scholarly journals May sympatric Lesser Spotted Eagles and Black Storks compete for nesting sites in spatially varying environments?

2019 ◽  
Vol 25 (1) ◽  
pp. 63-68
Author(s):  
Saulis Skuja ◽  
Gintautas Mozgeris ◽  
Rimgaudas Treinys
Keyword(s):  
Environmental Heterogeneity ◽  
Biotic Interactions ◽  
Niche Overlap ◽  
Sympatric Species ◽  
Mature Forest ◽  
Habitat Differences ◽  
Nesting Sites ◽  
Habitat Differentiation ◽  
Black Stork ◽  
Central Eastern

Sympatric species are likely to compete with one another unless there is a low degree of overlap in their resource use, in which case these species are able to coexist. Disclosing of biotic interactions between sympatric species is important from both theoretical and practical perspectives, especially when the species are of conservation concern.  However, environmental heterogeneity may introduce variation in the intensity of biotic interactions due to differential a varying species responses to the environmental gradient. In this study, we analysed the overlap in nesting sites between the internationally protected, mature, forest-dwelling Lesser Spotted Eagle Clanga pomarina and the Black Stork Ciconia nigra. The importance of landscape heterogeneity for habitat segregation between these species was also assessed. The nesting sites of 123 pairs of Lesser Spotted Eagles and 78 pairs of Black Storks, located across different landscapes of the Central, Central-Eastern and Eastern Lithuanian ecoregions were described. A series of discriminant analyses were performed to explore the pattern of habitat differentiation between species nesting in the above-mentioned regions. The habitat differentiation was estimated by niche overlap values (range 0-1, with a value 0.6 suggested to be the threshold between coexistence and competition). Comparison of nesting sites of mature forest-dwellers resulted in the niche overlap values for Central, Central-Eastern and Eastern regions being 0.5, 0.63 and 0.55, respectively. These results indicated relatively high niche overdispersion between nesting sites occupied by eagles and storks. Different variables and/or their combinations resulted in habitat differences in each ecoregion. Our data indicate that biotic interaction between species is mediated by environmental heterogeneity. Although our data tend to support the coexistence of the Black Stork and the Lesser Spotted Eagle, in certain regions these mature, forest-dwelling predators may use similar habitats and compete for prime sites under specific landscape structures. We, therefore, propose the necessity of the importance of a spatially-segregated estimation on biotic interactions when developing conservation programmes and allocating conservation actions within the target region.

NEST SITE SELECTION BY BUMBLE BEES (HYMENOPTERA: APIDAE) IN SOUTHERN ALBERTA

1978 ◽  
Vol 110 (3) ◽  
pp. 301-318 ◽  
Author(s):  
K. W. Richards
Keyword(s):  
Site Selection ◽  
Nest Site ◽  
Niche Overlap ◽  
Nest Site Selection ◽  
Bumble Bees ◽  
Social Parasites ◽  
Southern Alberta ◽  
Nesting Sites ◽  
Coexisting Species ◽  
Nesting Preferences

AbstractThe niche breadth and overlap in nesting preferences of 15 species of bumble bees were investigated in Alberta. Some of the factors that influence the distribution of nesting sites and abundance of species and permit the species to coexist in sympatry are discussed. Artificial domiciles were used as potential nesting sites. Some species were specialists in terms of nest site selection while others were generalists. The few natural nests found, the long periods spent by queens searching for nests, the high frequency of usurpation or direct interference and death of intruders, and the frequency of high niche overlap values between species are evidence that nesting sites are limited and are incompletely partitioned among the coexisting species. Usurpation also demonstrates the competition among individuals and species. Phenological differences in nest establishment influence the competition among the species. Camouflaging of tunnels presumably reduces the intensity of usurpation and protects queens and the brood from inclement weather and from social parasites (e.g., Psithyrus) and predators.

scholarly journals Breeding population of Black Stork, Ciconia nigra, in Italy between 1994 and 2016

2018 ◽  
Vol 88 (1) ◽  
pp. 15-22 ◽  
Author(s):  
Maurizio Fraissinet ◽  
Lucio Bordignon ◽  
Massimo Brunelli ◽  
Matteo Caldarella ◽  
Enzo Cripezzi ◽  
...  
Keyword(s):  
Population Density ◽  
Breeding Population ◽  
Breeding Period ◽  
High Increase ◽  
Nesting Sites ◽  
Central Regions ◽  
Southern Central ◽  
Ciconia Nigra ◽  
Black Stork ◽  
Piedmont Region

The Black Stork Ciconia nigra, following an expansion on European scale, started breeding in Italy in 1994 with one pair in the Piedmont Region and one in the Calabria Region. Since then, the breeding pairs established in Italy have progressively increased up to 18 in 2016, and they are currently in Piedmont, Lazio, Campania, Molise, Apulia, Basilicata and Calabria. However, the number of breeding pairs could be higher than 20, as indicated by records and observations of adults and juveniles, during the breeding period in potentially suitable nesting areas. Despite the low population density in Italy, the trend in the breeding population in Northwest and in Southern Central regions seems to show a slight and high increase respectively. Productivity, breeding success and fledging rate have been considered and analysed. A difference between the two macro areas has been found in the choice of nesting sites, which is on trees for Northwest couples, and cliffs for Southern Central couples. It is necessary to further explore the reason why the small Northwest population does not show any increase and range expansion compared to the Southern Central one.

scholarly journals The proportion of core species in a community varies with spatial scale and environmental heterogeneity

2018 ◽  
Author(s):  
Molly F Jenkins ◽  
Ethan P White ◽  
Allen H Hurlbert
Keyword(s):  
Spatial Scale ◽  
Environmental Heterogeneity ◽  
Biotic Interactions ◽  
Bird Community ◽  
Species Variation ◽  
Ecological Communities ◽  
Transient Species ◽  
Ecological Processes ◽  
Core Species ◽  
Wide Range

Ecological communities are composed of a combination of core species that maintain local viable populations and transient species that occur infrequently due to dispersal from surrounding regions. Preliminary work indicates that while core and transient species are both commonly observed in community surveys of a wide range of taxonomic groups, their relative prevalence varies substantially from one community to another depending upon the spatial scale at which the community was characterized and its environmental context. We used a geographically extensive dataset of 968 bird community time series to quantitatively describe how the proportion of core species in a community varies with spatial scale and environmental heterogeneity. We found that the proportion of core species in an assemblage increased with spatial scale in a positive decelerating fashion with a concomitant decrease in the proportion of transient species. Variation in the shape of this scaling relationship between sites was related to regional environmental heterogeneity, with lower proportions of core species at a given scale associated with high environmental heterogeneity. This influence of scale and environmental heterogeneity on the proportion of core species may help resolve discrepancies between studies of biotic interactions, resource availability, and mass effects conducted at different scales, because the importance of these and other ecological processes are expected to differ substantially between core and transient species.

Biotic interactions affect fitness across latitudes, but only drive local adaptation in the tropics

2019 ◽  
Author(s):  
Anna L. Hargreaves ◽  
Rachel M. Germain ◽  
Megan Bontrager ◽  
Joshua Persi ◽  
Amy L. Angert
Keyword(s):  
Local Adaptation ◽  
Environmental Heterogeneity ◽  
Meta Analysis ◽  
Biotic Interactions ◽  
Common Garden ◽  
Spatiotemporal Scales ◽  
Common Garden Experiments ◽  
Experimental Treatments ◽  
The Tropics ◽  
Biotic Environment

AbstractLocal adaptation to broad-scale environmental heterogeneity can increase species’ distributions and diversification, but which environmental components commonly drive local adaptation— particularly the importance of biotic interactions—is unclear. Biotic interactions should drive local adaptation when they impose consistent divergent selection; if this is common we expect experiments to detect more frequent and stronger local adaptation when biotic interactions are left intact. We tested this hypothesis using a meta-analysis of common-garden experiments from 138 studies (149 taxa). Across studies, local adaptation was common and biotic interactions affected fitness. Nevertheless, local adaptation was neither more common nor stronger when biotic interactions were left intact, either between experimental treatments within studies (control vs. biotic interactions experimentally manipulated) or between studies that used natural vs. biotically-altered transplant environments. However, tropical studies, which comprised only 7% of our data, found strong local adaptation in intact environments but not when negative biotic interactions were ameliorated, suggesting that interactions frequently drive local adaptation in the tropics. Our results suggest that biotic interactions often fail to drive local adaptation even though they affect fitness, perhaps because the temperate-zone biotic environment is less predictable at the spatiotemporal scales required for local adaptation.

Niche overlap and sett-site resource partitioning for two sympatric species of badger

2009 ◽  
Vol 21 (2) ◽  
pp. 89-100 ◽  
Author(s):  
L. Zhang ◽  
Y.-B. Zhou ◽  
C. Newman ◽  
Y. Kaneko ◽  
D.W. Macdonald ◽  
...  
Keyword(s):  
Resource Partitioning ◽  
Niche Overlap ◽  
Sympatric Species

Comparative Aspects of Diet and Habitat in some New Caledonian Lizards

1987 ◽  
Vol 8 (4) ◽  
pp. 349-364 ◽  
Author(s):  
Aaron M. Bauer ◽  
Kathleen D. De Vaney
Keyword(s):  
New Caledonia ◽  
Activity Patterns ◽  
Sympatric Species ◽  
Diel Activity ◽  
Large Prey ◽  
Habitat Differences ◽  
Diel Activity Patterns ◽  
Important Food Source ◽  
Two Parameters ◽  
Eleven Species

AbstractNo comparative ecological studies have previously been conducted on the lizards of New Caledonia. This study examines two parameters of resource partitioning-diet and microhabitat, for eleven species of native lizards (Gekkonidae and Scincidae). Differences in diel activity patterns and coarse habitat differences tend to segregate geckos from skinks. Microhabitat and dietary differences were found among four sympatric species in a forest assemblage at Mt. Koyaboa, but retreat sites and some food resources were employed by all. Rock piles and crevices are important retreats for all the forest species studied and are a crude predictor of lizard abundance. Crickets and terrestrial isopods are the most important items in the diet of the predominant gecko Bavayia sauvagii. Though generally considered arboreal, this lizard is frequently active on the ground as well. Ants are an important food source of the forest skink Leiolopisma tricolor, whereas the ubiquitous ground skink Leiolopisma austrocaledonicum eats a wide variety of prey, with smaller individuals selectively taking smaller prey. Larger individuals consume feew large prey items but these may be of great energetic importance.

scholarly journals Phylogenetic relatedness as a tool in restoration ecology: a meta-analysis

2011 ◽  
Vol 279 (1734) ◽  
pp. 1761-1767 ◽  
Author(s):  
Miguel Verdú ◽  
Lorena Gómez-Aparicio ◽  
Alfonso Valiente-Banuet
Keyword(s):  
Restoration Ecology ◽  
Life Form ◽  
Meta Analysis ◽  
Biotic Interactions ◽  
General Rule ◽  
Niche Overlap ◽  
Life Forms ◽  
Phylogenetic Distance ◽  
Phylogenetic Relatedness ◽  
Ecological Requirements

Biotic interactions assembling plant communities can be positive (facilitation) or negative (competition) and operate simultaneously. Facilitative interactions and posterior competition are among the mechanisms triggering succession, thus representing a good scenario for ecological restoration. As distantly related species tend to have different phenotypes, and therefore different ecological requirements, they can coexist, maximizing facilitation and minimizing competition. We suggest including phylogenetic relatedness together with phenotypic information as a predictor for the net effects of the balance between facilitation and competition in nurse-based restoration experiments. We quantify, by means of a Bayesian meta-analysis of nurse-based restoration experiments performed worldwide, the importance of phylogenetic relatedness and life-form disparity in the survival, growth and density of facilitated plants. We find that the more similar the life forms of neighbouring plants are the greater the positive effect of phylogenetic distance is on survival and density. This result suggests that other characteristics beyond life form are also contained in the phylogeny, and the larger the phylogenetic distance, the less is the niche overlap, and therefore the less is the competition. As a general rule, we can maximize the success of the nurse-based practices by increasing life-form disparity and phylogenetic distances between the neighbour and the facilitated plant.

scholarly journals American martens use vigilance and short-term avoidance to navigate a landscape of fear from fishers at artificial scavenging sites

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Todd M. Kautz ◽  
Dean E. Beyer ◽  
Zachary Farley ◽  
Nicholas L. Fowler ◽  
Kenneth F. Kellner ◽  
...  
Keyword(s):  
Interference Competition ◽  
Niche Overlap ◽  
Sympatric Species ◽  
Diel Activity ◽  
Short Term ◽  
Landscape Of Fear ◽  
Remote Cameras ◽  
Pekania Pennanti ◽  
Carnivore Species ◽  
American Martens

AbstractWhere two sympatric species compete for the same resource and one species is dominant, there is potential for the subordinate species to be affected through interference competition or energetic costs of avoiding predation. Fishers (Pekania pennanti) and American martens (Martes americana) often have high niche overlap, but fishers are considered dominant and potentially limiting to martens. We observed presence and vigilance of fishers and martens at winter carcass sites using remote cameras in Michigan, USA, to test the hypothesis that interference competition from fishers creates a landscape of fear for martens. Within winters, fishers co-occupied 78–88% of sites occupied by martens, and martens co-occupied 79–88% of sites occupied by fishers. Fishers displaced martens from carcasses during 21 of 6117 marten visits, while martens displaced fishers during 0 of 1359 fisher visits. Martens did not alter diel activity in response to fisher use of sites. Martens allocated 37% of time to vigilance compared to 23% for fishers, and martens increased vigilance up to 8% at sites previously visited by fishers. Fishers increased vigilance by up to 8% at sites previously visited by martens. Our results indicate that fishers were dominant over martens, and martens had greater baseline perception of risk than fishers. However, fishers appeared to be also affected as the dominant competitor by putting effort into scanning for martens. Both species appeared widespread and common in our study area, but there was no evidence that fishers spatially or temporally excluded martens from scavenging at carcasses other than occasional short-term displacement when a fisher was present. Instead, martens appeared to mitigate risk from fishers by using vigilance and short-term avoidance. Multiple short-term anti-predator behaviors within a landscape of fear may facilitate coexistence among carnivore species.

Sign in / Sign up

Export Citation Format

Share Document