Detection of critically endangered marine species with dwindling populations in the wild using eDNA gives hope for sawfishes

AbstractThe gharial (Gavialis gangeticus) is a critically endangered crocodylian, endemic to the Indian subcontinent. The species has experienced severe population decline during the twentieth century owing to habitat loss, poaching, and mortalities in passive fishing. Its extant populations have largely recovered through translocation programmes initiated in 1975. Understanding the genetic status of these populations is crucial for evaluating the effectiveness of the ongoing conservation efforts. This study assessed the genetic diversity, population structure, and evidence of genetic bottlenecks of the two managed populations inhabiting the Chambal and Girwa Rivers, which hold nearly 80% of the global gharial populations. We used seven polymorphic nuclear microsatellite loci and a 520 bp partial fragment of the mitochondrial control region (CR). The overall mean allelic richness (Ar) was 2.80 ± 0.40, and the observed (Ho) and expected (He) heterozygosities were 0.40 ± 0.05 and 0.39 ± 0.05, respectively. We observed low levels of genetic differentiation between populations (FST = 0.039, P < 0.05; G’ST = 0.058, P < 0.05 Jost’s D = 0.016, P < 0.05). The bottleneck analysis using the M ratio (Chambal = 0.31 ± 0.06; Girwa = 0.41 ± 0.12) suggested the presence of a genetic bottleneck in both populations. The mitochondrial CR also showed a low level of variation, with two haplotypes observed in the Girwa population. This study highlights the low level of genetic diversity in the two largest managed gharial populations in the wild. Hence, it is recommended to assess the genetic status of extant wild and captive gharial populations for planning future translocation programmes to ensure long-term survival in the wild.

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Monitoring invasive mammalian predator populations sharing habitat with the Critically Endangered Puerto Rican parrot Amazona vittata

Oryx ◽

10.1017/s0030605305001286 ◽

2005 ◽

Vol 40 (1) ◽

pp. 95-102 ◽

Cited By ~ 12

Author(s):

Richard Engeman ◽

Desley Whisson ◽

Jessica Quinn ◽

Felipe Cano ◽

Pedro Quiñones ◽

...

Keyword(s):

Puerto Rican ◽

Habitat Type ◽

Critically Endangered ◽

Mammal Species ◽

Forest Sites ◽

The World ◽

Mammalian Predators ◽

In The Wild ◽

Amazona Vittata ◽

Black Rats

Critically Endangered Puerto Rican parrots Amazona vittata are one of the rarest birds in the world. Several exotic mammal species capable of preying on Puerto Rican parrots cohabit the Caribbean National Forest with the only wild population of these parrots. We used tracking plates, monitoring blocks and trapping to index black rats, small Indian mongooses and feral cats in parrot habitat and in public-use areas in the same habitat type. We had high trap success for black rats at all sites (42% of all sites combined), among the highest reported in the world. Rat response to monitoring (nontoxic bait) blocks was universally high, regardless of ground or tree placement. Mongooses were present at all sites, with a greater proportion of plates tracked within the forest than at public-use sites. Cats were present at all forest sites and one of the public-use sites. Presence of the three species did not appear to be linked to human disturbance. Because only 30–40 Puerto Rican parrots survive in the wild, with as few as three pairs nesting in 2002, we concluded that the abundance and pervasiveness of exotic mammalian predators poses a greater threat to the parrots than has been generally acknowledged. This is evidenced by mammalian predation during recent parrot breeding seasons, including six fledglings taken by mongooses and one nest failure from rats during 2000–2003.

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Community-based study to demonstrate the presence and local perspectives of the Critically Endangered Chinese Pangolin Manis pentadactyla in Zhejiang Wuyanling, China

Journal of Threatened Taxa ◽

10.11609/jott.5149.12.5.15547-15556 ◽

2020 ◽

Vol 12 (5) ◽

pp. 15547-15556

Author(s):

Hongying Li ◽

Shusheng Zhang ◽

Ji Zhang ◽

Zupei Lei ◽

Fangdong Zheng ◽

...

Keyword(s):

Mainland China ◽

Infrared Camera ◽

Critically Endangered ◽

Community Based ◽

Illegal Hunting ◽

Critically Endangered Species ◽

The Status ◽

In The Wild ◽

Manis Pentadactyla ◽

Camera Surveillance

Illegal hunting and trading of the Chinese Pangolin Manis pentadactyla has pushed this Critically Endangered species close to extinction. While local reports have suggested its continued presence in mainland China, this has not been confirmed by a research group except for a survey of presumed pangolin burrows in 2004. We conducted a six-month field study using infrared camera surveillance and community questionnaire survey in Zhejiang Wuyanling National Nature Reserve in China, to determine the status of Chinese Pangolins and understand local attitudes towards the conservation of this species. Our study details the first verifiable documentation of two visual records of a Chinese Pangolin in the wild, demonstrating the suitability of pangolin habitat in Wuyanling region, and suggests an increasing awareness and strong willingness in local communities to conserve the Chinese Pangolin.

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Conservation of Britain’s biodiversity: Distribution and status of the Welsh endemic Hieracium breconicola, Beacons Hawkweed (Asteraceae)

British & Irish Botany ◽

10.33928/bib.2021.03.052 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Sarah J. Lee ◽

Timothy C.G. Rich

Keyword(s):

Critically Endangered ◽

Endemic Plant ◽

Conservation Action ◽

Field Surveys ◽

Threat Status ◽

In The Wild

Hieracium breconicola P.D. Sell, Beacons Hawkweed, is a Welsh endemic plant confined to the Brecon Beacons. Field surveys 2009-2020 indicate only one plant survives in one of its three sites. The IUCN threat status is ‘Critically Endangered’; unless conservation action is undertaken soon, this species will soon be extinct in the wild.

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Conservation biology of the critically endangered salamander, Paradactylodon persicus gorganensis (Clergue-Gazeau & Thorn, 1979) (Amphibia: Hynobiidae) in northeastern Iran

Animal Biology ◽

10.1163/15707563-bja10057 ◽

2021 ◽

pp. 1-12

Author(s):

Seyyed Saeed Hosseinian Yousefkhani

Keyword(s):

High Elevation ◽

Quality Parameters ◽

Critically Endangered ◽

Ex Situ ◽

Conservation Action ◽

Agriculture Industry ◽

Negative Effect ◽

In The Wild ◽

Future Viability ◽

Anthropogenic Threats

Abstract Paradactylodon persicus gorganensis is a critically endangered salamander found in northeastern Iran which faces increasing major anthropogenic threats such as agriculture, industry and mining. The aim of the current study is to identify key environmental variables associated with the species’ presence. Also, measuring and comparing the water quality parameters in habitats where P. p. gorganensis is present and absent are the other aims of the study. The results indicate that high pH and dissolved oxygen values have a negative effect on the species’ presence, while its presence was strongly correlated with low mean water temperatures. The species’ range in response to the climate change will shift to the south and east, where areas of high elevation occur, because the species favors cold habitats. This study indicates that it will be particularly important to evaluate the whole range where P. p. gorganensis exists when preparing conservation action plans. It is recommended that ex-situ conservation programs are incorporated into conservation planning for the species, because the number of individuals in the wild is so low and their future viability is fragile.

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The Critically Endangered Myanmar snub-nosed monkey Rhinopithecus strykeri found in the Salween River Basin, China

Oryx ◽

10.1017/s0030605316000934 ◽

2016 ◽

Vol 52 (1) ◽

pp. 134-136 ◽

Cited By ~ 4

Author(s):

Yin Yang ◽

Ying-Ping Tian ◽

Chen-Xiang He ◽

Zhipang Huang ◽

Shao-Hua Dong ◽

...

Keyword(s):

River Basin ◽

Infrared Camera ◽

Critically Endangered ◽

Term Survival ◽

Transect Sampling ◽

In The Wild ◽

Disturbed Forest ◽

Endangered Status ◽

Salween River

AbstractThe Myanmar snub-nosed monkey Rhinopithecus strykeri was discovered in 2010 on the western slopes of the Gaoligong Mountains in the Irrawaddy River basin in Myanmar and subsequently in the same river basin in China, in 2011. Based on 2 years of surveying the remote and little disturbed forest of the Gaoligong Mountains National Nature Reserve in China, with outline transect sampling and infrared camera monitoring, a breeding group comprising > 70 individuals was found on the eastern slopes of the Gaoligong Mountains in the Salween River Basin. Given the Critically Endangered status of this primate (a total of < 950 individuals are estimated to remain in the wild), efforts to protect the relatively undisturbed habitat of this newly discovered population and to prevent hunting are essential for the long-term survival of this species.

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Two new species, two rediscoveries and a range extension in Lachenalia (Asparagaceae: Scilloideae) from southern and western South Africa

Phytotaxa ◽

10.11646/phytotaxa.316.3.5 ◽

2017 ◽

Vol 316 (3) ◽

pp. 261 ◽

Cited By ~ 1

Author(s):

GRAHAM DUNCAN

Keyword(s):

South Africa ◽

New Species ◽

River Valley ◽

Range Extension ◽

Critically Endangered ◽

Western Cape ◽

Two New Species ◽

In The Wild ◽

Northern Cape

Two recently discovered species of Lachenalia from South Africa, Lachenalia barbarae from the Overberg district of the Western Cape and Lachenalia adamii from the Bokkeveld escarpment of the Northern Cape, are described. In addition, details of the rediscovery of two species previously thought to be possibly extinct in the wild, Lachenalia martleyi from the Overberg district in the Western Cape and Lachenalia macgregoriorum from the Bokkeveld plateau in the Northern Cape, are provided, as well as a range extension for the critically endangered Lachenalia moniliformis from the Breede River Valley in the Western Cape.

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Baseline expression of heat-shock proteins (HSPs) of a "thermotolerant" Mediterranean marine species largely influenced by natural temperature fluctuations

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f06-102 ◽

2006 ◽

Vol 63 (9) ◽

pp. 2028-2037 ◽

Cited By ~ 20

Author(s):

Christophe Lejeusne ◽

Thierry Pérez ◽

Vanessa Sarrazin ◽

Pierre Chevaldonné

Keyword(s):

Heat Shock ◽

Experimental Studies ◽

Disease Outbreaks ◽

Temperature Fluctuations ◽

Marine Species ◽

Marine Biodiversity ◽

Expression Variability ◽

In The Wild ◽

Hsp60 Expression ◽

Predictive Approaches

Northwestern Mediterranean warming-related disease outbreaks and species shifts have recently been documented. Biomarkers of short-term effects on the health or resistance of organisms are necessary to assess and understand mechanisms affecting marine biodiversity. Heat-shock protein (HSP) expression was here believed to present finer variations than previously reported in experimental studies, which we tested to assess HSP sensitivity and relevance in the global warming context. One population of the "thermophilic" marine cave mysid Hemimysis margalefi was monitored over 4 years. Three HSPs presented recurrent expression. Among them, HSP50 and HSP60 expressions varied seasonally with environmental temperature. HSP60 expression displayed the greatest variability and was most closely related to temperature fluctuations. Multiple regression showed that while the main stressor was temperature, demographic variables (proportion of immatures, proportion of gravid females) also influenced expression variability. Such a monitoring of HSP baseline expression in a natural population had only rarely been conducted. HSPs are, however, good biomarkers to evaluate the effects of warming episodes or heat stress in the wild. This study provides essential spatial and temporal reference for further experimental and in situ analyses and is a prerequisite to diagnostic and predictive approaches.

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Loss of Predator Discrimination by Critically Endangered Vancouver Island Marmots Within Five Generations of Breeding for Release

Frontiers in Conservation Science ◽

10.3389/fcosc.2021.718562 ◽

2021 ◽

Vol 2 ◽

Author(s):

Graham P. Dixon-MacCallum ◽

Johnathan L. Rich ◽

Natasha Lloyd ◽

Daniel T. Blumstein ◽

Axel Moehrenschlager

Keyword(s):

Vancouver Island ◽

Predator Recognition ◽

Critically Endangered ◽

Species Of Conservation Concern ◽

Mammalian Predators ◽

In Captivity ◽

Two Generations ◽

In The Wild ◽

Conservation Concern ◽

Changes Over Time

Conservation translocations, which involve the intentional movement and release of organisms for conservation benefit, are increasingly required to recover species of conservation concern. In order to maximize post-release survival, and to accomplish conservation translocation objectives, animals must exhibit behaviors that facilitate survival in the wild. The Vancouver Island marmot (Marmota vancouverensis) is a critically endangered endemic in Canada which has been captive-bred for 24 years for reintroductions and reinforcements that have increased the wild population from ~30 to more than 200 individuals. Despite this success many marmots are killed by predators after release and predation represents a major hurdle to full marmot recovery. To better understand if captive-bred marmots are prepared for the novel environment into which they will be released, and to determine whether such suitability changes over time, we presented taxidermy mounts of mammalian predators and non-predators to marmots that were wild-caught, and captive born for between one and five generations. We also examined mortality of offspring from marmots we tested that had been released to the wild. A minimum of 43% of offspring were killed by predators in the wild over 17 years, most by cougars. Marmots in captivity generally responded to taxidermy mounts by decreasing foraging and increasing vigilance, and overall responded more strongly to predators than non-predators, especially wolves. However, marmots in captivity for more than two generations lacked discrimination between cougars, non-predators, and controls, suggesting a rapid loss of predator recognition. This study was only possible because predator-recognition trials were initiated early in the conservation translocation program, and could then be repeated after a number of generations. The finding that changes occurred relatively rapidly (within five generations during which changes in genetic diversity were negligible) suggests that behavioral suitability may deteriorate more rapidly than genetics would suggest. Strategies addressing potential behavior loss should be considered, including sourcing additional wild individuals or pre-release training of captive-born individuals. Subsequently, post-release survival should be monitored to determine the efficacy of behavior-optimization strategies.

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