Effects of isolation, habitat size and several microhabitat variables on presence/absence of the monophagous Bolitophagus reticulatus (L.) (Coleoptera. Tenebrionidae) were investigated in 58 forest fragments in an agricultural landscape (15 km2) in south‐eastern Norway, All potential habitats of the beetle, dead Fomes fomentarius (L,) Kiekx basidiocarps (n = 587), were collected from trees (n = l85) within the study area. The basidiocarps were dissected and the number of B, reticulatus specimens (larvae, pupae and adults) counted. The material was analysed at four distinguishable spatial scales; basidiocarp‐. tree‐, tree‐group‐ and forest island level. Different patterns of beetle presence emerged at the different scales, increasing habitat size and decreasing degree of isolation increased the probability of B, reticulatus presence at three (basidiocarp‐, tree‐ and forest island level) and one (tree level) scales, respectively, whilst no such trends were found at the fourth level (tree‐group level). Increasing insolation and thereby higher ambient temperatures, indicated by several microhabitat variables, improved the probability of beetle presence amongst the trees. The number of beetle specimens correlated positively with an increase in the habitat size at the tree level.

SUMMARYHead lice prevalence varies greatly between and within countries, and more knowledge is needed to approach causes of this variation. In the present study, we investigated head lice prevalence among elementary school students and their households in relation to individual and household characteristics as well as spatial variables. The investigation included households from 5 geographically separated municipalities. Present infestations among household members as well as previous infestations in the household were reported in a questionnaire. In elementary school students prevalence was low (1·63%), but more than one-third of the households (36·43%) had previously experienced pediculosis. Prevalence was higher in elementary school students than in other household members, and highest in third-grade children. Prevalence was also influenced by the school attended, which suggested that interactions between children in the same school are important for head lice transmission. Previous occurrence of head lice in homes also increased the risk of present infestation. Prevalence of previous infestations was higher in households with more children and in more densely populated municipalities, indicating that the density of hosts or groups of hosts influences transmission rates. These results demonstrate that information of hosts’ spatial distribution as well as household and individual characteristics is needed to better understand head lice population dynamics.

The effect of habitat fragmentation on genetic differentiation among local populations of the fungivorous beetle Bolitophagus reticulatus (Coleoptera: Tenebrionidae) was studied in two contrasting landscapes: one heavily fragmented with forest fragments of variable size surrounded by inhabitable agricultural fields, the other an old forest providing a continuous habitat. The genetic structure of the beetle within each of the two contrasting areas was investigated by means of protein electrophoresis, screening four polymorphic loci in 20 populations from each area. In both areas there were significant genetic differences among local populations, but on average differentiation in the fragmented area was three times greater than in the continuous one, strongly indicating a genetic isolation effect of habitat fragmentation. These genetic results are in accordance with previous studies on dispersal in this species.

Negative effects of habitat fragmentation (increased isolation and reduced habitat size) affected presence of several beetle species inhabiting Fomes fomentarius (L.) Kickx basidiocarps in a fragmented forest landscape. At the scale of individual trees (tree level), incidence of Cis jacquemarti Mell./C. nitidus (F.) (not distinguished between individuals of these two species, abbreviated C. jacquemarti /nitidus), C. bidentatus (Ol.), C. lineatocribratus Mell., Ennearthron cornutum (Gyll.) (all Coleoptera, Cisidae) and Dorcatoma dresdensis Herbst (Coleoptera, Anobiidae) was reduced with increased habitat isolation and reduced habitat size. Additionally, increased habitat size at a larger scale (forest island level) also gave higher incidence of all species. Some of the microhabitat variables measured influenced upon the presence of the study species. Fallen trees had a higher probability of C. jacquemarti / nitidus presence than standing trees, whilst the opposite was the case for C. bidentatus. There was also increased incidence of C. bidentatus on trees in denser forests and of E. cornutum in grey alder Alnus incana compared with birch trees (Betula spp.). Increased volume of basidiocarps on a tree resulted in a higher number of individuals of C. jacquemarti / nitidus and C. lineatocribratus.

Introduction Head lice infestations cause distress in many families. A well-founded strategy to reduce head lice prevalence must shorten the infectious period of individual hosts. To develop such a strategy, information about the actions taken (inspection, treatment and informing others about own infestations), level of knowledge and costs is needed. The present study is the first to consider all these elements combined. Materials and Methods A questionnaire was answered by 6203 households from five geographically separated municipalities in Norway. Results 94% of the households treated members with pediculicides when head lice were discovered. Nearly half of the households checked biannually or not at all. Previous occurrence of head lice and multiple children in a household improved both checking frequency and method. More than 90% of the households informed close contacts about their own pediculosis. Direct costs of pediculosis were low (less than €6.25 yearly) for 70% of the households, but the ability to pay for pediculicides decreased with the number of head lice infestations experienced. One in three households kept children from school because of pediculosis. Other widespread misconceptions, such as that excessive cleaning is necessary to fight head lice, may also add unnecessary burden to households. School affiliation had a significant effect on checking frequency and method, knowledge and willingness to inform others about own pediculosis. Conclusions Increased checking frequencies appear to be the most important element to reduce head lice prevalence in Norway and should be a primary focus of future strategies. National campaigns directed through schools to individual households, might be an important tool to achieve this goal. In addition to improving actions taken, such campaigns should also provide accurate information to reduce costs and enhance the level of knowledge about head lice in households.