Are any populations 'safe'? Unexpected reproductive decline in a population of Tasmanian devils free of devil facial tumour disease

2018 ◽  
Vol 45 (1) ◽  
pp. 31 ◽  
Author(s):  
K. A. Farquharson ◽  
R. M. Gooley ◽  
S. Fox ◽  
S. J. Huxtable ◽  
K. Belov ◽  
...  
Keyword(s):  
Conservation Management ◽  
Southern Oscillation ◽  
Demographic Data ◽  
Management Strategies ◽  
Natural Populations ◽  
Significant Decline ◽  
Tasmanian Devil ◽  
Devil Facial Tumour Disease ◽  
In The Wild ◽  
Reproductive Rates

Context Conservation management relies on baseline demographic data of natural populations. For Tasmanian devils (Sarcophilus harrisii), threatened in the wild by two fatal and transmissible cancers (devil facial tumour disease DFTD: DFT1 and DFT2), understanding the characteristics of healthy populations is crucial for developing adaptive management strategies to bolster populations in the wild. Aims Our analysis aims to evaluate contemporary reproductive rates for wild, DFTD-free Tasmanian devil populations, and to provide a baseline with which to compare the outcome of current translocation activities. Methods We analysed 8 years of field-trapping data, including demographics and reproductive rates, across 2004–16, from the largest known DFTD-free remnant population at Woolnorth, Tasmania. Key results Surprisingly, we found a dramatic and statistically significant decline in female breeding rate when comparing data collected from 2004–2009 with data from 2014–2016. Unfortunately we do not have any data from the intermediate years. This decline in breeding rate was accompanied by a subtle but statistically significant decline in litter sizes. These changes were not associated with a change in body condition over the same period. Furthermore, we could not attribute the decline in breeding to a change in population size or sex ratio. Preliminary analysis suggested a possible association between annual breeding rate and coarse measures of environmental variation (Southern Oscillation Index), but any mechanistic associations are yet to be determined. Conclusions The decline in breeding rates was unexpected, so further monitoring and investigation into potential environmental and/or biological reasons for the decline in breeding rate are recommended before the arrival of DFTD at Woolnorth. Implications Our results provide valuable data to support the conservation management of Tasmanian devils in their native range. They also highlight the importance of continued monitoring of ‘safe’ populations, in the face of significant threats elsewhere.

A preliminary study of regeneration in wild populations of threatened endemic Hawaiian palms (Pritchardia; Arecaceae)

2007 ◽  
Vol 13 (1) ◽  
pp. 20 ◽  
Author(s):  
Melany H. Chapin ◽  
Mike Maunder ◽  
Katherine E. Horak
Keyword(s):  
Seed Predation ◽  
Conservation Management ◽  
Management Strategies ◽  
Ecological Change ◽  
Wild Populations ◽  
In The Wild ◽  
Human Colonization ◽  
Preliminary Study ◽  
Term Management

Island floras have been subject to catastrophic changes since human colonization; the Hawaiian Islands exemplify this pattern of species decline and ecological change. Archaeological and historic findings support the former existence of coastal, lowland and interior Pritchardia dominated forests. Wild Pritchardia populations are highly fragmented and exhibit poor or absent regeneration in the wild. This study records seed predation, goat grazing, pig damage, and human harvesting on six wild populations of three species and outlines requirements for the long-term management of wild populations. Only one population of the six studied was found to contain seedlings. Recommended conservation management strategies are outlined.

scholarly journals Modelling nesting site suitability in a population of reintroduced Eurasian black vultures Aegypius monachus in the Grands Causses, France

Oryx ◽  
2013 ◽  
Vol 48 (1) ◽  
pp. 116-124 ◽  
Author(s):  
Jean-Baptiste Mihoub ◽  
Frédéric Jiguet ◽  
Philippe Lécuyer ◽  
Bertrand Eliotout ◽  
François Sarrazin
Keyword(s):  
Habitat Suitability ◽  
Conservation Management ◽  
Management Strategies ◽  
Natural Populations ◽  
Breeding Habitat ◽  
Limiting Factor ◽  
Large Area ◽  
Site Suitability ◽  
Presence Data ◽  
Pine Trees

AbstractDefining habitat selection features and predicting the distribution of species are important for conservation management, and habitat suitability models can provide the statistical framework linking environmental variables to occurrence locations. However, the reliability of such models is restricted for datasets that have limited presence data, which is problematic when population size is low and population dynamics are transient, such as in reintroductions. We characterized and projected nest-site suitability for a black vulture Aegypius monachus population reintroduced in the Grands Causses, France. We performed temporal validations with subsample datasets based on chronological establishment, to assess whether first nests are able to predict subsequent nests. We compared these results to a spatial validation to ensure robustness. Predictions were reliable even with only 10 nest locations. The black vultures reintroduced in the Grands Causses selected pine trees and steep slopes, similar to natural populations elsewhere in Europe. Although our projections were made from only a small number of founders, they are conservative and indicate that a large area in this region is available for nesting and thus availability of breeding habitat is not currently a limiting factor for the species. Our findings will aid the modelling of habitat suitability for further reintroductions. We propose conservation management strategies for this region that integrate socio-economic constraints with the prediction of sites suitable for nesting. Where habitat is the most suitable for black vultures, logging and human activities need to be reduced during the critical breeding stages.

scholarly journals A Tasmanian devil breeding program to support wild recovery

2019 ◽  
Vol 31 (7) ◽  
pp. 1296 ◽  
Author(s):  
C. E. Grueber ◽  
E. Peel ◽  
B. Wright ◽  
C. J. Hogg ◽  
K. Belov
Keyword(s):  
Genetic Diversity ◽  
Reproductive Success ◽  
Genetic Research ◽  
Breeding Program ◽  
Natural Environments ◽  
Tasmanian Devil ◽  
Strategic Approach ◽  
Devil Facial Tumour Disease ◽  
Transmissible Cancer ◽  
In The Wild

Tasmanian devils are threatened in the wild by devil facial tumour disease: a transmissible cancer with a high fatality rate. In response, the Save the Tasmanian Devil Program (STDP) established an ‘insurance population’ to enable the preservation of genetic diversity and natural behaviours of devils. This breeding program includes a range of institutions and facilities, from zoo-based intensive enclosures to larger, more natural environments, and a strategic approach has been required to capture and maintain genetic diversity, natural behaviours and to ensure reproductive success. Laboratory-based research, particularly genetics, in tandem with adaptive management has helped the STDP reach its goals, and has directly contributed to the conservation of the species in the wild. Here we review this work and show that the Tasmanian devil breeding program is a powerful example of how genetic research can be used to understand and improve reproductive success in a threatened species.

scholarly journals Ethyl-Iophenoxic acid as a serum marker for oral baiting of carnivorous marsupials

2021 ◽  
Author(s):  
Ruth Pye ◽  
David S Nichols ◽  
Amy T. Gilbert ◽  
Andrew S Flies
Keyword(s):  
Field Trials ◽  
Serum Marker ◽  
Negative Control ◽  
Vaccine Uptake ◽  
Tasmanian Devil ◽  
Serum Samples ◽  
Baseline Serum ◽  
Wildlife Species ◽  
Devil Facial Tumour Disease ◽  
In The Wild

Context: Ethyl-Iophenoxic acid (Et-IPA) has been widely used as a bait biomarker to determine oral bait consumption by vertebrate wildlife species. Oral bait vaccines have been delivered to numerous wildlife species to protect them from disease. The Tasmanian devil (Sarcophilis harrisii), the largest extant carnivorous marsupial species, is threatened by the transmissible cancers known as devil facial tumour disease (DFTD). Development of a protective DFTD vaccine is underway, and an oral bait has been proposed to deliver the vaccine in the wild. The bait delivery system requires a biomarker that can be detected for several months post-consumption in Tasmanian devils. Aim: To determine the suitability of Et-IPA as a bait biomarker in the Tasmanian devil. Method: Two Tasmanian devils were fed 50 mg Et-IPA (4.5 to 7.1 mg Et-IPA/kg bodyweight). Liquid chromatography with tandem mass spectrometry (LC-MS/-MS) was used to directly measure Et-IPA in baseline serum samples and samples collected on days 1, 14, 26 and 56 post-baiting. Key results: Both devils retained serum Et-IPA concentrations at two orders of magnitude above negative control sera when this study concluded. Conclusions: Et-IPA is a useful bait biomarker for Tasmanian devils and can be included in future DFTD bait vaccine field trials to determine bait vaccine uptake.

scholarly journals Status Of Endemic Plants Of Bangladesh And Conservation Management Strategies

2013 ◽  
Vol 2 (1) ◽  
pp. 231-249
Author(s):  
M Atiqur Rahman ◽  
M Enamur Rashid
Keyword(s):  
Sustainable Management ◽  
Conservation Management ◽  
Conservation Status ◽  
Management Strategies ◽  
Species Conservation ◽  
Endemic Plants ◽  
Conservation Priority ◽  
The Status ◽  
In The Wild ◽  
Total Species

The present study was aimed at recognizing the status of 28 endemic plants of Bangladesh and determining their conservation management strategies. These endemics belong to 17 angiosperm families and constitute about 0.78% of the total species of the country. Of these endemics, 2 species were least concern, 10 rare and 7 endangered, and need to give immediate conservation priority. Another 9 endemics were assessed to be extinct since no report of collection for more than 100 years was available and could not be traced in the wild. An enumeration of these endemics is presented, each cited with updated nomenclature, bangla names, type, habit, ecology, potential values, places and status of occurrence, threats to the species, conservation status for sustainable management strategies. List of examined specimens of these endemics, wherever available, is also provided. Photographs of 24 endemics are also presented. International Journal of Environment, Volume-2, Issue-1, Sep-Nov 2013, Pages 231-249 DOI: http://dx.doi.org/10.3126/ije.v2i1.9224

scholarly journals Extensive population decline in the Tasmanian devil predates European settlement and devil facial tumour disease

2014 ◽  
Vol 10 (11) ◽  
pp. 20140619 ◽  
Author(s):  
Anna Brüniche-Olsen ◽  
Menna E. Jones ◽  
Jeremy J. Austin ◽  
Christopher P. Burridge ◽  
Barbara R. Holland
Keyword(s):  
Genetic Diversity ◽  
Environmental Changes ◽  
Southern Oscillation ◽  
Demographic History ◽  
Population Decline ◽  
Tasmanian Devil ◽  
Term Survival ◽  
Temporal Sampling ◽  
Low Genetic Diversity ◽  
Devil Facial Tumour Disease

The Tasmanian devil ( Sarcophilus harrisii ) was widespread in Australia during the Late Pleistocene but is now endemic to the island of Tasmania. Low genetic diversity combined with the spread of devil facial tumour disease have raised concerns for the species’ long-term survival. Here, we investigate the origin of low genetic diversity by inferring the species' demographic history using temporal sampling with summary statistics, full-likelihood and approximate Bayesian computation methods. Our results show extensive population declines across Tasmania correlating with environmental changes around the last glacial maximum and following unstable climate related to increased ‘El Niño–Southern Oscillation’ activity.

scholarly journals Lessons from the Looming Extinction of the Tasmanian Devil

2008 ◽  
Vol 14 (3) ◽  
pp. 151 ◽  
Author(s):  
D. Lunney ◽  
M. Jones ◽  
H. McCullum
Keyword(s):  
Cancer Cells ◽  
Captive Breeding ◽  
Active Management ◽  
Tasmanian Devil ◽  
Population Bottlenecks ◽  
Low Genetic Diversity ◽  
Devil Facial Tumour Disease ◽  
In The Wild ◽  
Breeding Programmes ◽  
Infectious Cancer

Extinction in the wild is now regarded as likely for the Tasmanian Devil Sarcophilus harrissi. In 1996, a disease, Devil Facial Tumour Disease (DFTD), was seen in a Devil in the wild. By mid-2008, the population had declined by about 70%, and the disease was spreading rapidly from east to west across Tasmania. DFTD is an infectious cancer, passed from one Devil to another principally, or entirely, by biting. The bite implants the cancer cells; the low genetic diversity in the Tasmanian Devil population from previous population bottlenecks or selective sweeps means that those cancer cells are not recognized by the immune system and the cancer grows in the infected Devil. Estimates of the time to extinction in the wild range from about 20 to 35 years. If, however, there are resistant genotypes within the Devil population then extinction in the wild may be averted, with numbers augmented through captive breeding programmes and active management to spread these genotypes in the wild.

scholarly journals Disease and the dynamics of extinction

2012 ◽  
Vol 367 (1604) ◽  
pp. 2828-2839 ◽  
Author(s):  
Hamish McCallum
Keyword(s):  
Infectious Diseases ◽  
Disease Transmission ◽  
Management Strategies ◽  
Host Density ◽  
Habitat Destruction ◽  
Broad Host Range ◽  
Tasmanian Devil ◽  
Management Options ◽  
Reservoir Species ◽  
Devil Facial Tumour Disease

Invading infectious diseases can, in theory, lead to the extinction of host populations, particularly if reservoir species are present or if disease transmission is frequency-dependent. The number of historic or prehistoric extinctions that can unequivocally be attributed to infectious disease is relatively small, but gathering firm evidence in retrospect is extremely difficult. Amphibian chytridiomycosis and Tasmanian devil facial tumour disease (DFTD) are two very different infectious diseases that are currently threatening to cause extinctions in Australia. These provide an unusual opportunity to investigate the processes of disease-induced extinction and possible management strategies. Both diseases are apparently recent in origin. Tasmanian DFTD is entirely host-specific but potentially able to cause extinction because transmission depends weakly, if at all, on host density. Amphibian chytridiomycosis has a broad host range but is highly pathogenic only to some populations of some species. At present, both diseases can only be managed by attempting to isolate individuals or populations from disease. Management options to accelerate the process of evolution of host resistance or tolerance are being investigated in both cases. Anthropogenic changes including movement of diseases and hosts, habitat destruction and fragmentation and climate change are likely to increase emerging disease threats to biodiversity and it is critical to further develop strategies to manage these threats.

Genetic analysis of scat samples to inform conservation of the Tasmanian devil

2020 ◽  
Vol 40 (3) ◽  
pp. 492-504
Author(s):  
Catherine E. Grueber ◽  
Rowena Chong ◽  
Rebecca M. Gooley ◽  
Elspeth A. McLennan ◽  
Vanessa R. Barrs ◽  
...  
Keyword(s):  
Animal Species ◽  
Conservation Management ◽  
Management Strategies ◽  
Species Conservation ◽  
Conservation Strategy ◽  
Tasmanian Devil ◽  
Scat Analysis ◽  
Intestinal Microbes ◽  
The Devil

Recent advances in molecular genetics have enabled a great deal of information about species to be obtained from analysis of non-invasively collected samples such as scat. Scat provides genetic information via residual host DNA on the outside of the scat, via characterising the genetic makeup of intestinal microbes that are present in the scat, or by examining the DNA remnants of prey items that have passed through the animal’s digestive tract. In this review, we provide a case study to demonstrate how these approaches are being used to better understand the threatened Tasmanian devil in the landscape, and to support the species’ conservation. Scat analysis enables us to quantify the genetic diversity of remote populations, where trapping is logistically challenging. We are beginning to learn how conservation management impacts the microbiome of threatened species, and investigate how various management strategies may be impacting the diverse array of bacteria and viruses that devils, like all animal species, are host to. We are using scat samples to better understand the interaction between devils and other animals in their environment by learning more about what they eat. We explore the strengths and challenges of these approaches by comparing our work to that conducted in other species. Finally, we provide specific examples of how our results are being integrated into conservation strategy for the devil.

scholarly journals Low major histocompatibility complex diversity in the Tasmanian devil predates European settlement and may explain susceptibility to disease epidemics

2013 ◽  
Vol 9 (1) ◽  
pp. 20120900 ◽  
Author(s):  
Katrina Morris ◽  
Jeremy J. Austin ◽  
Katherine Belov
Keyword(s):  
Major Histocompatibility Complex ◽  
Tasmanian Devil ◽  
Major Histocompatibility ◽  
European Settlement ◽  
Low Genetic Diversity ◽  
Histocompatibility Complex ◽  
Devil Facial Tumour Disease ◽  
History Of ◽  
Mhc Diversity ◽  
Disease Epidemics

The Tasmanian devil ( Sarcophilus harrisii ) is at risk of extinction owing to the emergence of a contagious cancer known as devil facial tumour disease (DFTD). The emergence and spread of DFTD has been linked to low genetic diversity in the major histocompatibility complex (MHC). We examined MHC diversity in historical and ancient devils to determine whether loss of diversity is recent or predates European settlement in Australia. Our results reveal no additional diversity in historical Tasmanian samples. Mainland devils had common modern variants plus six new variants that are highly similar to existing alleles. We conclude that low MHC diversity has been a feature of devil populations since at least the Mid-Holocene and could explain their tumultuous history of population crashes.

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