Establishment of a Cross-European Field Site Network in the ALARM Project for Assessing Large-Scale Changes in Biodiversity

The field site network (FSN) plays a central role in conducting joint research within all Assessing Large-scale Risks for biodiversity with tested Methods (ALARM) modules and provides a mechanism for integrating research on different topics in ALARM on the same site for measuring multiple impacts on biodiversity. The network covers most European climates and biogeographic regions, from Mediterranean through central European and boreal to subarctic. The project links databases with the European-wide field site network FSN, including geographic information system (GIS)-based information to characterise the test location for ALARM researchers for joint on-site research. Maps are provided in a standardised way and merged with other site-specific information. The application of GIS for these field sites and the information management promotes the use of the FSN for research and to disseminate the results. We conclude that ALARM FSN sites together with other research sites in Europe jointly could be used as a future backbone for research proposals

Grassland leafhoppers (Hemiptera: Auchenorrhyncha) as indicators of habitat condition - a comparison of between-site and between-year differences in assemblage composition

The Auchenorrhyncha (leafhoppers) show great potential as indicators of grassland habitat quality, which would make them useful as a conservation tool. However, they are known to have labile populations. The relative importance of site identity and the year of sampling in the composition of leafhopper assemblages on chalk grassland are assessed for two sets of sites sampled twice. The study included a total of 95 sites (one set of 54, the other of 41), and demonstrated that for both sets the vegetation community and geographical location had high explanatory value, while the influence of year was small. The conclusion is that, notwithstanding population fluctuations, the leafhopper assemblages are a good indicator of habitat quality, and represent a potentially valuable tool in grassland conservation and restoration.

Production and metabolic effects of site of starch digestion in lactating dairy cattle

Milk solids yield in modern dairy cows has increased linearly over the last 50 years, stressing the need for maximal dietary energy intake to allow genetic potential for milk energy yield to be realized with minimal negative effects on health and reproduction. Feeding supplemental starch is a common approach for increasing the energy density of the ration and supplying carbon for meeting the substantial glucose requirement of the higher yielding cow. In this regard, it is a long held belief that feeding starch in forms that increase digestion in the small intestine and glucose absorption will benefit the cow in terms of energetic efficiency and production response, but data supporting this dogma are equivocal. This review will consider the impact of supplemental starch and site of starch digestion on metabolic and production responses of lactating dairy cows, including effects on feed intake, milk yield and composition, nutrient partitioning, the capacity of the small intestine for starch digestion, and nutrient absorption and metabolism by the splanchnic tissues (the portal-drained viscera and liver). Whilst there appears to be considerable capacity for starch digestion and glucose absorption in the lactating dairy cow, numerous strategic studies implementing postruminal starch or glucose infusions have observed increases in milk yield, but decreased milk fat concentration such that there is little effect on milk energy yield, even in early lactation. Measurements of energy balance confirm that the majority of the supplemental energy arising from postruminal starch digestion is used with high efficiency to support body adipose and protein retention, even in early lactation. These responses may be mediated by changes in insulin status, and be beneficial to the cow in terms of reproductive success and well-being. However, shifting starch digestion from the rumen impacts the nitrogen economy of the cow as well by shifting the microbial protein gained from starch digestion from potentially absorbable protein to endogenous faecal loss.

Predators of Spotted Flycatcher Muscicapa striata nests in southern England as determined by digital nest cameras

Capsule Avian predators are principally responsible. Aims To document the fate of Spotted Flycatcher nests and to identify the species responsible for nest predation. Methods During 2005-06, purpose-built, remote, digital nest-cameras were deployed at 65 out of 141 Spotted Flycatcher nests monitored in two study areas, one in south Devon and the second on the border of Bedfordshire and Cambridgeshire. Results Of the 141 nests monitored, 90 were successful (non-camera nests, 49 out of 76 successful, camera nests, 41 out of 65). Fate was determined for 63 of the 65 nests monitored by camera, with 20 predation events documented, all of which occurred during daylight hours. Avian predators carried out 17 of the 20 predations, with the principal nest predator identified as Eurasian Jay Garrulus glandarius. The only mammal recorded predating nests was the Domestic Cat Felis catus, the study therefore providing no evidence that Grey Squirrels Sciurus carolinensis are an important predator of Spotted Flycatcher nests. There was no evidence of differences in nest survival rates at nests with and without cameras. Nest remains following predation events gave little clue as to the identity of the predator species responsible. Conclusions Nest-cameras can be useful tools in the identification of nest predators, and may be deployed with no subsequent effect on nest survival. The majority of predation of Spotted Flycatcher nests in this study was by avian predators, principally the Jay. There was little evidence of predation by mammalian predators. Identification of specific nest predators enhances studies of breeding productivity and predation risk.

The impact of Rhinanthus minor in newly established meadows on a productive site

Question: What is the impact of the presence of Rhinanthus minor on forb abundance in newly established swards? Location: Wetherby, West Yorkshire, UK (53 degrees 55' N, 1 degrees 22(1) W). Method: A standard meadow mix containing six forbs and six grasses was sown on an ex-arable field and immediately over-sown using a randomised plot design with three densities of Rhinanthus minor (0, 600, and 1000 seeds per m(2)). Above-ground biomass was analysed over a period of three years, while detailed assessments of sward composition were performed during the first two years. Results: Values of grass biomass were reduced in the presence of Rhinanthus, especially at the higher sowing density. The ratio of grass: forb biomass was also lower in association with Rhinanthus, but only at the higher sowing density. The presence of Rhinanthus, had no effect on species number or diversity, which decreased between years regardless of treatment. Conclusions: Although not tested in a multi-site experiment, the benefit of introducing Rhinanthus into newly established swards to promote for abundance was determined. The efficacy of Rhinanthus presence is likely to depend on whether species not susceptible to the effects of parasitism are present.

Nest spacing and breeding performance in Short-toed Eagle Circaetus gallicus in northeast Greece

Aims: To describe the phenology and breeding success of one of the densest populations of Short-toed Eagle in Europe. Methods All nests in the Dadia-Lefkimi-Soufli forest in northeast Greece were located and visited regularly throughout the 1996-98 breeding seasons. Data on every stage of the breeding cycle were collected and related to among-year variation in the weather conditions during March to June. Results: A total of 58 pairs were located during the three-year study spread across 22 territories (the same territories are usually occupied each year). The nests were evenly spaced (mean of 2.7 km between nests). Adults arrived between mid-March and mid-April. Only one egg per nest was laid. Nestlings fledged on average after 68.9 days. Eagles departed between 8 September and 2 October. Conclusions: Arrival date determines laying date. The population size appears to be stable but the species has a relatively low reproductive rate and takes three to four years to mature, consequently it may be susceptible to stochastic or human-mediated factors.

Pharmacological characterisation of the agonist radioligand binding site of 5-HT2A, 5-HT2B and 5-HT2C receptors

In the present study we compared the affinity of various drugs for the high affinity "agonist-preferring" binding site of human recombinant 5-HT2A, 5-HT2B and 5-HT2C receptors stably expressed in monoclonal mammalian cell lines. To ensure that the "agonist-preferring" conformation of the receptor was preferentially labelled in competition binding experiments, saturation analysis was conducted using antagonist and agonist radiolabels at each receptor. Antagonist radiolabels ([H-3]-ketanserin for 5-HT2A receptor and [H-3]-mesulergine for 5-HT2B and 5-HT2C receptor) bound to a larger population of receptors in each preparation than the corresponding agonist radiolabel ([I-125]-DOI for 5-HT2A receptor binding and [H-3]-5-HT for 5-HT2B and 5-HT2C receptor binding). Competition experiments were subsequently conducted against appropriate concentrations of the agonist radiolabels bound to the "agonist-preferring" subset of receptors in each preparation. These studies confirmed that there are a number of highly selective antagonists available to investigate 5-HT2 receptor subtype function (for example, MDL 100907, RS-127445 and RS-102221 for 5-HT2A, 5-HT2B and 5-HT2C receptors respectively). There remains, however, a lack of highly selective agonists. (-)DOI is potent and moderately selective for 5-HT2A receptors, BW723C86 has poor selectivity for human 5-HT2B receptors, while Org 37684 and VER-3323 display some selectivity for the 5-HT2C receptor. We report for the first time in a single study, the selectivity of numerous serotonergic drugs for 5-HT2 receptors from the same species, in mammalian cell lines and using, exclusively, agonist radiolabels. The results indicate the importance of defining the selectivity of pharmacological tools, which may have been over-estimated in the past, and highlights the need to find more selective agonists to investigate 5-HT2 receptor pharmacology.

Analysis of the antigen combining site: Correlations between length and sequence composition of the hypervariable loops and the nature of the antigen

It has long been suggested that the overall shape of the antigen combining site (ACS) of antibodies is correlated with the nature of the antigen. For example, deep pockets are characteristic of antibodies that bind haptens, grooves indicate peptide binders, while antibodies that bind to proteins have relatively flat combining sites. In. 1996, MacCallum, Martin and Thornton used a fractal shape descriptor and showed a strong correlation of the shape of the binding region with the general nature of the antigen. However, the shape of the ACS is determined primarily by the lengths of the six complementarity-determining regions (CDRs). Here, we make a direct correlation between the lengths of the CDRs and the nature of the antigen. In addition, we show significant differences in the residue composition of the CDRs of antibodies that bind to different antigen classes. As well as helping us to understand the process of antigen recognition, autoimmune disease and cross-reactivity these results are of direct application in the design of antibody phage libraries and modification of affinity. (C) 2003 Elsevier Science Ltd. All rights reserved.

Dung and nest surveys: estimating decay rates

1. Wildlife managers often require estimates of abundance. Direct methods of estimation are often impractical, especially in closed-forest environments, so indirect methods such as dung or nest surveys are increasingly popular. 2. Dung and nest surveys typically have three elements: surveys to estimate abundance of the dung or nests; experiments to estimate the production (defecation or nest construction) rate; and experiments to estimate the decay or disappearance rate. The last of these is usually the most problematic, and was the subject of this study. 3. The design of experiments to allow robust estimation of mean time to decay was addressed. In most studies to date, dung or nests have been monitored until they disappear. Instead, we advocate that fresh dung or nests are located, with a single follow-up visit to establish whether the dung or nest is still present or has decayed. 4. Logistic regression was used to estimate probability of decay as a function of time, and possibly of other covariates. Mean time to decay was estimated from this function. 5. Synthesis and applications. Effective management of mammal populations usually requires reliable abundance estimates. The difficulty in estimating abundance of mammals in forest environments has increasingly led to the use of indirect survey methods, in which abundance of sign, usually dung (e.g. deer, antelope and elephants) or nests (e.g. apes), is estimated. Given estimated rates of sign production and decay, sign abundance estimates can be converted to estimates of animal abundance. Decay rates typically vary according to season, weather, habitat, diet and many other factors, making reliable estimation of mean time to decay of signs present at the time of the survey problematic. We emphasize the need for retrospective rather than prospective rates, propose a strategy for survey design, and provide analysis methods for estimating retrospective rates.

Conformational and hydration effects of site-selective sodium, calcium and strontium ion binding to the DNA Holliday junction structure d(TCGGTACCGA)(4)

The role of metal ions in determining the solution conformation of the Holliday junction is well established, but to date the picture of metal ion binding from structural studies of the four-way DNA junction is very incomplete. Here we present two refined structures of the Holliday junction formed by the sequence d(TCGGTACCGA) in the presence of Na+ and Ca2+, and separately with Sr2+ to resolutions of 1.85 Angstrom and 1.65 Angstrom, respectively. This sequence includes the ACC core found to promote spontaneous junction formation, but its structure has not previously been reported. Almost complete hydration spheres can be defined for each metal cation. The Na+ sites, the most convincing observation of such sites in junctions to date, are one on either face of the junction crossover region, and stabilise the ordered hydration inside the junction arms. The four Ca2+ sites in the same structure are at the CG/CG steps in the minor groove. The Sr2+ ions occupy the TC/AG, GG/CC, and TA/TA sites in the minor groove, giving ten positions forming two spines of ions, spiralling through the minor grooves within each arm of the stacked-X structure. The two structures were solved in the two different C2 lattices previously observed, with the Sr2+ derivative crystallising in the more highly symmetrical form with two-fold symmetry at its centre. Both structures show an opening of the minor groove face of the junction of 8.4degrees in the Ca2+ and Na+ containing structure, and 13.4degrees in the Sr2+ containing structure. The crossover angles at the junction are 39.3degrees and 43.3degrees, respectively. In addition to this, a relative shift in the base pair stack alignment of the arms of 2.3 Angstrom is observed for the Sr2+ containing structure only. Overall these results provide an insight into the so-far elusive stabilising ion structure for the DNA Holliday junction. (C) 2003 Elsevier Science Ltd. All rights reserved.