On the proposed conservation of the specific name of Xerophila geyeri Soos, 1926 (Mollusca, Gastropoda)

Volume: 52Start Page: 331End Page: 33

Cepaea nemoralis (L.) in Goteborg, S.W. Sweden: variation in a recent urban invader

Although present since the mid 19th century, the introduced snail species Cepaea nemoralis has spread extensively in Göteborg, mainly in the last two decades. Early samples show the predominance of yellow-shelled morphs, but in modern populations pink shells predominate. There is great variation in morph frequencies among modern populations with high values of F ST , and with no relationships to habitat. The patterns shown resemble those seen in Sheffield (UK), a city also colonised over a similar time period, but differ from those seen in regions where the species has been established for much longer. The combination of early and recent records suggests not only that founder effects play a large part in determining morph frequencies, but that present populations derive from multiple colonisations from different sources

Density-dependent reproductive output in relation to a drastically varying food supply: getting the density measure right

When a limiting resource (e.g. food) varies drastically between years, and population density is measured in the conventional way as individuals per area, demographic processes such as productivity and survival may erroneously be considered density-independent. We tested the hypothesis that if the variation in a limiting resource is not taken into account in the density measure, this may lead to erroneous conclusions about the density-dependence of demographic variables. We studied the food-related variation in productivity of bramblings Fringilla montifringilla, an insectivorous passerine bird, using 19 years of standardised insect censusing, bird censusing and mist-netting of birds in subalpine birch forest in Swedish Lapland. The yearly variation in our measure of brambling per capita productivity (numbers of juveniles per adult trapped) was explained to 30-40% by the larvae abundance of the moth Epirrita autumnata. Taking larvae density into account, no other environmental variable (inferred predation pressure, breeding phenology, and summer temperature) was significantly related to variation in reproductive output. There was no effect of brambling population density on per capita productivity, that is, when density was measured the conventional way, productivity seemed density-independent. However, per capita productivity was significantly and negatively correlated to the food-related population density (population density divided by larval density), supporting the hypothesis that not including a limiting resource into the density measure may indeed lead to erroneous conclusions about the density-dependence of demographic variables

How to trap a slug: Commercial versus homemade slug traps

The Iberian Slug, Arion lusitanicus Mabille (Stylomatophora: Arionidae), has developed into a destructive pest in Swedish gardens and orchards over the past 10-20 years. Many attempts to eradicate this pest have been made using a variety of different methods. The aim of this study was to investigate the effectiveness of two different types of homemade traps made from simple, inexpensive materials (plastic PET bottle or an ice-cream box) compared to one type of commercially sold trap (Slugtrap((R)) IT-PAC A B, Sweden) used with bait and beer as attractants. Experiments were carried out on a private property outside Lund, Sweden, over a period of 7 days. The results showed that a homemade trap, i.e. a box trap, can be as efficient as a commercial trap, particularly due to their similar design. In contrast, the homemade bottle trap was not very successful. Additionally, it was discovered that the bait used in the commercial traps did not increase the number of slugs trapped. It was concluded that the beer was the main slug attractant. Ultimately this study suggests a low-cost alternative for small scale to the rather expensive commercially sold traps

Comments on the proposed conservation of Hydrobia Hartmann, 1821 (Mollusca, Gastropoda) and Cyclostoma acutum Draparnaud, 1805 (currently Hydrobia acuta) by the replacement of the lectotype of H. acuta with a neotype; proposed designation of Turbo ventrosus Montagu, 1803 as the type species of Ventrosia Radoman, 1977; and proposed emendation of spelling of Hydrobiina Mulsant, 1844 (Insecta, Coleoptera) to Hydrobiusina, So removing the homonymy with Hydrobiidae Troschel, 1857 (Mollusca)

Volume: 56Start Page: 56End Page: 6

The Significance of Alien and Invasive Slug Species for Plant Communities in Agrocenoses

This paper lists alien invasive species of slugs occurring on crops grown in the ground and under covers, as well as in adjacent habitats. It gives a description of their origin, distribution within Poland, frequency of occurrence in different habitats, and an evaluation of the danger to cultivated plants posed by particular slug species. Based on reports in the literature and the results of original research, basic data is presented concerning the biology and harmfulness of these slugs on crops. The potential risk of the spreading of invasive slug species is evaluated, as well as their adverse impact on crop plants. It has been concluded that a major risk to the biodiversity of agrocenoses and to cultivated plants is currently posed by the slugs Arion lusitanicus, A. rufus and A. distinctus. These slugs are spreading rapidly within Poland, often occur in large numbers, and do significant damage to various species of plant