DOCSLIB.ORG

Habitat-Quality Effects on Metapopulation Dynamics in Greater White-Toothed Shrews, Crocidura Russula

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Habitat-Quality Effects on Metapopulation Dynamics in Greater White-Toothed Shrews, Crocidura Russula Ecology, 89(10), 2008, pp. 2777–2785 Ó 2008 by the Ecological Society of America HABITAT-QUALITY EFFECTS ON METAPOPULATION DYNAMICS IN GREATER WHITE-TOOTHED SHREWS, CROCIDURA RUSSULA 1 J. JAQUIE´RY, J. GUE´LAT,T.BROQUET,L.BERSET-BRA¨NDLI,E.PELLEGRINI,R.MORESI,A.H.HIRZEL, AND N. PERRIN Department of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland Abstract. The effects of patch size and isolation on metapopulation dynamics have received wide empirical support and theoretical formalization. By contrast, the effects of patch quality seem largely underinvestigated, partly due to technical difficulties in properly assessing quality. Here we combine habitat-quality modeling with four years of demographic monitoring in a metapopulation of greater white-toothed shrews (Crocidura russula)to investigate the role of patch quality on metapopulation processes. Together, local patch quality and connectivity significantly enhanced local population sizes and occupancy rates (R2 ¼ 14% and 19%, respectively). Accounting for the quality of patches connected to the focal one and acting as potential sources improved slightly the model explanatory power for local population sizes, pointing to significant source–sink dynamics. Local habitat quality, in interaction with connectivity, also increased colonization rate (R2 ¼ 28%), suggesting the ability of immigrants to target high-quality patches. Overall, patterns were best explained when assuming a mean dispersal distance of 800 m, a realistic value for the species under study. Our results thus provide evidence that patch quality, in interaction with connectivity, may affect major demographic processes. Key words: colonization; connectivity; Crocidura russula; ecological-niche factor analysis (ENFA); extinction; greater white-toothed shrew; habitat suitability; metapopulation dynamics; occupancy; Valle´ede Joux, Switzerland. INTRODUCTION given landscape depends on the ‘‘capacity’’ of the The concept of metapopulation refers to a set of local metapopulation, a function of the sizes and positions demes (or patches) connected by some level of migration of its patches. The size of a patch (considered as a and undergoing disequilibrium dynamics characterized surrogate for local carrying capacity) affects its extinc- by local extinctions and recolonizations (Hanski and tion rate and contribution to the migrant pool, while its Gaggiotti 2004). One of the earliest attempts to isolation matters by affecting connectivity (i.e., contri- formalize these dynamics was Levins’s (1969) patch- bution to recolonization). occupancy island model. Assuming that all local demes Patch quality has rarely been explicitly considered in are equivalent in terms of extinction probability and this context and might be seen as the main missing connectivity, this model predicts expected occupancy parameter in current metapopulation modeling (e.g., rate as a function of extinction and colonization rates. Thomas et al. 2001). Habitat quality is indeed bound to These first inroads prompted research on different affect all processes determining metapopulation dynam- fronts. On the empirical side, subsequent investigations ics. On the one hand, high-quality patches may benefit have shown that Levins’s simplifying assumptions of from lower extinction rates (by enhancing individual homogeneous rates are often not tenable. Local demes survival or fecundity) or higher colonization rates (by differ in extinction rate and connectivity, which affects attracting immigrants or facilitating settlement). On the metapopulation dynamics (e.g., Verboom et al. 1991, other hand, they may send more migrants (owing to Kindvall and Ahlen 1992, Hanski and Thomas 1994, higher productivity), and thereby contribute more than Eber and Brandl 1996). On the theoretical side, attempts others to recolonization processes. Patch quality might were made to integrate these heterogeneities into thus also provide an excellent surrogate for local metapopulation modeling (e.g., Hanski 1994, Hastings carrying capacity. Although some studies have con- and Harrison 1994). Hanski and Ovaskainen (2000, firmed a role for habitat quality in occupancy, coloni- 2003, see also Ovaskainen and Hanski 2001, 2004) zation, or extinction patterns (e.g., Thomas et al. 2001, contributed significantly to the theory of stochastic Fleishman et al. 2002, Franken and Hik 2004), these patch occupancy models by allowing patches to differ in topics remain largely underinvestigated, presumably due size and connectivity. The condition for viability in a to practical difficulties in assessing habitat quality. Recent developments in habitat-quality modeling are now tracing new inroads into this area. Habitat-quality Manuscript received 1 November 2007; accepted 31 January 2008. Corresponding Editor: F. S. Dobson. modeling is emerging as a discipline of its own, building 1 E-mail: [email protected] on a set of spatially explicit tools (geographic informa- 2777 2778 J. JAQUIE´RY ET AL. Ecology, Vol. 89, No. 10 tion systems) and associated statistics to identify tored in summer (August to September) in 106 sites, of environmental variables affecting a species’ distribution which 62 were studied in 2003 and 84 in each of the years and assess local habitat suitability (reviewed in Guisan 2004, 2005, and 2006 (Fig. 1). Sampling sites consisted and Zimmermann 2000). Up to now, applications to of 20 3 20 m areas within private gardens. These were metapopulation studies have been mostly restricted to always adjacent to human habitations and usually the delineation of local patches (e.g., Akc¸akaya et al. comprised some lawn, a vegetable garden, a compost 1995, Akc¸akaya and Atwood 1997, Akc¸akaya 2000a, b). heap, a garden dwarf, wood piles, stone walls, and Efforts were made by Moilanen and Hanski (1998) to hedges. Forty-two of these sites were sampled over all formally integrate habitat modeling into a metapopula- four years, 40 sites over three consecutive years, two tion dynamics framework, but the predictive power of sites over two consecutive years, and 22 sites only once. these models was not improved beyond the effects of Individuals were livetrapped using 20 Longworth small- patch area and isolation. mammal traps (B. N. Bolton, Inc, Vernon, British In the present paper, we combine spatially explicit Columbia, Canada) per garden, baited with Tenebrio modeling with a four-year demographic study to molitor larvae. After a pre-baiting period of two to four investigate the role of habitat quality on metapopulation days, each site was visited four times during two dynamics in a small mammal, the greater white-toothed consecutive days. The traps were opened daily around shrew (Crocidura russula). The species and study area (at 06:30 hours, checked at 10:00 and at 13:30 hours, and the altitudinal margin of its distribution) were chosen on then closed for the night. All caught individuals were several grounds. First, owing to strong dependence on individually marked by toe clipping and immediately human habitations, local populations are discrete, released. highly structured, and easily identified. Second, owing Local population size was estimated for each site as to harsh climatic conditions, local populations are small the mean number of individuals captured per year. A and prone to local extinctions induced by demographic site occupancy rate was defined as the proportion of or environmental stochasticity. Third, this species years in which at least one individual was captured. A displays high dispersal ability and short life span, which site’s colonization rate was estimated as the number of should combine with these features to induce high annual transitions from an empty to an occupied state, population turnover rates. Finally, its high trappability divided by the total number of transitions from an should facilitate mark and recapture studies. As empty state. Extinction rate was similarly estimated as metapopulation dynamics are poorly documented in the number of transitions from an occupied to an empty mammals, this study system had the potential to state, divided by the total number of transitions from an contribute significantly to the field. occupied state. METHODS Habitat quality and connectivity Field sampling Habitat quality (or suitability) was estimated using Crocidura russula is a small insectivorous mammal the ecological-niche factor analysis (ENFA; Biomapper widespread in southwestern Europe. The life cycle is 3.2; Hirzel et al. 2002, 2004) with the median algorithm mostly annual (Jeanmaire-Besanc¸on 1988) and the (Hirzel and Arlettaz 2003) at a 25-m cell resolution. This mating system mostly monogamous (Cantoni and Vogel multivariate analysis extracts a series of independent 1989, Bouteiller and Perrin 2000). Breeding pairs defend factors (linear combinations of environmental variables) territories where they may rear several litters from that maximize the marginality and specialization of a March to September (Jeanmaire-Besanc¸on 1988). In the focal species, relative to the reference area. Marginality northern part of the species range (including the study measures how much environmental conditions in area), individuals are preferentially anthropophilic presence sites depart from average, and specialization below 600 m and strictly so at higher altitudes (Genoud measures the narrowness of their distributions, relative 1985), relying on thermally favorable sites (farms, to that of reference sites. ENFA requires only presence stables, and compost heaps) to meet the
Load more

Recommended publications
  • A Metapopulation Model with Discrete Size Structure
    A METAPOPULATION MODEL WITH DISCRETE SIZE STRUCTURE MAIA MARTCHEVA¤ AND HORST R. THIEME¦ Abstract. We consider a discrete size-structured metapopulation mo- del with the proportions of patches occupied by n individuals as de- pendent variables. Adults are territorial and stay on a certain patch. The juveniles may emigrate to enter a dispersers' pool from which they can settle on another patch and become adults. Absence of coloniza- tion and absence of emigration lead to extinction of the metapopulation. We de¯ne the basic reproduction number R0 of the metapopulation as a measure for its strength of persistence. The metapopulation is uniformly weakly persistent if R0 > 1. We identify subcritical bifurcation of per- sistence equilibria from the extinction equilibrium as a source of multiple persistence equilibria: it occurs, e.g., when the immigration rate (into occupied pathes) exceeds the colonization rate (of empty patches). We determine that the persistence-optimal dispersal strategy which maxi- mizes the basic reproduction number is of bang-bang type: If the number of adults on a patch is below carrying capacity all the juveniles should stay, if it is above the carrying capacity all the juveniles should leave. 1. Introduction A metapopulation is a group of populations of the same species which occupy separate areas (patches) and are connected by dispersal. Each sep- arate population in the metapopulation is referred to as a local population. Metapopulations occur naturally or by human activity as a result of habitat loss and fragmentation. An overview of the empirical evidence for the exis- tence of metapopulation dynamics can be found in [31].
    [Show full text]
  • Effective Population Size and Genetic Conservation Criteria for Bull Trout
    North American Journal of Fisheries Management 21:756±764, 2001 q Copyright by the American Fisheries Society 2001 Effective Population Size and Genetic Conservation Criteria for Bull Trout B. E. RIEMAN* U.S. Department of Agriculture Forest Service, Rocky Mountain Research Station, 316 East Myrtle, Boise, Idaho 83702, USA F. W. A LLENDORF Division of Biological Sciences, University of Montana, Missoula, Montana 59812, USA Abstract.ÐEffective population size (Ne) is an important concept in the management of threatened species like bull trout Salvelinus con¯uentus. General guidelines suggest that effective population sizes of 50 or 500 are essential to minimize inbreeding effects or maintain adaptive genetic variation, respectively. Although Ne strongly depends on census population size, it also depends on demographic and life history characteristics that complicate any estimates. This is an especially dif®cult problem for species like bull trout, which have overlapping generations; biologists may monitor annual population number but lack more detailed information on demographic population structure or life history. We used a generalized, age-structured simulation model to relate Ne to adult numbers under a range of life histories and other conditions characteristic of bull trout populations. Effective population size varied strongly with the effects of the demographic and environmental variation included in our simulations. Our most realistic estimates of Ne were between about 0.5 and 1.0 times the mean number of adults spawning annually. We conclude that cautious long-term management goals for bull trout populations should include an average of at least 1,000 adults spawning each year. Where local populations are too small, managers should seek to conserve a collection of interconnected populations that is at least large enough in total to meet this minimum.
    [Show full text]
  • Life History Evolution in Response to Changes in Metapopulation
    bioRxiv preprint doi: https://doi.org/10.1101/021683; this version posted October 9, 2015. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 Life history evolution in response to changes in metapopulation 2 structure in an arthropod herbivore 3 4 Authors: De Roissart A1, Wybouw N2,3, Renault D 4, Van Leeuwen T2, 3 & Bonte D1,* 5 6 Affiliations: 7 1 Ghent University, Dep. Biology, Terrestrial Ecology Unit, K.L. Ledeganckstraat 35, B-9000 8 Ghent, Belgium 9 2 Ghent University, Dep. Crop Protection, Laboratory of Agrozoology, Coupure Links 653, B- 10 9000 Ghent, Belgium 11 3 University of Amsterdam, Institute for Biodiversity and Ecosystem Dynamics, Science Park 12 904, 1098 XH Amsterdam, the Netherlands 13 4 Université de Rennes 1, UMR 6553 ECOBIO CNRS, Avenue du Gal Leclerc 263, CS 74205, 14 35042 Rennes Cedex, France 15 16 17 *Corresponding author: Dries Bonte, Ghent University, Dep. Biology, Terrestrial Ecology 18 Unit, K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium. Email: [email protected]; tel: 19 0032 9 264 52 13; fax: 0032 9 264 87 94 20 21 E-mail address of the co-authors:[email protected]; [email protected]; 22 [email protected]; [email protected]; [email protected] 23 24 Manuscript type: Standard paper 25 26 Running title: Metapopulation structure and life history evolution 27 28 Key-words: metapopulation-level selection, stochasticity, Tetranychus urticae 29 30 1 bioRxiv preprint doi: https://doi.org/10.1101/021683; this version posted October 9, 2015.
    [Show full text]
  • 6 Metapopulations of Butterflies
    Case Studies in Ecology and Evolution DRAFT 6 Metapopulations of Butterflies Butterflies inhabit an unpredictable world. Consider the checkerspot butterfly, Melitaea cinxia, also known as the Glanville Fritillary. They depend on specific host plants for larval development. The population size is buffeted by the vagaries of weather, availability of suitable host plants, and random demographic stochasticity in the small patches. The result is that local populations often go extinct when the host plants fail, or when larvae are unable to complete development before the winter. But butterflies also have wings. Even though the checkerspots are not particularly strong flyers (they move a maximum of a couple of kilometers and most individuals remain in their natal patch), butterflies occasionally move from one patch to another. Empty patches are eventually recolonized. So, over a regional scale the total number of butterflies remains nearly constant, despite the constant turnover of local populations. Professor Ilkka Hanski and his students in Finland have been studying the patterns of extinction and recolonization of habitat patches by the checkerspot butterflies for two decades on the small island of Åland in southwestern Finland. The butterflies on Åland can be described as a “metapopulation”, or “population of populations”, connected by migration. In the original formulation by Richard Levins, he imagined a case where each population was short-lived, and the persistence of the system depended on the re-colonization of empty patches by immigrants from other nearby source populations. Thus colonizations and extinctions operate in a dynamic balance that can maintain a species in the landscape of interconnected patches indefinitely.
    [Show full text]
  • Metapopulations and Metacommunities: Combining Spatial and Temporal Perspectives in Plant Ecology
    Journal of Ecology 2012, 100, 88–103 doi: 10.1111/j.1365-2745.2011.01917.x CENTENARY SYMPOSIUM SPECIAL FEATURE Metapopulations and metacommunities: combining spatial and temporal perspectives in plant ecology Helen M. Alexander1*, Bryan L. Foster1, Ford Ballantyne IV2, Cathy D. Collins3, Janis Antonovics4 and Robert D. Holt5 1Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045-7534, USA; 2Department of Ecology and Evolutionary Biology and Kansas Biological Survey, University of Kansas, Lawrence, KS 66045-7534, USA; 3Department of Biology, Colby College, Waterville, ME 04901-8840, USA; 4Department of Biology, University of Virginia, Charlottesville, VA 22904, USA; and 5Department of Biology, University of Florida, 223 Bartram Hall, P.O. Box 118525, Gainesville, FL 32611-8525, USA Summary 1. Metapopulation and metacommunity theories occupy a central role in ecology, but can be diffi- cult to apply to plants. Challenges include whether seed dispersal is sufficient for population connec- tivity, the role of seed banks and problems with studying colonization and extinction in long-lived and clonal plants. Further, populations often do not occupy discrete habitat patches. Despite these difficulties, we present case studies to illustrate explicit integration of spatial and temporal data in plant ecology. 2. First, on the population level, we focused on two early successional species that lack discrete hab- itat patches. Multi-year data sets taken with a grid approach and simple models permit the analysis of landscape dynamics that reflect regional as well as local processes. Using Silene latifolia,we examined colonization. We found evidence for seed dispersal and connectivity among populations across a large landscape.
    [Show full text]
  • Patch Dynamics and Metapopulation Theory: the Case of Successional Species
    Journal of Theoretical Biology (2001) 209 (3): 333-344. http://dx.doi.org/10.1006/jtbi.2001.2269 Patch Dynamics and Metapopulation Theory: The Case of Successional Species a a,b Priyanga Amarasekare and Hugh Possingham a National Center for Ecological Analysis and Synthesis, University of California, Santa Barbara, 735 State Street, Suite 300, Santa Barbara, CA, 93101-5504, U.S.A. b Departments of Zoology and Mathematics, The University of Queensland, St Lucia, QLD 4072, Australia Abstract We present a mathematical framework that combines extinction–colonization dynamics with the dynamics of patch succession. We draw an analogy between the epidemiological categorization of individuals (infected, susceptible, latent and resistant) and the patch structure of a spatially heterogeneous landscape (occupied–suitable, empty–suitable, occupied–unsuitable and empty– unsuitable). This approach allows one to consider life-history attributes that influence persistence in patchy environments (e.g., longevity, colonization ability) in concert with extrinsic processes (e.g., disturbances, succession) that lead to spatial heterogeneity in patch suitability. It also allows the incorporation of seed banks and other dormant life forms, thus broadening patch occupancy dynamics to include sink habitats. We use the model to investigate how equilibrium patch occupancy is influenced by four critical parameters: colonization rate, extinction rate, disturbance frequency and the rate of habitat succession. This analysis leads to general predictions about how the temporal scaling of patch succession and extinction–colonization dynamics influences long- term persistence. We apply the model to herbaceous, early-successional species that inhabit open patches created by periodic disturbances. We predict the minimum disturbance frequency required for viable management of such species in the Florida scrub ecosystem.
    [Show full text]
  • On the Principle of Competitive Exclusion in Metapopulation Models
    Appl. Math. Inf. Sci. 9, No. 4, 1739-1752 (2015) 1739 Applied Mathematics & Information Sciences An International Journal http://dx.doi.org/10.12785/amis/090411 On the Principle of Competitive Exclusion in Metapopulation Models Davide Belocchio, Roberto Cavoretto, Giacomo Gimmelli, Alessandro Marchino and Ezio Venturino∗ Dipartimento di Matematica “Giuseppe Peano”, Universita di Torino, via Carlo Alberto 10, 10123 Torino, Italy Received: 12 Oct. 2014, Revised: 12 Jan. 2015, Accepted: 13 Jan. 2015 Published online: 1 Jul. 2015 Abstract: In this paper we present and analyse a simple two populations model with migrations among two different environments. The populations interact by competing for resources. Equilibria are investigated. A proof for the boundedness of the populations is provided. A kind of competitive exclusion principle for metapopulation systems is obtained. At the same time we show that the competitive exclusion principle at the local patch level may be prevented to hold by the migration phenomenon, i.e. two competing populations may coexist, provided that only one of them is allowed to freely move or that migrations for both occur just in one direction. Keywords: populations, competition, migrations, patches, competitive exclusion 1 Introduction metapopulation concept becomes essential to describe the natural interactions. This paper attempts the development In this paper we consider a minimal metapopulation of such an issue in this framework. Note that another model with two competing populations. It consists of two recent contribution in the context of patchy environments different environments among which migrations are considers also a transmissible disease affecting the allowed. populations, thereby introducing the concept of As migrations do occur indeed in nature, [6], the metaecoepidemic models, [30].
    [Show full text]
  • Nf(N) , Lecture 8. Spatially-Structured Populations. Reading: Go
    FW662 Lecture 8 – Spatially-structured populations 1 Lecture 8. Spatially-structured populations. Reading: Gotelli, 2001, A Primer of Ecology, Chapter 4, pages 81-97. Hanski, I. 1996. Metapopulation ecology. Pages 13-43 in Rhodes, O. E., Jr., R. K. Chesser, and M. H. Smith (eds.). Population dynamics in ecological space and time. University Chicago Press, Chicago, Illinois, USA. Pulliam, H. R. 1996. Sources and sinks: empirical evidence and population consequences. Pages 45-69 in Rhodes, O. E., Jr., R. K. Chesser, and M. H. Smith (eds.). Population dynamics in ecological space and time. University Chicago Press, Chicago, Illinois, USA. Optional: Gilpin, M. E. 1987. Spatial structure and population vulnerability. Pages 125-139 in M. E. Soulé, ed. Viable Populations for Conservation. Cambridge University Press, New York, New York, USA. 189 pp. Kareiva, P. 1990. Population dynamics in spatially complex environments: theory and data. Pages 53-68 in Population Regulation and Dynamics, M. P. Hassell and R. M. May, eds. The Royal Society, London, United Kingdom. Traditional View of Populations Panmictic -- no selective mating. Frequency of genes in the population follows Hardy- Weinberg equilibrium. Equilibrium -- population reaches a carrying capacity. Extinction dependent on N. Homogeneous environment/habitat -- no spatial heterogeneity. Individuals equal (no heterogeneity of individuals). We have relaxed some of these assumptions in previous models: stochastic models, age- structured models. However, basically, previous models have been "traditional". Difficulty of incorporating spatial extension into population models Difficult to keep track of locations of organisms in field studies Computational problems of dealing with space in a theoretical manner are formidable, requiring computer models Spatial patterns in populations Traditional approach is a diffusion equation.
    [Show full text]
  • Is the Metapopulation Concept Applicable to the North Sea?
    Is the metapopulation concept applicable to the North Sea? Merel E. den Held Alterra-rapport 1928, ISSN 1566-7197 Uitloop 0 lijn 20 mm 15 mm 10 mm 5 mm Is the metapopulation concept applicable to the North Sea? 2 Alterra-rapport 1928 Is the metapopulation concept applicable to the North Sea? Merel E. den Held Alterra-rapport 1928 Alterra, Wageningen, 2009 Referaat Held, M.E. den, 2009. Is the metapopulation concept applicable to the North Sea? Wageningen, Alterra, Alterra-rapport 1928. 60 blz.; 7 figs.; 5 tables; 102 refs. The metapopulation concept could provide an additional way of designating areas for protective measures in the North Sea, by delineating habitat preferences and population dynamics. The current study looks into the applicability of the metapopulation concept to the North Sea underwater environment. It also seeks out species in the North Sea that could possibly be suitable metapopulations for study. The North Sea clearly is a heterogeneous environment, but habitat characteristics, like substratum type, tend to be wide ranged and without obvious physical barriers. Processes and structures in the seascape are mainly known on a rough scale, and even at that level, the available knowledge is only an interpretation from data. The same lack of knowledge is a bottleneck in defining connectivity among subpopulations, as dispersal capabilities are unknown for the majority of marine species. The species that seems most suitable for study in a metapopulation model in this test is the grey seal. Additionally, edible crab and cod emerged as species for potential use in a metapopulation model. Neither inhabit a discrete habitat patch, but both are known to have a strategy to ensure that their offspring recruits into their own population.
    [Show full text]
  • Dynamics of Infectious Diseases
    Chapter 17 11/17/03 3:15 PM Page 415 17. METAPOPULATION DYNAMICS OF INFECTIOUS DISEASES Matt J. Keeling, Ottar N. Bjørnstad, and Bryan T. Grenfell 17.1 INTRODUCTION John Donne’s famous line “No man is an island, entire of itself” has deep resonances for the dynamics of parasites. This is particularly true for microparasitic infections, such as viruses and bacteria, for which each suscep- tible host is a potential patch of favourable habitat. Propagules from infected “patches” can colonize others, followed by parasitic multiplication and “local” growth of the parasite population. Thus, at the scale of the host popu- lation, infectious dynamics bears strong analogies to metapopulation dynam- ics. Furthermore, host individuals are, more often than not, structured into local populations, within which contact among hosts may be very frequent and between which contacts may be less frequent. In this way, the spatiotem- poral dynamics and persistence of parasites are determined at two scales: the infrapopulation scale (a local population scale; parasites within hosts) and the metapopulation scale (spatial and/or social aggregation of hosts). The spa- tiotemporal dynamics of infection in human and domestic systems are of par- ticular academic interest because of the wealth of data combined with well-described natural histories. As a result of the dual spatial scales of regulation, an extended metapopu- lation paradigm is central to infectious disease dynamics in two important Ecology, Genetics, and Evolution 415 © 2004, Elsevier, Inc. of Metapopulations 0-12-323448-4 Chapter 17 11/17/03 3:15 PM Page 416 416 MATT J. KEELING ET AL.
    [Show full text]
  • Competitive Exclusion and Limiting Similarity: a Unified Theory
    International Institute for Tel: +43 2236 807 342 Applied Systems Analysis Fax: +43 2236 71313 Schlossplatz 1 E-mail: [email protected] A-2361 Laxenburg, Austria Web: www.iiasa.ac.at Interim Report IR-05-040 Competitive Exclusion and Limiting Similarity: A Unified Theory Géza Meszéna ([email protected]) Mats Gyllenberg ([email protected]) Liz Pásztor ([email protected]) Johan A. J. Metz ([email protected]) Approved by Ulf Dieckmann Program Leader, ADN August 2005 Interim Reports on work of the International Institute for Applied Systems Analysis receive only limited review. Views or opinions expressed herein do not necessarily represent those of the Institute, its National Member Organizations, or other organizations supporting the work. IIASA STUDIES IN ADAPTIVE DYNAMICS NO. 101 The Adaptive Dynamics Network at IIASA fosters the develop- ment of new mathematical and conceptual techniques for under- standing the evolution of complex adaptive systems. Focusing on these long-term implications of adaptive processes in systems of limited growth, the Adaptive Dynamics Network brings together scientists and institutions from around the world with IIASA acting as the central node. Scientific progress within the network is collected in the IIASA ADN Studies in Adaptive Dynamics series. No. 1 Metz JAJ, Geritz SAH, Meszéna G, Jacobs FJA, van No. 11 Geritz SAH, Metz JAJ, Kisdi É, Meszéna G: The Dy- Heerwaarden JS: Adaptive Dynamics: A Geometrical Study namics of Adaptation and Evolutionary Branching. IIASA of the Consequences of Nearly Faithful Reproduction. IIASA Working Paper WP-96-077 (1996). Physical Review Letters Working Paper WP-95-099 (1995).
    [Show full text]
  • ORIGINAL ARTICLE: Do Invasive
    Journal of Biogeography (J. Biogeogr.) (2010) 37, 1824–1834 ORIGINAL Do invasive species undergo ARTICLE metapopulation dynamics? A case study of the invasive Caspian gull, Larus cachinnans, in Poland Magdalena Lenda1*, Magdalena Zagalska-Neubauer2,3, Grzegorz Neubauer3 and Piotr Sko´rka4 1Institute of Nature Conservation, Polish ABSTRACT Academy of Sciences, Mickiewicza 33, 31-120 Aim The mechanisms of initial dispersal and habitat occupancy by invasive alien Krako´w, Poland, 2Institute of Environmental Sciences, Jagiellonian University, Gronostajowa species are fundamental ecological problems. Most tests of metapopulation 7, 30-387 Krako´w, Poland, 3Ornithological theory are performed on local population systems that are stable or in decline. In Station, Museum and Institute of Zoology, the current study we were interested in the usefulness of metapopulation theory Polish Academy of Sciences, Nadwis´lan´ska 108, to study patch occupancy, local colonization, extinction and the abundance of the 80-680 Gdan´sk, Poland, 4Institute of Zoology, invasive Caspian gull (Larus cachinnans) in its initial invasion stages. Poznan´ University of Life Sciences, Wojska Location Waterbodies in Poland. Polskiego 71 C, 60-625 Poznan´, Poland Methods Characteristics of the habitat patches (waterbodies, 35 in total) occupied by breeding pairs of Caspian gulls and an equal sample of randomly selected unoccupied patches were compared with t-tests. Based on presence– absence data from 1989 to 2006 we analysed factors affecting the probability of local colonization, extinction and the size of local populations using generalized linear models. Results Occupied habitat patches were significantly larger and less isolated (from other habitat patches and other local populations) and were located closer to rivers than empty patches.
    [Show full text]