The Effect of Price and Socio-Economic Level on the Consumption of Sugar-Sweetened Beverages (SSB): The Case of Ecuador

The objective of this article is to estimate the own-price, cross-price and income elasticities of demand for SSB in Ecuador, as an indispensable step for predicting a reduction in the consumption of said beverages caused by the potential implementation of taxes in Ecuador. In addition, the own-price, cross-price and income elasticities of sugar-free substitutes like mineral water and diet soft drinks and juices are also estimated. The data from the 2011–2012 ENIGHUR, which contains detailed information on household consumption and socioeconomic variables, was used. The estimates are done using Deaton’s Almost Ideal Demand System (AIDS) which accounts for differences in the quality of goods purchased. This demand system is estimated for different socio-economic groups, according to total household expenditure. The results reveal own-price elasticities for SSB between –1.17 and –1.33 depending on the socio-economic group, in line with the existing evidence for developed countries. Own-price elasticity for non-SSB is between -1 and -1.24. Income elasticities reveal that both SSB and non-SSB are normal goods with elasticities decreasing for higher socio-economic groups. These results show that the consumption of SSB is sensitive to price changes, meaning that the implementation of taxes on said beverages could be effective in reducing their consumption. The fact that non-SSB are also sensitive to price changes would indicate that subsidies could be implemented for the production of some of them.     

How Well do Foragers Protect Food Consumption? Panel Evidence from a Native Amazonian Society in Bolivia

The ability of rural people to protect their food consumption matters because it captures their economic vulnerability. How well do foragers protect consumption from adverse income shocks and does protection work equally well for all people in the household? We answer the queries with data from 156 adults and 169 children collected over five consecutive quarters from the Tsimane’, a native Amazonian society of foragers and farmers in Bolivia. We estimate whether quarterly changes in the logarithm of consumption bear an association with quarterly changes in the logarithm of cash income while controlling for many confounders, including covariant shocks. We use anthropometric indices of short-run nutritional status to proxy for food consumption and use instrumental variables to abate biases from the endogeneity of income. We found that child consumption was fully protected from income growth, but adult consumption was not as well protected. Estimates of income elasticities of consumption fell toward the lower range of estimates from previous studies of farming and industrial societies. We present several hypotheses to explain how the Tsimane’ smooth consumption.     

A theoretical comparison of the consumer surplus and the elasticities of demand as measures of motivational strength

The price and income elasticities of demand have been used by ethologists to estimate motivational strength. The consumer surplus is an alternative measure of motivation, deriving from microeconomic theory. We made a theoretical assessment of the validity and versatility of these indices. Two factors are expected to compromise the internal validity (veracity) of the elasticity of demand indices: failure to take into account the amount that an animal is required to pay to maintain some level of consumption; and a tendency to confuse its readiness to defend a preferred consumption level with a propensity to become satiated. A third factor, expected to compromise the external validity (usefulness) of these indices, is the unrealistic assumption that a single value can be assigned to each resource. None of these problems applies to the consumer surplus index. One further factor, expected to compromise the internal validity of both the consumer surplus and price elasticity indices, is their failure to account for the effects that income has upon consumption. Overall, we conclude that the consumer surplus should be more valid, both internally and externally, than the price elasticity index. The consumer surplus should also be more externally valid than the income elasticity index, but it is unclear, on balance, which of these indices is the more internally valid. Finally, we show that both elasticity indices are considerably less versatile than the consumer surplus, owing to the assumption that a single value can be assigned to each resource. Copyright 2003 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.      

More or Better? A Model for Changes in Household Greenhouse Gas Emissions due to Higher Income

Households exert an important influence on total greenhouse gas (GHG) emissions. Therefore, their consumption behavior is of interest in evaluations of climate policy options and projections of future emission paths. While most evaluations of household consumption and its emissions are based on expenditure only, we use a household consumption model based on functional units (e.g., kg food, person kilometers, living square meters). The goal of this article is to assess changes in consumption with increasing affluence level of households and to compare the allocation of GHG emissions to monetary versus functional units. We find that (1) the model based on functional units provides good bottom-up estimates for greenhouse emissions of Swiss households; (2) quality (price per functional unit) increases with income for many consumption categories, and therefore using functional instead of monetary units leads to a lower increase of greenhouse gas emissions with income; (3) the relevance of GHG emissions from goods and mobility will increase. We conclude that using household models based on monetary units only overestimates the impact of marginal consumption and neglects the potential of decoupling income and environmental impact by consuming better instead of more. For sustainable consumption, research and policy should aim at preventing goods of higher quality from having higher environmental impact in order to benefit from the increasing quality orientation with rising income.     

Estimating stochastic elasticities directly from longitudinal data

The elasticities of long-run population growth rate with respect to vital rates are useful in studying selection on vital rates, and in evaluating management policy that aims to control vital rates. In temporally varying environments, elasticity is often calculated from simulations that assume a probability distribution for the environmental states. Here we develop a method to estimate elasticities directly from demographic data. Using a time-series of demographic matrices and age-structure we construct a consistent statistical estimator of elasticity that converges to the correct limiting value as the sample length increases. We also construct confidence intervals for elasticities from temporal data and suggest tools for testing hypotheses about the strength of selection. We use data on a natural population to show that our method can indeed accurately estimate elasticities using relatively short time series.     

Growth and laccase production kinetics of <Emphasis Type="Italic">Trametes versicolor</Emphasis> in a stirred tank reactor

White rot fungi are a promising option to treat recalcitrant organic molecules, such as lignin, polycyclic aromatic hydrocarbons, and textile dyes, because of the lignin-modifying enzymes (LMEs) they secrete. Because knowledge of the kinetic parameters is important to better design and operate bioreactors to cultivate these fungi for degradation and/or to produce LME(s), these parameters were determined using Trametes versicolor ATCC 20869 (ATCC, American Type Culture Collection) in a magnetic stir bar reactor. A complete set of kinetic data has not been previously published for this culture. Higher than previously reported growth rates with high laccase production of up to 1,385 U l⁻¹ occurred during growth without or glucose limitation. The maximum specific growth rate averaged 0.94 ± 0.23 day⁻¹, whereas the maximum specific substrate consumption rates for glucose and ammonium were 3.37 ± 1.16 and 0.15 ± 0.04 day⁻¹, respectively. The maximum specific oxygen consumption rate was 1.63 ± 0.36 day⁻¹.     

Energetics of arousal episodes in hibernating arctic ground squirrels

Arctic ground squirrels overwintering in northern Alaska experience average soil temperature of −10°C. To examine energetic costs of arousing from hibernation under arctic compared to temperate conditions, captive ground squirrels were maintained in ambient temperatures (T _a) of 2, −5 and −12°C. Rates of oxygen consumption and carbon dioxide production were used to estimate metabolic rate and fuel use during the three phases of arousal episodes: rewarming, euthermia, and recooling. Respiratory quotient comparisons suggest exclusive use of lipid during rewarming and mixed fuel use during euthermia. Animals rewarming from torpor at T _a −12°C took longer, consumed more oxygen, and attained higher peak rates of oxygen consumption when compared to 2°C. T _a had no significant effect on cost or duration of the euthermic phase. Animals recooled faster at −12°C than at 2°C, but total oxygen consumption was not different. T _a had no significant effect on the total cost of arousal episodes when all three phases are included. Arousal episodes account for 86% of estimated costs of a complete hibernation cycle including torpor when at 2°C and only 23% at −12°C. Thus, due to the higher costs of steady-state metabolism during torpor, proportional metabolic costs of arousal episodes at T _a characteristic of the Arctic are diminished compared to relative costs of arousals in more temperate conditions.     

The many growth rates and elasticities of populations in random environments

Despite considerable interest in the dynamics of populations subject to temporally varying environments, alternate population growth rates and their sensitivities remain incompletely understood. For a Markovian environment, we compare and contrast the meanings of the stochastic growth rate (lambdaS), the growth rate of average population (lambdaM), the growth rate for average transition rates (lambdaA), and the growth rate of an aggregate represented by a megamatrix (shown here to equal lambdaM). We distinguish these growth rates by the averages that define them. We illustrate our results using data on an understory shrub in a hurricane-disturbed landscape, employing a range of hurricane frequencies. We demonstrate important differences among growth rates: lambdaS lambdaM. We show that stochastic elasticity, ESij, and megamatrix elasticity, EMij, describe a complex perturbation of both means and variances of rates by the same proportion. Megamatrix elasticities respond slightly and stochastic elasticities respond strongly to changing the frequency of disturbance in the habitat (in our example, the frequency of hurricanes). The elasticity EAij of lambdaA does not predict changes in the other elasticities. Because ES, although commonly utilized, is difficult to interpret, we introduce elasticities with a more direct interpretation: ESmu for perturbations of means and ESsigma for variances. We argue that a fundamental tool for studying selection pressures in varying environments is the response of growth rate to vital rates in all habitat states.     

Quadrupedal locomotor performance in two species of arboreal squirrels: predicting energy savings of gliding

Gliding allows mammals to exploit canopy habitats of old-growth forests possibly as a means to save energy. To assess costs of quadrupedal locomotion for a gliding arboreal mammal, we used open-flow respirometry and a variable-speed treadmill to measure oxygen consumption and to calculate cost of transport, excess exercise oxygen consumption, and excess post-exercise oxygen consumption for nine northern flying squirrels (Glaucomys sabrinus) and four fox squirrels (Sciurus niger). Our results indicate that oxygen consumption during exercise by flying squirrels was 1.26–1.65 times higher than predicted based on body mass, and exponentially increased with velocity (from 0.84 ± 0.03 ml O₂ kg⁻¹ s⁻¹ at 0.40 m s⁻¹ to 1.55 ± 0.03 ml O₂ kg⁻¹ s⁻¹ at 0.67 m s⁻¹). Also, cost of transport in flying squirrels increased with velocity, although excess exercise oxygen consumption and excess post-exercise oxygen consumption did not. In contrast, oxygen consumption during exercise for fox squirrels was similar to predicted, varying from 0.51 (±0.02) ml O₂ kg⁻¹ s⁻¹ at 0.63 m s⁻¹ to 0.54 (±0.03) ml O₂ kg⁻¹ s⁻¹ at 1.25 m s⁻¹. In addition, the cost of transport for fox squirrels decreased with velocity, while excess exercise oxygen consumption and excess post-exercise oxygen consumption did not. Collectively, these observations suggest that unlike fox squirrels, flying squirrels are poorly adapted to prolonged bouts of quadrupedal locomotion. The evolution of skeletal adaptations to climbing, leaping, and landing and the development of a gliding membrane likely has increased the cost of quadrupedal locomotion by >50% while resulting in energy savings during gliding and reduction in travel time between foraging patches.     

Price elasticity of the demand for sugar sweetened beverages and soft drinks in Mexico

A large and growing body of scientific evidence demonstrates that sugar drinks are harmful to health. Intake of sugar-sweetened beverages (SSB) is a risk factor for obesity and type 2 diabetes. Mexico has one of the largest per capita consumption of soft drinks worldwide and high rates of obesity and diabetes. Fiscal approaches such as taxation have been recommended as a public health policy to reduce SSB consumption. We estimated an almost ideal demand system with linear approximation for beverages and high-energy food by simultaneous equations and derived the own and cross price elasticities for soft drinks and for all SSB (soft drinks, fruit juices, fruit drinks, flavored water and energy drinks). Models were stratified by income quintile and marginality index at the municipality level. Price elasticity for soft drinks was −1.06 and −1.16 for SSB, i.e., a 10% price increase was associated with a decrease in quantity consumed of soft drinks by 10.6% and 11.6% for SSB. A price increase in soft drinks is associated with larger quantity consumed of water, milk, snacks and sugar and a decrease in the consumption of other SSB, candies and traditional snacks. The same was found for SSB except that an increase in price of SSB was associated with a decrease in snacks. Higher elasticities were found among households living in rural areas (for soft drinks), in more marginalized areas and with lower income. Implementation of a tax to soft drinks or to SSB could decrease consumption particularly among the poor. Substitutions and complementarities with other food and beverages should be evaluated to assess the potential impact on total calories consumed.     

Predicting the status of wild deer as hosts of <Emphasis Type="Italic">Mycobacterium bovis</Emphasis> infection in Britain

Control of livestock diseases can become complicated when wild animals are involved. The Eurasian badger (Meles meles) is considered the principle wildlife host of Mycobacterium bovis (which causes bovine tuberculosis, bTB) in Great Britain and Ireland, but wild deer have also been implicated. Whether wild deer are likely to perpetuate bTB in cattle depends on the exposure risks they pose, the mode of pathogen transmission, the distances over which the disease can be transported and whether they can maintain infection within their own populations independently of other sources. We evaluated the likely host status of each of four species of wild British deer (red, roe, fallow and Reeves' muntjac) and the badger across a range of densities typically observed in Britain by manipulating the reproductive number equation proposed by Anderson and May (1991). We estimate that roe deer almost certainly act as spillover hosts at densities lower than 30 km⁻², red deer below 16 km⁻², muntjac below 6 km⁻², fallow below 4 km⁻² and the badger below 2 km⁻². We also estimate that muntjac will almost certainly act as maintenance hosts at densities above 56 km⁻², fallow above 47 km⁻² and badgers above 24 km⁻². For densities between these values, we cannot be certain of the host status of these species, and for red and roe deer we cannot be certain of host status under most natural conditions typically experienced in parts of Britain experiencing high incidence of bTB in cattle. However, enhanced transmission rates resulting from artificially high densities such as might be experienced at supplementary feeding sites may be sufficient to promote independent maintenance of infection. We were not able to confidently assign host status to any species over a wide range of densities, but conclude that this is likely to reflect reality, where host status may be affected as much by, for example, demographic fluctuations as it is by population density. Our results imply densities below which populations of wild deer inhabiting cattle bTB hotspots ought to be maintained in order to control the possibility of them perpetuating the cycle of intra- and interspecific M. bovis transmission.     

Soil-mixing effects on inorganic nitrogen production and consumption in forest and shrubland soils

Soils that are physically disturbed are often reported to show net nitrification and NO₃⁻ loss. To investigate the response of soil N cycling rates to soil mixing, we assayed gross rates of mineralization, nitrification, NH₄⁺ consumption, and NO₃⁻ consumption in a suite of soils from eleven woody plant communities in Oregon, New Mexico, and Utah. Results suggest that the common response of net NO₃⁻ flux from disturbed soils is not a straightforward response of increased gross nitrification, but instead may be due to the balance of several factors. While mineralization and NH₄⁺ assimilation were higher in mixed than intact cores, NO₃⁻ consumption declined. Mean net nitrification was 0.12 mg N kg⁻¹ d⁻¹ in disturbed cores, which was significantly higher than in intact cores (−0.19 mg N kg⁻¹ d⁻¹). However, higher net nitrification rates in disturbed soils were due to the suppression of NO₃⁻ consumption, rather than an increase in nitrification. Our results suggest that at least in the short term, disturbance may significantly increase NO₃⁻ flux at the ecosystem level, and that N cycling rates measured in core studies employing mixed soils may not be representative of rates in undisturbed soils.     

Body Mass Index and Chronic Energy Deficiency Among Urban Bengalee Male Slum Dwellers of Kolkata, India: Relationship with Family Income

A cross-sectional study of 191 adult (>18 years) Bengalee male slum dwellers of Kolkata, India, was undertaken to study the relationships of family income with body mass index (BMI) and chronic energy deficiency (CED). Results revealed that the mean height, weight, and BMI of the subjects were 162.2 cm, 54.0 kg, and 20.5 kg/m², respectively. The overall frequency of CED (BMI < 18.5 kg/m²) was 33.5%. Based on the World Health Organization classification, the prevalence of CED among this population was high (20–39%) and thus the situation is serious. Overall, monthly family income (MFI) was significantly positively correlated (r = 0.18, p < 0.05) with BMI. Linear regression analyses showed that MFI had significant impact (p < 0.05) on BMI. The percent variation in BMI explained by MFI was 2.6%. Subjects belonging to the lowest family income group (FIG) had the lowest mean BMI (19.5 kg/m²) and the highest rate of CED (46.6%) while those in the highest FIG had the largest mean BMI (21.4 kg/m²) and lowest rate of CED (23.1%). There was a significant FIG difference (F = 2.965, p < 0.05) in mean BMI. Moreover, there existed FIG differences (χ ² = 7.54, p < 0.06) in CED rates. In conclusion, this study provided strong evidence that FIG was significantly associated with BMI and the presence of CED. The rate of CED was high, indicating a serious situation. These findings may have severe public health implications. It is recommended that immediate nutritional intervention programs be initiated among this population along with serious efforts to increase their family income.     

Genetic variation in basic density and modulus of elasticity of coastal Douglas-fir

Douglas-fir trees from 39 open-pollinated families at four test locations were assessed to estimate heritability of modulus of elasticity (MOE) and basic density. After trees were felled, sound velocity was measured on 4-m logs with the Director HM200. Disks were taken to estimate dry and green wood density; dynamic MOE was estimated as green density × (sound velocity)². Heritability estimates of MOE (across-site h ²=0.55) were larger than those for total height (0.15) and diameter at breast height (DBH; 0.29), and similar to those for density (0.59). Negative genetic correlations were found for MOE with height (r _A=−0.30) and DBH (r _A=−0.51), and were similar to those found for density with height (r _A=−0.52) and DBH (r _A=−0.57). The partial correlations of height with MOE and density, while holding DBH constant, were positive, implying that the observed negative correlations between height and the wood properties were a function of the high positive correlation between height and DBH and the strong negative correlations between DBH and the wood properties. Taper [DBH/(height−1.4)] was found to be negatively associated with MOE. Selection for MOE may produce greater gains than selection for density because MOE had a larger coefficient of additive variation (9.6%) than density (5.1%). Conversely, selection for growth may have a more negative impact on MOE than density because of the greater genetic variation associated with MOE. Family mean correlations of the wood quality traits with stem form and crown health were mostly nonsignificant.     

Estimation of bioavailability and potential risks of naphthalene in soils with solid phase microextraction

A series of batch experiments were conducted to observe the variations of bioavailability of naphthalene in different types of soil with indigenous microorganisms. Solid phase microextraction (SPME) was employed to estimate the bioavailability of naphthalene in the soils. Various soil properties were attained by artificially modifying soil organic matter (SOM) with the addition of bagasse compost and textures with the addition of original silt and clay to determine the correlation between the amount of biodegraded naphthalene after 300 h and the amount of extractable naphthalene by SPME. Experimental results indicated that the biodegradation rate increased from 0.30 (sandy loam) to 0.48 (silty loam) μg g⁻¹ h⁻¹ when soils had more silt/clay. In contrast, the biodegradation rate slightly decreased from 0.30 (1.3% SOM) to 0.20 (5.2% SOM) μg g⁻¹ h⁻¹ when the SOM was high. Distributions of naphthalene in soils after biodegradation were affected by the addition of bagasse compost. It showed that the bioavailability of naphthalene in soils decreased with an increase in SOM. Sequestration as measured by ultrasonic extractability evidently occurred within 4 months in aged soil samples. However, the amounts extracted by sonication after 4 and 16 months of aging did not statistically differ from each other. The SPME measurements correlated well with the amount of biodegraded naphthalene by indigenous microorganisms. Results of this study demonstrate that SPME is a promising method to estimate the bioremediation efficacy of naphthalene-contaminated soils with various properties.     

Infrequent Breakfast Consumption Is Associated with Higher Body Adiposity and Abdominal Obesity in Malaysian School-Aged Adolescents

Unhealthy dietary pattern increases the risk of obesity and metabolic disorders in growing children and adolescents. However, the way the habitual pattern of breakfast consumption influences body composition and risk of obesity in adolescents is not well defined. Thus, the aim of the present study was to assess any associations between breakfast consumption practices and body composition profiles in 236 apparently healthy adolescents aged 12 to 19 years. A self-administered questionnaire on dietary behaviour and lifestyle practices and a dietary food frequency questionnaire were used. Body composition and adiposity indices were determined using standard anthropometric measurement protocols and dual energy χ-ray absorptiometry (DXA). Mean age of the participants was 15.3±1.9 years. The majority of participants (71.2%) fell in the normal body mass index (BMI) ranges. Breakfast consumption patterns showed that only half of the participants (50%) were consuming breakfast daily. Gender-specific multivariate analyses (ANCOVA) showed that in both boys and girls, those eating breakfast at least 5 times a week had significantly lower body weight, body mass index (BMI), BMI z-scores, waist circumference, body fat mass and percent body fat (%BF) compared to infrequent breakfast eaters, after adjustment for age, household income, pubertal status, eating-out and snacking practices, daily energy intakes, and daily physical activity levels. The present findings indicate that infrequent breakfast consumption is associated with higher body adiposity and abdominal obesity. Therefore, daily breakfast consumption with healthy food choices should be encouraged in growing children and adolescents to prevent adiposity during these critical years of growth.     

Enhancement of biodesulfurization by <Emphasis Type="Italic">Pseudomonas delafieldii</Emphasis> in a ceramic microsparging aeration system

A 700 ml membrane-aerated, stirred glass reactor equipped with four vertical baffles was constructed. Biodesulfurization of model oil (n-dodecane containing dibenzothiophene—DBT) and hydrodesulfurized diesel was carried out using Pseudomonas delafieldii strain R-8. Microbubble aeration gave an activity of 1.3 mg DBT removed g⁻¹ h⁻¹ and 277 μg sulfur g⁻¹ h⁻¹ for model oil and hydrodesulfurized diesel, respectively. These values were 1.9- and 1.6-times higher than using a traditional bubble aeration process. This is a promising method for the biodesulfurization of petroleum feedstocks.     

Leaf water relations characteristics of differently potassium fertilized and watered field grown barley plants

Seasonal leaf water relations characteristics were studied in fully irrigated spring barley (Hordeum distichum L. cv. Gunnar) fertilized at low (50 kg K ha⁻¹) or high (200 kg K ha⁻¹) levels of potassium applied as KCl. The investigation was undertaken from about 14 days before anthesis until the milk ripe stage in leaves of different position and age. Additionally, the effects of severe water stress on leaf water relations were studied in the middle of the grain filling period in spring barley (cv. Alis). The leaf water relations characteristics were determined by the pressure volume (PV) technique. Water relations of fully irrigated plants were compared in leaf No 7 with the water relations of slowly droughted plants (cv. Alis). Leaf osmotic potential at full turgor (ψ _π ¹⁰⁰ ) decreased 0.1 to 0.3 MPa in droughted leaves indicating a limited osmotic adjustment due to solute accumulation. The leaf osmotic potential at zero turgor (ψ _π ⁰ ) was about −2.2 MPa in fully irrigated plants and −2.6 MPa in droughted plants. The relative water content at zero turgor (R⁰) decreased 0.1 unit in severely droughted leaves. The ratio of turgid leaf weight to dry weight (TW/DW) tended to be increased by drought. The tissue modulus of elasticity (ε) decreased in droughted plants and together with osmotic adjustment mediated turgor maintenance during drought. A similar response to drought was found in low and high K plants except that the R⁰ and ε values tended to be higher in the high K plants. Conclusively, during drought limited osmotic adjustment and increase in elasticity of the leaf tissue mediated turgor maintenance. These effects were only slightly modified by high potassium application. The seasonal analysis in fully irrigated plants (cv. Gunnar) showed that within about 14 days from leaf emergence ψ _π ¹⁰⁰ decreased from about −0.9 to −1.6 MPa in leaf No 7 (counting the first leaf to emerge as number one) and from about −1.1 to −1.9 MPa in leaf No 8 (the flag leaf) due to solute accumulation. A similar decrease took place in ψ _π ⁰ except that the level of ψ _π ⁰ was displaced to a lower level of about 0.2 to 0.3 MPa. Both ψ _π ¹⁰⁰ and ψ _π ⁰ tended to be 0.05 to 0.10 MPa lower in high K than in low K plants. R⁰ was about 0.8 to 0.9 and was independent of leaf position and age, but tended to be highest in high K plants. The TW/DW ratio decreased from about 5.5 in leaf No 6 to 4.5 in leaf No 7 and 3.8 in leaf No 8. The TW/DW ratio was 4 to 10% higher in high K than in low K plants indicating larger leaf cell size in the former. The apoplastic water content (V_a) at full turgor constituted about 15% in leaf No 7. ε was maximum at full turgor and varied from about 11 to 34 MPa. ε tended to be higher in high K plants. Conclusively, in fully watered plants an ontogenetically determined accumulation of solutes (probably organic as discussed) occurred in the leaves independent of K application. The main effect of high K application on water relations was an increase in leaf water content and a slight decrease in leaf ψ_π. The effect of K status on growth and drought resistance is discussed.     

Biotope Use and Trends of European Butterflies

Europe has undergone substantial biotope loss and change over the last century and data are needed urgently on the rate of decline in different wildlife groups in order to identify and target conservation measures. However, pan-European data are available for very few taxonomic groups, notably birds. We present here the first overview of trends for an insect group within different biotopes across Europe, based on data from the Red Data Book of European Butterflies. The most important biotopes for Europe’s 576 butterfly species, including threatened species, are man-made or man-influenced, notably types of grassland or heath/scrub communities. Our results show that butterflies are declining substantially across Europe, with a decline in distribution of −11% over the last 25 years. The distributions of the 25 most “generalist” species are declining only slowly (−1%) compared to specialist butterflies of grassland (−19%), wetlands (−15%), and forests (−14%). On average, grassland butterflies have declined somewhat slower than farmland birds (annual decrease −0.8% compared to −1.5%), but woodland butterflies have decreased more rapidly (−0.01% to −0.6%) than woodland birds, which are more or less stable. The sensitivity of butterflies to environmental changes and the availability of data across Europe suggest that they are very good candidates to build biodiversity indicators and, along with other major groups such as birds, suitable to monitor progress towards the EU target of halting biodiversity loss by 2010. An erratum to this article is available at .     

Valuation of wildlife populations above survival

Biodiversity valuation studies often address the willingness to pay (WTP) for species survival. Many policy initiatives, however, target more generally the population levels of wildlife. This study investigated the empirical question of WTP for enhancing species populations also beyond the survival level. Respondents’ WTP for increases in population levels of endangered species as well as of general wildlife in three habitats were evaluated in a choice experiment, by trading off against income tax and restrictions in recreational access. Any person may have several motives for deriving value from enhanced wildlife populations, and variation in values were analysed in a Latent Class model. We document considerable discrete variations in WTP and respondents fall into several distinct groups. The first group express a significant WTP for saving endangered species only and has no positive WTP for higher population levels, indicating that existence values dominate their WTP. The second group put emphasis on wildlife, but with equal weight attached to moderate and high increases in population for ‘Endangered’ as well as ‘General’ wildlife. Thus, they appear insensitive to scope. The pattern suggests that WTP may be affected by warm glow or deontological motivations. The third group reveal significant WTP, but for at least one of the wildlife attributes they prefer moderate increases over high. This could be due to moral motivations or reflect provision cost concerns. Our findings point to the caution needed when using results from studies focusing on species survival in valuing broader initiatives.