Source and sink dynamics of density-dependent otter (Lutra lutra) populations in rivers of central Finland.

abstract：:Synchronous leaf production has been proposed as a mechanism to reduce herbivore damage to young leaves by satiating herbivores. To test this hypothesis, I measured leaf production, leaf survivorship, and herbivore damage on juveniles of Gustavia superba (H.B.K.) Berg (Lecythidaceae), in two sites in Central Panama. L...

journal_title：Oecologia

authors： Aide TM

更新日期：1991-12-01 00:00:00

abstract：:Short-term effects of environmental perturbations on various life history traits are reasonably well documented in birds and mammals. But, in the present context of global climate change, there is a need to consider potential long-term effects of natal conditions to better understand and predict the consequences of th...

journal_title：Oecologia

authors： Nevoux M,Weimerskirch H,Barbraud C

更新日期：2010-02-01 00:00:00

abstract：:Many ecologically generalized populations are composed of relatively specialized individuals that selectively consume a subset of their population's diet, a phenomenon known as 'individual specialization'. The Niche Variation Hypothesis posits that this individual specialization can arise during ecological release if ...

journal_title：Oecologia

authors： Snowberg LK,Hendrix KM,Bolnick DI

更新日期：2015-05-01 00:00:00

abstract：:The life ofOncopeltus fasciatus centers on the seeds of milkweeds (Asclepiadaceae,Asclepias syriaca in this study). Adults reproduce prolifically on these seeds, but they engage in only half as much copulation and lay only a few eggs when fed milkweed buds and flowers instead. They can not maintain body weight on a di...

journal_title：Oecologia

authors： Ralph CP

更新日期：1976-06-01 00:00:00

abstract：:No definitive explanation for the form of the relationship between species diversity and ecosystem productivity exists nor is there agreement on the mechanisms linking diversity and productivity across scales. Here, we examine changes in the form of the diversity-productivity relationship within and across the plant c...

journal_title：Oecologia

authors： Jennings MD,Williams JW,Stromberg MR

更新日期：2005-05-01 00:00:00

abstract：:A simulation program on the germination of winter annuals is written in such a way that the influence of changing environmental conditions on germination characteristics such as the time of germination, the percentage of germination and the distribution function of germination is described as well as possible in accor...

journal_title：Oecologia

authors： Janssen JG

更新日期：1974-09-01 00:00:00

abstract：:Snail hosts of different ages constitute different resource environments for larval trematodes because each individual has a particular energy budget and energy allocation pattern at the time of infection. Effects of monomiracidial trematode infections on shell growth, body dry weight and reproductive effort of the sn...

journal_title：Oecologia

authors： Gérard C,Théron A

更新日期：1997-11-01 00:00:00

abstract：:Invasive generalist ectoparasites provide a tool to study factors affecting expansion rates. An increase in the number of host species may facilitate geographic range expansion by increasing the number of suitable habitats and by affecting local extinction and colonization rates. A geographic perspective on parasite h...

journal_title：Oecologia

authors： Välimäki P,Kaitala A,Madslien K,Härkönen L,Várkonyi G,Heikkilä J,Jaakola M,Ylönen H,Kortet R,Ytrehus B

更新日期：2011-08-01 00:00:00

abstract：:The photosynthetic pathways of 42 species of the genusEuphorbia growing wild, naturalized or cultivated in Egypt were investigated. The criteria used included the δ13C- and δD-values and Kranz anatomy of the leaves. There is a relationship between the photosynthetic pathway and the ecological conditions in the habitat...

journal_title：Oecologia

authors： Batanouny KH,Stichler W,Ziegler H

更新日期：1991-09-01 00:00:00

abstract：:There is considerable theoretical evidence that a trade-off between competitive and colonization ability enables species coexistence. However, empirical studies testing for the presence of a competition-colonization (CC) trade-off and its importance for species coexistence have found mixed results. In a microcosm expe...

journal_title：Oecologia

authors： Limberger R,Wickham SA

更新日期：2011-11-01 00:00:00

abstract：:The abundance and composition of the submerged macrophyte seed bank in the Doñana marsh (southwestern Spain) was evaluated to assess its relationship with the overlying vegetation. The results obtained demonstrate the existence of a dense seed-bank, both in terms of the number of seeds and their biomass, which represe...

journal_title：Oecologia

authors： Grillas P,Garcia-Murillo P,Geertz-Hansen O,Marbá N,Montes C,Duarte CM,Tan Ham L,Grossmann A

更新日期：1993-05-01 00:00:00

abstract：:This study examines the effect of different densities and the removal of all neighbours at different stages of development on all components of reproduction in the inbreeding annual Thlaspi arvense L. A 64-fold increase in density significantly reduced all repooductive components. The number of flower buds per plant w...

journal_title：Oecologia

authors： Matthies D

更新日期：1990-05-01 00:00:00

abstract：:Increased biological diversity due to invasion by non-indigenous species (NIS) is a global phenomenon with potential effects on trophic interactions and ecosystem processes in the invaded habitat. We assessed the effects of resource availability and invasion of three non-indigenous invertebrate grazers (two crustacean...

journal_title：Oecologia

authors： Wikström SA,Hillebrand H

更新日期：2012-01-01 00:00:00

abstract：:Individuals of the collembolan species Tomocerus flavescens from a beech wood on limestone near Göttingen (West Germany) were fed with C-14-labelled algae in the laboratory. On an average, T. flavescens exchanged almost all of its endogenous carbon after 3.4 moults. In periods of starvation the interval between two ec...

journal_title：Oecologia

authors： Wolters V

更新日期：1985-01-01 00:00:00

abstract：:On a shallow sand flat at Princess Royal Harbour near Albany, Western Australia, the brown macrophyte Hormosira banksii attaches to shells of infaunal bivalves. Hormosira occupies shells of Katelysia rhytiphora in preference to K. scalarina. We proposed and tested four hypotheses to explain this host occupation patter...

journal_title：Oecologia

authors： Black R,Peterson CH

更新日期：1987-09-01 00:00:00

abstract：:Diel vertical migration (DVM) of herbivorous zooplankton is a widespread behavioural phenomenon in freshwater ecosystems. So far only little attention has been paid to the impact of DVM on the phytoplankton community in the epilimnion. Some theoretical models predict that algal population growth in the epilimnion shou...

journal_title：Oecologia

authors： Reichwaldt ES,Wolf ID,Stibor H

更新日期：2004-11-01 00:00:00

abstract：:We tested, through field experiments and simulation models, the hypothesis that fruit-searching tephritid fruit flies adjust their within-tree search persistence according to the sequence and timing of encounters with parasitized (i.e. egg-infested) and unparasitized Crataegus sp. host fruit. In the field, we presente...

journal_title：Oecologia

authors： Roitberg BD,Prokopy RJ

更新日期：1984-04-01 00:00:00

abstract：:Intraspecific positive relationships between abundance and occupancy are observed for many species, suggesting that the same processes drive local and regional species dynamics. Two main groups of mechanisms explain this relationship: spatiotemporal variation in local population growth rates due to variation in habita...

journal_title：Oecologia

authors： Östman Ö

更新日期：2011-03-01 00:00:00

abstract：:There is an increasing ecological interest in understanding the gradients in H(2)(18)O enrichment in leaf water (i.e. a Péclet effect), because an appreciation of the significance of the Péclet effect is important for improving our understanding of the mechanistic processes affecting the (18)O composition of leaf wate...

journal_title：Oecologia

authors： Barbour MM,Roden JS,Farquhar GD,Ehleringer JR

更新日期：2004-02-01 00:00:00

abstract：:The influence of ant attendance on parasitization of the larvae of three hawthorn psyllid species [Cacopsylla peregrina Förster, C. melanoneura Förster, C. crataegi (Schrank)] was studied over 2 years. All three psyllid species had low parasitization rates. However, the ant-attended C. crataegi was almost exclusively ...

journal_title：Oecologia

authors： Novak H

更新日期：1994-09-01 00:00:00

abstract：:The reproductive behaviour of the toad Bufo calamita was studied in a large population in the northern Rhineland, Germany. Toads bred at four spatially separated but neighbouring areas including 34 breeding ponds. Three methods were applied to monitor quantitatively the intensity of breeding and migratory activity: ca...

journal_title：Oecologia

authors： Sinsch U

更新日期：1988-08-01 00:00:00

abstract：:Heavy damage of the mountain birch foliage, as well as application of small amounts of insect frass to the soil beneath the trees, reduced growth of Epirrita autumnata larvae reared in these trees in the following year. Foliage damage in the previous year decreased larval survival, too. Both foliage damage and insect ...

journal_title：Oecologia

authors： Haukioja E,Suomela J,Neuvonen S

更新日期：1985-02-01 00:00:00

abstract：:Intra-colony demography and life history characteristics of neotropical Africanized and temperate European honey bearaces were compared under simulated feral conditions. Major differences in colony demography were found which nevertheless resulted in some similar reproductive characteristics. European colonies were la...

journal_title：Oecologia

authors： Winston ML,Dropkin JA,Taylor OR

更新日期：1981-03-01 00:00:00

abstract：:There are three major components to plant structure relevant to searching parasitoids: 1) plant size or surface area, 2) the variation among plant parts (structural heterogeneity), such as seed heads, flowers and nectaries, and heterogeneous surfaces (e.g. glabrous, hirsute), and 3) the connectivity of parts or plant ...

journal_title：Oecologia

authors： Andow DA,Prokrym DR

更新日期：1990-02-01 00:00:00

abstract：:Bythotrephes cederstroemii Schoedler, a predatory freshwater zooplankter (Crustacea: Cladocera), was first found in the Laurentian Great Lakes in December 1984. The first individuals were from Lake Huron, followed in 1985 with records from Lakes Erie and Ontario. By late August, 1986 the species had spread to southern...

journal_title：Oecologia

authors： Lehman JT

更新日期：1987-12-01 00:00:00

abstract：:The fate of individual plants of Helianthus annuus was monitored in populations sown at a density of 650 seeds m-2. Ninety six percent of the seeds germinated but only fifty two percent of the seedlings survived to the end of the experiment due to self-thinning. Whilst the seedlings emerged over only four days the cot...

journal_title：Oecologia

authors： Watkinson AR,Lonsdale WM,Firbank LG

更新日期：1983-02-01 00:00:00

abstract：:Shorter male larval and pupal durations were sufficient to produce the protandrous emergence pattern of the black swallowtail butterfly. In 9 broods observed under natural conditions, the first male was seen 7.1±6.5 days before the first female, although the peak of captures relative to the first capture was similar i...

journal_title：Oecologia

authors： Lederhouse RC,Finke MD,Scriber JM

更新日期：1982-06-01 00:00:00

abstract：:Ecological stoichiometry has advanced food web ecology by emphasising the importance of food quality over food quantity for herbivores. Here, we focus on the effects of abiotic factors such as nutrients and light (known to influence food quality) on grazer growth rates. As model organism we used the mudsnail Potamopyr...

journal_title：Oecologia

authors： Liess A,Lange K

更新日期：2011-09-01 00:00:00

abstract：:Although ontogenetic changes in the carbon isotope ratios of marine fauna have been well studied those of freshwater organisms have not. As a result, we may have a less than adequate assessment of the incorporation of allochthonous detritus into freshwater foodwebs. This study found a δ13C range of 9‰ for crayfish (Or...

journal_title：Oecologia

authors： France R

更新日期：1996-07-01 00:00:00

abstract：:Energy budgets explain how organisms allocate energetic intake to accomplish essential processes. A likely life history trade-off occurs between growth and immune response in juvenile organisms, where growth is important to avoid predation or obtain larger prey and immune response is essential to survival in the prese...

journal_title：Oecologia

authors： Korfel CA,Chamberlain JD,Gifford ME

更新日期：2015-10-01 00:00:00