Effects of fertilization and elevated CO<Subscript>2</Subscript> on larval food and butterfly nectar amino acid preference in<Emphasis Type="Italic"> Coenonympha pamphilus</Emphasis> L.

The effects of larval diet on the nutritional preferences of butterflies has rarely been examined. This study investigates whether alterations in the larval diet result in changes in adult preferences for nectar amino acids. Larvae of Coenonympha pamphilus were raised on fertilized or unfertilized Festuca rubra, grown under ambient (350 ppm) or elevated (750 ppm) atmospheric CO ₂environments. Fertilization led to marked increases in leaf nitrogen concentration. In plants grown under elevated CO ₂conditions, leaf water and nitrogen concentrations were significantly lower, and the C/N-ratio increased significantly. Fertilization of the host plant shortened the development time of C. pamphilus larvae, and pupal weight increased. In contrast, larvae of C. pamphilus developed significantly slower on F. rubra grown under elevated CO ₂, but adult emergence weight was not affected by CO ₂treatment of the plant. C. pamphilus females showed a clear preference for nectar mimics containing amino acids, whereas males, regardless of treatment, either preferred the nectar mimic void of amino acids or showed no preference for the different solutions. Female butterflies raised on fertilized plants showed a significant decline in their preference for nectar mimics containing amino acids. A slight, but not significant, trend towards increased nectar amino acid preference was found in females raised on plants grown under elevated CO ₂. We clearly demonstrate that alterations in larval host quality led to changes in butterfly nectar preferences. The ability of the butterfly to either rely less on nectar uptake or compensate for poor larval conditions represents a trade-off between larval and adult butterfly feeding.     

Estimating the complexity of bird song by using capture-recapture approaches from community ecology

Repertoire size, the number of unique song or syllable types in the repertoire, is a widely used measure of song complexity in birds, but it is difficult to calculate this exactly in species with large repertoires. A new method of repertoire size estimation applies species richness estimation procedures from community ecology, but such capture-recapture approaches have not been much tested. Here, we establish standardized sampling schemes and estimation procedures using capture-recapture models for syllable repertoires from 18 bird species, and suggest how these may be used to tackle problems of repertoire estimation. Different models, with different assumptions regarding the heterogeneity of the use of syllable types, performed best for different species with different song organizations. For most species, models assuming heterogeneous probability of occurrence of syllables (so-called detection probability) were selected due to the presence of both rare and frequent syllables. Capture-recapture estimates of syllable repertoire size from our small sample did not differ significantly from previous estimates using larger samples of count data. However, the enumeration of syllables in 15 songs yielded significantly lower estimates than previous reports. Hence, heterogeneity in detection probability of syllables should be addressed when estimating repertoire size. This is neglected using simple enumeration procedures, but is taken into account when repertoire size is estimated by appropriate capture-recapture models adjusted for species-specific song organization characteristics. We suggest that such approaches, in combination with standardized sampling, should be applied in species with potentially large repertoire size. On the other hand, in species with small repertoire size and homogenous syllable usage, enumerations may be satisfactory. Although researchers often use repertoire size as a measure of song complexity, listeners to songs are unlikely to count entire repertoires and they may rely on other cues, such as syllable detection probability.Communicated by A. Cockburn     

Relationships between metal concentrations in great tit nestlings and their environment and food

Metal concentrations (Ag, As, Cd, Cu, Hg, Ni, Pb, Zn) were determined in the feathers and excreta of nestling great tits (Parus major), in their main invertebrate prey (Lepidoptera larvae) and in vegetation samples, all collected from four sites along a pollution gradient. Metal contamination in vegetation samples increased significantly towards the pollution source. The Ag, As, Hg, Ni and Pb concentrations in food samples were significantly higher at the site closest to the pollution source compared to the other three sites. Great tit nestlings from the site closest to the pollution source had significantly higher concentrations of Ag, As, Hg and Pb in their excreta than did nestlings at the other three sites. For five metals (Ag, As, Cu, Ni and Pb), we found concentrations in caterpillars to be significantly positively correlated with vegetation samples. We also found clear significant positive correlations between excreta and caterpillars for Ag, As, Hg and Pb and between feathers and caterpillars for As and Pb. Our data suggest that excreta are a good monitor for the presence and concentrations of non-essential metals in the food and the environment of passerine birds.     

Individual PCBs as predictors for concentrations of non and mono-ortho PCBs in human milk

32 Dutch human milk samples were analyzed for PCBs with either HRGC-ECD or HRGC-LRMS in the NCI mode. Samples were collected from three different locations in The Netherlands: Amsterdam, Rotterdam and Groningen. Quantitatively, no differences could be observed between the three localities, while in addition the congener specific pattern showed a striking similarity for all individual samples. Only principal component analysis revealed slight individual differences. Based on similarities in the PCB profiles, linear relationships were calculated between 2,3′4,4′,5-PnCB (#118) or 2,2′4,4′5,5′HxCB (#153) and the most relevantnon andmonoortho PCBs exhibiting dioxinlike activity. These PCBs included 2,3,3′,4,4′-PnCB (#105), 3,3′,4,4′5-PnCB (#126) 2,3,3′,4,4′,5-HxCB (#156), 2,3,3′,4,4′,5′-HxCB (#157), 2,3′,4,4′,5,5′-HxCB (#167) and 3,3′,4,4′,5′5-HxCB (#169). Good linear relationships were observed between individual PCBs. Based on the results of this study, PCB #118 can be used to predict concentrations of the PCBs #105 and #126. PCB #153 can be used as a predictor for the PCBs #156, #157, #167 and #169, but also for the total toxic equivalencies (TEQs) ofnon andmonoortho PCBs present in human milk. This method using certain PCBs as predictors for other toxicological relevant congeners, can be useful and cost effective, e.g. for epidemiological studies. However, before applied a number of conditions should be met. These are:

1. A stable composition of the PCB matrix should be established.
2. A possible time dependent change in composition of the matrix should first be excluded when used over different time periods.

     

Nutritional correlates and mate acquisition role of multiple sexual traits in male collared flycatchers

The information content of a sexual signal may predict its importance in a multiple signal system. Many studies have correlated sexual signal expression with the absolute levels of nutrient reserves. In contrast, the changes of nutrient reserves associated with signal expression are largely unknown in the wild due to technical limitations although they are important determinants of signal information content. We compared two visual and eight acoustic sexual traits in male collared flycatchers to see whether the nutritional correlates of expression predict the role of the signal in sexual selection. We used single point assays of plasma lipid metabolites to estimate short-term changes in nutritional state in relation to sexual trait expression during courtship. As a measure of sexual selection, we estimated the relationship with pairing latency after arrival in a 4-year dataset. Males which found a mate rapidly were characterized by large wing and forehead patches, but small song strophe complexity and small figure repertoire size. Traits more strongly related to pairing latency were also more closely related to changes in nutrient reserves. This indicates a link between signal role and information content. Small wing patches and, surprisingly, complex songs seemed to indicate poor phenotypic quality and were apparently disfavoured at mate acquisition in our population. Future studies of the information content of sexual traits, especially dynamic traits such as song, may benefit from the use of plasma metabolite profiles as non-invasive indicators of short-term changes in body condition.     

Temperament in bullheads: do laboratory and field explorative behaviour variables correlate?

The relevance of temperament traits for life history strategy or productivity is increasingly acknowledged. Temperament traits are often either observed in captivity or in the wild, but studies combining both observations are very rare. We examine whether exploratory behaviour in the bullhead (Cottus perifretum), assayed under laboratory conditions, predicts this behaviour under field conditions. Forty-three PIT-tagged individuals were first assayed for exploration of a novel environment in the aquarium and then released into an unfamiliar stream stretch, where they were later relocated using a mobile antenna. Explorative behaviour assayed in the laboratory was significantly positively related to the exploration in the field, thus predicting distance moved in the field release. Both in the laboratory and in the field, explorative behaviour was not related to individual body length. When bullheads that did not leave the refuge in the aquarium (laboratory assay) and, therefore, did not explore the new environment were excluded from the analysis, the correlation between laboratory and field explorative behaviour variables became weaker. However, overall, our results illustrate that exploration rate of bullheads in isolated single-individual experiments can be used to predict this behaviour in the natural ecosystem.     

Multiple-criteria decision-aiding framework to analyze and assess the governance of sustainability

Past and present disasters and scandals, such as the BP Deepwater Horizon oil disaster in the Gulf of Mexico in 2010, the Servier Mediator (Benfluorex) scandal in 2009 and the Enron collapse in 2001, have uncovered weaknesses in governance issues. The authors argue that there is a need to develop methods and tools to diagnose and assess the governance of organizations with respect to Sustainable Development (SD). However, this task remains difficult due to the fact that it is difficult to appraise the quality of governance. The authors propose a protocol to diagnose and analyze the governance of SD and explore the use of multiple-criteria decision-aiding methods to achieve this task. Two aggregation methods to assess the global governance are proposed: (1) The identification of a final governance index for an Organization. This method helps in establishing a global diagnosis of the quality of the governance of an Organization with respect to SD challenges. The governance index is based on the calculation of three indexes: the partial opportunity index, the partial risk index and the partial equilibrium index. (2) The ranking of a set of Organizations according to their governance of SD. This method aims at assessing a set of Organizations based on a pairwise comparison according to a set of criteria that represents the seven domains of the ISO 26000 norm (ISO 26000—Guidance on social responsibility, 2010). This method is based on the outranking aggregation approach ELECTRE III. A practical example is used to illustrate two methods of governance assessment.     

Variation, levels and profiles of organochlorines and brominated flame retardants in great tit (Parus major) eggs from different types of sampling locations in Flanders (Belgium)

Small-scale geographical variation in the occurrence of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) was investigated using the eggs of a terrestrial residential songbird species, the great tit (Parus major). In addition, we investigated the influence of the type of sampling location on the presence of these pollutants. To achieve this, 10 different sampling locations in Flanders (Belgium) were classified into 3 groups based on the extent of urbanisation, industrialisation and agriculture. The higher variance among sampling locations for the levels and profiles of PCBs and OCPs, suggests that local contamination sources are more important for the PCBs and OCPs compared to the PBDEs. Levels of PCBs and PBDEs were significantly higher in the industrialised sampling locations compared to the other locations. Sum PCB and sum PBDE levels reached up to 6050 and 79 ng/g lipid weight, respectively. PCBs and PBDEs were highly positively correlated for all groups, suggesting similar exposure pathways and/or mechanisms of accumulation. Significantly higher levels of OCPs (sum OCPs up to 2683 ng/g lipid weight) were detected in the rural sampling locations situated in a residential area. This suggests that local historical usage of OCPs by inhabitants may be an important source of contamination in Flanders. Contamination profiles differed also among the sampling locations. The rural sampling locations had a higher contribution of lower brominated BDE congeners, whereas the industrialised locations had a higher contribution of higher brominated congeners. The differences in contamination profiles among the sampling locations are probably due to differences in exposure. In conclusion, our results showed that the characteristics of a sampling location influence both the levels and profiles of PCBs, OCPs and PBDEs.     

Preen oil as the main source of external contamination with organic pollutants onto feathers of the common magpie (Pica pica)

We investigated the possible sources of contamination with organic pollutants, such as polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyltrichloroethane (DDT) and metabolites, and polybrominated diphenyl ethers (PBDEs), in and onto tail feathers of a large songbird, the common magpie (Pica pica). Although feathers are potentially useful as a non-destructive biomonitor for organic pollutants, concentrations may be influenced by external contamination onto the feather surface. In a first approach, a group of magpies was captured after the completion of moult. The third tail feather was pulled out and a blood sample was taken. Most PCBs, DDTs and some PBDEs could be quantified in one single tail feather, indicating that the applicability of feathers goes beyond monitoring with predatory birds, as shown previously. Nevertheless, correlations between levels in serum and feathers were found significant in three cases only (i.e. CB 170, CB 180 and CB 187). This finding may be attributed to different factors, such as varying diet, condition, sample size or external contamination. In a second approach, cadavers of magpies were collected throughout Flanders. The preen gland was removed and the first, third and fifth tail feathers were pulled out at both sides. No significant differences were found among tail feathers within an individual. We compared three washing procedures to remove external contamination with organic pollutants from these feathers: deionised water, acetone and a surfactant/acetone solution. Right feathers were washed and left feathers were kept as control. Concentrations in the resulting washes were found highest in the acetone solutions. Furthermore, feathers washed with acetone or with a surfactant/acetone solution had significantly lower mean concentrations than the control feathers. Highest correlations with levels in preen gland were obtained for the control feathers. Consequently, the source of external contamination with organic pollutants onto feathers seems to be endogenous, originating from the preen gland. This is in great contrast to the extensive airborne pollution that has been reported for most heavy metals. In summary, the results of the current study highlight the usefulness of feathers for non-destructive biomonitoring of organic pollutants.