify here a number of critical research directions that are required to progress coastal management and conservation of sandy beach ecosystems.
Spatial scale and evolutionary history determine the degree of taxonomic homogenization across island bird assemblages
Authors: Cassey Phillip , Lockwood Julie L. , Blackburn Tim M. , Olden Julian D. 
Published: February 2009

ABSTRACTIt is widely documented that human activities have elevated the extirpation of natural populations as well as the successful introduction to new areas of non‐native species. These dual processes of introduction and extirpation can change the similarity of communities, but the direction and magnitude these changes take are likely to depend on the manner in which introductions and extirpations occur, the spatial scale at which the changes are measured, and the initial similarity of the communities before the human‐induced drivers occurred. Here, we explore patterns of extirpation and introduction and their influence on the similarity of global oceanic island bird assemblages from four different Oceans (Atlantic, Caribbean, Indian, Pacific). We show that different historical patterns of introduction and extirpation have produced varying trends in compositional similarity both between islands within archipelagos and between islands across different archipelagos within the same ocean. Patterns of bird assemblage convergence (i.e. taxonomic homogenization) or divergence (i.e. taxonomic differentiation) among islands depended on the scale of examination, the evolutionary associations among species of the region, and the cultural history of human colonization. These factors are all likely to be leading to a series of multiple interacting processes that are shaping the complex compositional changes observed among global island bird faunas over time.
Squamate richness in the Brazilian Cerrado and its environmental–climatic associations
Authors: Costa Gabriel C. , Nogueira Cristiano , Machado Ricardo B. , Colli Guarino R. 
Published: February 2009

ABSTRACTWe investigate patterns of species richness of squamates (lizards, snakes, and amphisbaenians) in the Brazilian Cerrado, identifying areas of particularly high richness, and testing predictions of large‐scale richness hypotheses by analysing the relationship between species richness and environmental climatic variables. We used point localities from museum collections to produce maps of the predicted distributions for 237 Cerrado squamate species, using niche‐modelling techniques. We superimposed distributions of all species on a composite map, depicting richness across the ecosystem. Then, we performed a multiple regression analysis using eigenvector‐based spatial filtering (Principal Coordinate of Neighbour Matrices) to assess environmental–climatic variables that are best predictors of species richness. We found that the environmental–climatic and spatial filters multiple regression model explained 78% of the variation in Cerrado squamate richness (r2 = 0.78; F = 32.66; P < 0.01). Best predictors of species richness were: annual precipitation, precipitation seasonality, altitude, net primary productivity, and precipitation during the driest quarter. A model selection approach revealed that several mechanisms related to the different diversity hypothesis might work together to explain richness variation in the Cerrado. Areas of higher species richness in Cerrado were located mainly in the south‐west, north, extreme east, and scattered areas in the north‐west portions of the biome. Partitioning of energy among species, habitat differentiation, and tolerance to variable environments may be the primary ecological factors determining variation in squamate richness across the Cerrado. High richness areas in northern Cerrado, predicted by our models, are still poorly sampled, and biological surveys are warranted in that region. The south‐western region of the Cerrado exhibits high species richness and is also undergoing high levels of deforestation. Therefore, maintenance of existing reserves, establishment of ecological corridors among reserves, and creation of new reserves are urgently needed to ensure conservation of species in these areas.
Introduction history and invasion success in exotic vines introduced to Australia
Authors: Harris Carla J. , Murray Brad R. , Hose Grant C. , Hamilton Mark A. 
Published: February 2009

ABSTRACTThe ecological damage caused by invasive vines poses a considerable threat to many natural ecosystems. However, very little data are available for this potentially environmentally destructive functional group in Australia. In order to address this paucity of information, we assembled the first inventory of exotic vines that have become established in natural ecosystems across Australia. The influence that introduction history attributes, variables that relate to the introduction of a species to a new area, may have on the occurrence and distribution of exotic vines was also determined. We asked whether the continent of origin, reason for introduction, and residence time related to the prevalence and distribution of exotic vines across Australia. A total of 179 exotic climbing plant species from 40 different families were found to have become established across continental Australia. However, five families accounted for over 50% of these species. Most exotic vines originated from South America, and were introduced for ornamental purposes. The length of time in which an exotic vine had been present in its new range was significantly related to its distribution, with a positive relationship found between residence time and area of occupancy across the continent. No other introduction history attribute was significantly related to the area of occupancy, or distribution, of a species. This suggests that while the trends found among introduction history attributes are important in explaining the prevalence of exotic vines in Australia, only residence time is currently a useful predictor of their future success.
Priority sites for conservation of land snails in Gabon: testing the umbrella species concept
Authors: Fontaine Benoît , Gargominy Olivier , Neubert Eike 
Published: February 2009

ABSTRACTIn order to assess the potential for molluscan conservation of a protected area considered representative of regional megafauna, we sampled molluscs inside and outside Lopé National Park in Gabon. In the northern part of Lopé National Park, 116 stations were surveyed and 71 species collected. Outside the park, 37 stations yielded 96 species, including 71 in Lastoursville, a small limestone area where molluscs are significantly more abundant than in other collecting sites. Lastoursville is among the richest sites known for molluscs in Africa. Overlap between sampling areas was limited, with 20.0% of the species found only in Lopé National Park, and 40.8% of the species found only outside. This suggests that Lopé National Park does not protect the whole molluscan diversity of central Gabon. Given the high levels of allopatric diversity of tropical land snails, conservation strategies cannot be the same for snails and for wide‐ranging vertebrates. Protecting small areas with a high abundance and diversity of molluscs would be less expensive and as efficient for molluscan conservation as protecting large tracts of rainforest. Despite limited general knowledge of central African molluscs, robust estimates of site‐specific diversity can be produced. Limestone areas harbour a remarkable biodiversity: sites such as Lastoursville would be ideal candidates for small protected areas dedicated to the conservation of land snails, and would complement the role of large protected areas.
Prediction and validation of the potential global distribution of a problematic alien invasive species — the American bullfrog
Authors: Ficetola Gentile Francesco , Thuiller Wilfried , Miaud Claude 
Published: February 2009

ABSTRACTPredicting the probability of successful establishment and invasion of alien species at global scale, by matching climatic and land use data, is a priority for the risk assessment. Both large‐ and local‐scale factors contribute to the outcome of invasions, and should be integrated to improve the predictions. At global scale, we used climatic and land use layers to evaluate the habitat suitability for the American bullfrogRana catesbeiana, a major invasive species that is among the causes of amphibian decline. Environmental models were built by using Maxent, a machine learning method. Then, we integrated global data with information on richness of native communities and hunting pressure collected at the local scale. Global‐scale data allowed us to delineate the areas with the highest suitability for this species. Predicted suitability was significantly related to the invasiveness observed for bullfrog populations historically introduced in Europe, but did not explain a large portion of variability in invasion success. The integration of data at the global and local scales greatly improved the performance of models, and explained > 57% of the variance in introduction success: bullfrogs were more invasive in areas with high suitability and low hunting pressure over frogs. Our study identified the climatic factors entailing the risk of invasion by bullfrogs, and stresses the importance of the integration of biotic and abiotic data collected at different spatial scales, to evaluate the areas where monitoring and management efforts need to be focused.
Invasive plants and their ecological strategies: prediction and explanation of woody plant invasion in New England
Authors: Herron Patrick M. , Martine Christopher T. , Latimer Andrew M. , Leicht‐Young Stacey A. 
Published: February 2009

AbstractEffective management of introduced species requires the early identification of species that pose a significant threat of becoming invasive. To better understand the invasive ecology of species in New England, USA, we compiled a character data set with which to compare non‐native species that are known invaders to non‐native species that are not currently known to be invasive. In contrast to previous biological trait‐based models, we employed a Bayesian hierarchical analysis to identify sets of plant traits associated with invasiveness for each of three growth forms (vines, shrubs, and trees). The resulting models identify a suite of ‘invasive traits’ highlighting the ecology associated with invasiveness for each of three growth forms. The most effective predictors of invasiveness that emerged from our model were ‘invasive elsewhere’, ‘fast growth rate’, ‘native latitudinal range’, and ‘growth form’. The contrast among growth forms was pronounced. For example, ‘wind dispersal’ was positively correlated with invasiveness in trees, but negatively correlated in shrubs and vines. The predictive model was able to correctly classify invasive plants 67% of the time (22/33), and non‐invasive plants 95% of the time (204/215). A number of potential future invasive species in New England that deserve management consideration were identified.
Plant families as predictors of plant biodiversity in Mexico
Authors: Villaseñor José Luis , Maeda Pedro , Rosell Julieta A. , Ortiz Enrique 
Published: February 2009

ABSTRACTThree speciose plant families (Asteraceae, Fabaceae s.l., and Poaceae) are evaluated for their appropriateness as predictors of overall regional patterns of plant diversity in Mexico. These families fulfil criteria for usefulness as indicators advocated by several authors, such as adequate taxonomic knowledge, wide geographical distribution, and occurrence in different plant communities. Known richness was determined from a database including 17,903 species from floristic inventories, review of taxonomic literature, and the study of herbarium specimens. Mexico was divided into 253 cells, each 1° latitude by 1° longitude; for each cell, total plant diversity and number of species in each predictor's family were determined. In addition, each species was categorized by ‘preferred’ vegetation type (temperate forest, dry tropical forest, humid tropical forest, xerophytic scrubland). Both multiple and simple regression models show that the three families are good predictors of total vascular floristic richness. Fabaceae s.l. has the highest semipartial correlations for all multiple models except with the xerophytic scrubland data set, for which it shares the highest values with Poaceae. Univariate models also predict satisfactorily the vascular floristic richness, especially when Fabaceae s.l. is used as the predictor, and the effect of vegetation type is included. Our results indicate that these three families can be used as potential predictors for total vascular plant species richness in Mexico although Fabaceae s.l. is the best predictor.
La Niña's signature: synchronous decline of the mammal community in a ‘protected’ area in India
Authors: Waite T. A. , Campbell L. G. , Chhangani A. K. , Robbins P. 
Published: February 2009

AbstractMounting evidence indicates large‐scale climatic phenomena such as El Niño Southern Oscillation (ENSO) can overwhelm endogenous factors that govern the population dynamics of wild species. We add to this evidence by documenting an ENSO‐related decline of large mammals in the Kumbhalgarh Wildlife Sanctuary, in Rajasthan, India. This event coincided with the drought of 2000, following two consecutive monsoon failures. Time series of biennial counts (1991–2005) shared a common feature: all 13 species declined in abundance from 1999 to 2001, with 11 species experiencing an apparent decline exceeding 25%. An ENSO index explained much of the variability in population size, apparently reflecting mass mortality and/or recruitment failure caused by the major 1998–2000 La Niña event, followed by a rapid rebound. ENSO apparently overwhelmed endogenous factors and synchronized the dynamics of the mammalian community. Our findings may prove to be symptomatic of geographically broad impacts of large‐scale climate on the dynamics of terrestrial vertebrate communities, even in protected areas. Our findings reinforce the growing recognition that we should not overlook global‐scale causal agents of ecological change.
Modelling ecological niches from low numbers of occurrences: assessment of the conservation status of poorly known viverrids (Mammalia, Carnivora) across two continents
Authors: Papeş M. , Gaubert P. 
Published: February 2009

ABSTRACTThe conservation of poorly known species is difficult because of incomplete knowledge on their biology and distribution. We studied the contribution of two ecological niche modelling tools, the Genetic Algorithm for Rule‐set Prediction (GARP) and maximum entropy (Maxent), in assessing potential ranges and distributional connectivity among 12 of the least known African and Asian viverrids. The level of agreement between GARP and Maxent predictions was low when < 15 occurrences were available, probably indicating a minimum number below that necessary to obtain models with good predictive power. Unexpectedly, our results suggested that Maxent extrapolated more than GARP in the context of small sample sizes. Predictions were overlapped with current land use and location of protected areas to estimate the conservation status of each species. Our analyses yielded range predictions generally contradicting with extents of occurrence established by the IUCN. We evidenced a high level of disturbance within predicted distributions in West and East Africa, Sumatra, and South‐East Asia, and identified within West African degraded lowlands four relatively preserved areas that might be of prime importance for the conservation of rainforest taxa. Knowing whether these species of viverrids may survive in degraded or alternative habitats is of crucial importance for further conservation planning. The level of coverage of species suitable ranges by existing and proposed IUCN reserves was low, and we recommend that the total surface of protected areas be substantially increased on both continents.
Bryophyte diversity and distribution along an altitudinal gradient on a lava flow in La Réunion
Authors: Ah‐Peng Claudine , Chuah‐Petiot Min , Descamps‐Julien Blandine , Bardat Jacques , Stamenoff Pierre , Strasberg Dominique 
Published: February 2009

ABSTRACTNon‐vascular plant distribution patterns were examined in three microhabitats along an altitudinal gradient on a recent lava flow of the Piton de la Fournaise volcano (La Réunion, Mascarene archipelago). The uniform nature of the lava flow provides an excellent system to study the relationship between altitude and species diversity and distribution, and at the same time avoiding confusing multiple effects of substrate and vegetation heterogeneity. Non‐vascular plants were surveyed with quadrats within an altitudinal range from 250 m to 850 m a.s.l. Fine‐scale variations in bryophyte communities between three ecological microhabitats (the ground and on the rachises of two fern species) were investigated. Three specific questions were addressed: (1) What is the species diversity of bryophyte communities on a 19‐year‐old lava flow? (2) How does altitude influence the diversity and distribution of bryophytes on a lava flow? (3) Does microhabitat variation control bryophyte diversity? In our study, bryophyte diversity increased with altitude. Unexpectedly, species richness was very high; 70 species of bryophytes were recorded including nine new records for the island. Diversity was also controlled by ecological microhabitats. Bryophyte species were structured into six categories according to altitude and microhabitat preferences. Results suggested that the high diversity of these cryptic organisms on this lava flow is fostered in part by their host substrate and their adaptative strategies on new substrates. On a broader scale, it was concluded that lava flows as primary mineral environments are important to conserve, as they support a high diversity of pioneer organisms that constitute the early stages of the development of La Réunion's remnant lowland rainforest.
Dynamics of fish in Australian desert springs: role of large‐mammal disturbance
Authors: Kodric‐Brown Astrid , Wilcox Chris , Bragg Jason G. , Brown James H. 
Published: February 2009

ABSTRACTHuman activities affect even the most remote and best preserved places on Earth. One of those places is Dalhousie Springs, Witjira National Park, in the arid centre of Australia. In 2003 we resurveyed the fish communities in springs to document changes since an earlier survey in 1991. Over the 12 years there were 18 population extirpations and only two colonizations, so total occurrences of five native species in 30 springs decreased from 83 to 67 populations. One species, the endemic Dalhousie goby, Chlamydogobius gloveri, accounted for 12 of the 18 population extirpations. Each fish species tended to persist in springs larger than some threshold size. Extirpations were related to spring size, with smaller springs more readily loosing populations, and to major habitat changes, which included large increases in the tropical reed Phragmites and concomitant decreases in open water, disturbed habitats, and dissolved oxygen. Extirpations of fish populations can be attributed primarily to habitat changes associated with reduced disturbance and herbivory as a result of the removal of feral livestock. These changes highlight the keystone impacts of large mammals on habitats and biotas of desert springs, and should be considered in management practices and policy decisions.
Inferring species decline from collection records: roller dung beetles in Italy (Coleoptera, Scarabaeidae)
Authors: Carpaneto Giuseppe Maria , Mazziotta Adriano , Valerio Laura 
Published: February 2009

ABSTRACTThe decline of roller dung beetles (Coleoptera, Scarabaeidae) in Italy, at national and regional level, was described using a database of both literature and unpublished data, since the late of 19th century. The probability of finding roller species was assessed for each decade of the 20th century in order to detect changes in their distribution and status. An analysis of decline was performed using a complementary approach of different extinction indexes, according to IUCN criteria. During the 20th century, both the absolute number of records and the UTM cells where roller beetles were found increased clearly as a consequence of the escalation of entomological surveys. Nevertheless, comparing R species (rollers) with all the scarab dung beetles from the first to the last quarter of the 20th century, the relative frequency of roller records decreased by 31%, while the relative number of occupied UTM cells dropped by 23%. Six roller species showed a significant decline in Italy from the first to the second part of the 20th century, and nine in the last 30years. Other two species disappeared from the majority of the northern regions. Finally, the values of all the extinction indexes were strongly correlated and detected a high risk of extinction in Italy for six species. A gradual change in land use during the last three decades, consisting of a reduced extension of grasslands in favour of either intensive agriculture or reforestation after abandonment of livestock raising, was likely the main factor inducing decline and local extinction of roller species.