Search results for "Habitat selection"

Nest-mediated parental care in a marine fish: Are large-scale nesting habitats selected and do these habitats respond to small-scale requirements?

2018

Fishes have evolved various reproductive strategies including mechanisms that involve parental care and demersal eggs laid into nests. Symphodus ocellatus has a seasonal reproduction period during which large, dominant males become territorial and build nests with fragments of algae, where they attract females to spawn and provide care to the developing eggs. Based on the hypothesis that the S. ocellatus males choose the reproductive habitat based on some characteristics of the substrate, here we assessed whether, on a coastal area scale, the distribution of this species changes during the reproductive period because of the selection of some suitable sites or substrates, and whether the nes…

Corynosoma cetaceum in the stomach of Franciscanas, pontoporia blainvillei (Cetacea): an exceptional case of habitat selection by an Acanthocephalan

2001

Adult acanthocephalans are typically found in the intestine of vertebrates, where they can readily absorb nutrients. However, Corynosoma cetaceum has been frequently reported in the stomach of cetaceans from the Southern Hemisphere. The ecological significance of this habitat was investigated by examining data on number, sex ratio, maturity status, biomass, and fecundity of C. cetaceum in different parts of the digestive tract of 44 franciscanas Pontoporia blainvillei. Individual C. cetaceum occurred in the pyloric stomach (PS) and, to lesser degrees, in the duodenal ampulla (DA) and the main stomach (MS). Females outnumbered males in all chambers, although the sex ratio was closer to 1:1 i…

Comparison of wormlion behavior under man-made and natural shelters: urban wormlions more strongly prefer shaded, fine-sand microhabitats, construct …

2019

Abstract Urban habitats differ from their natural surroundings in various aspects, such as a higher temperature and a distinct species composition. It is therefore not surprising that animal behavior too differs between these habitat types. We studied the foraging and habitat selection behavior of a pit-building predator, a wormlion, originating from either an urban or a more natural site. Wormlions occur in nature under structures that provide shelter from sunlight and rain, such as caves, and are also common in cities, occurring under artificial shelters. Wormlions construct pit-traps to hunt arthropods, and the pits constructed by urban wormlions were larger than those constructed by wor…

Do large‐scale associations in birds imply biotic interactions or environmental filtering?

2023

Aim There has been a wide interest in the effect of biotic interactions on species' occurrences and abundances at large spatial scales, coupled with a vast development of the statistical methods to study them. Still, evidence for whether the effects of within-trophic-level biotic interactions (e.g. competition and heterospecific attraction) are discernible beyond local scales remains inconsistent. Here, we present a novel hypothesis-testing framework based on joint dynamic species distribution models and functional trait similarity to dissect between environmental filtering and biotic interactions. Location France and Finland. Taxon Birds. Methods We estimated species-to-species association…

The Eurasian Treecreeper (Certhia familiaris) has an effective camouflage against mammalian but not avian vision in boreal forests

2022

A well-known example of visual camouflage in birds is the plumage coloration of the Eurasian Treecreeper Certhia familiaris, yet this species’ camouflage has never been objectively quantified. Here, we quantify treecreeper camouflage in its boreal forest habitat, test whether treecreepers better match tree backgrounds at nest site, territory or habitat spatial scales, and explore which common tree species provide the best background match. Using photographic data of the birds and forested backgrounds, we test their background match using human, ferret and avian vision modelling. We found that a treecreeper’s wing and mantle provided closest background matching, whereas the wing stripe and t…

Connections between microhabitat factors and dimensions of brown trout (Salmo trutta) redds

2017

This study is part of a process of habitat restoration and management of Finnish and Swedish rivers. This study was conducted to analyse detailed and generalised data regarding microhabitat factors and dimensions of spawning redd of brown trout (salmo trutta). The objectives of this study were to analyse connections between redd dimensions, connections between redd length and microhabitat factors and to analyse the variability of redd length and microhabitat factors among catchments in order to understand spawning habitat selectivity of brown trout (salmo trutta). The study shows that the redd dimensions are positively and strongly correlated. Redd length is weakly correlated to microhabita…

First estimates of density and distribution of the alien crab Percnon gibbesi (Decapoda, Percnidae) in the "Capo Gallo-Isola delle Femmine" MPA

2013

Phylogeny, epidemiology and microhabitat preferences of lungworms (Pseudaliidae) in cetaceans from teh Western Mediterranean

2023

A pesar de tener una cierta reputación negativa, los parásitos pueden ofrecer una información importante sobre sus hospedadores, habiendo sido reconocidos como herramientas valiosas en varios estudios que investigan el comportamiento (Balbuena y Raga 1991), la salud (Aznar et al. 2005; Gkafas et al. 2020), la dieta (Dailey y Otto 1982), la migración (Ten et al. 2022), la estructura social (Balbuena et al. 1995) o la discriminación de stocks de cetáceos (Aznar et al. 1995). Los helmintos que parasitan a los cetáceos se pueden separar en cuatro grupos distintos: acantocéfalos (20 spp.), cestodos (38 spp.), digeneos (54 spp.) y nematodos (62 spp.). De éstos, los nematodos son los más diversos …

Substratum recognition as settlement cue for larvae of Dendropoma cristatum (Biondi, 1859)

2017

Despite the ecological relevance of the vermetid bioconstructions in the Mediterranean, little is known about the early life stage of Dendropoma cristatum. This study describes the preference for settlement substrata from D. cristatumlarvae. A field experiment was carried out to test the suitability of crustose coralline algae (CCA), D. cristatumadults and two inorganic substrata as settlement surfaces. The number of settling larvae varied among the four treatments with higher settlement success on organic surfaces. CCA and D. cristatumindividuals seem to promote attachment of young larvae and to induce the metamorphosis in recruits. This is probably due to biological or physical properties…

Short-term occupations at high elevation during the Middle Paleolithic at Kalavan 2 (Republic of Armenia).

2021

The Armenian highlands encompasses rugged and environmentally diverse landscapes and is characterized by a mosaic of distinct ecological niches and large temperature gradients. Strong seasonal fluctuations in resource availability along topographic gradients likely prompted Pleistocene hominin groups to adapt by adjusting their mobility strategies. However, the role that elevated landscapes played in hunter-gatherer settlement systems during the Late Pleistocene (Middle Palaeolithic [MP]) remains poorly understood. At 1640 m above sea level, the MP site of Kalavan 2 (Armenia) is ideally positioned for testing hypotheses involving elevation-dependent seasonal mobility and subsistence strateg…