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Spatially and Financially Explicit Population Viability Analysis of Maculinea alcon in The Netherlands

Viktoriia Radchuk, Michiel F. WallisDeVries, Nicolas Schtickzelle, Bengt Hansson
2012 PLoS ONE  
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
more » ... y 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.
doi:10.1371/journal.pone.0038684 pmid:22719922 pmcid:PMC3375285 fatcat:txarbrba75e3nl6hbws5ibxuam

Honeybee colony performance affected by crop diversity and farmland structure: a modelling framework [article]

Juliane Horn, Matthias A. Becher, Karin Johst, Peter J. Kennedy, Juliet L. Osborne, Viktoriia Radchuk, Volker Grimm
2019 bioRxiv   pre-print
Forage availability has been suggested as one driver of the observed decline in honeybees. However, little is known about the effects of its spatiotemporal variation on colony success. We present a modelling framework for assessing honeybee colony viability in cropping systems. Based on two real farmland structures, we developed a landscape generator to design cropping systems varying in crop species identity, diversity, and relative abundance. The landscape scenarios generated were evaluated
more » ... ing the existing honeybee colony model BEEHAVE, which links foraging to in-hive dynamics. We thereby explored how different cropping systems determine spatiotemporal forage availability and, in turn, honeybee colony viability (e.g., time to extinction, TTE) and resilience (indicated by, e.g. brood mortality). To assess overall colony viability, we developed metrics, PH and PP, which quantified how much nectar and pollen provided by a cropping system per year was converted into a colony's adult worker population. Both crop species identity and diversity determined the temporal continuity in nectar and pollen supply and thus colony viability. Overall farmland structure and relative crop abundance were less important, but details mattered. For monocultures and for four-crop species systems composed of cereals, oilseed rape, maize and sunflower, PH and PP were below the viability threshold. Such cropping systems showed frequent, badly timed, and prolonged forage gaps leading to detrimental cascading effects on life stages and in-hive work force, which critically reduced colony resilience. Four-crop systems composed of rye-grass-dandelion pasture, trefoil-grass pasture, sunflower and phacelia ensured continuous nectar and pollen supply resulting in TTE > 5 years, and PH (269.5 kg) and PP (108 kg) being above viability thresholds for five years. Overall, trefoil-grass pasture, oilseed rape, buckwheat and phacelia improved the temporal continuity in forage supply and colony's viability. Our results are hypothetical as they are obtained from simplified landscape settings, but they nevertheless match empirical observations, in particular the viability threshold. Our framework can be used to assess the effects of cropping systems on honeybee viability and to develop land-use strategies that help maintain pollination services by avoiding prolonged and badly timed forage gaps.
doi:10.1101/2019.12.17.880054 fatcat:7rmy7b3iezf63ks5pwpguveoka

Moving infections: individual movement decisions drive disease persistence in spatially structured landscapes

Cédric Scherer, Viktoriia Radchuk, Mathias Franz, Hans–Hermann Thulke, Martin Lange, Volker Grimm, Stephanie Kramer–Schadt
2020 Oikos  
A major advantage is their mechanistic nature from which higher-level processes emerge Railsback 2005, Radchuk et al. 2019a, b) .  ...  In addition, seasonal or unpredictable short-term disturbances may influence the dynamics of the host population (Radchuk et al. 2019b) .  ... 
doi:10.1111/oik.07002 fatcat:oqzf6u4qxvdp5cwjufe5ofwvum

From individuals to population cycles: the role of extrinsic and intrinsic factors in rodent populations

Viktoriia Radchuk, Rolf A. Ims, Harry P. Andreassen
2016 Ecology  
Rodent population cycles have fascinated scientists for a long time. Among various hypotheses, an interaction of an extrinsic factor (predation) with intrinsic factors (e.g., sociality and dispersal) was suggested to lead to the generation of population cycles. Here, we tested this hypothesis with an individual-based model fully parameterized with an exceptionally rich empirical database on vole life histories. We employed a full factorial design that included models with the following factors:
more » ... predation only, predation and sociality, predation and dispersal, and predation and both sociality and dispersal. A comprehensive set of metrics was used to compare results of these four models with the longterm population dynamics of natural vole populations. Only the full model, which included both intrinsic factors and predation, yielded cycle periods, amplitudes, and autumn population sizes closest to those observed in nature. Our approach allows to model, as emergent properties of individual life histories, the sort of nonlinear density-and phase-dependence that is expected to destabilize population dynamics. We suggest that the individual-based approach is useful for addressing the effects of other mechanisms on rodent populations that operate at finer temporal and spatial scales than have been explored with models so far.
doi:10.1890/15-0756.1 pmid:27197398 fatcat:mbso4lbn7jh4robbxi332kzify

Biodiversity and ecosystem functioning decoupled: invariant ecosystem functioning despite non-random reductions in consumer diversity

Viktoriia Radchuk, Frederik De Laender, Paul J. Van den Brink, Volker Grimm
2015 Oikos  
doi:10.1111/oik.02220 fatcat:raxhonghm5f67hnvrohfinoyie

Arthropod abundance modulates bird community responses to urbanization

Aimara Planillo, Stephanie Kramer‐Schadt, Sascha Buchholz, Pierre Gras, Moritz von der Lippe, Viktoriia Radchuk
2020 Diversity and Distributions: A journal of biological invasions and biodiversity  
Stephanie Kramer-Schadt https://orcid. org/0000-0002-9269-4446 B I OS K E TCH Viktoriia Radchuk https://orcid.org/0000-0003-3072-0095 R E FE R E N C E S ( Berlin Environmental Atlas, 2018).  ... 
doi:10.1111/ddi.13169 fatcat:iacixsapgjgx5cxwspxouxcipq

Honey bee colony performance affected by crop diversity and farmland structure: a modeling framework

Juliane Horn, Matthias A Becher, Karin Johst, Peter J Kennedy, Juliet L Osborne, Viktoriia Radchuk, Volker Grimm
2020 Ecological Applications  
Forage availability has been suggested as one driver of the observed decline in honey bees. However, little is known about the effects of its spatiotemporal variation on colony success. We present a modeling framework for assessing honey bee colony viability in cropping systems. Based on two real farmland structures, we developed a landscape generator to design cropping systems varying in crop species identity, diversity, and relative abundance. The landscape scenarios generated were evaluated
more » ... sing the existing honey bee colony model BEEHAVE, which links foraging to in-hive dynamics. We thereby explored how different cropping systems determine spatiotemporal forage availability and, in turn, honey bee colony viability (e.g., time to extinction, TTE) and resilience (indicated by, e.g. brood mortality). To assess overall colony viability, we developed metrics, PH and PP, which quantified how much nectar and pollen provided by a cropping system per year was converted into a colony's adult worker population. Both crop species identity and diversity determined the temporal continuity in nectar and pollen supply and thus colony viability. Overall farmland structure and relative crop abundance were less important, but details mattered. For monocultures and for four-crop species systems composed of cereals, oilseed rape, maize and sunflower, PH and PP were below the viability threshold. Such cropping systems showed frequent, badly timed, and prolonged forage gaps leading to detrimental cascading effects on life stages and in-hive work force, which critically reduced colony resilience. Four-crop systems composed of rye-grass-dandelion pasture, trefoil-grass pasture, sunflower and phacelia ensured continuous nectar and pollen supply resulting in TTE > 5 years, and PH (269.5 kg) and PP (108 kg) being above viability thresholds for five years. Overall, trefoil-grass pasture, oilseed rape, buckwheat and phacelia improved the temporal continuity in forage supply and colony's viability. Our results are hypothetical as they are obtained from simplified landscape settings, but they nevertheless match empirical observations, in particular the viability threshold. Our framework can be used to assess the effects of cropping systems on honey bee viability and to develop land-use strategies that help maintain pollination services by avoiding prolonged and badly timed forage gaps.
doi:10.1002/eap.2216 pmid:32810342 fatcat:h4y55bywobgxxcqdehl5mtyafm

Distributions of mammals in Southeast Asia: The role of the legacy of climate and species body mass

Viktoriia Radchuk, Stephanie Kramer‐Schadt, Joerns Fickel, Andreas Wilting
2019 Journal of Biogeography  
Radchuk https://orcid.org/0000-0003-3072-0095 Table 2 ) 2 .  ...  Distributions of mammals in Southeast Asia: the role of the legacy of climate and species body mass DOI: doi:10.5061/dryad.qp44619 Journal: Journal of Biogeography Journal manuscript number: JBI-18-0547 O RCI D Viktoriia  ... 
doi:10.1111/jbi.13675 fatcat:uinf3ws5ircb5nmecpzotvsvqy

Halfway to self-sustainability: Reintroduced migratory European Northern Bald Ibises (Geronticus eremita) still need management interventions for population viability [article]

Sinah Drenske, Viktoriia Radchuk, Cédric Scherer, Corinna Esterer, Ingo Kowarik, Johannes Fritz, Stephanie Kramer-Schadt
2021 bioRxiv   pre-print
Northern Bald Ibis (NBI) have disappeared from Europe already in Middle Age. Since 2003 a migratory population is reintroduced in Central Europe. We conducted demographic analyses of survival and reproduction of 384 NBI over a period of 12 years (2008-2019). These data also formed the basis for a population viability analysis (PVA) simulating the possible future development of the NBI population in different scenarios. We tested life-stage specific survival rates for differences between these
more » ... ages, raising types and colonies as well as the influence of stochastic events and NBI supplements on the population growth. Stage specific survival rates ranged from 0.64 to 0.78. 61% of the mature females reproduce with a mean fecundity of 2.15 fledglings per nest. The complementary PVA indicated that the release population is close to self-sustainability with a given lambda 0.95 and 24% extinction probability within 50 years. Of the 326 future scenarios tested, 94 % reached the criteria of <5% extinction probability and population growth rates >1. In case of positive population growth, stochastic events had a limited effect. Of 820 sub-scenarios with different stochastic event frequencies and severities 87 % show population growth despite the occurrence of stochastic events. Predictions can be made based on the results of the individual-based model as to whether and under what circumstances the reintroduced NBI population can survive. This study shows that a PVA can support reintroduction success that should work closely together with the project in the field for mutual benefit, to optimize future management decisions.
doi:10.1101/2021.04.03.438331 fatcat:hpur6mxsn5fihoyargckfgnemq

Identifying refuges for Borneo's elusive Hose's civet

John Mathai, Jürgen Niedballa, Viktoriia Radchuk, Rahel Sollmann, Ilja Heckmann, Jedediah Brodie, Matthew Struebig, Andrew J. Hearn, Joanna Ross, David W. Macdonald, Jason Hon, Andreas Wilting
2019 Global Ecology and Conservation  
Human-induced environmental changes, particularly climate change, pose a threat to many tropical montane species, making the identification of optimal future habitat a conservation priority. Here we used maximum entropy (Maxent) and boosted regression trees to predict suitable habitat of the threatened Bornean highland endemic Hose's civet (Diplogale hosei), that is currently available, and for future time periods (2050s and 2080s), considering future land cover and climate change predictions.
more » ... ext, we identified areas that were consistently suitable under current and future model predictions as forest refuges. Our analysis predicted that Hose's civet is restricted mainly to the highlands of Borneo to an area less than 20,000 km 2 (about 2% of the entire island of Borneo). Changes in land cover have little impact on predicted suitable area for the species. However, we predicted habitat loss due to climate change to approximate 86% by 2080, except under a "green economy scenario" which showed stable or increasing suitable habitat. Refuges were small, about 11% of 2010 habitat, and mostly restricted to lower montane forest. About 28e35% of refuges lie within the current protected area network though much is designated as commercial forests within the proposed Heart of Borneo (HoB). For the conservation of Hose's civet and likely other Bornean highland endemics, we recommend increased wildlife and forest law enforcement in identified protected refuges and sustainable timber harvesting practices in surrounding commercial forests, both within the HoB and the extensions we identified. Results of our green model showed that efforts to reduce greenhouse gas emissions will likely contribute immensely to the long-term conservation of highland species such as Hose's civet.
doi:10.1016/j.gecco.2019.e00531 fatcat:p3ksasuujrasncskln73eunv2q

Movement can mediate temporal mismatches between resource availability and biological events in host–pathogen interactions

Tobias Kürschner, Cédric Scherer, Viktoriia Radchuk, Niels Blaum, Stephanie Kramer‐Schadt
2021 Ecology and Evolution  
Viktoriia Radchuk: Formal analysis (equal); Writing-review & editing (equal). Niels Blaum: Writing-review & editing (equal).  ...  O RCI D Tobias Kürschner https://orcid.org/0000-0002-4587-9894 Cédric Scherer https://orcid.org/0000-0003-0465-2543 Viktoriia Radchuk https://orcid.org/0000-0003-3072-0095 dividual age-dependent courses  ... 
doi:10.1002/ece3.7478 pmid:34026043 pmcid:PMC8131764 fatcat:o636ebxr3jc23hku76zpplu4kq

Plant quality and local adaptation undermine relocation in a bog specialist butterfly

Camille Turlure, Viktoriia Radchuk, Michel Baguette, Mark Meijrink, Arnold van den Burg, Michiel Wallis De Vries, Gert-Jan van Duinen
2012 Ecology and Evolution  
Radchuk, pers. obs.) and manipulations of adults may influence their behavior at the release site, as has been observed for other species (Heidinger et al. 2009 ).  ... 
doi:10.1002/ece3.427 pmid:23467336 pmcid:PMC3586634 fatcat:gjoj2wwxcrd6ze5jm6dj4pt34i

Each life stage matters: the importance of assessing the response to climate change over the complete life cycle in butterflies

Viktoriia Radchuk, Camille Turlure, Nicolas Schtickzelle, Jonathan Newman
2012 Journal of Animal Ecology  
Radchuk, C. Turlure & N.  ...  Radchuk, C. Turlure & N. Schtickzelle Table 2.  ... 
doi:10.1111/j.1365-2656.2012.02029.x pmid:22924795 fatcat:rsolc5nznzdqlhkvpefliofvk4

Reintroducing Environmental Change Drivers in Biodiversity–Ecosystem Functioning Research

Frederik De Laender, Jason R. Rohr, Roman Ashauer, Donald J. Baird, Uta Berger, Nico Eisenhauer, Volker Grimm, Udo Hommen, Lorraine Maltby, Carlos J. Meliàn, Francesco Pomati, Ivo Roessink (+2 others)
2016 Trends in Ecology & Evolution  
39 For the past 20 years, research on biodiversity and ecosystem functioning (B-EF) has only 40 implicitly considered the underlying role of environmental change. We illustrate that 41 explicitly re-introducing environmental change drivers in B-EF research is needed to predict 42 the functioning of ecosystems facing changes in biodiversity. Next, we show how this re-43 introduction improves experimental control over community composition and structure, 44 which helps to obtain mechanistic
more » ... t about how multiple aspects of biodiversity relate to 45 function, and how biodiversity and function relate in food-webs. We also highlight 46 challenges for the proposed re-introduction, and suggest analyses and experiments to better 47
doi:10.1016/j.tree.2016.09.007 pmid:27742415 pmcid:PMC5118049 fatcat:tx7bnc3w7nh2tnm2epwmkrlbbm

Towards better modelling and decision support: Documenting model development, testing, and analysis using TRACE

Volker Grimm, Jacqueline Augusiak, Andreas Focks, Béatrice M. Frank, Faten Gabsi, Alice S.A. Johnston, Chun Liu, Benjamin T. Martin, Mattia Meli, Viktoriia Radchuk, Pernille Thorbek, Steven F. Railsback
2014 Ecological Modelling  
The potential of ecological models for supporting environmental decision making is increasingly acknowledged. However, it often remains unclear whether a model is realistic and reliable enough. Good practice for developing and testing ecological models has not yet been established. Therefore, TRACE, a general framework for documenting a model's rationale, design, and testing was recently suggested. Originally TRACE was aimed at documenting good modelling practice. However, the word
more » ... n' does not convey TRACE's urgency. Therefore, we re-define TRACE as a tool for planning, performing, and documenting good modelling practice. TRACE documents should provide convincing evidence that a model was thoughtfully designed, correctly implemented, thoroughly tested, well understood, and appropriately used for its intended purpose. TRACE documents link the science underlying a model to its application, thereby also linking modellers and model users, for example stakeholders, decision makers, and developers of policies. We report on first experiences in producing TRACE documents. We found that the original idea underlying TRACE was valid, but to make its use more coherent and efficient, an update of its structure and more specific guidance for its use are needed. The updated TRACE format follows the recently developed framework of model 'evaludation': the entire process of establishing model quality and credibility throughout all stages of model development, analysis, and application. TRACE thus becomes a tool for planning, documenting, and assessing model evaludation, which includes understanding the rationale behind a model and its envisaged use. We introduce the new structure and revised terminology of TRACE and provide examples.
doi:10.1016/j.ecolmodel.2014.01.018 fatcat:2z57b4dzrvf6lchhki2y7dodxu
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