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1. Ecological Systems in Hierarchical Perspecitive: Breaks in Community Structure and Other Consequences

Author:
Kolasa, Jerzy
Source:
Ecology 1989 v.70 no.1 pp. 36-47
ISSN:
0012-9658
Subject:
Platyhelminthes; aquatic insects; biogeography; birds; community structure; extinction; habitats; models; predation; prediction; rodents
Abstract:
... Explanation of the patterns of species abundances is important because it may help in understanding mechanisms structuring communities. A general conceptual model is proposed and examined as an alternative to previous propositions, which focused too narrowly on specific mechanisms. According to this model, viewing the structure of an environment as a nested hierarchy of habitat units provides a ge ...
DOI:
10.2307/1938410

2. Intraspecific Competition and Facilitation in a Northern Acorn Barnacle Population

Author:
Bertness, Mark D.
Source:
Ecology 1989 v.70 no.1 pp. 257-268
ISSN:
0012-9658
Subject:
Sessilia; adults; adverse effects; algae; habitats; intraspecific competition; littoral zone; predation; shade; solar radiation; survival rate; temperature; New England region
Abstract:
... The role of density—dependent mortality in shaping adult populations of the acorn barnacle, Semibalanus balanoides, was studied on a sheltered New England shore and revealed that high recruitment densities can have both positive and negative effects on barnacle survival. Recruitment greatly exceeded the capacity of the space to support adults in the three years of this study. At low tidal heights, ...
DOI:
10.2307/1938431

3. Island Biogeograhy of Montane Forest Mammals in the American Southwest

Author:
Lomolino, Mark V.; Brown, James H.; Davis, Russell
Source:
Ecology 1989 v.70 no.1 pp. 180-194
ISSN:
0012-9658
Subject:
Neotoma; chaparral; community structure; grasslands; habitats; immigration; islands; latitude; mammals; montane forests; paleoecology; species diversity; woodlands; Arizona; Colorado; New Mexico; Utah
Abstract:
... Information from packrat (Neotoma spp.) middens and other paleoenvironmental indicators was used to reconstruct Pleistocene distributions of macrohabitats in the American Southwest (Arizona, New Mexico, and southern Utah and Colorado). This revealed a system of southern montane forests that were isolated during the Pleistocene (primarily by woodlands) as well as today by grasslands, chaparral, and ...
DOI:
10.2307/1938425

4. Predation by Birds on Spruce Budworm Choristoneura Fumiferana: Functional, Numerical, and Total Responses

Author:
Crawford, Hewlette S.; Jennings, Daniel T.
Source:
Ecology 1989 v.70 no.1 pp. 152-163
ISSN:
0012-9658
Subject:
Cardellina canadensis; Choristoneura fumiferana; Junco; Turdidae; birds; diet; forest stands; forests; habitats; larvae; moths; overstory; population density; predation; predators; pupae; stomach; understory; Maine; New Hampshire
Abstract:
... This study examined the hypothesis that predation by forest birds restricts expansion of low—density populations of the spruce budworm Choristoneura fumiferana (Lepidoptera: Tortricidae). Bird populations were censused in spruce—fir stands of low to moderate spruce budworm density in northern New Hampshire and western Maine. Diets were determined from stomach contents of collected birds. Budworm p ...
DOI:
10.2307/1938422

5. Acorn Harvesting by Florida Scrub Jays

Author:
DeGange, Anthony R.; Fitzpatrick, John W.; Layne, James N.; Woolfenden, Glen E.
Source:
Ecology 1989 v.70 no.2 pp. 348-356
ISSN:
0012-9658
Subject:
Aphelocoma coerulescens; age structure; arthropods; breeding; crops; fruits; habitat preferences; habitats; harvesting; juveniles; shrublands; shrubs; summer; territoriality; warehouses
Abstract:
... We documented number of acorns eaten, cached, and retrieved by Florida Scrub Jays (Aphelocoma coerulescens coerulescens), through one full annual cycle and part of another, in an oak scrub habitat characterized by abundant and reliable annual acorn crops. Jays consumed acorns during all months, with highest consumption from September through February and lowest in June and July. From August throug ...
DOI:
10.2307/1937539

6. The Planned Introduction of Genetically Engineered Organisms: Ecological Considerations and Recommendations

Author:
Tiedje, James M.; Colwell, Robert K.; Grossman, Yaffa L.; Hodson, Robert E.; Lenski, Richard E.; Mack, Richard N.; Regal, Philip J.
Source:
Ecology 1989 v.70 no.2 pp. 298-315
ISSN:
0012-9658
Subject:
ancestry; biotechnology; cell biology; competitive exclusion; ecosystems; education programs; environmental impact; ethics; fertilizers; field experimentation; gene pool; genes; genetic engineering; genetic techniques and protocols; genetically modified organisms; greenhouse experimentation; habitats; hybridization; indigenous species; industry; interdisciplinary research; international cooperation; lignin; microbial communities; microorganisms; molecular biology; monitoring; natural selection; nitrogen fixation; pesticides; pests; phenotype; politics; population growth; risk; risk assessment; risk management; society; waste treatment
Abstract:
... The ecological and evolutionary aspects of planned introductions of transgenic organisms into the environment are considered in this report. The authors support the timely development of environmentally sound products, such as improved agricultural varieties, fertilizers, pest control agents, and microorganisms for waste treatment, through the use of advanced biotechnology within the context of a ...
DOI:
10.2307/1937535

7. Avian Predation on Anolis Lizards in the Northeastern Caribbean: Inter‐Island Contrast

Author:
McLaughlin, John F.; Roughgarden, Jonathan
Source:
Ecology 1989 v.70 no.3 pp. 617-628
ISSN:
0012-9658
Subject:
dry season; Anguilla anguilla; diet; islands; lizards; predators; body size; predation; field experimentation; Anolis; habitats; Falco sparverius; birds; French West Indies; Netherlands Antilles
Abstract:
... This paper presents results of a field study of avian predation on Anolis lizards on islands in the northeastern Caribbean, addressing the question of what causes annual fluctuation in lizard abundance. The two main potential avian predators, the Pearly—eyed Thrasher (Margarps fuscatus) and the American Kestrel (Falco sparverius), were studied on three adjacent islands in the northern Lesser Antil ...
DOI:
10.2307/1940213

8. Marsh Seed Banks of the Okefenokee Swamp: Effects of Hydrologic Regime and Nutrients

Author:
Gerritsen, Jeroen; Greening, Holly S.
Source:
Ecology 1989 v.70 no.3 pp. 750-763
ISSN:
0012-9658
Subject:
Carex; Eriocaulon; Nymphaea odorata; drawdown; drought; flowering; fruiting; germination; greenhouses; habitats; macrophytes; marshes; mature plants; nitrogen; nutrient availability; nutrient content; nutrients; phosphorus; plant growth; sediments; seedlings; seeds; swamps
Abstract:
... Seedling germination from the seed banks of two marshes in the Okenfenokee Swamp, a deep macrophyte marsh and a shallow sedge marsh, was examined in the greenhouse under three hydrologic regimes and four nutrient conditions. Experimental hydrologic conditions of 3—mo duration, were constant exposure (no standing water), 1—mo exposure followed by reinundation, and constant inundation, repeated four ...
DOI:
10.2307/1940225

9. A Neighborhood Analysis of Herbivory in Bouteloua Gracilis

Author:
Holmes, Robert D.; Jepson-Innes, Karen
Source:
Ecology 1989 v.70 no.4 pp. 971-976
ISSN:
0012-9658
Subject:
Aristida; Bouteloua gracilis; canopy; habitats; herbivores; risk; tillers
Abstract:
... This study examined whether an individual plant's risk of herbivory was affected by its nearest neighbor. Individually potted tillers of Bouteloua gracilis were placed in a natural habitat with one of two neighbors (B. gracilis conspecifics or Aristida spp.), and in one of two cover treatments (high: in center of neighbor canopy, and low: at periphery of canopy). After one month, the experimental ...
DOI:
10.2307/1941364

10. Estimates of Pre‐Settlement Insect Damage in Australian and North American Forests

Author:
Morrow, P. A.; Fox, L. R.
Source:
Ecology 1989 v.70 no.4 pp. 1055-1060
ISSN:
0012-9658
Subject:
Eucalyptus; broadleaved evergreens; forests; habitats; herbaria; herbivores; insects; leaves; trees; woodlands; Australia; North America
Abstract:
... Herbivores insect damage to broadleaved evergreen trees prior to widespread European disturbance of the environment was estimated from herbarium specimens collected in western North America and Australia. These data were used to determine whether the current pattern of higher levels of insect damage on Australian Eucalyptus trees than on comparable North American trees of similar habitat and leaf ...
DOI:
10.2307/1941374

11. Habitat Use and Habitat Overlap of Riparian Birds in Three Elevational Zones

Author:
Finch, Deborah M.
Source:
Ecology 1989 v.70 no.4 pp. 866-880
ISSN:
0012-9658
Subject:
birds; breeding; data collection; grasslands; habitat preferences; habitats; hills; lowlands; principal component analysis; riparian forests; shrublands; species diversity; variance; woodlands; Great Plains region; Rocky Mountain region; Wyoming
Abstract:
... I examined patterns of variance in habitat use and habitat overlap in 20 breeding bird species found along a riparian vegetational gradient in southeastern Wyoming to test whether habitat use in species differed (1) from availability of random habitat resources, (2) among elevation zones, and (3) between species that inhabited only one zone and species that occupied multiple zones. I sampled habit ...
DOI:
10.2307/1941355

12. Modeling Vertebrate Dispersal Distances: Alternatives to the Geometric Distribution

Author:
Miller, Gary L.; Carroll, Bradley W.
Source:
Ecology 1989 v.70 no.4 pp. 977-986
ISSN:
0012-9658
Subject:
habitats; models; probability; probability distribution; vertebrates
Abstract:
... The geometric probability distribution is a common way by which to model frequency distributions of vertebrate dispersal distances. This model has two weaknesses: (1) it requires that the probability of stopping, p, is constant across the range of habitat units, and (2) it provides no mechanism for modeling the maximum dispersal distance. The weaknesses of this model are discussed and a family of ...
DOI:
10.2307/1941365

13. The Ontogeny of Diet Selection in Fledgling Ospreys

Author:
Edwards, Thomas C.
Source:
Ecology 1989 v.70 no.4 pp. 881-896
ISSN:
0012-9658
Subject:
Dorosoma; Lepomis; Micropterus salmoides; Morone saxatilis; Pandion haliaetus; adults; bass; color; diet; eating habits; fledglings; forage; foraging; habitats; lakes; littoral zone; ontogeny; shad; siblings
Abstract:
... I studied the ontogeny of diet selection in fledgling Ospreys (Pandion haliaetus) in the 1985 and 1986 postfledging periods to (1) determine if young that forage from the same available fish resource base develop similar diets; (2) examine how diet choice is affected by interactions with conspecifics; (3) examine how within— and between—year differences in fish abundance in two different lake habi ...
DOI:
10.2307/1941356

14. Bivalve Growth and Higher Order Interactions: Importance of Density, Site, and Time

Author:
Peterson, Charles H.; Beal, Brian F.
Source:
Ecology 1989 v.70 no.5 pp. 1390-1404
ISSN:
0012-9658
Subject:
Mercenaria mercenaria; clams; estuaries; field experimentation; habitats; hydrodynamics; mixing; roughness; temporal variation; North Carolina
Abstract:
... Field experiments were conducted from 1980 to 1982 to test how shell growth of the suspension—feeding bivalve Mercenaria mercenaria within a single estuarine system around Cape Lookout, North Carolina, varied with (1) year, (2) density within enclosed 1—m² plots, (3) the presence of enclosure walls, (4) the source of the clams, (5) site, and (6) various two—way interactions between these factors. ...
DOI:
10.2307/1938198

15. Growth‐Mortality Trade‐Offs and the Evolution of Juvenile Life Histories in the Alcidae

Author:
Ydenberg, R. C.
Source:
Ecology 1989 v.70 no.5 pp. 1494-1506
ISSN:
0012-9658
Subject:
Alcidae; chicks; dynamic programming; evolution; fledglings; habitats; issues and policy; juveniles; life history; models; mortality; nests; parents; progeny; reproduction; seabirds
Abstract:
... The juvenile life history of each of the 22 living species in the avian family Alcidae is composed of a period in the nest followed by a move to the ocean (fledging), where development is completed. The age, degree of development, and the mass of the alcid chick at fledging are extraordinarily variable, both between and within species. The available information suggests that nests are safe places ...
DOI:
10.2307/1938208

16. Long‐Distance Dispersal and Colonization in the Bay Checkerspot Butterfly, Euphydryas Editha Bayensis

Author:
Harrison, Susan
Source:
Ecology 1989 v.70 no.5 pp. 1236-1243
ISSN:
0012-9658
Subject:
Euphydryas editha; adults; butterflies; colonizing ability; females; field experimentation; habitats; larvae
Abstract:
... Dispersal, patch finding, and colonization abilities of the Bay checkerspot butterfly (Euphydryas editha bayensis) were measured in field experiments. Butterflies released in non—habitat were capable of moving several kilometres to reach a distant habitat patch. However, their interhabitat movements appeared to be non—oriented, unless they were within 50 m of a suitable patch. To quantify coloniza ...
DOI:
10.2307/1938181

17. Species‐Area Relationship for Stream Fishes

Author:
Angermeier, Paul L.; Schlosser, Isaac J.
Source:
Ecology 1989 v.70 no.5 pp. 1450-1462
ISSN:
0012-9658
Subject:
environmental factors; extinction; fish; habitats; linear models; regression analysis; reproductive success; species diversity; streams; winter; Illinois; Minnesota; Panama
Abstract:
... We sampled riffles and pool habitats of small streams in Minnesota, Illinois, and Panama to examine variation in species—area relationships within and between the respective fish faunas. For six of the seven steams studies, habitat lume was a better predictor of species richness than was habitat area, and number of individuals was a better predictor of species richness than habitat volume. Slopes ...
DOI:
10.2307/1938204

18. A Model of Population Growth, Dispersal and Evolution in a Changing Environment

Author:
Pease, Craig M.; Lande, Russell; Bull, J. J.
Source:
Ecology 1989 v.70 no.6 pp. 1657-1664
ISSN:
0012-9658
Subject:
biogeography; environmental factors; extinction; genetic variance; glaciers; habitats; landscapes; models; population growth; quantitative traits
Abstract:
... The climatic and biotic conditions at any geographic location will change through time, for example, because of the advance of glaciers. If it is to avoid extinction, a species adapted to a moving habitat must either track its habitat spatially, or adapt genetically to the new environmental conditions. These processes of migration and evolution are important in determining continental biogeographi ...
DOI:
10.2307/1938100

19. A Simple Population Estimate Based on Simulation for Capture‐Recapture and Capture‐Resight Data

Author:
Minta, Steven; Mangel, Marc
Source:
Ecology 1989 v.70 no.6 pp. 1738-1751
ISSN:
0012-9658
Subject:
Monte Carlo method; badgers; bison; data collection; habitats; models; population distribution; probability distribution; radio telemetry
Abstract:
... The use of capture–resight data for population estimation has seldom been exploited. It offers potential flexibility and advantages to the design of biological investigations in which a population estimate is required. Presently, the Petersen model is the only method for estimating closed populations using capture—resight data. A simple Monte Carlo simulation method can lead to a full probability ...
DOI:
10.2307/1938108

20. Non‐Additive Impact of Blue Crabs and Spot on Their Prey Assemblages

Author:
Martin, Thomas H.; Wright, Russel A.; Crowder, Larry B.
Source:
Ecology 1989 v.70 no.6 pp. 1935-1942
ISSN:
0012-9658
Subject:
Callinectes sapidus; Leiostomus xanthurus; Ulva; algae; crabs; estuaries; field experimentation; fish; habitats; predation; predators; prediction; North Carolina
Abstract:
... We designed a field experiment to examine predator interactions–in particular, the effect of each predator on the growth and survival of the other, and to examine the effects of predation on prey assemblages–in particular, predation effects by each predator alone as well as together. Blue crabs (Callinectes sapidus) and the fish, spot (Leiostomus xanthurus), co—occur in Southeastern estuaries of t ...
DOI:
10.2307/1938123

21. Plant‐Feeding Nematodes in Deep‐Rooting Desert Ecosystems

Author:
Freckman, Diana W.; Virginia, Ross A.
Source:
Ecology 1989 v.70 no.6 pp. 1665-1678
ISSN:
0012-9658
Subject:
Larrea tridentata; Nematoda; Prosopis glandulosa; ammonium compounds; autumn; biogeochemical cycles; drilling; dunes; ecosystems; ectoparasites; grasslands; habitats; herbivores; landscapes; nitrates; plant growth; plant parasitic nematodes; playas; rooting; roots; soil biota; soil depth; soil water; spring; winter; Chihuahuan Desert; New Mexico
Abstract:
... In the Chihuahuan Desert of southern New Mexico, mesquite (Prosopis glandulosa) occurs in a variety of landscape positions where water may accumulate to varying depths. The structure of Chihuahuan Desert landscapes has changed dramatically in the past 100 yr with mesquite expanding from its original distribution (playa, arroyo) into grassland and dune ecosystems. Our objective was to examine spati ...
DOI:
10.2307/1938101

22. Retention and Transport of Nutrients in a Third‐Order Stream in Northwestern California: Hyporheic Processes

Author:
Triska, Frank J.; Kennedy, Vance C.; Avanzino, Ronald J.; Zellweger, Gary W.; Bencala, Kenneth E.
Source:
Ecology 1989 v.70 no.6 pp. 1893-1905
ISSN:
0012-9658
Subject:
biogeochemical cycles; habitats; models; nitrates; nutrients; permeability; roughness; solutes; streams; subsurface flow; summer; surface water; wells; California
Abstract:
... Chloride and nitrate were coinjected into the surface waters of a third—order stream for 20 d to examine solute retention, and the fate of nitrate during subsurface transport. A series of wells (shallow pits) 0.5—10 m from the adjacent channel were sampled to estimate the lateral interflow of water. Two subsurface return flows beneath the wetted channel were also examined. The conservative tracer ...
DOI:
10.2307/1938120