Search results for "Habit"
showing 10 items of 1816 documents
Resistance of seagrass habitats to ocean acidification via altered interactions in a tri-trophic chain
2020
Despite the wide knowledge about prevalent effects of ocean acidification on single species, the consequences on species interactions that may promote or prevent habitat shifts are still poorly understood. Using natural CO2 vents, we investigated changes in a key tri-trophic chain embedded within all its natural complexity in seagrass systems. We found that seagrass habitats remain stable at vents despite the changes in their tri-trophic components. Under high pCO2, the feeding of a key herbivore (sea urchin) on a less palatable seagrass and its associated epiphytes decreased, whereas the feeding on higher-palatable green algae increased. We also observed a doubled density of a predatory wr…
Assessing the importance of nursery areas of European hake (Merluccius merluccius) using a body condition index
2017
Abstract In this study, we analysed the variability of reserve storage in juvenile European hake (Merluccius merluccius) off the western coasts of Italy (Central Mediterranean Sea). Reserve storage was measured by the hepatosomatic index (HSI), in relation to environmental and population covariates. HSI has been proved to be a consistent measure of energy storage in gadoids, thus reflecting quantity and quality of food availability for growth. Generalized Additive Models for Location, Scale and Shape (GAMLSS) were used to model the effect of depth, bottom temperature, bottom currents, fish density and fish body size on HSI of juvenile European hake. The results revealed that reserve storage…
Climate change exacerbates interspecific interactions in sympatric coastal fishes
2012
Summary 1. Biological responses to warming are presently based on the assumption that species will remain within their bioclimatic envelope as environmental conditions change. As a result, changes in the relative abundance of several marine species have been documented over the last decades. This suggests that warming may drive novel interspecific interactions to occur (i.e. invasive vs. native species) or may intensify the strength of pre-existing ones (i.e. warm vs. cold adapted). For mobile species, habitat relocation is a viable solution to track tolerable conditions and reduce competitive costs, resulting in ‘winner’ species dominating the best quality habitat at the expense of ‘loser’…
Notes on a small collection of phaneropterine bush-crickets (Insecta: Orthoptera: Tettigonioidea) from Central and Southern Madagascar with the descr…
2019
During a joint ecological project of the Institute of Forest Ecology, Slovak Academy of Sciences, Zvolen, Slovakia, and the University of Antananarivo, Madagascar, eight species (10 specimens) of phaneropterine bush-crickets were collected. Among them, two species were found as new to science (Mimoscudderia longicaudata n. sp., Paraphyrrhicia leuca n. sp.) and are described in this paper. Two other species (Plangia segonoides, Trigonocorypha maxima) were found the first time after their description more than 100 years ago. We provide first detailed data about their localities and habitat.
Intégrer la connectivité paysagère dans la séquence ERC : une approche par la quantité d'habitat atteignable
2019
Des engagements nationaux, européens et internationaux ont été pris pour maintenir et restaurer la connectivité entre habitats naturels face à la perte et à la fragmentation de ces habitats. Dans le même temps, les politiques environnementales dans différents pays mettent en oeuvre la séquence Eviter-Réduire-Compenser (ERC) pour atteindre l’objectif d’absence de perte nette de biodiversité (PPN). La séquence ERC a pour principe d’évaluer l’ensemble des impacts écologiques d’un aménagement, mais les critères et indicateurs permettant de quantifier les impacts sur la connectivité paysagère ne sont pas satisfaisants. Nous proposons une démarche opérationnelle pour évaluer les impacts environne…
The relevance of urban agroforestry and urban remnant forest for avian diversity in a densely-populated developing country: the case of Port-au-Princ…
2021
9 pages; International audience; Urban green spaces can contribute to conserve some of the original avian diversity in urbanized landscapes. However, the relative contribution of urban agriculture vs. urban forest remnants to the preservation of the avifauna in large cities, particularly in developing countries in the tropics, remains poorly documented. We assessed bird assemblages in the densely-populated capital city of Port-au-Prince in Haiti, one of the poorest countries in the world. From early January to late April 2018, 10 censuses per site were conducted in 16 urban green sites, consisting of 8 unexploited, private forest patches and 8 agroforestry plantations, embedded within the u…
Landscape-scale simulation experiments test Romanian and Swiss management guidelines for mountain pasture-woodland habitat diversity
2016
Distinct guidelines have been proposed in Romania and Switzerland for the management of pasture woodlands that either focused on the regulation of grazing pressure (Romanian production perspective) or overall tree cover (Swiss conservation perspective). However, the landscape structural diversity and the cover of forest-grassland ecotones, which are both crucial for nature conservation value, were not explicitly considered. We aimed to compare the country-specific management guidelines regarding their efficiency for the conservation of the structurally diverse forest-grassland mosaics in the light of recent land-use and climate change. In strategic simulation experiments using the process-b…
Non-consumptive effects between predators depend on the foraging mode of intraguild prey.
2020
Predator non-consumptive effects (NCE) are a suite of phenotypic responses of prey to avoid predation that cascade down food webs and can have a stronger impact than predation itself. However, the role of NCE in intraguild interactions remains understudied. Thus, multi-species experiments based on species traits are needed to improve our understanding of the impact of NCE on community structure. We investigated NCE of ants on 17 spider species as intraguild prey (8 cursorial and 9 sedentary) to test the influence of spider hunting mode on the strength of NCE. Sedentary spiders select a habitat patch and wait for prey, whereas cursorial spiders roam around searching for prey. Because activel…
Stable coexistence of genetically divergent Atlantic cod ecotypes at multiple spatial scales
2018
Abstract Coexistence in the same habitat of closely related yet genetically different populations is a phenomenon that challenges our understanding of local population structure and adaptation. Identifying the underlying mechanisms for such coexistence can yield new insight into adaptive evolution, diversification and the potential for organisms to adapt and persist in response to a changing environment. Recent studies have documented cryptic, sympatric populations of Atlantic cod (Gadus morhua) in coastal areas. We analysed genetic origin of 6,483 individual cod sampled annually over 14 years from 125 locations along the Norwegian Skagerrak coast and document stable coexistence of two gene…
Effects of a mobile disturbance pattern on dynamic patch networks and metapopulation persistence
2021
Abstract Motivation Certain early-succession habitats may emerge only at restricted locations following disturbance. Therefore, whether disturbances tend to occur at certain sites or not can significantly affect habitat availability and metapopulation persistence of early-successional habitat specialists. Available models that combine metapopulation and landscape processes do not address how to model mobile, spatially shifting disturbance intensities independent of factors of site suitability. We present a model that allows the study on how a mobile disturbance pattern, of either natural or anthropogenic origin, affects patch network and metapopulation dynamics in realistic, heterogeneous l…