Using non-systematically collected data to evaluate the conservation status of elusive species: a case study on Australia’s Oenpelli python

2020 ◽  
Vol 47 (2) ◽  
pp. 146
Author(s):  
Graeme R. Gillespie ◽  
Yusuke Fukuda ◽  
Peter McDonald
Keyword(s):  
Demographic Data ◽  
Conservation Status ◽  
Habitat Associations ◽  
Ecological Knowledge ◽  
Monitoring Methods ◽  
Snake Species ◽  
Environmental Models ◽  
Area Of Occupancy ◽  
Conservation Assessments ◽  
Monsoon Rainforest

Abstract ContextSpecies conservation assessments require information on distribution, habitat requirements and population demography and trends. Uncertain conservation assessments limit effective planning and may lead to poor management decisions. Top-order predators generally receive considerable attention from ecologists and conservation biologists, with the notable exception of large pythons and boas. They are typically elusive and have low population densities, posing challenges for ecological research and monitoring. Ecological and demographic data are lacking for most large snake species and are generally inadequate to properly assess conservation status or to evaluate their broader ecological roles. The Oenpelli python (Simalia oenpelliensis) is Australia’s second-longest snake species, but remains one of the least-known of the world’s pythons. AimsWe sought to use non-systematically collected data from multiple sources to evaluate Oenpelli python population trends and habitat associations, and to assess its conservation status. MethodsWe identified a priori biases in data and evaluated their influences on environmental models and temporal variability in reporting patterns. We then used these findings to assess the conservation status of this species, identify knowledge gaps, and refine future survey and monitoring methods. Key resultsOenpelli python records were strongly associated with monsoon rainforest, sandstone outcrops and perennial streams, irrespective of detection biases. Total area of occupancy was estimated to be 19252km2. Detection patterns were strongly seasonal and associated with periods of low rainfall and low moonlight, informing better-targeted survey and monitoring methods with improved sensitivity. ConclusionsOenpelli pythons have a highly fragmented distribution owing to their strong association with monsoon rainforest. This habitat is likely to provide more food resources and refuge from high temperatures than are the surrounding savanna woodlands. Detection probability should improve by surveying Oenpelli pythons in September on moonless nights and following periods of high rainfall. Taking a precautionary approach, the Oenpelli python qualifies as Vulnerable under IUCN criteria, supporting its current Red List and Northern Territory Government status. ImplicationsNon-systematically collected data on poorly known species can be used to improve conservation assessments where there may otherwise be high uncertainty. The present study also highlighted the paucity of ecological knowledge of large iconic snake species globally.

scholarly journals Habitat associations and conservation status of an endemic forest dwarf chameleon (Bradypodion sp.) from South Africa

Oryx ◽  
2006 ◽  
Vol 40 (2) ◽  
pp. 183-188 ◽  
Author(s):  
Walter J. Reisinger ◽  
Devi M. Stuart-Fox ◽  
Barend F.N. Erasmus
Keyword(s):  
South Africa ◽  
Conservation Status ◽  
Canopy Cover ◽  
Iucn Red List ◽  
Habitat Associations ◽  
Suitable Habitat ◽  
Area Of Occupancy ◽  
Forest Interior ◽  
Forest Remnants ◽  
Iucn Red List Criteria

We quantified habitat associations and evaluated the conservation status of a recently identified, undescribed species of dwarf chameleon, Bradypodion sp. nov. Dhlinza, endemic to scarp forest remnants in KwaZulu-Natal Province, South Africa. At the microhabitat scale the Dhlinza dwarf chameleon was found more often in forest gaps and near paths than highly disturbed edges or forest interior. Chameleon presence was not explained by forest physiognomic variables such as vine cover, shrub and tree density, or canopy cover. Presence near gaps may be better explained by the combined effects of the thermal microenvironment and food availability. The species is moderately common where it occurs, with estimated densities of 4.7, 8.7 and 29.7 individuals per ha within forest interior, edges and gaps respectively. At the landscape scale, the chameleon occurs only in three remnant forests: the Dhlinza, Entumeni and Ongoye Forests. The species' extent of occurrence was estimated to be 88 km2 and its area of occupancy 49 km2. Based on the small area of remaining suitable habitat, this species meets the requirements for categorization as Endangered according to IUCN Red List criteria.

scholarly journals Are conservation assessments of threatened species reliable? Updated distribution of the Endangered Sardinian newt Euproctus platycephalus and implications for Red List assessments of Italian amphibians

Oryx ◽  
2016 ◽  
Vol 51 (3) ◽  
pp. 482-488 ◽  
Author(s):  
Leonardo Vignoli ◽  
Daniele Macale ◽  
Luca Luiselli ◽  
Roberta Lecis ◽  
Paolo Casula
Keyword(s):  
Extinction Risk ◽  
Demographic Data ◽  
Conservation Status ◽  
Red List ◽  
Individual Species ◽  
Distribution Data ◽  
Sources Of Information ◽  
Amphibian Species ◽  
Island Endemic ◽  
Area Of Occupancy

AbstractAssessing and updating the extinction risk and conservation status of species and populations is paramount to guide management strategies. Maintaining up-to-date and realistic geographical distribution maps of individual species is one aspect of this. We report an updated distribution for an Italian island endemic amphibian, the Sardinian newt Euproctus platycephalus, categorized as Endangered on the IUCN global and national Red Lists. The distribution of E. platycephalus was reassessed by means of visual surveys, questionnaires, interviews and scientific literature. The species was found over a geographical range comparable to that used for the IUCN assessment but we recorded a significantly larger number of populations (57 vs 14). There was no appreciable difference in the species’ Extent of Occurrence between 1972–1974 and 2010–2015. Area of Occupancy increased between past (1972–1974 and 1999–2000) and present (2010–2015) distribution records. Based on this updated distribution and considering that several new populations have been found, the distribution of the species may still be underestimated. Given the novel distribution data provided here and the need for new long-term demographic data, we recommend that the conservation status of E. platycephalus be reassessed. In the Italian national Red List a potential overstatement of extinction risk is evident for other amphibian species, possibly because the information used in their assessment is deficient. Considering that monitoring rare and elusive species is costly and time consuming we recommend more extensive use of multiple sources of information for Red List assessments.

scholarly journals Mapping local and regional distribution of Lygophis paucidens Hoge, 1952 (Serpentes, Dipsadidae), an elusive snake from the sandy savannas of Brazil and Paraguay

Check List ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 75-81
Author(s):  
Filipe Alexandre Cabreirinha Serrano ◽  
João Paulo dos Santos Vieira-Alencar ◽  
Juan Camilo Diaz-Ricaurte ◽  
Cristiano de Campos Nogueira
Keyword(s):  
South America ◽  
Habitat Use ◽  
Conservation Status ◽  
Regional Distribution ◽  
Sandy Soils ◽  
Field Studies ◽  
Museum Specimens ◽  
Area Of Occupancy ◽  
Individual Point ◽  
Conservation Assessments

Lygophis paucidens Hoge, 1952 is a rare Neotropical snake, previously mapped using only a few individuals in five localities. Herein we update and discuss the distribution and conservation status of L. paucidens within major Neotropical ecoregions, providing previously unavailable data on distribution and habitat use. We compiled and mapped point locality records from literature and museum specimens, complemented by field studies in three localities. We used those records to map the species Extent of Occurrence (EOO) and Area of Occupancy (AOO), two range-related metrics of central relevance for conservation. We recovered 52 records from 46 vouchered specimens and six field records, distributed in 35 individual point localities, all within the diagonal of open vegetation in South America, with most records in cerrado savannas with sandy soils. Lygophis paucidens is likely a psammophilous species, which might explain its occurrence in savanna enclaves in forested ecoregions and its potentially discontinuous distribution. This knowledge is, therefore, useful in aiding future conservation assessments.

scholarly journals Assessment of the rarity and conservation status of the Colombian endemic brown hairy dwarf porcupine Coendou vestitus

Oryx ◽  
2020 ◽  
pp. 1-6
Author(s):  
María M. Torres-Martínez ◽  
Héctor E. Ramírez-Chaves ◽  
Elkin A. Noguera-Urbano ◽  
Fernando C. Passos
Keyword(s):  
Small Body ◽  
Conservation Status ◽  
Natural Habitat ◽  
Habitat Type ◽  
Iucn Red List ◽  
Red List ◽  
Small Range ◽  
Minimum Convex Polygon ◽  
Area Of Occupancy ◽  
Species Rarity

Abstract The brown hairy dwarf porcupine Coendou vestitus is a poorly studied Andean species endemic to Colombia. Its current Red List category is contradictory: globally it is categorized as Data Deficient but in Colombia it is categorized as Vulnerable. This contradiction has limited the implementation of conservation programmes. We evaluate the level of rarity of the species and provide consolidated information for a new assessment of its Red List status. We reviewed literature, photographs, and voucher specimens in natural history collections. Using the confirmed records, we estimated the extent of occurrence (EOO) based on the minimum convex polygon and the area of occupancy (AOO) summing the area of grid squares occupied by the species. We found that C. vestitus is very rare, with a small range, low estimated population density, occurrence in only one habitat type and small body size. The species has an EOO of 3,323 km2 and an AOO of 24 km2, based on six confirmed localities, all on the western slopes of the Eastern Cordillera, in the central Andean region of Colombia. Based on the species' rarity, restricted distribution, and threats to its natural habitat, we recommend its categorization as Endangered on the IUCN Red List. This will help delineate research and conservation efforts for this porcupine, which has a highly restricted range and inhabits the threatened Andean forest.

Local ecological knowledge to assist conservation status assessments in data poor contexts: a case study with the threatened sharks of the Brazilian Northeast

2021 ◽  
Author(s):  
Antoine O. H. C. Leduc ◽  
Fábio H. D. De Carvalho ◽  
Nigel E. Hussey ◽  
José Amorim Reis-Filho ◽  
Guilherme O. Longo ◽  
...  
Keyword(s):  
Local Ecological Knowledge ◽  
Conservation Status ◽  
Ecological Knowledge ◽  
Brazilian Northeast

scholarly journals An assessment of the distribution, population size and conservation status of the Santa Marta Foliage-gleaner Automolus rufipectus: a Sierra Nevada de Santa Marta endemic

2015 ◽  
Vol 25 (4) ◽  
pp. 451-465 ◽  
Author(s):  
ESTEBAN BOTERO-DELGADILLO ◽  
NICHOLAS BAYLY ◽  
CAMILA GÓMEZ ◽  
PAULO C. PULGARÍN-R. ◽  
CARLOS ANDRÉS PÁEZ
Keyword(s):  
Population Size ◽  
Sierra Nevada ◽  
Forest Cover ◽  
Conservation Status ◽  
Bird Species ◽  
Environmental Niche ◽  
Coffee Plantations ◽  
Habitat Transformation ◽  
Elevation Range ◽  
Area Of Occupancy

SummaryThe Santa Marta Foliage-gleaner Automolus rufipectus is one of 19 endemic bird species found in the Sierra Nevada de Santa Marta (SNSM) in northern Colombia but until recently it was considered a sub-species of the Ruddy Foliage-gleaner Automolus rubiginosus. Consequently, published information on its distribution and ecology is lacking, and while it is classified as near- threatened, this designation was based on limited quantitative data. To improve our knowledge of the Santa Marta Foliage-gleaner’s geographical distribution, elevation range, population density, habitat use and conservation status, we analysed both historical and recent site locality records and carried out variable distance transects within forested habitats and shade coffee plantations. We modelled the environmental niche of the species and subsequently estimated its extent of occurrence and area of occupancy, as well as population size. Our results consistently showed that the distribution of the Santa Marta Foliage-gleaner is more restricted than previously considered, both geographically and by elevation (we redefine elevation range as 600–1,875 m). This suggests that the species is more at risk of habitat transformation and combined with our estimates of population size (< 10,000 individuals), it is likely that the species will be uplisted to a higher threat category. More positively, and contrary to published accounts, we found that approximately 40% of the species’ range lies within protected areas. Nevertheless, we recommend the implementation of strategies to maintain forest cover on the western flank of the SNSM and further research to better define the species’ habitat needs and population dynamics.

scholarly journals Increasing accuracy: The advantage of using open access species occurrence database in the Red List assessment

2020 ◽  
Vol 21 (8) ◽  
Author(s):  
Iyan Robiansyah ◽  
Wita Wardani
Keyword(s):  
Open Access ◽  
Extinction Risk ◽  
Conservation Status ◽  
Iucn Red List ◽  
Red List ◽  
Suitable Habitat ◽  
Herbarium Specimens ◽  
Species Occurrence ◽  
Extent Of Occurrence ◽  
Area Of Occupancy

Abstract. Robiansyah I, Wardani W. 2020. Increasing accuracy: The advantage of using open access species occurrence database in the Red List assessment. Biodiversitas 21: 3658-3664. IUCN Red List is the most widely used instrument to assess and advise the extinction risk of a species. One of the criteria used in IUCN Red List is geographical range of the species assessed (criterion B) in the form of extent of occurrence (EOO) and/or area of occupancy (AOO). While this criterion is presumed to be the easiest to be completed as it is based mainly on species occurrence data, there are some assessments that failed to maximize freely available databases. Here, we reassessed the conservation status of Cibotium arachnoideum, a tree fern distributed in Sumatra and Borneo. This species was previously assessed by Praptosuwiryo (2020, Biodiversitas 21 (4): 1379-1384) which classified the species as Endangered (EN) under criteria B2ab(i,ii,iii); C2a(ii). Using additional data from herbarium specimens recorded in the Global Biodiversity Information Facility (GBIF) website and from peer-reviewed scientific papers, in the present paper we show that C. arachnoideum has a larger extent of occurrence (EOO) and area of occupancy (AOO), more locations and different conservation status compared to those in Praptosuwiryo (2020). Our results are supported by the predicted suitable habitat map of C. arachnoideum produced by MaxEnt modelling method. Based on our assessment, we propose the category of Vulnerable (VU) C2a(i) as the global conservation status for C. arachnoideum. Our study implies the advantage of using open access databases to increase the accuracy of extinction risk assessment under the IUCN Red List criteria in regions like Indonesia, where adequate taxonomical information is not always readily available.

scholarly journals Regional Assessment of the Conservation Status of Snubfin Dolphins (Orcaella heinsohni) in the Kimberley Region, Western Australia

2021 ◽  
Vol 7 ◽  
Author(s):  
Phil J. Bouchet ◽  
Deborah Thiele ◽  
Sarah A. Marley ◽  
Kelly Waples ◽  
Frank Weisenberger ◽  
...  
Keyword(s):  
Western Australia ◽  
Conservation Status ◽  
Regional Scale ◽  
Indigenous Communities ◽  
Multiple Sources ◽  
Marine Animals ◽  
Cetacean Species ◽  
Detection Rates ◽  
Area Of Occupancy ◽  
Kernel Approach

Implementing conservation measures for data-limited species is a fundamental challenge for wildlife managers and policy-makers, and proves difficult for cryptic marine animals occurring in naturally low numbers across remote seascapes. There is currently scant information on the abundance and habitat preferences of Australian snubfin dolphins (Orcaella heinsohni) throughout much of their geographical range, and especially within the Kimberley region of northern Western Australia. Such knowledge gaps curtail rigorous threat assessments on both local and regional scales. To address this and assist future conservation listings, we built the first comprehensive catalog of snubfin dolphin sightings for the Kimberley. We used these data to estimate the species’ extent of occurrence (EOO) and area of occupancy (AOO) along the region’s 7,000 km coastline, following a simple Bootstrap bivariate kernel approach to combine datasets of varying quality and quantify uncertainty. Our catalog consists of 1,597 visual detections of snubfin dolphins made over a period of 17 years (2004–2020) and collated from multiple sources, including online biodiversity repositories, peer-reviewed scientific articles, citizen science programs, as well as dedicated marine wildlife surveys with local Indigenous communities and Ranger groups. Snubfin dolphins were consistently encountered in shallow waters (&lt;21 m depth) close to (&lt;15 km) freshwater inputs, with high detection rates in known hotspots (e.g., Roebuck Bay, Cygnet Bay) as well as in coastal habitats suspected to be suitable (e.g., Prince Regent River and surrounds, King Sound, Doubtful Bay, Napier Broome Bay and the upper Cambridge Gulf). Bootstrap estimates of EOO and AOO were 38,300 (95% CI: 25,451–42,437) km2 and 700 (656–736) km2 respectively, suggesting that snubfin dolphins in the Kimberley are likely Vulnerable under IUCN criteria B2 at a regional scale, in keeping with their global classification. Our study offers insights into the distribution of a vulnerable coastal cetacean species and demonstrates the value of integrating multiple data sources for informing conservation assessments in the face of uncertainty.

scholarly journals Distribution, habitat associations, and conservation status updates for the pilose crayfish Pacifastacus gambelii (Girard, 1852) and Snake River pilose crayfish Pacifastacus connectens (Faxon, 1914) of the western United States

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5668 ◽  
Author(s):  
Rachel M. Egly ◽  
Eric R. Larson
Keyword(s):  
United States ◽  
Classification Tree ◽  
Conservation Status ◽  
False Positives ◽  
Habitat Associations ◽  
Boosted Regression Trees ◽  
Western United States ◽  
Snake River ◽  
Precipitation Seasonality ◽  
Historical Sites

Our study evaluates the distribution, habitat associations, and current conservation status of the Snake River pilose crayfish Pacifastacus connectens (Faxon, 1914) and pilose crayfish Pacifastacus gambelii (Girard, 1852), two little-studied and data-deficient species endemic to the western United States. We first developed a species distribution model (SDM) for the pilose crayfishes based on their historical occurrence records using boosted regression trees and freshwater GIS data layers. We then sampled 163 sites in the summers of 2016 and 2017 within the distribution of these crayfishes, including 50 where these species were observed historically. We next compared our field results to modeled predictions of suitable habitat from the SDM. Our SDM predicted 73 sites (45%) we sampled as suitable for the pilose crayfishes, with a moderate AUC value of 0.824. The pilose crayfishes were generally predicted to occur in larger streams and rivers with less extreme upstream temperature and precipitation seasonality. We found the pilose crayfishes at only 20 (12%) of the 163 total sites we sampled, 14 (20%) of the 73 sites predicted as suitable for them by our SDM, and 12 (24%) of 50 historical sites that we sampled. We found the invasive virile crayfish Faxonius virilis (Hagen, 1870) at 22 sites total and 12 (24%) historical sites for the pilose crayfishes, and we found the “native invader” signal crayfish Pacifastacus leniusculus (Dana, 1852) at 29 sites total and 6 (12%) historical sites for the pilose crayfishes. We subsequently used a single classification tree to identify factors associated with our high rate of false positives for contemporary pilose crayfish distributions relative to our SDM. This classification tree identified the presence of invasive crayfishes, impairment of the benthic community, and sampling method as some of the factors differentiating false positives relative to true positives for the pilose crayfishes. Our study identified the historical distribution and habitat associations for P. connectens and P. gambelii using an SDM and contrasted this prediction to results of contemporary field sampling. We found that the pilose crayfishes have seemingly experienced substantial range declines, attributable to apparent displacement by invasive crayfishes and impairment or change to stream communities and habitat. We recommend increased conservation and management attention to P. connectens and P. gambelii in response to these findings.

scholarly journals Overview on the distribution of gorgonian species in Tunisian marine coastal waters (central Mediterranean)

2018 ◽  
Vol 82 (1) ◽  
pp. 55 ◽  
Author(s):  
Raouia Ghanem ◽  
Emna Soufi Kechaou ◽  
Jamila Ben Souissi ◽  
Joaquim Garrabou
Keyword(s):  
Coastal Waters ◽  
Local Ecological Knowledge ◽  
Conservation Status ◽  
Ecological Knowledge ◽  
Central Mediterranean ◽  
Management Actions ◽  
Conservation Actions ◽  
Gorgonian Species ◽  
Species Richness And Abundance ◽  
And Function

Gorgonian species play an important ecological role in the structure and function of marine communities. Human activities are negatively affecting the conservation status of gorgonian populations in the Mediterranean. Acquiring knowledge of gorgonian distribution is therefore a key step required to promote efficient management and conservation actions. However, information on the distribution of gorgonian species is lacking in many Mediterranean areas. This study aimed to provide an overview of the geographic and bathymetric distributions of gorgonians in the coastal waters of the Tunisian coast (1136 km). The sampling design encompassed three sectors, 27 localities and 87 sites. Information was collected from scuba diving (26 sites) and local ecological knowledge surveys of fishermen and divers (132 interviews), as well as from a literature review. Overall, the occurrence of eight gorgonians was confirmed at 54 out of the 87 sites surveyed in Tunisian coastal waters (7-120 m depth). The species that were found were Eunicella singularis, Eunicella cavolini, Paramuricea clavata, Paramuricea macrospina, Leptogorgia sarmentosa, Eunicella verrucosa, Corallium rubrum and Ellisella paraplexauroides. The highest gorgonian species richness and abundance was recorded in northern, followed by eastern Tunisian waters. In the southern areas only one species was recorded. This pattern was related to the rocky substrate that characterizes the northern and eastern coasts of Tunisia. This study is the first to report the occurrence of E. singularis, E. cavolini, E. verrucosa and Leptogorgia sarmentosa in northern and eastern Tunisian waters. The results are discussed in the hope of guiding future conservation and management actions for gorgonian assemblages in Tunisia.

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