scholarly journals Territory characteristics and coexistence with heterospecifics in the Dartford warbler Sylvia undata across a habitat gradient

2008 ◽  
Vol 62 (8) ◽  
pp. 1217-1228 ◽  
Author(s):  
Pere Pons ◽  
Josep M. Bas ◽  
Roger Prodon ◽  
Núria Roura-Pascual ◽  
Miguel Clavero
Keyword(s):  
Habitat Gradient ◽  
Territory Characteristics

scholarly journals Widespread zoophagy and detection of Plasmodium spp. in Anopheles mosquitoes in southeastern Madagascar

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Micaela Finney ◽  
Benjamin A. McKenzie ◽  
Bernadette Rabaovola ◽  
Alice Sutcliffe ◽  
Ellen Dotson ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Vector Control ◽  
Plasmodium Vivax ◽  
Malaria Control ◽  
Feeding Behaviour ◽  
Enzyme Linked Immunosorbent Assay ◽  
Habitat Gradient ◽  
Blood Meals ◽  
Feeding Behaviours ◽  
Southeastern Madagascar

Abstract Background Malaria is a top cause of mortality on the island nation of Madagascar, where many rural communities rely on subsistence agriculture and livestock production. Understanding feeding behaviours of Anopheles in this landscape is crucial for optimizing malaria control and prevention strategies. Previous studies in southeastern Madagascar have shown that Anopheles mosquitoes are more frequently captured within 50 m of livestock. However, it remains unknown whether these mosquitoes preferentially feed on livestock. Here, mosquito blood meal sources and Plasmodium sporozoite rates were determined to evaluate patterns of feeding behaviour in Anopheles spp. and malaria transmission in southeastern Madagascar. Methods Across a habitat gradient in southeastern Madagascar 7762 female Anopheles spp. mosquitoes were collected. Of the captured mosquitoes, 492 were visibly blood fed and morphologically identifiable, and a direct enzyme-linked immunosorbent assay (ELISA) was used to test for swine, cattle, chicken, human, and dog blood among these specimens. Host species identification was confirmed for multiple blood meals using PCR along with Sanger sequencing. Additionally, 1,607 Anopheles spp. were screened for the presence of Plasmodium falciparum, P. vivax-210, and P. vivax 247 circumsporozoites (cs) by ELISA. Results Cattle and swine accounted, respectively, for 51% and 41% of all blood meals, with the remaining 8% split between domesticated animals and humans. Of the 1,607 Anopheles spp. screened for Plasmodium falciparum, Plasmodium vivax 210, and Plasmodium vivax 247 cs-protein, 45 tested positive, the most prevalent being P. vivax 247, followed by P. vivax 210 and P. falciparum. Both variants of P. vivax were observed in secondary vectors, including Anopheles squamosus/cydippis, Anopheles coustani, and unknown Anopheles spp. Furthermore, evidence of coinfection of P. falciparum and P. vivax 210 in Anopheles gambiae sensu lato (s.l.) was found. Conclusions Here, feeding behaviour of Anopheles spp. mosquitoes in southeastern Madagascar was evaluated, in a livestock rich landscape. These findings suggest largely zoophagic feeding behaviors of Anopheles spp., including An. gambiae s.l. and presence of both P. vivax and P. falciparum sporozoites in Anopheles spp. A discordance between P. vivax reports in mosquitoes and humans exists, suggesting high prevalence of P. vivax circulating in vectors in the ecosystem despite low reports of clinical vivax malaria in humans in Madagascar. Vector surveillance of P. vivax may be relevant to malaria control and elimination efforts in Madagascar. At present, the high proportion of livestock blood meals in Madagascar may play a role in buffering (zooprophylaxis) or amplifying (zoopotentiation) the impacts of malaria. With malaria vector control efforts focused on indoor feeding behaviours, complementary approaches, such as endectocide-aided vector control in livestock may be an effective strategy for malaria reduction in Madagascar.

Distribution and diet of recovering Eurasian otter (Lutra lutra) along the natural-to-urban habitat gradient (river Segura, SE Spain)

2021 ◽  
Author(s):  
Ettore Emanuele Dettori ◽  
Alessandro Balestrieri ◽  
Victor Manuel Zapata-Perez ◽  
Daniel Bruno ◽  
Nuria Rubio-Saura ◽  
...  
Keyword(s):  
Urban Habitat ◽  
Lutra Lutra ◽  
Se Spain ◽  
Eurasian Otter ◽  
Habitat Gradient

Overlap in avian communities produces unimodal richness peaks on Bornean mountains

2018 ◽  
Vol 34 (2) ◽  
pp. 75-92 ◽  
Author(s):  
Ryan C. Burner ◽  
Alison R. Styring ◽  
Chandradewana Boer ◽  
Frederick H. Sheldon
Keyword(s):  
Species Richness ◽  
Bird Species ◽  
Sufficient Evidence ◽  
Altitudinal Distribution ◽  
Bird Species Richness ◽  
Point Counts ◽  
Habitat Gradient ◽  
Quantitative Analyses ◽  
Meta Analyses ◽  
Replicated Systems

Abstract:Altitudinal gradients provide tractable, replicated systems in which to study changes in species richness and community composition over relatively short distances. Previously, richness was often assumed to follow a monotonic decline with altitude, but recent meta-analyses show that more complex patterns, including mid-altitude richness peaks, are also prevalent in birds. In this study, we used point counts to survey birds at multiple altitudes on three mountains on the island of Borneo in Sundaland, an area for which quantitative analyses of avian altitudinal distribution are unavailable. In total we conducted 1088 point counts and collected associated habitat data at 527 locations to estimate species richness by altitude on Mt Mulu (2376 m), Mt Pueh (1550 m) and Mt Topap Oso (1450 m). On Mulu, the only mountain with an intact habitat gradient, bird species richness peaks at 600 m. Richness appeared to peak at 600 m on Totap Oso as well, but on Pueh it peaked several hundred metres higher. The richness peak on Mulu differs from that predicted by null models and is instead caused by the overlap of distinct lowland and montane avifaunas, supporting the faunal overlap hypothesis. This finding provides further evidence that a lack of coincidence between peak turnover and peak richness is not sufficient evidence to rule out faunal overlap as a causal factor.

scholarly journals Singing in the suburbs: point count surveys efficiently reveal habitat associations for nocturnal Orthoptera across an urban-to-rural gradient

2020 ◽  
Vol 24 (6) ◽  
pp. 1031-1043
Author(s):  
Darin J. McNeil ◽  
Christina M. Grozinger
Keyword(s):  
Site Occupancy ◽  
Habitat Associations ◽  
Survey Method ◽  
Population Declines ◽  
Detection Rates ◽  
Point Count ◽  
Point Counts ◽  
Focal Species ◽  
Habitat Gradient ◽  
Count Surveys

Abstract As evidence for global insect population declines continues to amass, several studies have indicated that Orthoptera (grasshoppers, crickets, and katydids) are among the most threatened insect groups. Understanding Orthoptera populations across large spatial extents requires efficient survey protocols, however, many previously established methods are expensive and/or labor-intensive. One survey method widely employed in wildlife biology, the aural point count, may work well for crickets and katydids (suborder: Ensifera) because males produce conspicuous, species-specific mating calls. We conducted repeated point count surveys across an urban-to-rural gradient in central Pennsylvania. Occupancy analyses of ten focal species indicated that, although detection probability rates varied by species from 0.43 to 0.98, detection rates compounded over five visits such that all focal species achieved cumulative > 0.90. Factors associated with site occupancy varied among species with some positively associated with urbanization (e.g., Greater Anglewing, Microcentrum rhombifolium), some negatively associated with urbanization (e.g., Sword-bearing Conehead, Neoconocephalus ensiger), and others exhibiting constant occupancy across a habitat gradient (e.g., Common True Katydid, Pterophylla camellifolia). Our community-level analysis revealed that different species’ habitat associations interacted such that intermediate levels of urbanization (i.e., suburbs) hosted the highest number of species. Implications for insect conservation Ultimately, our analyses clearly support the concept that aural point counts paired with static occupancy modeling can serve as an important tool for monitoring night-singing Orthoptera populations. Applications of point count surveys by both researchers and citizen scientists may improve our understanding Ensifera populations and help in the global conservation of these threatened insects.

scholarly journals Territoriality and Neighbor Assessment in Brown Jays (Cyanocorax Morio) in Costa Rica

The Auk ◽  
2003 ◽  
Vol 120 (2) ◽  
pp. 446-456 ◽  
Author(s):  
Amanda M. Hale ◽  
Dean A. Williams ◽  
Kerry N. Rabenold
Keyword(s):  
Defense Mechanism ◽  
Affiliative Behavior ◽  
Resource Defense ◽  
Young Males ◽  
Home Group ◽  
Mating Opportunities ◽  
Intergroup Encounters ◽  
Range Overlap ◽  
Territory Characteristics ◽  
Older Males

Abstract Defense of group-held resources is a common and widely accepted function of territorial interactions between neighboring groups. In addition, territorial interactions could provide opportunities to assess members of neighboring groups and reproductive opportunities there, or to solidify status in the home group. We studied group-level characteristics and individual participation in territorial encounters in the cooperatively breeding Brown Jay (Cyanocorax morio). Intergroup encounters at stable territory boundaries include both aggressive and affiliative behavior, which suggests that a territorial encounter could function as both a resource defense mechanism and as an arena for social interactions. Territory characteristics that increase the probability of contact between groups (long boundaries, large combined group size, and home range overlap) explain much of the variation in frequency of territorial encounters. Male-biased dispersal was more common to neighboring groups with long boundaries, supporting the idea that frequent interactions between neighbors facilitate dispersal. Females usually inherit breeding positions on their natal territories, and participation in intergroup encounters by females does not vary with age or breeding status. In addition to defending group resources, females on their natal territories could be defending their positions in the breeding queue. Immigrant females are not likely to breed successfully, or to disperse again, and they participated less than expected. Participation by both natal and immigrant males varied by age; young males, at the ages when dispersal and intergroup forays are most likely, participated more than expected, whereas older males (≥4 years) participated less. That is consistent with the hypothesis that participation in intergroup encounters facilitates dispersal and improves integration into social groups. Because extragroup matings occur in this population, both breeding females and males could be assessing neighboring individuals for mating opportunities. Resource defense and social facilitation are not mutually exclusive hypotheses, and our observations suggest that both are important components of territorial encounters in Brown Jays.

Observations Upon the Sexual Behaviour of the Domestic Cat (Felis Catus L.) Under Laboratory Conditions

Behaviour ◽  
1961 ◽  
Vol 18 (1-2) ◽  
pp. 1-24 ◽  
Author(s):  
Richard P. Michael
Keyword(s):  
Sexual Behaviour ◽  
Mating Behaviour ◽  
The State ◽  
Domestic Cat ◽  
Sexual Receptivity ◽  
Ovarian Hormone ◽  
Sexual Stimulation ◽  
Behavioural Patterns ◽  
Territory Characteristics ◽  
Mating Tests

AbstractDetailed descriptions are given, based upon upwards of one thousand standardized Mating Tests, of the Patterns of Sexual Behaviour shown by the adult female cat. The changes observed in these patterns are described in terms of a Behaviour Cycle. The characteristics of the four distinct stages of this Cycle have been determined by studying the behaviour of thirty animals in response both to the coital activity of the male cat and to artificial sexual stimulation. The conspicuous external signs of the Cycle, together with the highly stereotyped pattern of Mating Behaviour which constitutes a sharp end-point for quantitative study, greatly facilitate the further investigation of sexual behaviour in this form. Nothing resembling oestrous or pro-oestrous behaviour was seen either in immature animals or in spayed adult females. Only behaviourally oestrous animals can be mated, and mating was never observed after removal of the ovaries during four hundred mating tests conducted with thirty animals over a period of fourteen months. It is concluded that the state of Sexual Receptivity in the female cat is strictly dependant upon the presence of ovarian hormone. Correlations are made between the behavioural patterns and the condition of the genital tract as revealed by vaginal smears; a highly significant association exists between the degree of vaginal cornification and the behavioural state at every stage of the oestrous cycle. Oestrous behaviour and mating continue throughout the period of vaginal oestrus. Mating behaviour in association with an anoestrous vaginal epithelium is a very rare occurrence in this form. The full organisation and development of the sexual reflexes in the female feline which result in the adoption of the full oestrous posture when stimulated artificially by vaginal probing is not necessarily associated with a state of sexual receptivity. It follows that the only certain criterion of Receptivity is a positive mating test conducted with an active male. Reasons have been given for putting forward the view that a central mechanism exists, underlying the development of the state of Receptivity, which requires a higher level of ovarian hormone for its activation than that required for the organisation of the segmental, postural reflexes. Attention has been drawn to the territory characteristics of the male as well as to spontaneously occurring distortions of sexual activity. Many of the aberrant patterns of sexual behaviour, which have been described in the literature as developing in brain-damaged animals, have been found to occur in unoperated animals simply as a result of laboratory conditioning and training.

Adaptation and ecotypic components

1956 ◽  
Vol 145 (920) ◽  
pp. 333-337 ◽  
Keyword(s):  
Ecotypic Variation ◽  
Habitat Gradient ◽  
Evolution Of Ideas

At the present time botanical ecotypic investigations are still concerned mainly with amplifying the records of ecotypically differentiated populations and defining their patterns, and only incidentally with the processes of ecotypic fractionation. That ‘strictly specialized ecotypes are frequently very uniform populations and practically homozygous in respect of many characters’ was the opinion of Sinskaia and other earlier workers in this field. However, the concept of the ecotype unit has been undergoing modification, and to get an impression of the evolution of ideas it is only necessary to examine the changes in the language by means of which the results of ecotypic studies have been recorded. The appearance of the terms deme* and ecocline is but a reflexion of the difficulty of describing the intricate patterns of variation in terms of discrete ecotypes. An ecotype is by definition the product arising as a result of the genotypical response of an ecospecies to a particular habitat. To establish an ecotypic relationship it is virtually essential to demonstrate that variational changes follow some recognizable habitat gradient. Thus established ecotypic variation will almost inevitably be recorded as ecoclinal.

scholarly journals The gut microbiome stability of a butterflyfish is disrupted on severely degraded Caribbean coral reefs

2020 ◽  
Author(s):  
Friederike Clever ◽  
Jade M. Sourisse ◽  
Richard F. Preziosi ◽  
Jonathan A. Eisen ◽  
E. Catalina Rodriguez Guerra ◽  
...  
Keyword(s):  
Coral Reefs ◽  
Gut Microbiome ◽  
Habitat Degradation ◽  
Coral Cover ◽  
Live Coral ◽  
Ecological Communities ◽  
Core Microbiome ◽  
Habitat Gradient ◽  
Fermentative Bacteria ◽  
Fish Gut

AbstractEnvironmental degradation has the potential to alter key mutualisms that underline the structure and function of ecological communities. While it is well recognized that the global loss of coral reefs alters fish communities, the effects of habitat degradation on microbial communities associated with fishes remain largely unknown despite their fundamental roles in host nutrition and immunity. Using a gradient of reef degradation, we show that the gut microbiome of a facultative, coral-feeding butterflyfish (Chaetodon capistratus) is significantly more variable among individuals at degraded reefs with very low live coral cover (~0%) than reefs with higher coral cover (~30%), mirroring a known pattern of microbial imbalance observed in immunodeficient humans and other stressed or diseased animals. We demonstrate that fish gut microbiomes on severely degraded reefs have a lower abundance of Endozoicomonas and a higher diversity of anaerobic fermentative bacteria, which suggests a broader and less coral dominated diet. The observed shifts in fish gut bacterial communities across the habitat gradient extend to a small set of potentially beneficial host associated bacteria (i.e., the core microbiome) suggesting essential fish-microbiome interactions are vulnerable to severe coral degradation.

Sign in / Sign up

Export Citation Format

Share Document