@article{ApioPlathWronski2006, author = {Apio, Ann and Plath, Martin and Wronski, Torsten}, title = {Patterns of gastrointestinal parasitic infections in the bushbuck Tragelaphus scriptus from the Queen Elizabeth National Park, Uganda}, series = {Journal of helminthology}, volume = {80}, journal = {Journal of helminthology}, number = {3}, publisher = {Univ. Press}, address = {Cambridge}, issn = {0022-149X}, doi = {10.1076/JOH2006343}, pages = {213 -- 218}, year = {2006}, abstract = {Seasonal, host sex and age-related variations in helminth egg and coccidian oocyst counts were investigated in a naturally infected wild bushbuck (Tragelaphus scriptus) population in Queen Elizabeth National Park, western Uganda from April 2000 to February 2002. The prevalence and mean intensity quantified as the number of eggs and oocysts per gram of faeces were taken as a measure of parasite burdens. Host sex and age-related differences in prevalence values were not found but the overall prevalence of Eimeria sp. was significantly higher during the rainy season, and peak counts were recorded either during or soon after a peak rainfall. A similar trend was observed for Moniezia spp., although the results were marginally not significant. There were also no significant differences in mean intensity values, relative to host sex, age or season.}, language = {en} } @article{RieschSchluppTobleretal.2006, author = {Riesch, R{\"u}diger and Schlupp, Ingo and Tobler, Michael and Plath, Martin}, title = {Reduction of the association preference for conspecifics in cave-dwelling Atlantic mollies, Poecilia mexicana}, series = {Behavioral ecology and sociobiology}, volume = {60}, journal = {Behavioral ecology and sociobiology}, publisher = {Springer}, address = {New York}, issn = {0340-5443}, doi = {10.1007/s00265-006-0223-z}, pages = {794 -- 802}, year = {2006}, abstract = {Cave animals are widely recognised as model organisms to study regressive evolutionary processes like the reduction of eyes. In this paper, we report on the regressive evolution of species discrimination in the cave molly, Poecilia mexicana, which, unlike other cave fishes, still has functional eyes. This allowed us to examine the response to both visual and non-visual cues involved in species discrimination. When surface-dwelling females were given a chance to associate with either a conspecific or a swordtail (Xiphophorus hellerii) female, they strongly preferred the conspecific female both when multiple cues and when solely visual cues were available to the female. No association preference was observed when only non-visual cues were provided. In contrast, cave-dwelling females showed no preference under all testing conditions, suggesting that species recognition mechanisms have been reduced. We discuss the role of species discrimination in relation to habitat differences.}, language = {en} } @article{WronskiApioPlath2006, author = {Wronski, Torsten and Apio, Ann and Plath, Martin}, title = {Activity patterns of bushbuck (Tragelaphus scriptus) in Queen Elizabeth National Park}, series = {Behavioural processes}, volume = {73}, journal = {Behavioural processes}, number = {3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0376-6357}, doi = {10.1016/j.beproc.2006.08.003}, pages = {333 -- 341}, year = {2006}, abstract = {Activity patterns and time budgets of bushbuck (Tragelaphus scriptus) were studied in a free-ranging population in Queen Elizabeth National Park, Uganda from August 2000 to January 2002. We investigated differences in activity patterns in relation to daytime, season, sun radiation, moonlight, age and sex. Bushbuck were found to show peak activities around sunrise and at dawn. No difference in the mean activity rates was found between the dry and wet season. Daytime activity was not predicted by differences in sun radiation, nor was nighttime activity predicted by the presence or absence of moonlight. We found the activity of adult territorial males to be strongly positively correlated with that of females, whereas the activity of young-adult non-territorial males was not significantly correlated with the activity of females. This suggests that young-adult males shift their peak activity to phases when adult territorial males are less active.}, language = {en} } @article{ToblerSchluppHeubeletal.2006, author = {Tobler, Michael and Schlupp, Ingo and Heubel, Katja U. and Riesch, Rudiger and Garcia de Leon, Francisco J. and Giere, Olav and Plath, Martin}, title = {Life on the edge: hydrogen sulfide and the fish communities of a Mexican cave and surrounding waters}, series = {Extremophiles : life under extreme conditions}, volume = {10}, journal = {Extremophiles : life under extreme conditions}, publisher = {Springer}, address = {Tokyo}, issn = {1431-0651}, doi = {10.1007/s00792-006-0531-2}, pages = {577 -- 585}, year = {2006}, abstract = {Most eucaryotic organisms classified as living in an extreme habitat are invertebrates. Here we report of a fish living in a Mexican cave (Cueva del Azufre) that is rich in highly toxic H2S. We compared the water chemistry and fish communities of the cave and several nearby surface streams. Our study revealed high concentrations of H2S in the cave and its outflow (El Azufre). The concentrations of H2S reach more than 300 mu M inside the cave, which are acutely toxic for most fishes. In both sulfidic habitats, the diversity of fishes was heavily reduced, and Poecilia mexicana was the dominant species indicating that the presence of H2S has an all-or-none effect, permitting only few species to survive in sulfidic habitats. Compared to habitats without H2S, P. mexicana from the cave and the outflow have a significantly lower body condition. Although there are microhabitats with varying concentrations of H2S within the cave, we could not find a higher fish density in areas with lower concentrations of H2S. We discuss that P. mexicana is one of the few extremophile vertebrates. Our study supports the idea that extreme habitats lead to an impoverished species diversity.}, language = {en} } @article{ToblerPlathBurmeisteretal.2006, author = {Tobler, Michael and Plath, Martin and Burmeister, Heike and Schlupp, Ingo}, title = {Black spots and female association preferences in a sexual / asexual mating complex (Poecilia, Poecilildae, Teleostei)}, doi = {10.1007/s00265-005-0152-2}, year = {2006}, abstract = {We investigated whether female association preferences for males are influenced by black spot disease (BSD), a parasite induced change of the host phenotype. We compared three different species of fish: a gynogenetic hybrid species, Poecilia formosa (amazon molly) and two sexual species (Poecilia latipinna and Poecilia mexicana), which were involved in the natural hybridisation leading to the amazon molly. Contrary to their sexual relatives, asexual amazon mollies significantly avoided images of males infected with black spot disease. We propose that amazon molly females have direct fitness benefits from choosing healthy males. The adaptive significance of the preference for BSD-uninfected males in the asexual amazon molly is yet unclear but may involve avoidance of predation or parasite infection as well as increased sperm availability}, language = {en} } @article{ApioPlathWronski2006, author = {Apio, Ann and Plath, Martin and Wronski, Torsten}, title = {Localised defecation sites : a tactic to avoid re-infection by gastro-intestinal tract parasites in bushbuck, Tragelaphus scriptus?}, issn = {0289-0771}, doi = {10.1007/s10164-005-0166-2}, year = {2006}, abstract = {Bushbuck (Tragelaphus scriptus) often deposit faeces at specific localised defecation sites (LDS). We tested whether LDS have a function in the context of parasite avoidance. In a population of bushbuck in Queen Elizabeth National Park, Uganda, seven radio-collared individuals were observed. We recorded feeding behaviour inside and outside LDS. Furthermore, pasture contamination with gastro-intestinal tract parasites inside and outside LDS was examined. There were significant differences between the expected and the observed feeding rates inside LDS, but, contrary to our prediction, the bushbuck increased their feeding rate inside LDS. There was no significant difference in the parasite contamination of pastures inside and outside LDS. We discuss the hypothesis that LDS mainly serve a social function in bushbuck communities, whereas parasite avoidance seems to play a minor or no role}, language = {en} } @article{PlathRohdeSchroederetal.2006, author = {Plath, Martin and Rohde, Matthias and Schr{\"o}der, Thekla and Taebel-Hellwig, Angelika and Schlupp, Ingo}, title = {Female mating preferences in blind cave tetras Astyanax fasciatus (Characidae, Teleostei)}, issn = {0005-7959}, doi = {10.1163/156853906775133560}, year = {2006}, abstract = {The Mexican tetra Astyanax fasciatus has evolved a variety of more or less color- and eyeless cave populations. Here we examined the evolution of the female preference for large male body size within different populations of this species, either surface- or cave-dwelling. Given the choice between visual cues from a large and a small male, females from the surface form as well as females from an eyed cave form showed a strong preference for large males. When only non-visual cues were presented in darkness, the surface females did not prefer either males. Among the six cave populations studied, females of the eyed cave form and females of one of the five eyeless cave populations showed a preference for large males. Apparently, not all cave populations of Astyanax have evolved non-visual mating preferences. We discuss the role of selection by benefits of non-visual mate choice for the evolution of non-visual mating preferences}, language = {en} } @article{PoschadelMeyerLuchtPlath2006, author = {Poschadel, Jens R. and Meyer-Lucht, Yvonne and Plath, Martin}, title = {Response to chemical cues from conspecifics reflects male mating preference for large females and avoidance of large competitors in the European pond turtle, Emys orbicularis}, issn = {0005-7959}, doi = {10.1163/156853906776759510}, year = {2006}, abstract = {We examined chemical communication in male and female European pond turtles (Emys orbicularis). In simultaneous binary choice tests, a focal animal was given a choice between pheromones from a conspecific and a choice chamber containing untreated water. Females did not show a preference, both when male and when female stimuli were presented. On the contrary, males preferred the odor of a female over untreated water, suggesting that males actively search for females. The strength of preference was positively correlated with the body size difference between the female and the focal male, indicating that males prefer to mate with larger females. Female fecundity is positively correlated with female size in E. orbicularis, which may account for male choosiness. No overall preference for the stimulus animal was observed when males were presented cues from another male. However, the strength of preference was negatively correlated with the difference in body size. Males avoided large males, but oriented towards smaller stimulus males. This reflects that males form dominance hierarchies, where large males aggressively attack smaller ones. Far-range chemical communication probably enables males to minimize the risk of costly aggressive interactions. This is, to our knowledge, the first study on the role of chemical cues for inter-and intrasexual communication in the European pond turtle}, language = {en} } @article{WronskiApioPlath2006, author = {Wronski, Torsten and Apio, Ann and Plath, Martin}, title = {The communicatory significance of localised defecation sites in bushbuck (Tragelaphus scriptus)}, doi = {10.1007/s00265-006-0174-4}, year = {2006}, abstract = {Like several other mammals, bushbuck (Tragelaphus scriptus) deposit faeces in specific localised defecation sites (LDS). A previous study has ruled out a function of LDS in the context of parasite avoidance. In this study, we investigated the communicatory significance of LDS. In a free ranging population, we tested whether LDS serve to demarcate home ranges, and/or if LDS are used for communication in a non-territorial context. In both sexes, LDS increased significantly in number towards the periphery of individual home ranges. However, the distribution pattern of LDS, as revealed by a nearest-neighbour mapping technique (nearest distances between LDS), did not support the idea that LDS serve home range/territory-demarcation because LDS did not follow a pattern of minimal nearest-neighbour distances along the margins of home ranges. We found females to urinate more often in LDS than males. Notably, information transfer was most frequent between sending (urinating or defecating) females and receiving/responding males (urination or defecation at places where a female had previously signalled). Our results suggest that LDS mainly serve for inter- sexual communication in bushbuck}, language = {en} } @article{WronskiTiedemannApioetal.2006, author = {Wronski, Torsten and Tiedemann, Ralph and Apio, Ann and Plath, Martin}, title = {Cover, food, competitors and individual densities within bushbuck Tragelaphus scriptus female clan home ranges}, year = {2006}, abstract = {We examined factors predicting female densities within the common home ranges of related females ("clans") in bushbuck Tragelaphus scriptus Pallas, 1776. In this species, each female forms an individual home range, but the home ranges of matrilineal clan members strongly overlap. We found female densities to increase in areas with high canopy cover. Moreover, individual home range sizes tended to decrease with increasing cover. Food plant availability and intruder pressure by two heterospecific competitors did not significantly affect female densities. Apparently, canopy cover is the major limited resource in this species. A possible explanation is that both adult bushbuck and - even more markedly - fawns hide from predators in dense vegetation, in particular in thicket clumps and coalescences. The study shows an effect of habitat properties (eg sufficient canopy cover) on a within-population level in bushbuck, where female densities differ even among proximate clan areas}, language = {en} }