scholarly journals Demographic and genetic factors in the recovery or demise ofex situpopulations following a severe bottleneck in fifteen species of Hawaiian tree snails

PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1406 ◽  
Author(s):  
Melissa R. Price ◽  
David Sischo ◽  
Mark-Anthony Pascua ◽  
Michael G. Hadfield
Keyword(s):  
Life History Traits ◽  
Human Impacts ◽  
Ex Situ ◽  
Wild Populations ◽  
Captive Populations ◽  
Introduced Predators ◽  
In Captivity ◽  
Term Data

Wild populations of endangered Hawaiian tree snails have declined precipitously over the last century due to introduced predators and other human impacts. Life history traits, such as very low fecundity (<5 offspring per year across taxa) and maturity at approximately four years of age have made recovery difficult. Conservation efforts such asin situpredator-free enclosures may increase survival to maturity by protecting offspring from predation, but no long-term data existed prior to this study demonstrating the demographic and genetic parameters necessary to maintain populations within those enclosures. We evaluated over 20 years of evidence for the dynamics of survival and extinction in captiveex situpopulations of Hawaiian tree snails established from wild-collected individuals. From 1991 to 2006, small numbers of snails (<15) from fifteen species were collected from the wild to initiate captive-reared populations as a hedge against extinction. This small number of founders resulted in a severe bottleneck in each of the captive-reared populations. We identified key demographic parameters that predicted population recovery from this bottleneck. Species with captive populations that produced between two and four offspring per adult per year and had 20–50% of those offspring survive to maturity recovered to numbers above 100 individuals, and maintained viable populations following a decline that occurred between 2009 and 2014. Those populations that had less than two offspring per adult per year and less than 20% survival to maturity did not reach 100 individuals in captivity, and many of these populations died out during the recent decline. We suggest that small reductions in fitness may contribute to extirpation in taxa with inherently low fecundity, by keeping populations below a threshold number essential to long-term recovery. Futureex situpopulations should be founded with no less than 15 adults, and maintained in conditions closely approximating the temperature and humidity of source locations to optimize fitness. Permanent translocations of wild populations for conservation purposes will be more likely to succeed with greater than 100 adults, and should be limited to locations with a similar climate to source locations.

scholarly journals The decline and conservation management of the threatened endemic palms of the Mascarene Islands

Oryx ◽  
2002 ◽  
Vol 36 (1) ◽  
pp. 56-65 ◽  
Author(s):  
Mike Maunder ◽  
Wayne Page ◽  
John Mauremootoo ◽  
Richard Payendee ◽  
Yousoof Mungroo ◽  
...  
Keyword(s):  
Large Scale ◽  
Conservation Management ◽  
Conservation Status ◽  
Iucn Red List ◽  
Ex Situ ◽  
Population Fragmentation ◽  
Wild Populations ◽  
Mascarene Islands

Abstract The conservation status of the five genera and 11 species of palm endemic to the Mascarene Islands (Mauritius, La Réunion and Rodriques) are reviewed. All species are threatened with extinction; nine taxa are classified as Critically Endangered and four as Endangered on the 2000 IUCN Red List. Two taxa survive as single wild specimens (Hyophorbe amaricaulis and Dictyosperma album var. conjugatum); an additional seven taxa have wild populations of 100 or fewer. Although the historical phase of large-scale forest clearance has passed, the remaining palm populations in the Mascarenes are under threat from the effects of population fragmentation, invasive plants and animals, and high levels of seed predation that prevent natural regeneration. The advantages of in situ management for the recovery of these palm populations are discussed. Without a long-term conservation programme, utilising both in situ and ex situ management, extinction of wild populations will occur.

scholarly journals Older mothers produce more successful daughters

2020 ◽  
Vol 117 (9) ◽  
pp. 4809-4814 ◽  
Author(s):  
Svenja B. Kroeger ◽  
Daniel T. Blumstein ◽  
Kenneth B. Armitage ◽  
Jane M. Reid ◽  
Julien G. A. Martin
Keyword(s):  
Reproductive Success ◽  
Life History Traits ◽  
Lifetime Reproductive Success ◽  
Wild Populations ◽  
Substantial Variation ◽  
Older Mothers ◽  
Lower Elevation ◽  
In The Wild ◽  
Term Data

Annual reproductive success and senescence patterns vary substantially among individuals in the wild. However, it is still seldom considered that senescence may not only affect an individual but also affect age-specific reproductive success in its offspring, generating transgenerational reproductive senescence. We used long-term data from wild yellow-bellied marmots (Marmota flaviventer) living in two different elevational environments to quantify age-specific reproductive success of daughters born to mothers differing in age. Contrary to prediction, daughters born to older mothers had greater annual reproductive success on average than daughters born to younger mothers, and this translated into greater lifetime reproductive success. However, in the favorable lower elevation environment, daughters born to older mothers also had greater age-specific decreases in annual reproductive success. In the harsher higher elevation environment on the other hand, daughters born to older mothers tended to die before reaching ages at which such senescent decreases could be observed. Our study highlights the importance of incorporating environment-specific transgenerational parent age effects on adult offspring age-specific life-history traits to fully understand the substantial variation observed in senescence patterns in wild populations.

Laying date of marsh tits Parus palustris in relation to climate change

Biologia ◽  
2006 ◽  
Vol 61 (5) ◽  
Author(s):  
Zdravko Dolenec
Keyword(s):  
Climate Change ◽  
Life History Traits ◽  
Laying Date ◽  
Bird Breeding ◽  
Spring Temperatures ◽  
The Mean ◽  
The Relationship ◽  
Marsh Tit ◽  
Term Data

AbstractIncreasing evidence suggests that climate change affects bird breeding phenology and other life-history traits of wildlife. This study is based on the mean spring temperatures (February, March, April) and laying dates of first eggs of the marsh tit Parus palustris. We collected data from 1984 to 2004 for the Mokrice area in NW Croatia. Correlation between laying date and mean spring temperatures was significant. The relationship between mean laying date (y) and air temperature (x) can be expressed as y = 44.69 − 2.08x. Results indicate that spring temperatures are a good predictor of timing of laying eggs. Such long-term data could than be used in order to assess the effects on biological systems if human activities influence climate.

Calcium effects on life-history traits in a wild population of the great tit (Parus major): analysis of long-term data at several spatial scales

Oecologia ◽  
2008 ◽  
Vol 159 (2) ◽  
pp. 463-472 ◽  
Author(s):  
Teddy Albert Wilkin ◽  
Andrew G. Gosler ◽  
Dany Garant ◽  
S. James Reynolds ◽  
Ben C. Sheldon
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Wild Population ◽  
Spatial Scales ◽  
Parus Major ◽  
Great Tit ◽  
Calcium Effects ◽  
Term Data

scholarly journals Habitat and social context affect memory phenotype, exploration and covariance among these traits

2018 ◽  
Vol 373 (1756) ◽  
pp. 20170291 ◽  
Author(s):  
Sarah Dalesman
Keyword(s):  
Individual Differences ◽  
Cognitive Abilities ◽  
Lymnaea Stagnalis ◽  
Memory Formation ◽  
Long Term Memory ◽  
Wild Populations ◽  
In Captivity ◽  
Specific Trait ◽  
Context Specific

Individual differences in cognitive ability are predicted to covary with other behavioural traits such as exploration and boldness. Selection within different habitats may act to either enhance or break down covariance among traits; alternatively, changing the environmental context in which traits are assessed may result in plasticity that alters trait covariance. Pond snails, Lymnaea stagnalis , from two laboratory strains (more than 20 generations in captivity) and F1 laboratory reared from six wild populations were tested for long-term memory and exploration traits (speed and thigmotaxis) following maintenance in grouped and isolated conditions to determine if isolation: (i) alters memory and exploration; and (ii) alters covariance between memory and exploration. Populations that demonstrated strong memory formation (longer duration) under grouped conditions demonstrated weaker memory formation and reduced both speed and thigmotaxis following isolation. In wild populations, snails showed no relationship between memory and exploration in grouped conditions; however, following isolation, exploration behaviour was negatively correlated with memory, i.e. slow-explorers showing low levels of thigmotaxis formed stronger memories. Laboratory strains demonstrated no covariance among exploration traits and memory independent of context. Together these data demonstrate that the relationship between cognition and exploration traits can depend on both habitat and context-specific trait plasticity. This article is part of the theme issue ‘Causes and consequences of individual differences in cognitive abilities’.

scholarly journals Propagation of Threatened Nepenthes khasiana: Methods and Precautions

2015 ◽  
Vol 7 (3) ◽  
pp. 313-315
Author(s):  
Jibankumar S. KHURAIJAM ◽  
Rup K. ROY
Keyword(s):  
Plant Species ◽  
Threatened Species ◽  
Ex Situ Conservation ◽  
Ex Situ ◽  
In The Wild ◽  
Propagation Technique ◽  
Subsequent Propagation ◽  
Nepenthes Khasiana

Ex-situ conservation is an important key in the management of rare, endangered and threatened (RET) plant species and its effectiveness depends on several factors. Maintenance of viable germplasm and its subsequent propagation plays an important role in long term conservation of many RET species. Nepenthes khasiana is a rare and gravely threatened species in the wild due to over-collection and other threats. The species needs urgent in-situ and ex-situ conservation. Development of easy to propagate techniques would pave faster multiplication for its use of educational, medicinal and horticultural purpose. In the present paper, successful propagation technique of Nepenthes khasiana through seeds is demonstrated along with detailed information on precautions to be taken during the adoption of the techniques.

scholarly journals Long-term trends in wild-capture and population dynamics point to an uncertain future for captive elephants

2019 ◽  
Vol 286 (1899) ◽  
pp. 20182810 ◽  
Author(s):  
John Jackson ◽  
Dylan Z. Childs ◽  
Khyne U. Mar ◽  
Win Htut ◽  
Virpi Lummaa
Keyword(s):  
Population Dynamics ◽  
Wild Populations ◽  
Birth Rates ◽  
As Species ◽  
In Captivity ◽  
Elephant Population ◽  
Long Term Trends ◽  
Uncertain Future ◽  
Primary Focus

Maintaining sustainable populations in captivity without supplementation through wild-capture is a major challenge in conservation that zoos and aquaria are working towards. However, the capture of wild animals continues for many purposes where conservation is not the primary focus. Wild-capture hinders long-term conservation goals by reducing remaining wild populations, but the direct and long-term indirect consequences of wild-capture for captive population viability are rarely addressed using longitudinal data. We explored the implications of changes in wild-capture on population dynamics in captivity over 54 years using a multi-generational studbook of working Asian elephants ( Elephas maximus ) from Myanmar, the largest remaining captive elephant population. Here we show that population growth and birth rates declined between 1960 and 2014 with declines in wild-capture. Importantly, wild-caught females had reduced birth rates and a higher mortality risk. However, despite the disadvantages of wild-capture, the population may not be sustainable without it, with immediate declines owing to an unstable age-structure that may last for 50 years. Our results highlight the need to assess the long-term demographic consequences of wild-capture to ensure the sustainability of captive and wild populations as species are increasingly managed and conserved in altered or novel environments.

scholarly journals Mitigating Batrachochytrium salamandrivorans in Europe

2019 ◽  
Vol 40 (3) ◽  
pp. 265-290 ◽  
Author(s):  
Valarie Thomas ◽  
Yu Wang ◽  
Pascale Van Rooij ◽  
Elin Verbrugghe ◽  
Vojtech Baláž ◽  
...  
Keyword(s):  
Ex Situ Conservation ◽  
Preventive Measures ◽  
Public Awareness ◽  
Ex Situ ◽  
Chytrid Fungus ◽  
Population Declines ◽  
Batrachochytrium Salamandrivorans ◽  
Mitigation Methods

Abstract The infectious chytrid fungus Batrachochytrium salamandrivorans (Bsal) has been responsible for severe population declines of salamander populations in Europe. Serious population declines and loss of urodelan diversity may occur if appropriate action is not taken to mitigate against the further spread and impact of Bsal. We provide an overview of several potential mitigation methods, and describe their possible advantages and limitations. We conclude that long-term, context-dependent, multi-faceted approaches are needed to successfully mitigate adverse effects of Bsal, and that these approaches should be initiated pre-arrival of the pathogen. The establishment of ex situ assurance colonies, or management units, for species threatened with extinction, should be considered as soon as possible. While ex situ conservation and preventive measures aimed at improving biosecurity by limiting amphibian trade may be implemented quickly, major challenges that lie ahead are in designing in situ disease containment and mitigation post-arrival and in increasing public awareness.

scholarly journals Capture from the wild has long-term costs on reproductive success in Asian elephants

2019 ◽  
Vol 286 (1912) ◽  
pp. 20191584 ◽  
Author(s):  
Mirkka Lahdenperä ◽  
John Jackson ◽  
Win Htut ◽  
Virpi Lummaa
Keyword(s):  
Elephas Maximus ◽  
Negative Effects ◽  
Asian Elephants ◽  
Lifetime Fitness ◽  
Life History Data ◽  
Captive Populations ◽  
In Captivity ◽  
Fitness Measures ◽  
Long Term Consequences

Capturing wild animals is common for conservation, economic or research purposes. Understanding how capture itself affects lifetime fitness measures is often difficult because wild and captive populations live in very different environments and there is a need for long-term life-history data. Here, we show how wild capture influences reproduction in 2685 female Asian elephants ( Elephas maximus ) used in the timber industry in Myanmar. Wild-caught females demonstrated a consistent reduction in breeding success relative to captive-born females, with significantly lower lifetime reproduction probabilities, lower breeding probabilities at peak reproductive ages and a later age of first reproduction. Furthermore, these negative effects lasted for over a decade, and there was a significant influence on the next generation: wild-caught females had calves with reduced survival to age 5. Our results suggest that wild capture has long-term consequences for reproduction, which is important not only for elephants, but also for other species in captivity.

scholarly journals Long-term conservation of potato genetic resources: Methods and status of conservation

2019 ◽  
pp. 717-725
Author(s):  
Jane Muthoni ◽  
Hussein Shimelis ◽  
Rob Melis
Keyword(s):  
Genetic Resources ◽  
Slow Growth ◽  
Plant Genetic Resources ◽  
Ex Situ ◽  
Growth Media ◽  
Medium Term ◽  
Natural Habitats

Plant genetic resources (PGRs) play an important role in agriculture, environment protection, cultural property and trade; they need to be conserved. There are two fundamental approaches for the conservation of PGRs: in situ and ex situ. In situ conservation is the conservation of ecosystems and natural habitats and the maintenance and recovery of viable populations of species in their natural surroundings. Ex situ preservation is the storage of seeds or plant materials under artificial conditions to maintain their long term viability and availability for use. Genebanks employ seed storage, field collections of living plants and in vitro storage (tissue culture or cryopreservation) for ex situ preservation of PGR. Storage of orthodox seeds, which are tolerant to low moisture content and low temperatures at appropriate temperature and humidity, is the most convenient ex situ conservation method. Plants that produce recalcitrant seeds or non-viable seeds are conserved in field genebanks as well as in-vitro in slow growth media for short-to-medium term and cryopreservation in liquid nitrogen at -1960C for long-term periods. Cryopreservation is very expensive and needs trained personnel; this could explain why this method is rarely used for conservation of plant genetic resources in most developing countries. Potato tubers are bulky and highly perishable; the crop is generally conserved as clones either in field genebanks (with annual replanting), in-vitro conservation in slow growth media for short-to-medium term and cryopreservation for long term. Field genebanks are expensive to maintain and the crop is exposed to many dangers; hence, cryopreservation is the only feasible method for long term conservation. However, given the high cost of cryopreservation, long-term conservation of potato genetic resources is poorly developed in most resource-poor countries leading to high rates of genetic erosion. This paper looks into the various methods that that can be applied to conserve potato genetic resources and the status of conservation of potatoes in major genebanks and some countries.

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