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Spatially and financially explicit population viability analysis of Maculinea alcon in The Netherlands.

Radchuk V, Wallisdevries MF, Schtickzelle N - PLoS ONE (2012)

Bottom Line: The PVA model was validated by the close match between its predictions and independent field observations on the patch occupancy pattern.Our results underline the importance of spatial and regional aspects (dispersal and connectivity) in determining the impact of conservation actions, even for a species previously considered as sedentary.They also illustrate that failure to account for the cost of management scenarios can lead to very different conclusions.

View Article: PubMed Central - PubMed

Affiliation: Biodiversity Research Centre, Earth & Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium. viktoriia.radchuk@uclouvain.be

ABSTRACT

Background: The conservation of species structured in metapopulations involves an important dilemma of resource allocation: should investments be directed at restoring/enlarging habitat patches or increasing connectivity. This is still an open question for Maculinea species despite they are among the best studied and emblematic butterfly species, because none of the population dynamics models developed so far included dispersal.

Methodology/principal findings: We developed the first spatially and financially explicit Population Viability Analysis model for Maculinea alcon, using field data from The Netherlands. Implemented using the RAMAS/GIS platform, the model incorporated both local (contest density dependence, environmental and demographic stochasticities), and regional population dynamics (dispersal rates between habitat patches). We selected four habitat patch networks, contrasting in several basic features (number of habitat patches, their quality, connectivity, and occupancy rate) to test how these features are affecting the ability to enhance population viability of four basic management options, designed to incur the same costs: habitat enlargement, habitat quality improvement, creation of new stepping stone habitat patches, and reintroduction of captive-reared butterflies. The PVA model was validated by the close match between its predictions and independent field observations on the patch occupancy pattern. The four patch networks differed in their sensitivity to model parameters, as well as in the ranking of management options. Overall, the best cost-effective option was enlargement of existing habitat patches, followed by either habitat quality improvement or creation of stepping stones depending on the network features. Reintroduction was predicted to generally be inefficient, except in one specific patch network.

Conclusions/significance: Our results underline the importance of spatial and regional aspects (dispersal and connectivity) in determining the impact of conservation actions, even for a species previously considered as sedentary. They also illustrate that failure to account for the cost of management scenarios can lead to very different conclusions.

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Related in: MedlinePlus

The four habitat patch networks differed in total area and quality of habitat patches.For each network the total area of the patches in each habitat quality category (low, moderate, average, fair and high) is shown.
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pone-0038684-g002: The four habitat patch networks differed in total area and quality of habitat patches.For each network the total area of the patches in each habitat quality category (low, moderate, average, fair and high) is shown.

Mentions: Our study system is located in Drenthe-Friesland region, in the Northern part of The Netherlands (Fig. 1). The regional habitat network consists of 96 heathland patches with areas ranging from 0.005 ha to 7.5 ha (25th percentile = 0.023 ha, median = 0.1 ha and 75th percentile = 0.5 ha) and between-patch distances ranging from 282 m to 75 km. Within the region, we selected as targets for conservation measures four patch networks, differing in basic features such as number of habitat patches, their quality, connectivity, and occupancy rate (Table 1, Fig. 2).


Spatially and financially explicit population viability analysis of Maculinea alcon in The Netherlands.

Radchuk V, Wallisdevries MF, Schtickzelle N - PLoS ONE (2012)

The four habitat patch networks differed in total area and quality of habitat patches.For each network the total area of the patches in each habitat quality category (low, moderate, average, fair and high) is shown.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3375285&req=5

pone-0038684-g002: The four habitat patch networks differed in total area and quality of habitat patches.For each network the total area of the patches in each habitat quality category (low, moderate, average, fair and high) is shown.
Mentions: Our study system is located in Drenthe-Friesland region, in the Northern part of The Netherlands (Fig. 1). The regional habitat network consists of 96 heathland patches with areas ranging from 0.005 ha to 7.5 ha (25th percentile = 0.023 ha, median = 0.1 ha and 75th percentile = 0.5 ha) and between-patch distances ranging from 282 m to 75 km. Within the region, we selected as targets for conservation measures four patch networks, differing in basic features such as number of habitat patches, their quality, connectivity, and occupancy rate (Table 1, Fig. 2).

Bottom Line: The PVA model was validated by the close match between its predictions and independent field observations on the patch occupancy pattern.Our results underline the importance of spatial and regional aspects (dispersal and connectivity) in determining the impact of conservation actions, even for a species previously considered as sedentary.They also illustrate that failure to account for the cost of management scenarios can lead to very different conclusions.

View Article: PubMed Central - PubMed

Affiliation: Biodiversity Research Centre, Earth & Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium. viktoriia.radchuk@uclouvain.be

ABSTRACT

Background: The conservation of species structured in metapopulations involves an important dilemma of resource allocation: should investments be directed at restoring/enlarging habitat patches or increasing connectivity. This is still an open question for Maculinea species despite they are among the best studied and emblematic butterfly species, because none of the population dynamics models developed so far included dispersal.

Methodology/principal findings: We developed the first spatially and financially explicit Population Viability Analysis model for Maculinea alcon, using field data from The Netherlands. Implemented using the RAMAS/GIS platform, the model incorporated both local (contest density dependence, environmental and demographic stochasticities), and regional population dynamics (dispersal rates between habitat patches). We selected four habitat patch networks, contrasting in several basic features (number of habitat patches, their quality, connectivity, and occupancy rate) to test how these features are affecting the ability to enhance population viability of four basic management options, designed to incur the same costs: habitat enlargement, habitat quality improvement, creation of new stepping stone habitat patches, and reintroduction of captive-reared butterflies. The PVA model was validated by the close match between its predictions and independent field observations on the patch occupancy pattern. The four patch networks differed in their sensitivity to model parameters, as well as in the ranking of management options. Overall, the best cost-effective option was enlargement of existing habitat patches, followed by either habitat quality improvement or creation of stepping stones depending on the network features. Reintroduction was predicted to generally be inefficient, except in one specific patch network.

Conclusions/significance: Our results underline the importance of spatial and regional aspects (dispersal and connectivity) in determining the impact of conservation actions, even for a species previously considered as sedentary. They also illustrate that failure to account for the cost of management scenarios can lead to very different conclusions.

Show MeSH
Related in: MedlinePlus