scholarly journals Behavioural Plasticity by Eastern Grey Kangaroos in Response to Human Behaviour

Animals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 244 ◽  
Author(s):  
Caitlin M. Austin ◽  
Daniel Ramp
Keyword(s):  
Spatial Scales ◽  
Single Species ◽  
Behavioural Response ◽  
Behavioural Plasticity ◽  
Single Population ◽  
Human Disturbances ◽  
High Frequencies ◽  
Human Presence ◽  
Antipredator Strategy ◽  
Harmful Effects

Sharing landscapes with humans is an increasingly fraught challenge for wildlife across the globe. While some species benefit from humans by exploiting novel opportunities (e.g., provision of resources or removal of competitors or predators), many wildlife experience harmful effects, either directly through persecution or indirectly through loss of habitat. Consequently, some species have been shown to be attracted to human presence while others avoid us. For any given population of a single species, though, the question of whether they can recognise and change their response to human presence depending on the type of human actions (i.e., either positive or negative) has received little attention to date. In this study, we chose to examine the behavioural plasticity within a single population of eastern grey kangaroos (Macropus giganteus) to both positive and negative human activity. Within a relatively small and contiguous landscape, we identified areas where kangaroos experience a combination of either low and high frequencies of benign and harmful human disturbances. From six sampling sessions over five months, we found that density and group sizes were higher where humans acted benignly towards them, and that these groups had higher representations of sub-adults and juveniles than where humans had harmful intentions. Importantly, we found that the vital antipredator strategy of increasing group size with distance from cover was not detectable at sites with low and high levels of harm. Our findings suggest that these kangaroos are recognising and adjusting their behavioural response to humans at fine spatial scales, a plasticity trait that may be key to the survival of these species in human dominated landscapes.

scholarly journals Occurrence and Activity of Roe Deer in Urban Forests of Warsaw

2020 ◽  
Vol 3 (1) ◽  
pp. 35
Author(s):  
Karolina D. Jasińska ◽  
Mateusz Jackowiak ◽  
Jakub Gryz ◽  
Szymon Bijak ◽  
Katarzyna Szyc ◽  
...  
Keyword(s):  
Predation Risk ◽  
Urban Area ◽  
Roe Deer ◽  
Urban Forests ◽  
Anthropogenic Disturbances ◽  
Camera Traps ◽  
Human Disturbances ◽  
Human Presence ◽  
Big Cities ◽  
High Level

Human presence or activities are perceived by animals as those associated with predation risk so activity and exploration patterns of animals should be shaped by indices of anthropogenic disturbances. The high level of human disturbances is noticed in big cities. Therefore, the aim of the study was to determine the occurrence of roe deer in Warsaw and its activity in the Warsaw urban forests. We used snow tracking on transect routes (winter seasons 2016, 2017, 2018; 115.1 km in total) to determine roe deer occurrence in four habitats: forests, open areas, parks, and built-up areas. The number of tracks was highest in forests (4.6 tracks/1 km/24 h), followed by open areas, built-up areas, and parks. We used camera traps to determine the activity of roe deer in selected urban forests. We collected 697 observations of roe deer in Warsaw forests in the years 2016–2019 (per 4826 trap-days in total). The peak of roe deer activity was noticed between 4:00 and 5:00 a.m. Animals were least active at 1:00–2:00 p.m. and between 11:00 p.m.–01:00 a.m. Our research showed that roe deer inhabiting the urban area avoided human presence by using well-covered habitats and being active in periods when humans’ disturbances’ level is lower.

scholarly journals Connecting mercury science to policy: from sources to seafood

2016 ◽  
Vol 31 (1) ◽  
Author(s):  
Celia Y. Chen ◽  
Charles T. Driscoll ◽  
Kathleen F. Lambert ◽  
Robert P. Mason ◽  
Elsie M. Sunderland
Keyword(s):  
Spatial Scales ◽  
Organizational Level ◽  
Past Century ◽  
International Policy ◽  
Ecosystem Research ◽  
Surface Ocean ◽  
The Past ◽  
Harmful Effects ◽  
Binding Agreement ◽  
Hg Pollution

AbstractMercury (Hg) is a global contaminant whose presence in the biosphere has been increased by human activity, particularly coal burning/energy production, mining, especially artisanal scale gold mining, and other industrial activities. Mercury input to the surface ocean has doubled over the past century leading governments and organizations to take actions to protect humans from the harmful effects of this toxic element. Recently, the UN Environmental Program led 128 countries to negotiate and sign a legally binding agreement, the 2013 Minimata Convention, to control Hg emissions and releases to land and water globally. In an effort to communicate science to this emerging international policy, the Dartmouth Superfund Research Program formed the Coastal and Marine Mercury Ecosystem Research Collaborative (C-MERC) in 2010 that brought together more than 70 scientists and policy experts to analyze and synthesize the science on Hg pollution in the marine environment from Hg sources to MeHg in seafood. The synthesis of the science revealed that the sources and inputs of Hg and their pathways to human exposure are largely determined by ecosystem spatial scales and that these spatial scales determine the organizational level of policies. The paper summarizes the four major findings of the report.

scholarly journals Species-area relationships emerge from multiple coexistence mechanisms

2021 ◽  
Author(s):  
David Garcia-Callejas ◽  
Ignasi Bartomeus ◽  
Oscar Godoy
Keyword(s):  
Species Richness ◽  
Spatial Heterogeneity ◽  
Species Interactions ◽  
Spatial Scales ◽  
Single Species ◽  
Small Population ◽  
Collective Effects ◽  
Demographic Stochasticity ◽  
Species Dominance ◽  
Species Area

The increase of species richness with area is a universal phenomenon on Earth. However, this observation contrasts with our poor understanding of how these species-area relationships (SARs) emerge from the collective effects of area, spatial heterogeneity, and local interactions. By combining a structuralist approach with five years of empirical observations in a highly-diverse grassland, we show that,contrary to expectations, spatial heterogeneity plays a little role in the accumulation of species richness with area in our system. Instead, as we increase the sampled area more species combinations are realized, and they coexist mainly due to direct pairwise interactions rather than by changes in single-species dominance or by indirect interactions. We also identify a small set of transient species with small population sizes that are consistently found across spatial scales. These findings empirically support the importance of the architecture of species interactions together with demographic stochasticity for driving SARs.

scholarly journals Habitat use by semi-domesticated reindeer, estimated with pellet-group counts

Rangifer ◽  
2009 ◽  
Vol 27 (2) ◽  
pp. 121 ◽  
Author(s):  
Anna Skarin
Keyword(s):  
Habitat Selection ◽  
Habitat Use ◽  
Rangifer Tarandus ◽  
Spatial Scales ◽  
Abiotic Factors ◽  
Resource Utilisation ◽  
High Quality ◽  
Human Disturbances ◽  
Pellet Group ◽  
Rangifer Tarandus Tarandus

Habitat selection theory predicts that herbivores should select for or against different factors at different spatial scales. For instance, quantity of forage is expected to be a strong factor influencing habitat choice at large scales, while forage quality may be important at finer scales. However, during summer, herbivores such as reindeer (Rangifer tarandus tarandus) can be limited in their grazing time by insect harassment, and do not always have the possibility to select for high quality forage. Human disturbances from hikers, etc., can also have a limiting effect on the possibility for reindeer to graze in high quality foraging habitats. Reindeer habitat selection at the landscape level was investigated through faecal pellet-group counts during the summers of 2002 and 2003 in two reindeer herding districts in Sweden. Resource utilization functions (RUFs) were developed using multiple linear regressions, where the pellet densities were related to vegetation types, topographic features, distances to tourist resorts, and distances to hiking trails. Validations of the models were performed through cross-validation correlations. Results show that high altitudes with high quality forage were important habitats. Areas that offer both snow patches and fresh forage plants for the reindeer were used in relation to their availability. The reindeer also seemed able to habituate to human intervention to a certain extent. The predictive capabilities of the RUF models were high and pellet-group counts seemed well suited to study how abiotic factors affect the habitat use at large temporal and spatial scales Abstract in Swedish / Sammanfattning: Renens användning av sommarbetesområdet, uppskattat med spillningsinventeringar Hierarkiskt habitatval innebär att djur väljer för och emot olika faktorer beroende på den rumsliga skalan. Mängden bete kan t ex spela stor roll för en växtätares habitatval på en stor skala medan kvalitén på betet kan ha större betydelse på en mindre skala. För renar (Rangifer tarandus tarandus), kan betestiden och möjligheten att hitta bra bete sommartid begränsas både på stor och liten skala pga. störningar från insekter och mänsklig aktivitet. Här studerades renarnas val av betesområde på landskapsnivå med hjälp av spillningsinventering under somrarna 2002 och 2003 i två samebyar i Sverige. Spillningstätheten för respektive område och år undersöktes statistiskt med hjälp av multipel linjär regression eller sk ”resource utilisation functions” (RUF). Där relaterades spillningstätheten till vegetationstyp, olika topografiska faktorer, avstånd till vandringsleder, stugplatser och fjällstationer. Resultaten visade att områden högt upp i terrängen med hög beteskvalitet var attraktiva. Vegetationstypen moderat snölega som anses ha hög beteskvalitet användes av renarna i relation till dess förekomst. Däremot verkade renarna undvika områden kring välbesökta fjällstugor och fjällstationer medan de däremot t o m föredrog områden nära vandringsleder. Det kan bero på att vandringslederna går genom attraktiva vegetationstyper. RUF-modellerna hade en hög prediktiv förmåga vilket visar att spillningsinventeringar är användbara när man önskar studera hur djuren använder ett betesområde i relation till olika faktorer på en relativt stor rumslig och temporal skala.

scholarly journals Predictor species: Improving assessments of rare species occurrence by modelling environmental co-responses

2019 ◽  
Author(s):  
Peter R. Thompson ◽  
William F. Fagan ◽  
Phillip P.A. Staniczenko
Keyword(s):  
Rare Species ◽  
Spatial Scales ◽  
Single Species ◽  
Conservation Strategy ◽  
Individual Species ◽  
Calibration Data ◽  
Distribution Models ◽  
New Approach ◽  
Effective Conservation ◽  
Better Than

ABSTRACTDesigning an effective conservation strategy requires understanding where rare species are located. Although species distribution models are primarily used to identify patterns at large spatial scales, their general methodology is relevant for predicting the occurrence of individual species at specific locations. Here we present a new approach that uses Bayesian networks to improve predictions by modelling environmental co-responses among species. For species from a European peat bog community, our approach consistently performs better than single-species models, and better than conventional multi-species models for rare species when calibration data are limited. Furthermore, we identify a group of “predictor species” that are relatively common, insensitive to the presence of other species, and can be used to improve occurrence predictions of rare species. Predictor species are distinct from other categories of conservation surrogates such as umbrella or indicator species, which motivates focused data collection of predictor species to enhance conservation practices.

An Adaptive Genetic Algorithm Based on Multi-Population Parallel Evolutionary for Highway Alignment Optimization Model

2011 ◽  
Vol 58-60 ◽  
pp. 1499-1503 ◽  
Author(s):  
Jian Xin Chen ◽  
Yong Yi Guo ◽  
Mai Xia Lv
Keyword(s):  
Genetic Algorithm ◽  
Convergence Rate ◽  
Single Species ◽  
Adaptive Genetic Algorithm ◽  
Parallel Genetic Algorithm ◽  
Single Population ◽  
Highway Design ◽  
Population Evolution ◽  
Highway Alignment Optimization ◽  
Highway Alignment

Based on the characteristics of the highway design, this paper transfers all the factors involved in the highway design to a cost-optimized-oriented model and designs a variety parallel genetic algorithm to optimize highway design. While maintaining evolution stability of excellent individual, the algorithm can improve convergence rate and accuracy and avoid premature convergence generated by single-population evolution. To some extent, it makes up generalization-lacking defects of a single species or steady parameters in premature overcoming. Finally, the algorithm is verified with a good result. This algorithm provides a useful method for highway design.

Spatial variability and human disturbance of sponge assemblages associated with mangrove roots in the southern Caribbean

2011 ◽  
Vol 62 (5) ◽  
pp. 491 ◽  
Author(s):  
Edlin Guerra-Castro ◽  
Paula Young ◽  
Adriana Pérez-Vázquez ◽  
Sophie Carteron ◽  
Adriana Alvizu
Keyword(s):  
Spatial Variability ◽  
Human Disturbance ◽  
Spatial Scales ◽  
Caribbean Region ◽  
Small Scale ◽  
Ecological Processes ◽  
Human Disturbances ◽  
Β Diversity ◽  
Southern Caribbean ◽  
Mangrove Roots

Assemblages growing on Caribbean red-mangrove roots are very diverse and characteristically dominated by sponges. The scales of spatial variation of this fauna in the Caribbean region have not been hierarchically quantified, although such information is necessary to understand the relative importance of ecological processes and possible responses to anthropogenic disturbances. We used a hierarchical nested design to identify patterns of spatial variability at different scales, namely among roots, sites, localities and regions within the southern Caribbean. Simultaneously, the sampling considered the relative distance from sources of human disturbance to test the null hypothesis of no difference in sponge diversity among localities as a result of anthropogenic stress. Significant spatial variability in species composition was detected at all spatial scales, especially at the among-root scale. However, there were no differences associated with distance from human disturbance. These results indicate high regional and local β diversity, and also suggest that results from small-scale experiments cannot be scaled up to the entire community. Further, spatial analysis of sponge assemblages is not enough to detect deleterious effects of human disturbances on mangrove areas.

Connectivity in rivers

2017 ◽  
Vol 41 (3) ◽  
pp. 345-362 ◽  
Author(s):  
Ellen Wohl
Keyword(s):  
Spatial Scales ◽  
Nonlinear Behavior ◽  
Effective Management ◽  
Short Term ◽  
Human Disturbances ◽  
Disciplinary Boundaries ◽  
Temporal And Spatial ◽  
Fully Connected ◽  
River Corridor

Connectivity describes the degree to which matter and organisms can move among spatially defined units in a natural system. River connectivity is typically described in longitudinal, lateral, and vertical dimensions within the river corridor and the watershed and can be conceptualized as a continuum from fully connected to disconnected over diverse temporal and spatial scales. Explicit characterization of connectivity helps understanding of disparities among short-term, local rates of flux and inferred fluxes over larger scales. Connectivity also strongly influences the response of rivers to natural and human disturbances. Investigations of connectivity facilitate the recognition of processes that cross traditional disciplinary boundaries, as well as understanding of nonlinear behavior and retention within rivers. Enhancing the ability to identify, quantify, and predict the processes that create and maintain connectivity is integral to the effective management of rivers.

Responsiveness of Great Lakes Wetland Indicators to Human Disturbances at Multiple Spatial Scales: A Multi-Assemblage Assessment

2007 ◽  
Vol 33 (sp3) ◽  
pp. 42-66 ◽  
Author(s):  
John C. Brazner ◽  
Nicolas P. Danz ◽  
Anett S. Trebitz ◽  
Gerald J. Niemi ◽  
Ronald R. Regal ◽  
...  
Keyword(s):  
Great Lakes ◽  
Spatial Scales ◽  
Human Disturbances ◽  
Multiple Spatial Scales

scholarly journals Benthic macrofaunal structure and secondary production in tropical estuaries on the Eastern Marine Ecoregion of Brazil

2017 ◽  
Author(s):  
Lorena B Bissoli ◽  
Angelo F Bernardino
Keyword(s):  
Secondary Production ◽  
Human Impacts ◽  
Spatial Scales ◽  
Tidal Flats ◽  
Benthic Assemblages ◽  
Human Disturbances ◽  
Tropical Estuaries ◽  
Benthic Production ◽  
Eastern Brazil ◽  
Habitat Differences

Estuaries are highly productive and support diverse benthic assemblages, but few estimates of benthic production are available for most ecosystems. In tropical estuaries mangroves and tidal flats are typical habitats with high spatial heterogeneity of benthic macrofaunal assemblages. However, accessing differences and similarities of benthic assemblages within estuarine habitats and between regional ecosystems may provide scientific support to management of those ecosystems. Here we studied three tropical estuaries in the Eastern Marine Ecoregion of Brazil to assess the spatial variability of benthic assemblages from vegetated (mangroves) and unvegetated (tidal flats) habitats. A nested sampling design was used to determine spatial scales of variability in benthic macrofaunal density, biomass and secondary production. Habitat differences in benthic assemblage composition, biomass, density and secondary production were significant, but also varied between estuaries. Macrofaunal secondary production differed between estuaries and between tidal flat and mangrove habitats, and those differences were related to the composition of benthic assemblages. High benthic production were associated with tidal flats in estuaries with presumable less human impacts, although benthic assemblages from mangrove sediments had similar production irrespective of human disturbances. Given variable levels of human impacts and predicted climate change effects on tropical estuarine assemblages in Eastern Brazil, our data support the use of benthic secondary production to address long-term changes and improved management of estuaries in Eastern Brazil.

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