Small

This collection of articles shows the study area locations of papers that cited this paper

Description

Bestelmeyer, B.T. and J.A. Wiens. 1996. The effects of land use on the structure of ground-foraging ant communities in the Argentine Chaco. Ecological Applications, 16(4), 1225-1240. DOI:10.2307/2269603

latest article added on January 2015

ArticleFirst AuthorPublished
LONG-TERM EFFECTS OF UNGULATES ON PERFORMANCE, ABUNDANCE, AND SPATIAL DISTRIBUTION OF TWO MONTANE HERBS.Gómez, José M. 2005. LONG-TERM EFFECTS OF UNGULATES ON PERFORMANCE2005

LONG-TERM EFFECTS OF UNGULATES ON PERFORMANCE, ABUNDANCE, AND SPATIAL DISTRIBUTION OF TWO MONTANE HERBS.

Keywords

Cruciferae;effect of microhabitat;Erysimum baeticum;Erysimum mediohispanicum;habitat distribution;mammal herbivory;Mediterranean mountains;plant population dynamics;postdispersal seed predation;seedling survival;short-lived perennial herbs;spatial structure of plant populations

Abstract

Herbivores highly reduce the performance of many plant species. However, little empirical information exists on the real effect that these organisms have on plant populations. With a long-term (seven-year) ungulate exclusion experiment in two areas of southeastern Spain, I demonstrated that these organisms can affect not only individual performance, but also the population dynamics and spatial structure of two short-lived monocarpic herbs, Erysimum mediohispanicum and E. baeticum. There was between-year and among-microhabitat variability in damage, with plants growing under shrubs being less damaged than those growing in open sites. Ungulates consumed flowers and fruits, severely decreasing plant reproductive output. The postdispersal seed predation rate increased after ungulates were excluded, presumably as a consequence of the relaxation of competition between seed predators and ungulates. The effect of ungulates on Erysimum early establishment was nonsignificant, although >50% of Erysimum seedlings died due to ungulate trampling. The exclusion experiment also revealed that, as a consequence of their impact on seed production, ungulates affected the population dynamics of their host plants; their removal produced a significant increase in the abundance of the two studied plant species. Furthermore, habitat distribution of plants was also influenced by the activity of ungulates. In control plots, most Erysimum individuals grew under the canopy of co-occurring shrubs. In contrast, a dramatic spatial redistribution of plants occurred in ungulate-excluded plots, where they started to colonize open sites. Consequently, the spatial structure of the plants excluded from ungulates significantly differed from that in control plots and became statistically similar to the structure expected according to the cover of every microhabitat. Finally, this experiment revealed that, for plants inhabiting heterogeneous landscapes, abundance and spatial structure are tightly related. Thus, I found that abundance increased in ungulate-excluded plots due not to a general and homogeneous increase, but to a significant increase in those microhabitats inaccessible to ungulates in control plots. These findings suggest that herbivory effects on plants are intricate, affecting not only their performance or population dynamics, but also their habitat distribution and niche structure.

Authors

Gómez, José M.

Year Published

2005

Publication

Ecological Monographs

Locations
DOI

10.1890/04-0722

This article contributed by:

Ecological Society of America

Does desertification diminish biodiversity? Enhancement of ant diversity by shrub invasion in south-western USABestelmeyer, BT2005

Does desertification diminish biodiversity? Enhancement of ant diversity by shrub invasion in south-western USA

Keywords

desert grassland; Dorymyrmex bicolor; Forelius; Formicidae; functional group; Prosopis glandulosa

Abstract

The conversion of desert grasslands to shrublands is a long-standing concern in the south-western United States, but the effects of this change on native animals defy generalization. Here, I consider evidence that shrub invasion and encroachment, particularly that of honey mesquite (Prosopis glandulosa), has led to increasing ecological dominance and diversity of ants in general, as well as increases in specific native taxa. The effects of shrub invasion on ants were measured at two scales: (1) between Chihuahuan Desert landscapes that vary slightly in temperature and strongly in the dominance of mesquite, and (2) across variation in mesquite density occurring within a generally mesquite-dominated landscape. Ant richness and numerical dominance was measured at pitfall traps over 2 years and baits were used to assess ecological dominance across different temperatures. The mesquite-dominated Jornada site harboured four times the number of ant foragers found at the relatively 'pristine' Sevilleta site, with several ecologically dominant taxa driving this pattern, especially Dorymyrmex bicolor. Species richness and ecological dominance were also greatest at the Jornada. Within the Jornada landscape, turnover in species composition was related to mesquite density, but local richness and abundance was unrelated to mesquite density. Coupled with the results of previous manipulative experiments and comparative studies, there is support for the notion that ant diversity is not negatively affected by shrub invasion but that several taxa prosper from it. The Jornada is uniquely saturated by dominant ant taxa, perhaps as a consequence of an overall high level of shrub availability that provides a reliable source of carbohydrate-rich plant exudates. This raises important questions about the relationship between environmental degradation, ecosystem productivity, and animal diversity.

Authors

Bestelmeyer, BT

Year Published

2005

Publication

Diversity And Distributions

Locations
DOI

10.1111/j.1366-9516.2005.00122.x

Forest fragmentation in central Amazonia and its effects on litter-dwelling antsCarvalho, Karine S.1999

Forest fragmentation in central Amazonia and its effects on litter-dwelling ants

Keywords

Amazon; Ants; Brazil; Edge effects; Forest fragmentation; Habitat isolation

Abstract

We assessed responses of ants nesting in twigs in the litter layer to habitat changes associated with forest fragmentation in central Amazonia. Ants were collected along transects located at nine distances (5, 20, 40, 60, 100, 200, 300, 400, 500 m) from the edges of two isolated 100-ha fragments and two continuous-forest sites. In total, 2880 m2 of litter were examined for the presence of ant colonies. We detected a significant decrease in litter depth with increasing distance to forest edge, and an increase and then decrease in the average diameter-at-breast-height (DBH) of large trees (DBH⩾10 cm), and in tree basal area. Distance to forest edge significantly affected ant species composition and this effect was partly attributable to variation in litter depth. With the exception of one fragment, no significant changes in ant nest densities or species richness were found with increasing distance to forest edge. However, species richness of ants was greater in continuous forest than in both fragments. Furthermore, most species (65.8%) had greater nest densities in continuous forest. These results suggest that edge and isolation effects both play a role in structuring litter-dwelling ant communities in Amazonian forest remnants.

Authors

Carvalho, Karine S. and Vasconcelos, Heraldo L.

Year Published

1999

Publication

Biological Conservation

Locations
DOI

10.1016/S0006-3207(99)00079-8

Patterns of diversity and composition of Mediterranean ground ant communities tracking spatial and temporal variability in the thermal environmentRetana, J.2000

Patterns of diversity and composition of Mediterranean ground ant communities tracking spatial and temporal variability in the thermal environment

Keywords

No keywords available

Abstract

The present study analyzed ant community structure and the factors affecting it in the Spanish Mediterranean area. The aim of this study was to test whether temperature controls the composition and diversity of the ground ant fauna and the spatial and temporal distribution of dominance groups along adjacent communities. The main descriptors of community structure (except perharps species richness) were found to vary along the gradient of vegetation cover: increased vegetation cover resulted in an increase in the relative abundance of the most common species, which led to a significant decrease in species evenness, together with a reduction in total ant density on the ground. In open habitats, dominant and subordinate species were abundant during different periods of the day, and this led to an increase in species evenness. In areas with high vegetation cover, dominants benefited from the lower temperatures by lengthening their periods of activity. This resulted in a decrease in the abundance of subordinate species, and in lower evenness. Seasonal patterns in community structure tracked temperature fluctuations and varied between habitat types. Evenness was similar in the two habitat types in spring, but increased in grasslands and decreased in shrublands/forests in summer. Species richness did not vary between seasons or habitat types. The relative abundance of dominance groups in the two types of habitats showed a different pattern between seasons. In grasslands, subordinates increased and dominants decreased their relative abundance from spring to summer, while in shrublands/forests, the opposite pattern was found. The overall conclusion from this study is that ground ant communities in open areas are primarily regulated by temperature variations, while in shrublands and forests, dominant species are more abundant, and competitive interactions appear to be the major structuring force.

Authors

Retana, J. and Cerdá, X.

Year Published

2000

Publication

Oecologia

Locations
DOI

10.1007/s004420051031

ANT BIODIVERSITY IN SEMIARID LANDSCAPE MOSAICS: THE CONSEQUENCES OF GRAZING VS. NATURAL HETEROGENEITYBestelmeyer, Brandon T.2001

ANT BIODIVERSITY IN SEMIARID LANDSCAPE MOSAICS: THE CONSEQUENCES OF GRAZING VS. NATURAL HETEROGENEITY

Keywords

ants; canonical correspondence analysis; desert grassland; diversity; Formicidae; grazing; habitat classification; shortgrass steppe; soil texture

Abstract

The conservation of biodiversity in landscape mosaics requires an under- standing of the impacts of human land use within mosaic elements and an evaluation of the biological uniqueness of different elements. We address these issues by examining patterns of ant diversity in three semiarid rangeland landscapes used predominantly for grazing. These landscapes lie along a regional gradient from shortgrass steppe through a transitional zone to desert grassland, along which climate and ant species composition vary. Within each landscape, we compared the effects of grazing and natural variation in soils and vegetation on ant diversity and community composition. Grazing had little effect on ant richness, diversity, or composition at the transitional zone or the desert grassland site, but ungrazed areas at the shortgrass steppe site had a higher overall richness and favored the abundance of some species. Some samples of saltbush ( Atriplex canescens ) shrubland were similar to ungrazed samples in richness and species composition. In both the tran- sitional zone and the desert grassland, creosotebush ( Larrea tridentata )-dominated habitats harbored comparatively species-rich and distinct ant communities. In addition, mesquite ( Prosopis glandulosa ) coppice dunes at the desert grassland site favored the abundance of several species that were rare across the site. Canonical correspondence analysis revealed that variation in soil strength and texture best explained community variation at the short- grass steppe site, whereas soil texture and associated differences in shrub density best explained differences in composition at the transitional and desert grassland sites. The characterization of habitats based upon vegetation classification did not adequately reflect environmental variation that was important to ants in shortgrass steppe, but reflected im- portant soil textural variation in the transitional and desert grassland sites. These results suggest that ant conservation in these semiarid rangelands should emphasize patterns of variation in soil properties. The results add to a growing consensus that a variety of variables determined by the responses of several focal taxa may be needed to characterize biodiversity patterns.

Authors

Bestelmeyer, Brandon T. and Wiens, John A.

Year Published

2001

Publication

Ecological Applications

Locations
DOI

10.1890/1051-0761(2001)011[1123:ABISLM]2.0.CO;2

This article contributed by:

Ecological Society of America

Influence of small-scale disturbances by kangaroo rats on Chihuahuan Desert antsSchooley, R. L.2000

Influence of small-scale disturbances by kangaroo rats on Chihuahuan Desert ants

Keywords

Ecosystem engineers, Disturbances, Formicidae, Heteromyidae, Spatial scale

Abstract

Banner-tailed kangaroo rats ( Dipodomys spectabilis ) are prominent ecosystem engineers that build large mounds that influence the spatial structuring of fungi, plants, and some ground-dwelling animals. Ants are diverse and functionally important components of arid ecosystems; some species are also ecosystem en- gineers. We investigated the effects of patch disturbances created by D. spectabilis mounds on ant assemblages in a Chihuahuan Desert grassland in southern New Mexico by using pitfall traps in a paired design (mound vs. ma- trix). Although the disturbances did not alter species richness or harbor unique ant communities relative to the matrix, they did alter species composition; the abun- dances of 6 of 26 species were affected. The distur- bances might also act to disrupt spatial patterning of ants caused by other environmental gradients. In contrast to previous investigations of larger-scale disturbances, we detected no effects of the disturbances on ants at the functional-group level. Whether ant communities re- spond to disturbance at a functional-group or within- functional-group level may depend on the size and inten- sity of the disturbance. Useful functional-group schemes also may be scale-dependent, however, or species may respond idiosyncratically. Interactions between distur- bance-generating mammals and ants may produce a nest- ed spatial structure of patches.

Authors

Schooley, R. L., Bestelmeyer, B. T. and Kelly, J. F.

Year Published

2000

Publication

Oecologia

Locations
DOI

10.1007/PL00008885

Effects of feral horses in Great Basin landscapes on soils and ants: Direct and indirect mechanismsBeever, E.A.2006

Effects of feral horses in Great Basin landscapes on soils and ants: Direct and indirect mechanisms

Keywords

Equus caballus; Formica; Pogonomyrmex; Nevada; Disturbance; Conservation

Abstract

We compared soil-surface penetration resistance and abundance of ant mounds at 12 western Great Basin sites (composed of 19 plots) either grazed by feral horses (Equus caballus) or having had horses removed for the last 10–14 years. Across this broad spatial domain (3.03 million ha), we minimized confounding due to abiotic factors by selecting horse-occupied and horse-removed sites with similar aspect, slope, fire history, grazing pressure by cattle (minimal to none), and dominant vegetation (Artemisia tridentata). During both 1997 and 1998, we found 2.2–8.4 times greater abundance of ant mounds and 3.0–15.4 times lower penetration resistance in soil surfaces at horseremoved sites. In 1998, thatched Formica ant mounds, which existed predominately at high elevations, were 3.3 times more abundant at horse-removed sites, although abundance varied widely among sites within treatments. Several types of analyses suggested that horses rather than environmental variability were the primary source of treatment differences we observed in ecosystem components. Tests of several predictions suggest that alterations occurred through not only direct effects, but also indirect effects and potentially feedback loops. Free-roaming horses as well as domestic grazers should be considered in conservation planning and land management in the Great Basin, an ecoregion that represents both an outstanding conservation opportunity and challenge.

Authors

Beever, E.A. and Herrick, J.E.

Year Published

2006

Publication

Journal of Arid Environments

Locations
DOI

10.1016/j.jaridenv.2005.11.006

Using ants as bioindicators in land management: simplifying assessment of ant community responsesAndersen, Alan N.2002

Using ants as bioindicators in land management: simplifying assessment of ant community responses

Keywords

environmental assessment; land-use impacts; monitoring; sampling protocols; SO2

Abstract

1 The indicator qualities of terrestrial invertebrates are widely recognized in the context of detecting ecological change associated with human land-use. However, the use of terrestrial invertebrates as bioindicators remains more a topic of scientific discourse than a part of land-management practice, largely because their inordinate numbers, taxonomic challenges and general unfamiliarity make invertebrates too intimidating for most land-management agencies. Terrestrial invertebrates will not be widely adopted as bioindicators in land management until simple and efficient protocols have been developed that meet the needs of land managers. 2 In Australia, ants are one group of terrestrial insects that has been commonly adopted as bioindicators in land management, and this study examined the reliability of a simplified ant assessment protocol designed to be within the capacity of a wide range of land managers. 3 Ants had previously been surveyed intensively as part of a comprehensive assessment of biodiversity responses to SO2 emissions from a large copper and lead smelter at Mt Isa in the Australian semi-arid tropics. This intensive ant survey yielded 174 species from 24 genera, and revealed seven key patterns of ant community structure and composition in relation to habitat and SO2 levels. 4 We tested the extent to which a greatly simplified ant assessment was able to reproduce these results. Our simplified assessment was based on ant ‘bycatch’ from bucket-sized (20-litre) pitfall traps used to sample vertebrates as part of the broader biodiversity survey. We also greatly simplified the sorting of ant morphospecies by considering only large (using a threshold of 4 mm) species, and we reduced sorting time by considering only the presence or absence of species at each site. In this manner, the inclusion of ants in the assessment process required less than 10% of the effort demanded by the intensive ant survey. 5 Our simplified protocol reproduced virtually all the key findings of the intensive survey. This puts effective ant monitoring within the capacity of a wide range of land managers.

Authors

Andersen, Alan N., Hoffmann, Benjamin D., Muller, Warren J. and Griffiths, Anthony D.

Year Published

2002

Publication

Journal of Applied Ecology

Locations
DOI

10.1046/j.1365-2664.2002.00704.x

Landscape structure as an indicator of biodiversity: matrix effects on species richnessDauber, Jens2003

Landscape structure as an indicator of biodiversity: matrix effects on species richness

Keywords

Apoidea; Formicidae; Plants, matrix; Conservation management; Agricultural landscape

Abstract

Sustainable conservation management in cultivated landscapes urgently needs indicators that provide quantitative links between landscape patterns and biodiversity. As a contribution to this aim, the influence of the matrix surrounding managed grassland sites on species richness of ants, wild bees and vascular plants was investigated at two different scales (50 and 200 m radius). In addition, patch variables describing habitat quality were included in the analyses. Species richness of the three taxa was not significantly inter-correlated. Multiple linear regression analysis revealed significant predictor variables for the species richness of the different taxa at both matrix scales. The variation of the matrix radius had no impact on the variance explanation of the regression models. The degree of variance explained by the regression models varied between taxa (bees>plants>ants). Moreover, the predictive variables were different for the taxa, with the regression model for wild bees including both patch and matrix variables, that for plants richness including patch variables only, and that for ants including matrix variables only. We conclude that landscape diversity and percentage cover of certain land-use types might serve as useful indicators for species richness at the landscape scale. However, the specific response patterns revealed in our study suggest that a variety of taxa must be included in this type of approach.

Authors

Dauber, Jens, Hirsch, Michaela, Simmering, Dietmar, Waldhardt, Rainer, Otte, Annette and Wolters, Volkmar

Year Published

2003

Publication

Agriculture, Ecosystems & Environment

Locations
DOI

10.1016/S0167-8809(03)00092-6

The trade-off between thermal tolerance and behavioural dominance in a subtropical South American ant communityBestelmeyer, Brandon T.2000

The trade-off between thermal tolerance and behavioural dominance in a subtropical South American ant community

Keywords

competition; Formicidae; functional types; microclimate; stress

Abstract

1. The distribution, ecology, and behaviour of ants (Hymenoptera: Formicidae) is profoundly influenced by environmental stress and competition. As in plants, trade-offs in adaptations to these factors are the basis for functional classifications of ant taxa and communities at a global scale. 2. Theory predicts a trade-off between stress tolerance and competitive dominance in both plants and ants. In ants, low temperature is thought to be stressful, so I hypothesized that there would be a positive relationship between temperature and behavioural dominance. I evaluated this relationship in a South American, Chaco ant community. 3 The activity and behaviour of ground-foraging, omnivorous ants were examined at baits in open and closed, forested habitats during different seasons and times of day to characterize the responses of ant taxa to variation in microclimate and competitors. 4. Behaviourally dominant ants were most active at moderately high temperatures, whereas subordinate species were active at extreme temperatures, when they had virtually exclusive access to resources. 5. The patterns presented here and those observed in other studies suggest that there is a general trade-off between behavioural dominance and thermal tolerance in ants. This trade-off creates a linear relationship between temperature use and dominance for ants up to ≈ 35 °C, but extremely high temperatures may also be stressful such that the full relationship is actually unimodal.

Authors

Bestelmeyer, Brandon T.

Year Published

2000

Publication

Journal of Animal Ecology

Locations
DOI

10.1111/j.1365-2656.2000.00455.x

Recent Articles

Beyond the Least-Cost Path: Evaluating Corridor Redundancy Using a Graph-Theoretic Approach

by Pinto, Naiara and Keitt, Timothy H.

The impact of the landscape matrix on patterns of animal movement and population dynamics has been widely recognized by ecologists. However, few tools are available to model the matrix’s influence on the length, relative quality, and redundancy of dispersal routes connecting habitat patches. Many GIS software packages can use land use/land cover maps to identify the route of least resistance be...

published 2009 in Landscape Ecology

Effects of Urban Development on Ant Communities: Implications for Ecosystem Services and Management

by SANFORD, MONTE P., MANLEY, PATRICIA N. and MURPHY, DENNIS D.

Research that connects the effects of urbanization on biodiversity and ecosystem services is lacking. Ants perform multifarious ecological functions that stabilize ecosystems and contribute to a number of ecosystem services. We studied responses of ant communities to urbanization in the Lake Tahoe basin by sampling sites along a gradient of urban land development. We sampled ant communities, me...

published 2009 in Conservation Biology


Impact of Flooding on the Species Richness, Density and Composition of Amazonian Litter-Nesting Ants

by Mertl, Amy L., Ryder Wilkie, Kari T. and Traniello, James F. A.

Litter-nesting ants are diverse and abundant in tropical forests, but the factors structuring their communities are poorly known. Here we present results of the first study to examine the impact of natural variation in flooding on a highly diverse (21 genera, 77 species) litter-nesting ant community in a primary Amazonian forest. Fifty-six 3 × 3 m plots experiencing strong variation in flooding...

published 2009 in Biotropica

Species Richness, Equitability, and Abundance of Ants in Disturbed Landscapes

by Graham, John H., Krzysik, Anthony J., Kovacic, David A., Duda, Jeffrey J., Freeman, D. Carl, Emlen, John M., Zak, John C., Long, W. Russell, Wallace, Michael P., Chamberlin-Graham, Catherine, Nutter, Jonathan P. and Balbach, Hal E.

Ants are used as indicators of environmental change in disturbed landscapes, often without adequate understanding of their response to disturbance. Ant communities in the southeastern United States displayed a hump-backed species richness curve against an index of landscape disturbance. Forty sites at Fort Benning, in west-central Georgia, covered a spectrum of habitat disturbance (military tra...

published 2009 in Ecological Indicators