Seasonal activity of caddisflies (Insecta: Trichoptera) in the Börzsöny Mountains, North Hungary

Trichoptera were collected by light trapping in the Börzsöny Mountains in 1996,1998 and 1999 at Bernecebaráti and Királyrét. Caddisflies were listed into the following flight period types: short, medium or long flight activity, and autumn or summer species. The weekly flight activity patterns of some caddisfly species and their comparison are discussed

Comparison of species richness of light trap-collected caddisfly assemblages (Insecta: Trichoptera) using rarefaction

ConselVation value of light trap-collected caddisfly assemblages(Insecta: Trichoptera) was evaluated on the basis of their species richness. The assemblage coming from an artificial stream showed a higher conservation value based on species richness than the natural ones. In contrast, using rarefaction, the conservation value of the assemblage in the artificial stream was lower in comparison with assemblages in natural habitats. Further examples are given to demonstrate the importance of rarefaction in comparing species richness of assemblages

Notes on the larval habitat preference and microdistribution of Potamophylax rotundipennis (Insecta: Trichoptera) in a stream reach of the Börzsöny Mountains (Northern Hungary)

Larval habitat preference of Potamophylax rotundipennis (Insecta: Trichoptera) was examined under natural conditions. The result of this study indicated a high preference for stone to sand and detritus, and preference for the low depth of water. This preference resulted that P. rotundipennis larvae showed a homogenous distribution along the stream-reach, but not across it

Effect of riverbed morphology, stream order and season on the structural and functional attributes of caddisfly assemblages (Insecta: Trichoptera)

We tested the individual and joint effects of stream order, riverbed morphology (i.e. pool-riffle sequence), and season on the structural (i.e. species composition, density and richness) and functional (i.e. percent ratio of shredders, collectors, scrapers, and predators) properties of caddisfly assemblages in a closely natural headwater system (Börzsöny Mts., North Hungary). Each factor, both individually and in interaction had a significant effect on caddisfly assemblages as shown by MANOVA analyses. To clarify the effects of stream order, riverbed morphology and season on caddisflies, assemblage properties were also separately studied by ANOVAs. Percent ratio of shredders and collectors were strongly affected by all factors, whereas other attributes were not always sensitive to stream order, season and riverbed morphology. In contrast, species compositions of the reaches differing in stream order and riverbed morphology were significantly different. Our findings on the contrasting differences in shredder composition between riffles and pools may suggest that not only riparian vegetation, but also instream habitat features could shape the accumulation and retention of particulate organic matter (in streams with pool-riffle heterogeneity)

Estimating sample representativeness in a survey of stream caddisfly fauna

Obtaining an adequate and representative sample is a continuing challenge of community ecology. The present study focuses on what sample area represents adequately the structural composition of the caddisfly fauna of a riffle, at a given sampling occasion. Sixty-two Surber samples were collected from a riffle in a second-order reach of the Bernecei Stream (Börzsöny Mountains, Hungary). This data set was used to estimate sample representativeness at different sample sizes (from 1 to 31 Surber samples, 0.09 m2 - 2.79 m2) generated a re-sampling procedure. Sample representativeness was measured with mean Jaccard Coefficient and Bray-Curtis Index between samples for species presence-absence data and abundance data, respectively. We found that a sample size of 2.25 m2 represented well (mean similarity 0.998) the species composition of the caddisfly fauna if rare species were excluded from the analysis. In contrast, sample representativeness of species composition proved to be relatively low (0.719) if rare species were included in the analysis. Curves of sample representativeness based on both raw-, or transformed abundance data were less sensitive to the presence of rare species and showed lower representativeness than sample representativeness based on presence/absence data

A new measure of conservation value combining rarity and ecological diversity: a case study with light trap collected caddisflies (Insecta: Trichoptera)

The objective of the present study was to analyse the conservation importance of streams, rivers and lakes for maintaining caddistly assemblages of Hungarian localities. Light traps ensured comparable catches of caddisflies from different aquatic habitats. A total of 245,363 individuals belonging to 152 species collected from 23 localities over the flight period were included in the analysis. Conservation value of caddistly assemblages was evaluated on the basis of a newly developed Rarity and Ecological Diversity (RED)-index expressing ecological diversity and the average rarity of caddistlies in Hungarian localities. The results showed that streams were the most suitable habitats for maintaining rare caddisfly species in diverse assemblages, while rivers had the lowest conservation importance

Tegzeslárvák (Insecta: Trichoptera) koegzisztenciális mintázatai börzsönyi kisvízfolyások szakasz térskálaszintjén | Coexistence patterns of caddisfly larvae (Insecta: Trichoptera) in the streams of the Börzsöny Mountains (North Hungary)

Most of the community ecological studies examining effect of habitat template on biota. In the present study, I focused on interactions among species or in other words on “assemblage rules” that shape community organisation of caddisfly larvae assemblages in submountane streams of Hungary. This study suggests that there are not, or only weak interactions among caddisfly species based on the co-occurrence analysis of samples representing different stream reaches of the Börzsöny Mountains (North Hungary)

A method for the quantitative evaluation of the endangerment status of Trichoptera assemblages in Hungary

An endangered species categorisation of the Hungarian Trichoptera has been proposed by NÓOMDI and UHERKOVICH(1999). However, their list did not allow a quantitative evaluation of the degree of endangerment. Here an attempt is made to calculate an index of endangerment among the different groups of the endangered species categorisation of NÓOMDI and UHERKQVICH (1999)