scholarly journals Predicting distributions of rare species: the case of the false coral snake Rhinobothryum bovallii (Serpentes: Colubridae)

2020 ◽  
Vol 19 (2) ◽  
pp. 141-164
Author(s):  
Fabio Leonardo Meza-Joya ◽  
Julián Andrés Rojas-Morales ◽  
Eliana Ramos
Keyword(s):  
Rare Species ◽  
Natural Habitat ◽  
Positive Association ◽  
Disjunct Distribution ◽  
Conservation Strategies ◽  
Suitable Habitat ◽  
Coral Snake ◽  
Distribution Models ◽  
Core Habitat ◽  
Precipitation Seasonality

Predicting distributions of rare species: the case of the false coral snake Rhinobothryum bovallii (Serpentes: Colubridae). Typically, the lack of enough high-quality occurrence data makes it diffcult to defne the geographic distribution of rare species. However, species distribution models provide a powerful tool for biodiversity management, including efforts to predict the distributions of rare species. Herein, new and historical data are used to model the distribution of the False Tree Coral snake, Rhinobothryum bovallii. The prediction map reveals a disjunct distribution for this species, from the Central American Isthmus to the northwestern portion of South America, with the species occupying lowlands and premontane forests below about 1500 m elevation. We identifed 491,516 km2 of suitable habitat for R. bovallii (minimum training presence threshold of 0.424) and 59,353 km2 of core habitat, with concentrations in three relatively isolated core areas (10-percentile training presence threshold of 0.396), as follow: (1) a “northern core” along the Pacifc and Caribbean coasts of Panama; (2) a “central core” in the Middle Magdalena Valley in Colombia; and (3) a “southern core” in the Ecuadorian Chocó. The occurrence of this species has a strong positive association with low precipitation seasonality, high precipitation in the warmest quarter, and low variability in annual temperature. Xeric and semiarid areas are unsuitable for this species and may pose environmental barriers limiting its distributional range. These results may lead to the discovery of additional populations of R. bovallii, identify priority survey areas, and by determining the extent of its natural habitat promote effective conservation strategies.

scholarly journals Potential Distribution of the Biocontrol Agent Toxorhynchites rutilus By 2070

2020 ◽  
Vol 36 (3) ◽  
pp. 131-138
Author(s):  
Daniel S. Marshall ◽  
Christopher J. Butler
Keyword(s):  
Climate Change ◽  
Biocontrol Agent ◽  
Mosquito Control ◽  
Disease Incidence ◽  
Suitable Habitat ◽  
Climate Change Scenarios ◽  
Distribution Models ◽  
Precipitation Seasonality ◽  
Bioclimatic Variables ◽  
Toxorhynchites Rutilus

ABSTRACT Climate change projections indicate that mosquito distributions will expand to include new areas of North America, increasing human exposure to mosquito-borne disease. Controlling these vectors is imperative, as mosquito-borne disease incidence will rise in response to expansion of mosquito range and increased seasonality. One means of mosquito control used in the USA is the biocontrol agent, Toxorhynchites rutilus. Climate change will open new habitats for its use by vector control organizations, but the extent of this change in habitat is currently unknown. We used a maximum entropy approach to create species distribution models for Tx. rutilus under 4 climate change scenarios by 2070. Mean temperature of warmest quarter (22.6°C to 29.1°C), annual precipitation (1,025.15 mm to 1,529.40 mm), and precipitation seasonality (≤17.86) are the most important bioclimatic variables for suitable habitat. The center of current possible habitat distribution of Tx. rutilus is in central Tennessee. Depending upon the scenario, we expect centroids to shift north-northeast by 97.68 km to 280.16 km by 2070. The extreme change in area of greater than 50% suitable habitat probability is 141.14% with 99.44% area retained. Our models indicate limited change in current habitat as well as creation of new habitat. These results are promising for North American mosquito control programs for the continued and potential combat of vector mosquitoes using Tx. rutilus.

scholarly journals Quantifying range decline and remaining populations of the large marsupial carnivore of Australia’s tropical rainforest

2020 ◽  
Vol 101 (4) ◽  
pp. 1021-1034
Author(s):  
Adriana Uzqueda ◽  
Scott Burnett ◽  
Lorenzo V Bertola ◽  
Conrad J Hoskin
Keyword(s):  
Suitable Habitat ◽  
Population Declines ◽  
Large Area ◽  
Distribution Models ◽  
Road Density ◽  
Core Habitat ◽  
Annual Range ◽  
Time Periods ◽  
Peripheral Areas ◽  
High Precipitation

Abstract Large predators are particularly susceptible to population declines due to large area requirements, low population density, and conflict with humans. Their low density and secretive habits also make it difficult to know the spatial extent, size, and connectivity of populations; declines hence can go unnoticed. Here, we quantified decline in a large marsupial carnivore, the spotted-tailed quoll (Dasyurus maculatus gracilis), endemic to the Wet Tropics rainforest of northeast Australia. We compiled a large database of occurrence records and used species distributional modeling to estimate the distribution in four time periods (Pre-1956, 1956–1975, 1976–1995, 1996–2016) using climate layers and three human-use variables. The most supported variables in the distribution models were climatic, with highly suitable quoll habitat having relatively high precipitation, low temperatures, and a narrow annual range in temperature. Land-use type and road density also influenced quoll distribution in some time periods. The modeling revealed a significant decline in the distribution of D. m. gracilis over the last century, with contraction away from peripheral areas and from large areas of the Atherton Tablelands in the center of the distribution. Tests of the change in patch availability for populations of 20, 50, and 100 individuals revealed a substantial (17–32%) decline in available habitat for all population sizes, with a particular decline (31–40%) in core habitat (i.e., excluding edges). Six remaining populations were defined. Extrapolating capture–recapture density estimates derived from two populations in 2017 suggests these populations are small and range from about 10 to 160 individuals. Our total population estimate sums to 424 individuals, but we outline why this estimate is positively skewed and that the actual population size may be < 300 individuals. Continued decline and apparent absence in areas of highly suitable habitat suggests some threats are not being captured in our models. From our results, we provide management and research recommendations for this enigmatic predator.

CONSERVATION OF RARE SPECIES PLANTS AND LICHENS IN SITU WITH PLANNED ANTHROPOGENIC ACTIVITIES: BASIC APPROACHES AND IMPLEMENTATION PRINCIPLES

2018 ◽  
Vol 12 (7-8) ◽  
pp. 38-45
Author(s):  
A. N. EFREMOV ◽  
N. V. PLIKINA ◽  
T. ABELI
Keyword(s):  
Rare Species ◽  
Technology Implementation ◽  
Technology Development ◽  
Anthropogenic Activities ◽  
Natural Habitat ◽  
Local Population ◽  
Main Stage ◽  
Social Risks

Rare species are most vulnerable to man-made impacts, due to their biological characteristics or natural resource management. As a rule, the economic impact is associated with the destruction and damage of individual organisms, the destruction or alienation of habitats. Unfortunately, the conservation of habitat integrity is an important protection strategy, which is not always achievable in the implementation of industrial and infrastructural projects. The aim of the publication is to summarize the experience in the field of protection of rare species in the natural habitat (in situ), to evaluate and analyze the possibility of using existing methods in design and survey activities. In this regard, the main methodological approaches to the protection of rare species in the natural habitat (in situ) during the proposed economic activity were reflected. The algorithm suggested by the authors for implementing the in situ project should include a preparatory stage (initial data collection, preliminary risk assessments, technology development, obtaining permitting documentation), the main stage, the content of which is determined by the selected technology and a long monitoring stage, which makes it possible to assess the effectiveness of the taken measures. Among the main risks of in situ technology implementation, the following can be noted: the limited resources of the population that do not allow for the implementation of the procedure without prior reproduction of individuals in situ (in vitro); limited knowledge of the biology of the species; the possibility of invasion; the possibility of crossing for closely related species that сo-exist in the same habitat; social risks and consequences, target species or population may be important for the local population; financial risks during the recovery of the population. The available experience makes it possible to consider the approach to the conservation of rare species in situ as the best available technology that contributes to reducing negative environmental risks.

Geospatial information informs bonobo conservation efforts

2018 ◽  
Author(s):  
Janet Nackoney ◽  
Jena Hickey ◽  
David Williams ◽  
Charly Facheux ◽  
Takeshi Furuichi ◽  
...  
Keyword(s):  
Spatial Data ◽  
Pan Paniscus ◽  
Democratic Republic Of Congo ◽  
Conservation Strategies ◽  
Suitable Habitat ◽  
Community Based ◽  
Geospatial Information ◽  
République Démocratique Du Congo ◽  
Nous Montrons ◽  
Dynamic Conservation

The endangered bonobo (Pan paniscus), endemic to the Democratic Republic of Congo (DRC), is threatened by hunting and habitat loss. Two recent wars and ongoing conflicts in the DRC greatly challenge conservation efforts. This chapter demonstrates how spatial data and maps are used for monitoring threats and prioritizing locations to safeguard bonobo habitat, including identifying areas of highest conservation value to bonobos and collaboratively mapping community-based natural resource management (CBNRM) zones for reducing deforestation in key corridor areas. We also highlight the development of a range-wide model that analysed a variety of biotic and abiotic variables in conjunction with bonobo nest data to map suitable habitat. Approximately 28 per cent of the range was predicted suitable; of that, about 27.5 per cent was located in official protected areas. These examples highlight the importance of employing spatial data and models to support the development of dynamic conservation strategies that will help strengthen bonobo protection. Le bonobo en voie de disparition (Pan paniscus), endémique à la République Démocratique du Congo (DRC), est menacé par la chasse et la perte de l’habitat. Deux guerres récentes et les conflits en cours dans le DRC menacent les efforts de conservation. Ici, nous montrons comment les données spatiales et les cartes sont utilisées pour surveiller les menaces et prioriser les espaces pour protéger l’habitat bonobo, inclut identifier les zones de plus haute valeur de conservation aux bonobos. En plus, la déforestation est réduite par une cartographie collaborative communale de gestion de ressources dans les zones de couloirs essentiels. Nous soulignons le développement d’un modèle de toute la gamme qui a analysé un variété de variables biotiques et abiotiques en conjonction avec les données de nid bonobo pour tracer la carte d’un habitat adéquat. Environ 28 per cent de la gamme est prédit adéquat; de cela, environ 27.5 per cent est dans une zone officiellement protégée. Ces exemples soulignent l’importance d’utiliser les données spatiales et les modèles pour soutenir le développement de stratégies de conservations dynamiques qui aideront à renforcer la protection des bonobos.

Mapping Arctic clam abundance using multiple datasets, models, and a spatially explicit accuracy assessment

2019 ◽  
Vol 76 (7) ◽  
pp. 2349-2361
Author(s):  
Benjamin Misiuk ◽  
Trevor Bell ◽  
Alec Aitken ◽  
Craig J Brown ◽  
Evan N Edinger
Keyword(s):  
Spatial Autocorrelation ◽  
Cross Validation ◽  
Predictive Accuracy ◽  
Accuracy Assessment ◽  
Small Scale ◽  
Suitable Habitat ◽  
Distribution Models ◽  
Management Tools ◽  
Seabed Topography ◽  
Leave One Out

Abstract Species distribution models are commonly used in the marine environment as management tools. The high cost of collecting marine data for modelling makes them finite, especially in remote locations. Underwater image datasets from multiple surveys were leveraged to model the presence–absence and abundance of Arctic soft-shell clam (Mya spp.) to support the management of a local small-scale fishery in Qikiqtarjuaq, Nunavut, Canada. These models were combined to predict Mya abundance, conditional on presence throughout the study area. Results suggested that water depth was the primary environmental factor limiting Mya habitat suitability, yet seabed topography and substrate characteristics influence their abundance within suitable habitat. Ten-fold cross-validation and spatial leave-one-out cross-validation (LOO CV) were used to assess the accuracy of combined predictions and to test whether this was inflated by the spatial autocorrelation of transect sample data. Results demonstrated that four different measures of predictive accuracy were substantially inflated due to spatial autocorrelation, and the spatial LOO CV results were therefore adopted as the best estimates of performance.

scholarly journals Scaling up ideals to freedom: are densities of red knots across western Europe consistent with ideal free distribution?

2011 ◽  
Vol 278 (1719) ◽  
pp. 2728-2736 ◽  
Author(s):  
Gwenaël Quaintenne ◽  
Jan A. van Gils ◽  
Pierrick Bocher ◽  
Anne Dekinga ◽  
Theunis Piersma
Keyword(s):  
Uniform Distribution ◽  
Western Europe ◽  
Ideal Free Distribution ◽  
Scale Up ◽  
Suitable Habitat ◽  
Distribution Models ◽  
Free Distribution ◽  
Wintering Areas ◽  
Wintering Area ◽  
Suitable Habitats

Local studies have shown that the distribution of red knots Calidris canutus across intertidal mudflats is consistent with the predictions of an ideal distribution, but not a free distribution. Here, we scale up the study of feeding distributions to their entire wintering area in western Europe. Densities of red knots were compared among seven wintering sites in The Netherlands, UK and France, where the available mollusc food stocks were also measured and from where diets were known. We tested between three different distribution models that respectively assumed (i) a uniform distribution of red knots over all areas, (ii) a uniform distribution across all suitable habitat (based on threshold densities of harvestable mollusc prey), and (iii) an ideal and free distribution (IFD) across all suitable habitats. Red knots were not homogeneously distributed across the different European wintering areas, also not when considering suitable habitats only. Their distribution was best explained by the IFD model, suggesting that the birds are exposed to interference and have good knowledge about their resource landscape at the spatial scale of NW Europe, and that the costs of movement between estuaries, at least when averaged over a whole winter, are negligible.

scholarly journals An updated understanding of Texas bumble bee (Hymenoptera: Apidae) species presence and potential distributions in Texas, USA

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3612 ◽  
Author(s):  
Jessica L. Beckham ◽  
Samuel Atkinson
Keyword(s):  
Citizen Science ◽  
Species Distributions ◽  
Field Studies ◽  
The United States ◽  
Bumble Bee ◽  
Suitable Habitat ◽  
Distribution Models ◽  
Species List ◽  
Central Texas ◽  
Declining Species

Texas is the second largest state in the United States of America, and the largest state in the contiguous USA at nearly 700,000 sq. km. Several Texas bumble bee species have shown evidence of declines in portions of their continental ranges, and conservation initiatives targeting these species will be most effective if species distributions are well established. To date, statewide bumble bee distributions for Texas have been inferred primarily from specimen records housed in natural history collections. To improve upon these maps, and help inform conservation decisions, this research aimed to (1) update existing Texas bumble bee presence databases to include recent (2007–2016) data from citizen science repositories and targeted field studies, (2) model statewide species distributions of the most common bumble bee species in Texas using MaxEnt, and (3) identify conservation target areas for the state that are most likely to contain habitat suitable for multiple declining species. The resulting Texas bumble bee database is comprised of 3,580 records, to include previously compiled museum records dating from 1897, recent field survey data, and vetted records from citizen science repositories. These data yielded an updated state species list that includes 11 species, as well as species distribution models (SDMs) for the most common Texas bumble bee species, including two that have shown evidence of range-wide declines: B. fraternus (Smith, 1854) and B. pensylvanicus (DeGeer, 1773). Based on analyses of these models, we have identified conservation priority areas within the Texas Cross Timbers, Texas Blackland Prairies, and East Central Texas Plains ecoregions where suitable habitat for both B. fraternus and B. pensylvanicus are highly likely to co-occur.

scholarly journals Evaluating ecological uniqueness over broad spatial extents using species distribution modelling

2021 ◽  
Author(s):  
Gabriel Dansereau ◽  
Pierre Legendre ◽  
Timothée Poisot
Keyword(s):  
North America ◽  
Species Distribution ◽  
Rare Species ◽  
Beta Diversity ◽  
Species Distribution Modelling ◽  
Distribution Models ◽  
Science Data ◽  
Distribution Modelling ◽  
Ecological Uniqueness ◽  
The Relationship

Aim: Local contributions to beta diversity (LCBD) can be used to identify sites with high ecological uniqueness and exceptional species composition within a region of interest. Yet, these indices are typically used on local or regional scales with relatively few sites, as they require information on complete community compositions difficult to acquire on larger scales. Here, we investigate how LCBD indices can be used to predict ecological uniqueness over broad spatial extents using species distribution modelling and citizen science data. Location: North America. Time period: 2000s. Major taxa studied: Parulidae. Methods: We used Bayesian additive regression trees (BARTs) to predict warbler species distributions in North America based on observations recorded in the eBird database. We then calculated LCBD indices for observed and predicted data and examined the site-wise difference using direct comparison, a spatial autocorrelation test, and generalized linear regression. We also investigated the relationship between LCBD values and species richness in different regions and at various spatial extents and the effect of the proportion of rare species on the relationship. Results: Our results showed that the relationship between richness and LCBD values varies according to the region and the spatial extent at which it is applied. It is also affected by the proportion of rare species in the community. Species distribution models provided highly correlated estimates with observed data, although spatially autocorrelated. Main conclusions: Sites identified as unique over broad spatial extents may vary according to the regional richness, total extent size, and the proportion of rare species. Species distribution modelling can be used to predict ecological uniqueness over broad spatial extents, which could help identify beta diversity hotspots and important targets for conservation purposes in unsampled locations.

scholarly journals The modeled distribution of corals and sponges surrounding the Salas y Gómez and Nazca ridges with implications for high seas conservation

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11972
Author(s):  
Samuel Georgian ◽  
Lance Morgan ◽  
Daniel Wagner
Keyword(s):  
Suitable Habitat ◽  
Distribution Models ◽  
Seafloor Topography ◽  
Saturation State ◽  
Direct Observations ◽  
Rich Diversity ◽  
Spatial Management ◽  
Phosphate Silicate ◽  
Glass Sponges ◽  
Suitable Habitats

The Salas y Gómez and Nazca ridges are two adjacent seamount chains off the west coast of South America that collectively contain more than 110 seamounts. The ridges support an exceptionally rich diversity of benthic and pelagic communities, with the highest level of endemism found in any marine environment. Despite some historical fishing in the region, the seamounts are relatively pristine and represent an excellent conservation opportunity to protect a global biodiversity hotspot before it is degraded. One obstacle to effective spatial management of the ridges is the scarcity of direct observations in deeper waters throughout the region and an accompanying understanding of the distribution of key taxa. Species distribution models are increasingly used tools to quantify the distributions of species in data-poor environments. Here, we focused on modeling the distribution of demosponges, glass sponges, and stony corals, three foundation taxa that support large assemblages of associated fauna through the creation of complex habitat structures. Models were constructed at a 1 km2 resolution using presence and pseudoabsence data, dissolved oxygen, nitrate, phosphate, silicate, aragonite saturation state, and several measures of seafloor topography. Highly suitable habitat for each taxa was predicted to occur throughout the Salas y Gómez and Nazca ridges, with the most suitable habitat occurring in small patches on large terrain features such as seamounts, guyots, ridges, and escarpments. Determining the spatial distribution of these three taxa is a critical first step towards supporting the improved spatial management of the region. While the total area of highly suitable habitat was small, our results showed that nearly all of the seamounts in this region provide suitable habitats for deep-water corals and sponges and should therefore be protected from exploitation using the best available conservation measures.

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