TY  - JOUR
A1  - Kürschner, Tobias
A1  - Scherer, Cédric
A1  - Radchuk, Viktoriia
A1  - Blaum, Niels
A1  - Kramer-Schadt, Stephanie
T1  - Movement can mediate temporal mismatches between resource availability and biological events in host-pathogen interactions
JF  - Ecology and evolution
N2  - Global change is shifting the timing of biological events, leading to temporal mismatches between biological events and resource availability. These temporal mismatches can threaten species' populations. Importantly, temporal mismatches not only exert strong pressures on the population dynamics of the focal species, but can also lead to substantial changes in pairwise species interactions such as host-pathogen systems. We adapted an established individual-based model of host-pathogen dynamics. The model describes a viral agent in a social host, while accounting for the host's explicit movement decisions. We aimed to investigate how temporal mismatches between seasonal resource availability and host life-history events affect host-pathogen coexistence, that is, disease persistence. Seasonal resource fluctuations only increased coexistence probability when in synchrony with the hosts' biological events. However, a temporal mismatch reduced host-pathogen coexistence, but only marginally. In tandem with an increasing temporal mismatch, our model showed a shift in the spatial distribution of infected hosts. It shifted from an even distribution under synchronous conditions toward the formation of disease hotspots, when host life history and resource availability mismatched completely. The spatial restriction of infected hosts to small hotspots in the landscape initially suggested a lower coexistence probability due to the critical loss of susceptible host individuals within those hotspots. However, the surrounding landscape facilitated demographic rescue through habitat-dependent movement. Our work demonstrates that the negative effects of temporal mismatches between host resource availability and host life history on host-pathogen coexistence can be reduced through the formation of temporary disease hotspots and host movement decisions, with implications for disease management under disturbances and global change.
KW  - classical swine fever
KW  - dynamic landscapes
KW  - global change
KW  - host– pathogen dynamics
KW  - individual‐ based model
KW  - movement ecology
Y1  - 2021
U6  - https://doi.org/10.1002/ece3.7478
SN  - 2045-7758
VL  - 11
IS  - 10
SP  - 5728
EP  - 5741
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - GEN
A1  - Horn, Juliane
A1  - Becher, Matthias A.
A1  - Johst, Karin
A1  - Kennedy, Peter J.
A1  - Osborne, Juliet L.
A1  - Radchuk, Viktoriia
A1  - Grimm, Volker
T1  - Honey bee colony performance affected by crop diversity and farmland structure
BT  - a modeling framework
T2  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - 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 using 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,P(H)andP(P,)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,P(H)andP(P)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 yr, andP(H)(269.5 kg) andP(P)(108 kg) being above viability thresholds for 5 yr. 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.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1351 
KW  - apis mellifera
KW  - BEEHAVE
KW  - colony viability
KW  - crop diversity
KW  - cropping system
KW  - decline
KW  - forage availability
KW  - forage gaps
KW  - honey bees
KW  - landscape generator
KW  - modeling
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-556943
SN  - 1866-8372
IS  - 1
ER  - 
TY  - JOUR
A1  - Horn, Juliane
A1  - Becher, Matthias A.
A1  - Johst, Karin
A1  - Kennedy, Peter J.
A1  - Osborne, Juliet L.
A1  - Radchuk, Viktoriia
A1  - Grimm, Volker
T1  - Honey bee colony performance affected by crop diversity and farmland structure
BT  - a modeling framework
JF  - Ecological applications
N2  - 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 using 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,P(H)andP(P,)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,P(H)andP(P)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 yr, andP(H)(269.5 kg) andP(P)(108 kg) being above viability thresholds for 5 yr. 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.
KW  - apis mellifera
KW  - BEEHAVE
KW  - colony viability
KW  - crop diversity
KW  - cropping system
KW  - decline
KW  - forage availability
KW  - forage gaps
KW  - honey bees
KW  - landscape generator
KW  - modeling
Y1  - 2020
U6  - https://doi.org/10.1002/eap.2216
SN  - 1939-5582
SN  - 1051-0761
VL  - 31
IS  - 1
SP  - 1
EP  - 22
PB  - Wiley Periodicals LLC
CY  - Washington DC
ER  - 
TY  - JOUR
A1  - Radchuk, Viktoriia
A1  - De Laender, Frederik
A1  - Cabral, Juliano Sarmento
A1  - Boulangeat, Isabelle
A1  - Crawford, Michael Scott
A1  - Bohn, Friedrich
A1  - De Raedt, Jonathan
A1  - Scherer, Cedric
A1  - Svenning, Jens-Christian
A1  - Thonicke, Kirsten
A1  - Schurr, Frank M.
A1  - Grimm, Volker
A1  - Kramer-Schadt, Stephanie
T1  - The dimensionality of stability depends on disturbance type
JF  - Ecology letters
N2  - Ecosystems respond in various ways to disturbances. Quantifying ecological stability therefore requires inspecting multiple stability properties, such as resistance, recovery, persistence and invariability. Correlations among these properties can reduce the dimensionality of stability, simplifying the study of environmental effects on ecosystems. A key question is how the kind of disturbance affects these correlations. We here investigated the effect of three disturbance types (random, species-specific, local) applied at four intensity levels, on the dimensionality of stability at the population and community level. We used previously parameterized models that represent five natural communities, varying in species richness and the number of trophic levels. We found that disturbance type but not intensity affected the dimensionality of stability and only at the population level. The dimensionality of stability also varied greatly among species and communities. Therefore, studying stability cannot be simplified to using a single metric and multi-dimensional assessments are still to be recommended.
KW  - Community model
KW  - disturbance intensity
KW  - disturbance type
KW  - extinction
KW  - individual-based model
KW  - invariability
KW  - persistence
KW  - recovery
KW  - resistance
Y1  - 2019
U6  - https://doi.org/10.1111/ele.13226
SN  - 1461-023X
SN  - 1461-0248
VL  - 22
IS  - 4
SP  - 674
EP  - 684
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - GEN
A1  - Radchuk, Viktoriia
A1  - Kramer-Schadt, Stephanie
A1  - Grimm, Volker
T1  - Transferability of mechanistic ecological models is about emergence
T2  - Trends in ecology and evolution
Y1  - 2019
U6  - https://doi.org/10.1016/j.tree.2019.01.010
SN  - 0169-5347
SN  - 1872-8383
VL  - 34
IS  - 6
SP  - 487
EP  - 488
PB  - Elsevier
CY  - London
ER  - 
TY  - JOUR
A1  - Radchuk, Viktoriia
A1  - Reed, Thomas
A1  - Teplitsky, Celine
A1  - van de Pol, Martijn
A1  - Charmantier, Anne
A1  - Hassall, Christopher
A1  - Adamik, Peter
A1  - Adriaensen, Frank
A1  - Ahola, Markus P.
A1  - Arcese, Peter
A1  - Miguel Aviles, Jesus
A1  - Balbontin, Javier
A1  - Berg, Karl S.
A1  - Borras, Antoni
A1  - Burthe, Sarah
A1  - Clobert, Jean
A1  - Dehnhard, Nina
A1  - de Lope, Florentino
A1  - Dhondt, Andre A.
A1  - Dingemanse, Niels J.
A1  - Doi, Hideyuki
A1  - Eeva, Tapio
A1  - Fickel, Jörns
A1  - Filella, Iolanda
A1  - Fossoy, Frode
A1  - Goodenough, Anne E.
A1  - Hall, Stephen J. G.
A1  - Hansson, Bengt
A1  - Harris, Michael
A1  - Hasselquist, Dennis
A1  - Hickler, Thomas
A1  - Jasmin Radha, Jasmin
A1  - Kharouba, Heather
A1  - Gabriel Martinez, Juan
A1  - Mihoub, Jean-Baptiste
A1  - Mills, James A.
A1  - Molina-Morales, Mercedes
A1  - Moksnes, Arne
A1  - Ozgul, Arpat
A1  - Parejo, Deseada
A1  - Pilard, Philippe
A1  - Poisbleau, Maud
A1  - Rousset, Francois
A1  - Rödel, Mark-Oliver
A1  - Scott, David
A1  - Carlos Senar, Juan
A1  - Stefanescu, Constanti
A1  - Stokke, Bard G.
A1  - Kusano, Tamotsu
A1  - Tarka, Maja
A1  - Tarwater, Corey E.
A1  - Thonicke, Kirsten
A1  - Thorley, Jack
A1  - Wilting, Andreas
A1  - Tryjanowski, Piotr
A1  - Merila, Juha
A1  - Sheldon, Ben C.
A1  - Moller, Anders Pape
A1  - Matthysen, Erik
A1  - Janzen, Fredric
A1  - Dobson, F. Stephen
A1  - Visser, Marcel E.
A1  - Beissinger, Steven R.
A1  - Courtiol, Alexandre
A1  - Kramer-Schadt, Stephanie
T1  - Adaptive responses of animals to climate change are most likely insufficient
JF  - Nature Communications
N2  - Biological responses to climate change have been widely documented across taxa and regions, but it remains unclear whether species are maintaining a good match between phenotype and environment, i.e. whether observed trait changes are adaptive. Here we reviewed 10,090 abstracts and extracted data from 71 studies reported in 58 relevant publications, to assess quantitatively whether phenotypic trait changes associated with climate change are adaptive in animals. A meta-analysis focussing on birds, the taxon best represented in our dataset, suggests that global warming has not systematically affected morphological traits, but has advanced phenological traits. We demonstrate that these advances are adaptive for some species, but imperfect as evidenced by the observed consistent selection for earlier timing. Application of a theoretical model indicates that the evolutionary load imposed by incomplete adaptive responses to ongoing climate change may already be threatening the persistence of species.
Y1  - 2019
U6  - https://doi.org/10.1038/s41467-019-10924-4
SN  - 2041-1723
VL  - 10
PB  - Nature Publ. Group
CY  - London
ER  - 
TY  - JOUR
A1  - Radchuk, Viktoriia
A1  - Kramer-Schadt, Stephanie
A1  - Fickel, Jörns
A1  - Wilting, Andreas
T1  - Distributions of mammals in Southeast Asia: The role of the legacy of climate and species body mass
JF  - Journal of biogeography
N2  - Aim Current species distributions are shaped by present and past biotic and abiotic factors. Here, we assessed whether abiotic factors (habitat availability) in combination with past connectivity and a biotic factor (body mass) can explain the unique distribution pattern of Southeast Asian mammals, which are separated by the enigmatic biogeographic transition zone, the Isthmus of Kra (IoK), for which no strong geophysical barrier exists. Location Southeast Asia. Taxon Mammals. Methods We projected habitat suitability for 125 mammal species using climate data for the present period and for two historic periods: mid-Holocene (6 ka) and last glacial maximum (LGM 21 ka). Next, we employed a phylogenetic linear model to assess how present species distributions were affected by the suitability of areas in these different periods, habitat connectivity during LGM and species body mass. Results Our results show that cooler climate during LGM provided suitable habitat south of IoK for species presently distributed north of IoK (in mainland Indochina). However, the potentially suitable habitat for these Indochinese species did not stretch very far southwards onto the exposed Sunda Shelf. Instead, we found that the emerged landmasses connecting Borneo and Sumatra provided suitable habitat for forest dependent Sundaic species. We show that for species whose current distribution ranges are mainly located in Indochina, the area of the distribution range that is located south of IoK is explained by the suitability of habitat in the past and present in combination with the species body mass. Main conclusions We demonstrate that a strong geophysical barrier may not be necessary for maintaining a biogeographic transition zone for mammals, but that instead a combination of abiotic and biotic factors may suffice.
KW  - habitat suitability
KW  - Isthmus of Kra
KW  - least-cost path
KW  - PanTHERIA
KW  - phylogenetic regression
KW  - species distribution model
Y1  - 2019
U6  - https://doi.org/10.1111/jbi.13675
SN  - 0305-0270
SN  - 1365-2699
VL  - 46
IS  - 10
SP  - 2350
EP  - 2362
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Scherer, Cedric
A1  - Radchuk, Viktoriia
A1  - Staubach, Christoph
A1  - Mueller, Sophie
A1  - Blaum, Niels
A1  - Thulke, Hans-Hermann
A1  - Kramer-Schadt, Stephanie
T1  - Seasonal host life-history processes fuel disease dynamics at different spatial scales
JF  - Journal of animal ecology : a journal of the British Ecological Society
N2  - Understanding the drivers underlying disease dynamics is still a major challenge in disease ecology, especially in the case of long-term disease persistence. Even though there is a strong consensus that density-dependent factors play an important role for the spread of diseases, the main drivers are still discussed and, more importantly, might differ between invasion and persistence periods. Here, we analysed long-term outbreak data of classical swine fever, an important disease in both wild boar and livestock, prevalent in the wild boar population from 1993 to 2000 in Mecklenburg-Vorpommern, Germany. We report outbreak characteristics and results from generalized linear mixed models to reveal what factors affected infection risk on both the landscape and the individual level. Spatiotemporal outbreak dynamics showed an initial wave-like spread with high incidence during the invasion period followed by a drop of incidence and an increase in seroprevalence during the persistence period. Velocity of spread increased with time during the first year of outbreak and decreased linearly afterwards, being on average 7.6 km per quarter. Landscape- and individual-level analyses of infection risk indicate contrasting seasonal patterns. During the persistence period, infection risk on the landscape level was highest during autumn and winter seasons, probably related to spatial behaviour such as increased long-distance movements and contacts induced by rutting and escaping movements. In contrast, individual-level infection risk peaked in spring, probably related to the concurrent birth season leading to higher densities, and was significantly higher in piglets than in reproductive animals. Our findings highlight that it is important to investigate both individual- and landscape-level patterns of infection risk to understand long-term persistence of wildlife diseases and to guide respective management actions. Furthermore, we highlight that exploring different temporal aggregation of the data helps to reveal important seasonal patterns, which might be masked otherwise.
KW  - classical swine fever
KW  - disease invasion
KW  - infection risk
KW  - pathogen persistence
KW  - seasonality
KW  - Sus scrofa
KW  - wild boar
KW  - wildlife disease
Y1  - 2019
U6  - https://doi.org/10.1111/1365-2656.13070
SN  - 0021-8790
SN  - 1365-2656
VL  - 88
IS  - 11
SP  - 1812
EP  - 1824
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Radchuk, Viktoriia
A1  - Oppel, Steffen
A1  - Groeneveld, Juergen
A1  - Grimm, Volker
A1  - Schtickzelle, Nicolas
T1  - Simple or complex: Relative impact of data availability and model purpose on the choice of model types for population viability analyses
JF  - Ecological modelling : international journal on ecological modelling and engineering and systems ecolog
N2  - Population viability analysis (PVA) models are used to estimate population extinction risk under different scenarios. Both simple and complex PVA models are developed and have their specific pros and cons; the question therefore arises whether we always use the most appropriate model type. Generally, the specific purpose of a model and the availability of data are listed as determining the choice of model type, but this has not been formally tested yet. We quantified the relative importance of model purpose and nine metrics of data availability and resolution for the choice of a PVA model type, while controlling for effects of the different life histories of the modelled species. We evaluated 37 model pairs: each consisting of a generally simpler, population-based model (PBM) and a more complex, individual-based model (IBM) developed for the same species. The choice of model type was primarily affected by the availability and resolution of demographic, dispersal and spatial data. Low-resolution data resulted in the development of less complex models. Model purpose did not affect the choice of the model type. We confirm the general assumption that poor data availability is the main reason for the wide use of simpler models, which may have limited predictive power for population responses to changing environmental conditions. Conservation biology is a crisis discipline where researchers learned to work with the data at hand. However, for threatened and poorly-known species, there is no short-cut when developing either a PBM or an IBM: investments to collect appropriately detailed data are required to ensure PVA models can assess extinction risk under complex environmental conditions. (C) 2015 Elsevier B.V. All rights reserved.
KW  - Model complexity
KW  - Individual-based model
KW  - Population-based model
KW  - Matrix model
KW  - Structured population model
KW  - Stage-based model
Y1  - 2016
U6  - https://doi.org/10.1016/j.ecolmodel.2015.11.022
SN  - 0304-3800
SN  - 1872-7026
VL  - 323
SP  - 87
EP  - 95
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Patel, Riddhi P.
A1  - Förster, Daniel W.
A1  - Kitchener, Andrew C.
A1  - Rayan, Mark D.
A1  - Mohamed, Shariff W.
A1  - Werner, Laura
A1  - Lenz, Dorina
A1  - Pfestorf, Hans
A1  - Kramer-Schadt, Stephanie
A1  - Radchuk, Viktoriia
A1  - Fickel, Jörns
A1  - Wilting, Andreas
T1  - Two species of Southeast Asian cats in the genus Catopuma with diverging histories: an island endemic forest specialist and a widespread habitat generalist
JF  - Royal Society Open Science
N2  - Background. The bay cat Catopuma badia is endemic to Borneo, whereas its sister species the Asian golden cat Catopuma temminckii is distributed from the Himalayas and southern China through Indochina, Peninsular Malaysia and Sumatra. Based onmorphological data, up to five subspecies of the Asian golden cat have been recognized, but a taxonomic assessment, including molecular data and morphological characters, is still lacking. Results. We combined molecular data (whole mitochondrial genomes), morphological data (pelage) and species distribution projections (up to the Late Pleistocene) to infer how environmental changes may have influenced the distribution of these sister species over the past 120 000 years. The molecular analysis was based on sequenced mitogenomes of 3 bay cats and 40 Asian golden cats derived mainly from archival samples. Our molecular data suggested a time of split between the two species approximately 3.16 Ma and revealed very low nucleotide diversity within the Asian golden cat population, which supports recent expansion of the population. Discussion. The low nucleotide diversity suggested a population bottleneck in the Asian golden cat, possibly caused by the eruption of the Toba volcano in Northern Sumatra (approx. 74 kya), followed by a continuous population expansion in the Late Pleistocene/Early Holocene. Species distribution projections, the reconstruction of the demographic history, a genetic isolation-by-distance pattern and a gradual variation of pelage pattern support the hypothesis of a post-Toba population expansion of the Asian golden cat from south China/Indochina to PeninsularMalaysia and Sumatra. Our findings reject the current classification of five subspecies for the Asian golden cat, but instead support either a monotypic species or one comprising two subspecies: (i) the Sunda golden cat, distributed south of the Isthmus of Kra: C. t. temminckii and (ii) Indochinese, Indian, Himalayan and Chinese golden cats, occurring north of the Isthmus: C. t. moormensis.
KW  - Felidae
KW  - Southeast Asia
KW  - last glacial maximum
KW  - Toba volcanic eruption
KW  - hybrid capture
KW  - next generation sequencing
Y1  - 2016
U6  - https://doi.org/10.1098/rsos.160350
SN  - 2054-5703
VL  - 3
SP  - 741
EP  - 752
PB  - Royal Society
CY  - London
ER  -