Survival probability of a population of Madagascar spider tortoises (Pyxis arachnoides)

2012 ◽  
Vol 33 (1) ◽  
pp. 141-144 ◽  
Author(s):  
Ryan Walker ◽  
Luca Luiselli ◽  
Tsilavo Rafeliarisoa

The spider tortoise (Pyxis arachnoides) is endemic to the coastal, dry forests of southwest Madagascar, one of the country’s most threatened habitats. Very little is known of the biology of this Critically Endangered species. We devised a three year capture-mark-recapture study to assess mean annual survival for the following cohorts; juvenile, adult male, adult female and adult of both sexes, for a population of spider tortoises using a Cormack-Jolly-Seber model. Low recapture probabilities prevented the modelling of all but the adult of both sexes cohort. Mean annual survival was 0.823 (; ). We hypothesise that habitat loss could be impacting the survival of this cohort; however establishing control data to test for this is difficult because of the widespread habitat loss, even within protected areas. Therefore we suggest extending the study across a number of gradients of impacted habitat and increase the duration of the study to assess this risk to the population and improve model robustness.

2002 ◽  
Vol 8 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Giacomo Tavecchia ◽  
Roger Pradel ◽  
François Gossmann ◽  
Claudine Bastat ◽  
Yves Ferrand ◽  
...  

2020 ◽  
Vol 12 (11) ◽  
pp. 16502-16509
Author(s):  
Sandeep Das ◽  
K.P. Rajkumar ◽  
K.A. Sreejith ◽  
M. Royaltata ◽  
P.S. Easa

Abstract: The Resplendent Shrub Frog, Raorchestes resplendens Biju, Shouche, Dubois, Dutta, & Bossuyt, 2010 is a Critically Endangered species endemic to the Western Ghats and was considered to be restricted to a three-square kilometer patch atop Anamudi summit.  In this study, we report 36 new locations of the species from the Anamalai massif of the southern Western Ghats.  Niche-based prediction modelling suggests that the species is restricted to Anamalai massif.  The call description of this frog is also provided for the first time. The preferred microhabitat of the frog is Chrysopogon grass clumps in the marshy/swampy montane grassland ecosystem. Restricted to a small area with controlled burning management practiced in its habitat, R. resplendens needs immediate attention.


Author(s):  
Akshay Tanna ◽  
Daniel Fernando ◽  
Ramajeyam Gobiraj ◽  
Buddhi M. Pathirana ◽  
Sahan Thilakaratna ◽  
...  

2021 ◽  
Vol 9 (2) ◽  
pp. 220
Author(s):  
Michele Bertoni Mann ◽  
Janira Prichula ◽  
Ícaro Maia Santos de Castro ◽  
Juliana Mello Severo ◽  
Michelle Abadie ◽  
...  

Melanophryniscus admirabilis (admirable red-belly toad) is a microendemic and critically endangered species found exclusively along 700 m of the Forqueta River, in a fragment of the Atlantic Forest of southern Brazil. One of the greatest concerns regarding the conservation of this species is the extensive use of pesticides in areas surrounding their natural habitat. In recent years, the adaptation and persistence of animal species in human-impacted environments have been associated with microbiota. Therefore, the present study aimed to characterize the oral bacterial community of wild M. admirabilis and to address the question of how this community might contribute to this toad’s adaptation in the anthropogenic environment as well as its general metabolic capabilities. A total of 11 oral samples collected from wild M. admirabilis were characterized and analyzed via high-throughput sequencing. Fragments of the 16S rRNA variable region 4 (V4) were amplified, and sequencing was conducted using an Ion Personal Genome Machine (PGM) System with 316 chips. A total of 181,350 sequences were obtained, resulting in 16 phyla, 34 classes, 39 orders, and 77 families. Proteobacteria dominated (53%) the oral microbiota of toads, followed by Firmicutes (18%), Bacteroidetes (17%), and Actinobacteria (5%). No significant differences in microbial community profile from among the samples were reported, which suggests that the low dietary diversity observed in this population may directly influence the bacterial composition. Inferences of microbiome function were performed using PICRUSt2 software. Important pathways (e.g., xenobiotic degradation pathways for pesticides and aromatic phenolic compounds) were detected, which suggests that the bacterial communities may serve important roles in M. admirabilis health and survival in the anthropogenic environment. Overall, our results have important implications for the conservation and management of this microendemic and critically endangered species.


2015 ◽  
Vol 65 (3-4) ◽  
pp. 209-217 ◽  
Author(s):  
Yadong Xue ◽  
Diqiang Li ◽  
Wenfa Xiao ◽  
Fang Liu ◽  
Yuguang Zhang ◽  
...  

There are significant gaps in our knowledge of wild camel ecology; especially the activity patterns that allow them to adapt to desert environments. The wild Bactrian camel (Camelus bactrianus) is a critically endangered species that survives in the extreme desert conditions of Central Asia. We conducted camera trapping surveys at seven watering sites in the northern piedmont of the Altun Mountains from 2010 to 2012. We analyzed the frequency of photo-captures to elucidate the wild camels’ diel activity patterns, and the seasonal variation in their activity at watering sites. We found that these wild camels were predominantly diurnal at watering sites, with an increase in relative activity from sunrise, reaching a peak toward midday, and then gradually decreasing in activity until sunset. The camels visited watering sites more often in winter than in summer. These results provide a guide for water development in the conservation of ungulates in arid areas.


2010 ◽  
Vol 151 (3) ◽  
pp. 627-636 ◽  
Author(s):  
David Monticelli ◽  
Ricardo Ceia ◽  
Ruben Heleno ◽  
Hugo Laborda ◽  
Sergio Timóteo ◽  
...  

PLoS ONE ◽  
2015 ◽  
Vol 10 (9) ◽  
pp. e0139231 ◽  
Author(s):  
Guohua Ding ◽  
Chunye Li ◽  
Xu Han ◽  
Chunyu Chi ◽  
Dawei Zhang ◽  
...  

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