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2. Fish assemblage structure, habitat and microhabitat preference of five fish species in a small stream
- Creator:
- Vlach, Pavel, Dušek, Jan, Švátora, Miroslav, and Moravec, Pavel
- Type:
- article and TEXT
- Subject:
- microhabitat, brown trout, dace, chub, bullhead, and stone loach
- Language:
- English
- Description:
- Fish assemblage in the Úpoř brook was observed. The stream was inhabited by 13 fish species and Lampetra planeri. The abundance reached the mean value of 12175 spec.ha-1 and the mean biomass 395 kg.ha-1. Salmo trutta dominated, Cottus gobio was also very abundant and inhabited preferably riffles as well as Barbatula barbatula. Leuciscus cephalus and L. leuciscus were resident in pools. Other species occurred occasionally. Preferences in habitat and microhabitat use were evaluated using RDA and FE test. Two first axes of RDA explain 27.8% of total variability of all species, and 95.3% of relationship between the species and the environmental variables. These factors significantly correlated with the axes: distance from the mouth, maximum depth, presence of mud, presence of stones as shelters, presence of rocky shelters, and presence of the deposits. The character of substrates was the most important factor influencing the distribution of S. trutta, L. cephalus, L. leuciscus and B. barbatula, whereas C. gobio were greatly influenced by character of shelters. Also the distance from the mouth play a role in distribution of two last species. Seasonal changes in habitat preference of C. gobio were recorded.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
3. Gill parasites of Cephalopholis argus (Teleostei: Serranidae) from Moorea (French Polynesia): site selection and coexistence
- Creator:
- Lo, Cédrik M. and Morand, Serge
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- ectoparasites, Cephalopholis argus, French Polynesia, coral reef fish, microhabitat, spatial distribution, and parasite interactions
- Language:
- English
- Description:
- The distribution and coexistence of gill ectoparasites of 121 specimens of Cephalopholis argus Bloch et Schneider, caught between October 1994 and October 1995, were investigated. Adults of the monogenean Benedenia sp. and copepod Hatschekia sp., the larval caligid copepod Caligus sp. (copepodite and chalimus stages), and praniza larvae of the isopod Gnathia sp. were found. All species were aggregated within the host population. Infracommunities were poor, with only 40.5% of fish infected by two parasite species. Only two individual fish harboured all the parasite species observed at the component community level. Prevalences were less than 50% and mean intensities were low (less than 6 parasites/host). No dominant parasite species were observed in the host population. The spatial distribution of each parasite species was studied on different partitions of the gill arches. Adult parasite stages that are mobile showed much overlap in their distribution, whereas temporarily attached larvae of Caligidae were more site specific. Copepodite and chalimus larvae showed niche restriction that is probably due to gregarious behaviour. Positive associations between caligid larvae reflected intraspecific interaction for site and/or resources. Each of the Caligus sp. larval stages prefers specific sites, as do the adults, which occur exclusively in the buccal cavity of the host. Infracommunities were too poor and too few to induce processes of interspecific competition.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Habitat selection during spawning season of the spined loach, Cobitis sp. 'yamato' complex, in the Kyushu Islan, Japan
- Creator:
- Kim, Eun-Jin, Nakajima, Jun, and Onikura, Norio
- Type:
- article and TEXT
- Subject:
- microhabitat, reproductive season, flooded bank, temporary water, and Cypriniformes
- Language:
- English
- Description:
- Habitat selection of the spined loach yamato complex (Cobitidae) was investigated at the River Saigo, Fukuoka Prefecture, Kyushu Island, Japan, during both the non-spawning (from January to March) and spawning (from April to June) seasons. The study site had one pool, two riffles, and one flood region during the spawning season and is 140 m long, located 4 km stream from the river mouth. The number of yamato complex individuals was checked, and 10 physical environmental parameters were measured to assess the microhabitat in 45 quadrates. The number of individuals was counted each month, and environmental measurements were conducted four times from January to June 2010. Akaike’s Information Criterion (AICc) and Generalized Linear Model (GLM) were utilized for analysis to verify the effect of the important environmental variables on the habitat of the yamato complex. A total of 184 individuals were captured during the non-spawning and spawning seasons. The populations of yamato complex correlated positively with the water depth during the non-spawning season and with short emergent hydrophytes during the spawning season. Individuals of the yamato complex were observed in the riffle part of the river with depth during the non-spawning season and in the temporary water area with vegetation during the spawning season.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
5. Home range and habitat selection by Podarcis hispanica (Squamata, Lacertidae) in Western Spain
- Creator:
- Diego-Rasilla, Francisco Javier and Pérez-Mellado, Valentín
- Type:
- article and TEXT
- Subject:
- lizards, microhabitat, and electivity
- Language:
- English
- Description:
- A population of the lacertid lizard Podarcis hispanica was studied in the Sistema Central Mountains in Salamanca Province, Spain. Lizards confined their activities to stable home ranges, but size range varied enormously between individuals. Home ranges generally contained 1) a high proportion of rocks > 100 cm in height and 2) a significantly higher abundance of crevices than expected. The overall abundance of lizards increased with decreasing amounts of shrubs and herbaceous plants cover and densities were highest in bare and rocky areas. Adult females selected particular habitat types according to the season, whereas habitat selection of males and juveniles did not differ between spring and summer. Non-resident adult lizards and juveniles occupied habitats of marginal quality in relation to crevice abundance.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
6. Incidence of infection of carabid beetles (Coleoptera: Carabidae) by laboulbenialean fungi in different habitats
- Creator:
- Sugiura, Shinji, Yamazaki, Kazuo, and Masuya, Hayato
- Type:
- article, model:article, and TEXT
- Subject:
- Caleoptera, Carabidae, ectoparasitic fungi, Ascomycetes, laboulbenia, microhabitat, and overwintering sites
- Language:
- English
- Description:
- The prevalence of obligate parasitic fungi may depend partly on the environmental conditions prevailing in the habitats of their hosts. Ectoparasitic fungi of the order Laboulbeniales (Ascomycetes) infect arthropods and form thalli on the host's body surface. Although several studies report the incidence of infection of certain host species by these fungi, quantitative data on laboulbenialean fungus-host arthropod interactions at the host assemblage level are rarely reported. To clarify the effects of host habitats on infection by ectoparasitic fungi, the incidence of infection by fungi of the genus Laboulbenia (Laboulbeniales) of overwintering carabid beetles (Coleoptera: Carabidae) in three habitats, a riverside (reeds and vines), a secondary forest and farmland (rice and vegetable fields), were compared in central Japan. Of the 531 adults of 53 carabid species (nine subfamilies) collected in the three habitats, a Laboulbenia infection of one, five and one species of the carabid subfamilies Pterostichinae, Harpalinae and Callistinae, respectively, was detected. Three species of fungus were identified: L. coneglanensis, L. pseudomasei and L. fasciculate. The incidence of infection by Laboulbenia was higher in the riverside habitat (8.97% of individuals; 14/156) than in the forest (0.93%; 2/214) and farmland (0%; 0/161) habitats. Furthermore, the incidence of infection by Laboulbenia in the riverside habitat ranged from 0 to 33.3% and differed significantly in the ten microhabitats (riverbank, edge of track, tall reeds, kudzu vines, slope of a hollow, rotten wood, vine reeds, under stones, the shoulder of a terrace and marshy ground) where the carabid beetles overwintered. These results suggest that host habitats and microhabitats are closely associated with successful infection by laboulbenialean fungi.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Microhabitat preferences of Maculinea teleius (Lepidoptera: Lycaenidae) in a mosaic landscape
- Creator:
- Batáry, Péter, Örvössy, Noémi, Körösi, Ádám, Nagy, Marianna Vályi, and Peregovits, László
- Type:
- article, model:article, and TEXT
- Subject:
- Lycaenidae, Maculinea teleius, microhabitat, habitat use, foodplant, host ant, grazing, and wet meadow
- Language:
- English
- Description:
- The Scarce Large Blue (Maculinea teleius) is an endangered butterfly throughout Europe due to its special life-cycle and habitat loss. Our aims were to describe the microhabitats available to this butterfly, to test what factors influence the presence and density of M. teleius adults and to investigate the relationship between host ant species and M. teleius. The vicinities of eight fens were sampled, where there are four types of microhabitats available for this butterfly: Narrowleaf Cattail (Typha angustifolia), Purple Loosestrife (Lythrum salicaria), Marsh Woundwort (Stachys palustris) and Purple Moorgrass (Molinia coerulea) dominated vegetation. In five transects (50 × 5 m) around each fen (running from the edge of the fen into the meadows) the number of imagos was counted twice a day during the flight period. Along the transects, the following parameters were measured or assessed: number of flowerheads of foodplant (Sanguisorba officinalis), microhabitat type, grazing intensity, soil humidity, vegetation height and host ant presence. The four microhabitat types differed significantly in soil humidity, vegetation height, foodplant density and distance from a fen. Generally the Typha microhabitat, situated closest to fens, had the highest soil humidity and vegetation height, followed by the Lythrum, Stachys and finally the Molinia microhabitat along a gradient decreasing soil humidity and vegetation height. The foodplant was most abundant in the Lythrum and Stachys microhabitats. Using linear mixed models and forward stepwise manual selection we found that microhabitat type was the most important factor determining the presence of M. teleius. The local grazing intensity had no direct effect but flowerheads of the foodplant had a positive effect on the abundance of butterflies. The number of butterflies was significantly higher in quadrats where the host ant (Myrmica scabrinodis) was present compared to those where they were absent. Our results suggest that grazing should be continued in order to maintain the current distribution of microhabitats and survival of the butterflies.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
8. Microhabitat selection of Discocotyle sagittata (Monogenea: Polyopisthocotylea) in farmed rainbow trout
- Creator:
- Rubio-Godoy, Miguel
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Monogenea, Discocotyle sagittata, microhabitat, trout, and Oncorhynchus mykiss
- Language:
- English
- Description:
- Microhabitat preference of the monogenean Discocotyle sagittata (Leuckart, 1842) was determined in late spring and late autumn in rainbow trout, Oncorhynchus mykiss (Walbaum), reared in the Isle of Man, UK. Discocotyle sagittata exhibits a preference for attachment to anterior gill arches: 29% of all worms occurred on gill arch I, 28% on II, 25% on III and 18% on IV. This distribution pattern on the introduced salmonid species is the same as reported for its native European host, the brown trout Salmo trutta (L.). Previous experimental work suggested that invasion is a passive process followed by post-invasion migration to anterior gill arches; the present work provides evidence of equivalent site selection taking place in fishes maintained under conditions promoting continuous reinfection in aquaculture. Migration may be density-dependent, since a significant inverse association was found between the intensity of mature parasites and their proportion on anteriormost gill arch I.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9. Microhabitats of Pseudodactylogyrus anguillae and P. bini (Monogenea: Dactylogyridae) on the gills of large-size European eel Anguilla anguilla from Lake Gaj, Poland
- Creator:
- Dzika, Ewa
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Pseudodactylogyrus, microhabitat, distribution, and Monogenea
- Language:
- English
- Description:
- A study on the spatial distribution of two congeneric monogenean species Pseudodactylogyrus anguillae Yin ct Sproston, 1948 and P. bini Kikuchi, 1929 on the gills of large size European eel Anguilla anguilla (L.) were conducted. Results were analysed with regard to: single-species infection, mixed infection and general occurrence of the parasites in the ccl population. Statistical analysis revealed that the distribution of these species on the gill apparatus is fairly similar and the zones in which they occur more numerously coincide to a great extent. However, a number of differences were found. Both the possibility of simultaneous occurrence on Ihe host and similar distribution of the above species on the eel’s gills indicate the reciprocal tolerance of these parasites.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10. Sexual segregation of Echinorhynchus borealis von Linstow, 1901 (Acanthocephala) in the gut of burbot (Lota lota Linnaeus)
- Creator:
- Tuomainen, Arto, Valtonen, E. Tellervo, and Benesh, Daniel P
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- poměr pohlaví, sex ratio, thorny-headed worms, body size, Echinorhynchidae, Echinorhynchus cinctulus, microhabitat, niche, spatial distribution, 2, and 59
- Language:
- English
- Description:
- Helminths often occupy defined niches in the gut of their definitive hosts. In the dioecious acanthocephalans, adult males and females usually have similar gut distributions, but sexual site segregation has been reported in at least some species. We studied the intestinal distribution of the acanthocephalan Echinorhynchus borealis von Linstow, 1901 (syn. of E. cinctulus Porta, 1905) in its definitive host, burbot (Lota lota Linnaeus). Over 80% of female worms were found in the pyloric caeca, whereas the majority of males were in the anterior two-thirds of the intestine. This difference was relatively consistent between individual fish hosts. Worms from different parts of the gut did not differ in length, so site segregation was not obviously related to worm growth or age. We found proportionally more males in the caeca when a larger fraction of the females were found there, suggesting mating opportunities influence gut distribution. However, this result relied on a single parasite infrapopulation and is thus tentative. We discuss how mating strategies and/or sexual differences in life history might explain why males and females occupy different parts of the burbot gut., Arto Tuomainen, E. Tellervo Valtonen, Daniel P. Benesh., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public