Demographics of the European hare (Lepus europaeus) in the Mediterranean climate zone of Australia

Demographic parameters of the European hare (Lepus europaeus) in southern Australia were investigated by dissecting hares shot by hunters during each month of the year. Gender, body weight, age, sucking, lactation, weight of the abdominal alimentary canal, weight of the left peri-renal fat body, pregnancy status, presence and counts of placental scars, litter size, and stage of gestation were recorded. From those data, growth rates, age at weaning, age and weight at puberty, date of conception, projected birth date, recruitment, survivorship, and the relationships between lactation and fat stores and alimentary capacity were determined.Fecundity of the southern Australian hares followed the seasonal pattern reported for northern hemisphere populations. However, output was lower per female and particularly per older female. Females began breeding at an earlier age such that recruitment into the southern Australian population was more dependent on females in their first year of life than on older females. Growth rates were comparable with European rates. Although high chill factors were apparently associated with higher leveret mortality, there was paradoxically higher overall mortality during the spring-early summer period of higher plant growth than in the late summer–winter period of lower plant growth and more extreme weather conditions. Fat was accumulated during pregnancy and would act as a buffer against the possibility of inadequate food availability during lactation, but hares increased the capacity of the alimentary canal during lactation and presumably with it their ability to assimilate energy to meet the demands of lactation.     

Status and distribution of European Nightjars Caprimulgus europaeus in the UK in 2004

Capsule The population of Nightjars in the UK increased by over 36% between 1992 and 2004.

Aims To determine the population size and distribution of Nightjars in the UK and examine associations with forestry and heathland habitat features.

Methods A volunteer survey was supported by professional cover in remote parts of Wales, and areas of Dorset and lowland Scotland. Two visits to allocated 1-km squares were made between late May and mid-July. Each surveyor recorded the locations of calling males onto maps and the occurrence of habitat categories within 50 m of each Nightjar registration.

Results Observers surveyed 3264 1-km squares in 2004 and, on average, 78% of the target habitat (90% in southern England). The total number of males counted was 4131 (range 3850–4414), adjusted to 4606 (95% CL ± 913) to account for unsurveyed habitat. The adjusted total represented a 36% increase in 12 years. Nightjars were recorded in 275 10-km squares in 2004, a 2.6% increase since 1992. However, there was evidence of population decline and range contractions in northwest Britain, including north Wales, northwest England and in Scotland. In 2004, 57% of Nightjars were associated with forest plantations (similar to 1992) and 59% with heathland (slightly higher than in 1992).

Conclusion National objectives for Nightjar conservation (UK Biodiversity Action Plan: UKBAP) were reached in respect of population size and stability, but the target for a 5% range increase by 2003 was not met. The continued increase in the national population is probably attributable to habitat protection, management and restoration of heathlands, and the continued availability of clear-fell/young plantations in conifer forests. Management and/or protection/restoration/re-creation of these key habitats remains critical for the long-term objectives of UKBAP. The issue of providing foraging habitats, perhaps via agri-environment schemes, is also raised.     

Phylogeography of the brown hare (Lepus europaeus) in Europe: a legacy of south‐eastern Mediterranean refugia?

Aim We analysed the population genetics of the brown hare (Lepus europaeus) in order to test the hypothesis that this species migrated into central Europe from a number of late glacial refugia, including some in Asia Minor. Location Thirty‐three localities in Greece, Bulgaria, Italy, Croatia, Serbia, Poland, Switzerland, Austria, France, Germany, the Netherlands, Spain, the United Kingdom, Turkey and Israel. Methods In total, 926 brown hares were analysed for mitochondrial DNA (mtDNA) variation by restriction fragment length polymorphism (RFLP) performed on polymerase chain reaction‐amplified products spanning cytochrome b (cyt b)/control region (CR), cytochrome oxidase I (COI) and 12S–16S rRNA. In addition, sequence analysis of the mtDNA CR‐I region was performed on 69 individuals, and the data were compared with 137 mtDNA CR‐I sequences retrieved from GenBank. Results The 112 haplotypes detected were partitioned into five phylogeographically well‐defined major haplogroups, namely the ‘south‐eastern European type haplogroup’ (SEEh), ‘Anatolian/Middle Eastern type haplogroup’ (AMh), ‘European type haplogroup, subgroup A’ (EUh‐A), ‘European type haplogroup, subgroup B’ (EUh‐B) and ‘Intermediate haplogroup’ (INTERh). Sequence data retrieved from GenBank were consistent with the haplogroups determined in this study. In Bulgaria and north‐eastern Greece numerous haplotypes of all five haplogroups were present, forming a large overlap zone. Main conclusions The mtDNA results allow us to infer post‐glacial colonization of large parts of Europe from a late glacial/early Holocene source population in the central or south‐central Balkans. The presence of Anatolian/Middle Eastern haplotypes in the large overlap zone in Bulgaria and north‐eastern Greece reveals gene flow from Anatolia to Europe across the late Pleistocene Bosporus land‐bridge. Although various restocking operations could be partly responsible for the presence of unexpected haplotypes in certain areas, we nevertheless trace a strong phylogeographic signal throughout all regions under study. Throughout Europe, mtDNA results indicate that brown hares are not separated into discernable phyletic groups.     

Variation in predation costs with Chiastocheta egg number on Trollius europaeus: how many seeds to pay for pollination?

1. In obligate plant/seed parasite–pollinator mutualisms, the plant is exclusively pollinated by an insect whose larvae are specific seed predators. Hence, outcomes of the interaction for the plant can vary with the number of eggs laid and the number of seeds eaten per larva. 2. In the work reported here, predation by Chiastocheta larvae on seeds of Trollius europaeus was analysed as a function of the number of eggs laid on the flower. Flowers with an increasing number of eggs were bagged in three populations and seeds were counted after the end of larval predation, in order to assess whether there was competition among larvae. 3. Seed predation on single‐egg flowers was high and variable (mean per population ranging from 15 to 40% of the developed seeds). Seed predation increased weakly with increasing egg load and was lower than gross seed production (always < 85%) whatever the number of eggs laid. This corresponds to a strong decrease in seed consumption per larva with increasing egg load, i.e. severe larval competition for resources. 4. The results suggest that both interference among Chiastocheta larvae and carpel dehiscence may protect T. europaeus seeds from total predation. Estimates of seed predation based on egg load observed in 20 natural populations in the French Alps typically ranged from 30 to 60%. The interaction was always beneficial for the plant and there was no risk of total seed destruction by Chiastocheta larvae, favouring stability of the mutualism.     

The influence of host plant genotype on variation in population densities of the gorse thrips,Sericothrips staphylinus (Thysanoptera: Thripidae), and its consideration in relation to release strategies

Large variations in population densities of Sericothrips staphylinus were observed between gorse bushes at a field site in an earlier Tasmanian study. A replicated potted plant experiment was conducted to assess whether genetic variation between gorse bushes could affect densities of S. staphylinus. There were significant differences in the number of S. staphylinus recovered from the individual bushes sampled within sites and individual bushes across all sites. This provides evidence that genetic variation between gorse bushes is at least partly responsible for the observed variability in field populations. The result validates the current release strategy used for the field establishment of S. staphylinus in south-eastern Australia. This strategy involves making multiple small releases (ca. 250 adults per bush per site) instead of a small number of large releases (ca. 1000 per bush per site), thereby reducing variation in numbers due to genetic affects. Genetic variation between individual plants of the same species and associated effects on herbivore densities should be considered when devising release strategies for biological control agents.     

秋家蝇对两种卫矛植物的趋性

卫矛是常见的绿化植物,而秋家蝇Musca autumnalis De Geer是畜牧业的重要昆虫。在室内利用Y型嗅觉仪对欧洲卫矛Euonymus europaeus和胶东卫矛E. kiautschovicus气味对秋家蝇Musca autumnalis De Geer的引诱效果进行了研究。结果表明：两种植物都对秋家蝇的雌性成虫有引诱作用,而欧洲卫矛引诱效果更好。进一步对叶和花的气味进行的观察表明,卫矛吸引秋家蝇主要依靠花的气味,但叶的气味也有一定的吸引作用; 叶的气味对花的引诱效果有增效作用。利用几种试剂（水、乙醇和正己烷）对欧洲卫矛花的气味物质进行了抽提,测试结果表明水或乙醇抽提物比正己烷抽提物引诱效果更好; 冷冻花与新鲜花的引诱效果没有显著的差异。     

Reconstructing the spread of invasive plants: taking into account biases associated with herbarium specimens

Aim To reconstruct the spread of invasive wetland species using herbarium specimens and to develop a method that accounts for the biases associated with this type of historical record. Location Southern Québec. Methods The temporal and spatial distribution of herbarium specimens of vascular plants was examined. Six invasive species that are mainly found in wetlands were compared with five native, non‐expanding hydrophytes. The cumulative number of locations was plotted against time to construct invasion curves. For native species, this ‘invasion curve’ indicates the spatiotemporal distribution of the sampling for herbarium specimens of wetland plants. It also represents the history of the state of knowledge of the distribution of native species. Deviation from the native species invasion curve can be used to describe the spread of invasive species. For every year on record, the cumulative number of locations of each exotic species was divided by the cumulative number of locations of all native species, and the proportions obtained were plotted against time. Periods of invasiveness were then delineated. Results During the twentieth century, two periods of intensive herbarium specimen collection in Québec can be clearly distinguished, i.e. from 1930 to 1940 and from 1950 to 1985. Several periods of invasiveness were delineated for Butomus umbellatus L. (1922–35), Hydrocharis morsus‐ranae L. (1957–96), Lycopus europaeus L. (1963–2000), Lythrum salicaria L. (1890–1905, 1923–46), Phragmites australis (Cav.) Trin. ex Steudel (1963–84) and Rorippa amphibia (L.) Bess. (1929–34, 1943–52, 1971–79). Main conclusions Accounting for sampling biases associated with herbarium specimens is important in order to objectively delineate periods of invasiveness for exotic species. The spread of wetland vascular plant species can be reconstructed using herbarium specimens, even when the phenomenon is rapid, but the reconstruction is certainly more accurate when the invasion occurred during an active sampling period. The highly variable sampling effort for herbarium specimens in Québec and in other regions strongly cautions against using herbarium data without correction procedures.     

Comparative phylogeography of mutualists and the effect of the host on the genetic structure of its partners

Whether or not species participating in specialized and obligate interactions display similar and simultaneous demographic variations at the intraspecific level remains an open question in phylogeography. In the present study, we used the mutualistic nursery pollination occurring between the European globeflower Trollius europaeus and its specialized pollinators in the genus Chiastocheta as a case study. Explicitly, we investigated if the phylogeographies of the pollinating flies are significantly different from the expectation under a scenario of plant–insect congruence. Based on a large‐scale sampling, we first used mitochondrial data to infer the phylogeographical histories of each fly species. Then, we defined phylogeographical scenarios of congruence with the plant history, and used maximum likelihood and Bayesian approaches to test for plant–insect phylogeographical congruence for the three Chiastocheta species. We show that the phylogeographical histories of the three fly species differ. Only Chiastocheta lophota and Chiastocheta dentifera display strong spatial genetic structures, which do not appear to be statistically different from those expected under scenarios of phylogeographical congruence with the plant. The results of the present study indicate that the fly species responded in independent and different ways to shared evolutionary forces, displaying varying levels of congruence with the plant genetic structure. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 1021–1035.     

Towards a Characterization of the Locomotor Activity Rhythm of the Supralittoral Isopod Tylos europaeus

Freshly collected samples of Tylos europaeus from Korba beach (northeast of Tunisia) were housed in an environmental cabinet at controlled temperature (18°C?±?.5°C) and photoperiod. Locomotor activity was recorded under two photoperiodic regimens by infrared actography every 20?min by multichannel data loggers. One regimen simulated the natural light-dark cycle on the day of collection, whereas the second imposed a state of continuous darkness on all individuals. Under entraining conditions, the animals displayed rhythmic activity, in phase with the period of darkness, whereas in continuous darkness these isopods exhibited a strong endogenous rhythm with circadian and semidiurnal components at mean periods of τ (h:min)?=?25:09?±?01:02?h and τ?=?12:32?±?00:26?h, respectively. Under free-running conditions, this endogenous rhythm showed significant intraspecific variability. (Author correspondence: bohli.dhouha@gmail.com)