A management strategy for the long-term conservation of the Endangered sand-dune lizard Liolaemus multimaculatus in the Pampean coastal dunes of Argentina

AbstractThe sand-dune lizard Liolaemus multimaculatus is an Endangered species endemic to the Pampean coastal dunes of Argentina. To inform the development of a future Action Plan for this species, we investigated the demography and conservation status of all remaining populations, and we suggest management actions appropriate to local needs. We used population viability analysis to assess extinction risk in three inbreeding scenarios and estimate the minimum viable population and the minimum area requirement. To assess the current status of each local population, we used information related to population size, human pressure and connectivity. The results were then used to set and prioritize conservation management actions at local level. Our models indicated that populations of > 2,400 individuals would be viable in the long term and that inbreeding depression has a strong effect on extinction risk. The southern patches of coastal dune contain the largest populations of sand-dune lizards, and they are also better connected and less threatened. We suggest land protection as the priority management action for populations larger than the minimum viable population, whereas habitat recovery, when possible, should be the priority for patches of coastal dune smaller than the minimum area requirement. Supplementation with a small number of individuals could stabilize unviable populations but should be considered only in certain situations.The long-term conservation of the sand-dune lizard will be feasible only if a conservation action plan is developed and implemented.

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Minimum viable population size for lake sturgeon (Acipenser fulvescens) using an individual-based model of demographics and genetics

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f10-129 ◽

2011 ◽

Vol 68 (1) ◽

pp. 62-73 ◽

Cited By ~ 18

Author(s):

Amy M. Schueller ◽

Daniel B. Hayes

Keyword(s):

Population Size ◽

Inbreeding Depression ◽

Extinction Risk ◽

Lake Sturgeon ◽

Acipenser Fulvescens ◽

Demographic Stochasticity ◽

Individual Based Model ◽

Viable Population ◽

Minimum Viable Population Size ◽

Minimum Viable Population

Population viability analysis is a useful tool to explore the relationship between extinction risk and population size, but often does not include genetic factors. Our objectives were to determine minimum viable population size (MVP) for lake sturgeon ( Acipenser fulvescens ) and examine how inbreeding depression may affect MVP. Our individual-based model incorporated inbreeding depression in two ways: individuals with inbreeding coefficients above a threshold experienced inbreeding depression (threshold), and individuals experienced inbreeding depression at a rate related to their inbreeding coefficient (gradual). Three mechanisms relating inbreeding to fitness were explored (young-of-the-year (YOY) viability, post-YOY viability, number of progeny). The criterion we used to determine MVP was a 5% chance of extinction over 250 years. The estimated MVP without inbreeding effects was 80 individuals. For some scenarios incorporating inbreeding, MVP did not change, but for others, MVP was substantially higher, reaching values up to 1800. Results demonstrate that extinction risk and MVP can be influenced by both demographic stochasticity and inbreeding depression. This research should inform management by determining MVP and how inbreeding, which is expected to accrue in remnant populations because of generations of low abundance, may affect MVP.

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Minimum viable population sizes and global extinction risk are unrelated

Ecology Letters ◽

10.1111/j.1461-0248.2006.00883.x ◽

2006 ◽

Vol 9 (4) ◽

pp. 375-382 ◽

Cited By ~ 89

Author(s):

Barry W. Brook ◽

Lochran W. Traill ◽

Corey J. A. Bradshaw

Keyword(s):

Extinction Risk ◽

Global Extinction ◽

Viable Population ◽

Population Sizes ◽

Minimum Viable Population

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Genetic signature of immigrants and their effect on genetic diversity in the recently established Scandinavian wolf population

Conservation Genetics ◽

10.1007/s10592-021-01423-5 ◽

2021 ◽

Author(s):

Mikael Åkesson ◽

Øystein Flagstad ◽

Jouni Aspi ◽

Ilpo Kojola ◽

Olof Liberg ◽

...

Keyword(s):

Genetic Diversity ◽

Canis Lupus ◽

Animal Species ◽

Allelic Richness ◽

A Priori ◽

Management Actions ◽

Viable Population ◽

Population Sizes ◽

Source Populations

AbstractTransboundary connectivity is a key component when conserving and managing animal species that require large areas to maintain viable population sizes. Wolves Canis lupus recolonized the Scandinavian Peninsula in the early 1980s. The population is geographically isolated and relies on immigration to not lose genetic diversity and to maintain long term viability. In this study we address (1) to what extent the genetic diversity among Scandinavian wolves has recovered during 30 years since its foundation in relation to the source populations in Finland and Russia, (2) if immigration has occurred from both Finland and Russia, two countries with very different wolf management and legislative obligations to ensure long term viability of wolves, and (3) if immigrants can be assumed to be unrelated. Using 26 microsatellite loci we found that although the genetic diversity increased among Scandinavian wolves (n = 143), it has not reached the same levels found in Finland (n = 25) or in Russia (n = 19). Low genetic differentiation between Finnish and Russian wolves, complicated our ability to determine the origin of immigrant wolves (n = 20) with respect to nationality. Nevertheless, based on differences in allelic richness and private allelic richness between the two countries, results supported the occurrence of immigration from both countries. A priori assumptions that immigrants are unrelated is non-advisable, since 5.8% of the pair-wise analyzed immigrants were closely related. To maintain long term viability of wolves in Northern Europe, this study highlights the potential and need for management actions that facilitate transboundary dispersal.

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Population fragmentation causes inadequate gene flow and increases extinction risk

10.1093/oso/9780198783398.003.0005 ◽

2017 ◽

Author(s):

Richard Frankham ◽

Jonathan D. Ballou ◽

Katherine Ralls ◽

Mark D. B. Eldridge ◽

Michele R. Dudash ◽

...

Keyword(s):

Gene Flow ◽

Extinction Risk ◽

Random Mating ◽

Large Population ◽

Isolated Population ◽

Population Fragmentation ◽

Single Population ◽

Total Size ◽

Limited Gene Flow

Most species now have fragmented distributions, often with adverse genetic consequences. The genetic impacts of population fragmentation depend critically upon gene flow among fragments and their effective sizes. Fragmentation with cessation of gene flow is highly harmful in the long term, leading to greater inbreeding, increased loss of genetic diversity, decreased likelihood of evolutionary adaptation and elevated extinction risk, when compared to a single population of the same total size. The consequences of fragmentation with limited gene flow typically lie between those for a large population with random mating and isolated population fragments with no gene flow.

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Evaluation of Minimum Viable Population Size and Conservation Status of the Long-furred Woolly Mouse Opossum Micoureus paraguayanus: An Endemic Marsupial of the Atlantic Forest

Biodiversity and Conservation ◽

10.1007/s10531-004-5019-8 ◽

2006 ◽

Vol 15 (5) ◽

Cited By ~ 12

Author(s):

Daniel Brito ◽

Gustavo A. B. da Fonseca

Keyword(s):

Population Size ◽

Atlantic Forest ◽

Conservation Status ◽

Viable Population ◽

Minimum Viable Population Size ◽

Minimum Viable Population

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No evidence for interspecific interactions between plants in the first stage of succession on coastal dunes in subarctic Quebec, Canada

Canadian Journal of Botany ◽

10.1139/b97-100 ◽

1997 ◽

Vol 75 (6) ◽

pp. 902-915 ◽

Cited By ~ 19

Author(s):

Gilles Houle

Keyword(s):

Plant Biomass ◽

Interspecific Interactions ◽

Regional Climate ◽

Salt Spray ◽

Coastal Dunes ◽

Growing Season ◽

Coastal Dune ◽

Dune System ◽

Abiotic Conditions ◽

Herbaceous Perennials

Coastal dunes are very dynamic systems, particularly where the coast is rising as a result of isostatic rebound. In those environments, succession proceeds from plants highly tolerant to sand accumulation, salt spray, and low nutrient availability to less disturbance-tolerant and stress-tolerant, more nutrient-demanding, and supposedly more competitive species. In the subarctic, the regional climate exacerbates the stresses imposed by local abiotic conditions on the dunes. I hypothesized that facilitation would be particularly significant on the foredune of subarctic coastal dune systems because of intense stresses (local and regional) and frequent disturbance in the form of sand deposition. Belowground and aboveground plant biomass was sampled at three different periods during the 1990 growing season along transects perpendicular to the shoreline on a coastal dune system in subarctic Quebec (Canada). The three herbaceous perennials found on the foredune (Honckenya peploides, Elymus mollis, and Lathyrus japonicus) were segregated in time during the growing season and in space along the topographical gradient. The biomass of Honckenya, the first species encountered as one progresses from the upper part of the beach towards the foredune ridge, was not correlated to substrate physicochemistry. However, the biomass of Elymus and that of Lathyrus, the next two species to appear along the flank of the foredune, were related to pH, Mg, Na, and Cl (negatively), and to P and Ca (positively). These results suggest variable linkages between substrate physicochemistry and plant species along the foredune, possibly in relation to species-specific tolerance for abiotic conditions and requirements for substrate resources or to microscale influence of the plants themselves on substrate physicochemistry. Removal experiments carried out over 2 years revealed only one significant unidirectional interaction between these three species along the topographical gradient, and little plant control over abiotic variables (e.g., soil temperature, wind velocity, and photosynthetically active radiation). Early primary succession on subarctic coastal dunes (and elsewhere) appears to be under the control of strong limiting abiotic conditions. As plants slowly gain more control over the physical environment, interspecific interactions (positive and negative) may become more significant. Key words: Elymus mollis, facilitation, Honckenya peploides, inhibition, Lathyrus japonicus, removal experiment, succession, tolerance.

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The “ReDune” index (Restoration of coastal Dunes Index) to assess the need and viability of coastal dune restoration

Ecological Indicators ◽

10.1016/j.ecolind.2014.10.017 ◽

2015 ◽

Vol 49 ◽

pp. 178-187 ◽

Cited By ~ 12

Author(s):

Debora Lithgow ◽

M. Luisa Martínez ◽

Juan B. Gallego-Fernández

Keyword(s):

Coastal Dunes ◽

Coastal Dune ◽

Dune Restoration

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Long-term spatio-temporal expansion of the native-invasive Retama monosperma on coastal dunes: Importance of land-use and natural dispersal vectors

Flora ◽

10.1016/j.flora.2013.04.001 ◽

2013 ◽

Vol 208 (4) ◽

pp. 259-267 ◽

Cited By ~ 3

Author(s):

Sara Muñoz-Vallés ◽

Juan B. Gallego-Fernández ◽

Claudia Dellafiore ◽

Jesús Cambrollé

Keyword(s):

Land Use ◽

Coastal Dunes ◽

Dispersal Vectors ◽

Retama Monosperma ◽

Spatio Temporal ◽

Native Invasive ◽

Natural Dispersal

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Pans in humus podzols (Humods and Aquods) in coastal southern Queensland

Soil Research ◽

10.1071/sr9960161 ◽

1996 ◽

Vol 34 (1) ◽

pp. 161 ◽

Cited By ~ 13

Author(s):

CH Thompson ◽

EM Bridges ◽

DA Jenkins

Keyword(s):

Soil Depth ◽

Sand Dunes ◽

Coastal Dunes ◽

Particle Packing ◽

Sand Mining ◽

Coastal Sand Dunes ◽

Organic Complex ◽

Coastal Sand ◽

Coastal Lowlands

An exploratory examination has been made of three different kinds of hardpans found in humus podzols (Humods and Aquods) of the coastal lowlands of southern Queensland, by means of slaking tests, a reactive aluminium test, acid oxalate and pyrophosphate extractions and electron microscopy. Samples from three indurated layers exposed by erosion or sand-mining in large coastal dunes were included for comparison. The investigation confirmed that, a pan in a bleached A2 (albic E) horizon is most likely caused by particle packing and that a pan in a black B2h (spodic) horizon is cemented by an aluminium-organic complex. Yellow-brown pans underlying black organic pans (spodic horizons) were found to be cemented by both a proto-imogolite/allophane complex and an organic substance. An inorganic reactive Al complex differing from the proto-imogolite allophane recorded in the overlying giant podzols appeared to be main cement of three indurated layers in the nearby coastal sand dunes. Mechanical disturbance of the pans, e.g. ripping, is unlikely to improve drainage and effective soil depth in the long term, because the disturbed zones are expected to be re-sealed by packed particles or by the aluminium-organic complex cement.

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