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Palomena prasina, the green shield bug (GSB), is widely distributed in the Eurosiberian region. In the Southwest of France, it is considered as a serious pest of hazelnuts, its feeding punctures lead to blank hazelnuts and kernel necrosis, causing heavy losses in commercial orchards. To date, no Integrated Pest Management strategy is available to control P. prasina. Control strategies often focus on the pests' spring–summer ecology, when they are in the field or in the vicinity of crops. However, the abundance of pest populations in crops is also related to their autumn‐winter ecology. The present work focussed on the autumn‐winter ecology of P. prasina to identify new opportunities for this pest suppression. We investigate (i) where P. prasina overwinters, (ii) if it aggregates in its overwintering sites and (iii) if it mates while overwintering. Samples were collected over a 2‐year period in different ecosystems (forests, hedges, orchards), in human‐made structures and habitats (litter, bushes/trees, dead trees). The reproductive status of GBS individuals was monitored in winter, and in spring when they emerged from overwintering sites. Our results show that 97% P. prasina adults overwinter in the leaf litter of orchards and natural ecosystems and that 70% overwinter individually. The abundance of GSB in those sites is negatively correlated with litter temperature and positively correlated with humidity levels. Furthermore, adults only mate after leaving their overwintering site. Finally, unexpectedly, there was an important number of overwintering adults hosting endoparasitoids (32%). The fact that GSB overwinters alone in the leaf litter means controlling its populations by destroying the overwintering sites is not a solution. All the same, our results point out some promising lines of research for developing methods to control P. prasina. First, the emergence traps, in particular the cone traps, proved efficient for collecting emerging adults and could be considered for monitoring. Moreover, our observations suggest the existence of long‐range mating signals that could be exploited for trapping. Last but not least, the important number of overwintering parasitised adults is a potential biocontrol avenue. [ABSTRACT FROM AUTHOR]

Sociality is not common among parasitoid hymenopterans, but members of the ectoparasitoid genus Sclerodermus (in the aculeate family Bethylidae) may form multi‐foundress groups, producing and tending a single brood (of combined parentage) on a large host until offspring maturity. While individual foundresses can benefit more from reproducing within groups rather than alone, recent studies have indicated that there are conflicts of interest between co‐foundresses at the time of host suppression and during brood production, some of which may be mediated by intrinsic or acquired dominance. Evidence for overtly agonistic interactions has, however, been lacking.Here, we report that resident Sclerodermus guani Xiao et Wu females that have suppressed a host, can either accept introduced intruder females as co‐foundresses without aggression or repel, and even kill, intruders by biting and stinging them.Residents were more likely to exhibit aggression when they had commenced oviposition, when more days had passed since oviposition, when they were larger than the intruder, when the intruder was a non‐sibling, or when they were the sole resident rather than being in a group of two residents.We conclude that cooperatively brooding in Sclerodermus can be conditional on the evolutionary interests of foundresses with temporal priority on a host and their ability to repel potential co‐foundresses. [ABSTRACT FROM AUTHOR]

Background: Fecal S100/calgranulin (S100A12 and calprotectin) concentrations are useful markers of gastrointestinal inflammation in dogs. In people, fecal S100/calgranulin concentrations are affected by age, obesity, diet and other lifestyle factors. Knowledge about the effects of such factors on fecal S100/calgranulin concentrations in dogs is currently scarce. Objective: To evaluate the association between several factors and fecal S100/calgranulin concentrations in a large cohort of healthy adult dogs. Methods: Single‐spot fecal samples from 181 healthy pet dogs and data derived from a standard questionnaire served to evaluate the effect of age, sex, reproductive status, body weight and body condition, breed type and size, vaccination, endoparasite treatment, diet, environment and travel history on fecal S100/calgranulin concentrations and the fecal calgranulin ratio (fCalR). Results: Univariate analysis showed a significant association of reproductive status (in female dogs) and breed size with fecal S100A12, fecal calprotectin and fCalR. Breed type was linked to fecal S100A12 concentrations and fCalR; recent vaccination (particularly with a vaccine against canine parvovirus) to fCalR. In multivariate models, breed size was linked to fecal S100A12 and calprotectin concentrations, and recent vaccination affected S100A12 concentrations. Conclusions: Breed size, recent vaccination and reproductive status in female dogs can affect fecal S100/calgranulin concentrations, and these biomarkers should be interpreted in light of those confounding factors. The utility of reference intervals for fecal canine S100/calgranulin concentrations might be improved through stratification by sex/reproductive status and breed size. Fecal canine S100/calgranulin concentrations are not confounded by age, body condition, deworming, diet, environment or travel history. [ABSTRACT FROM AUTHOR]

Once cornered by a predator, prey can try to intimidate the assailant or repel it, with irritating sprays for example. If seized, they may scratch, bite or struggle to cause the predator to release its grip. At the other extreme, they can adopt passive behaviours such as death feigning (DF, i.e. thanatosis). DF is observed widely across the animal kingdom; it usually involves a combination of displays such as immobility, supination, leg‐folding, mouth opening and release of nauseating secretions. When displaying DF, individuals are highly vulnerable and effectively bet on the attitude of the predator; this risky choice is presumably under positive selection. We explored how propensity for DF varies among and within populations of dice snakes (Natrix tessellata). We also considered the influence of sex, body size, reproductive status, colour morph and presence of injuries (N = 2760 snakes; five populations). DF propensity differed among populations, possibly due to variation in local predation pressures. Larger snakes displayed DF more frequently and carried more signs of probable past predation attempts (scars and recent injuries). We found no sex effect on antipredator behaviour. Gravid females used DF less frequently compared with non‐gravid females. Differential expression of DF across populations, body sizes and reproductive status suggests that this complex behaviour was selected to respond to environmental and intrinsic factors. Future studies should explore which elements affect duration, intensity and success of DF in defence against various predators. [ABSTRACT FROM AUTHOR]

Body condition in mammals fluctuates depending on energy intake and expenditure. For brown bears (Ursus arctos), high‐protein foods facilitate efficient mass gain, while lipids and carbohydrates play important roles in adjusting dietary protein content to optimal levels to maximize energy intake. On the Shiretoko Peninsula, Hokkaido, Japan, brown bears have seasonal access to high‐lipid pine nuts and high‐protein salmon. To assess seasonal and annual fluctuation in the body condition of adult female brown bears in relation to diet and reproductive status, we conducted a longitudinal study in a special wildlife protection area on the Shiretoko Peninsula during 2012–2018. First, analyses of 2,079 bear scats revealed that pine nuts accounted for 39.8% of energy intake in August and salmon accounted for 46.1% in September and that their consumption by bears varied annually. Second, we calculated the ratio of torso height to torso length as an index of body condition from 1,226 photographs of 12 adult females. Results indicated that body condition continued to decline until late August and started to increase in September when salmon consumption increased. In addition, body condition began to recover earlier in years when consumption of both pine nuts and salmon was high. Furthermore, females with offspring had poorer body condition than solitary females, in particular in late August in years with low salmon consumption. Our findings suggest that coastal and subalpine foods, which are unique to the Shiretoko Peninsula, determine the summer body condition of female brown bears, as well as their survival and reproductive success. [ABSTRACT FROM AUTHOR]

According to ecological theory, two species cannot occupy the same niche. Using nitrogen isotope analyses (δ15N) of amino acids, we tested the extent to which two sympatric deposit‐feeding amphipods, Monoporeia affinis and Pontoporeia femorata, partition their trophic resources. We found that trophic position (TP) and resynthesis index (∑V; a proxy for degradation status of ingested material prior to assimilation by the consumer) differ between species. The surface‐feeding M. affinis had higher TP and intermediate ∑V, both pointing to a large contribution of metazoans in its diet. P. femorata, which feeds in the subsurface layers, had lower TP and a bimodal distribution of the ∑V values, supporting previous experimental evidence of a larger feeding niche. We also evaluated whether TP and ∑V values have consequences for amphipod fecundity and embryo viability and found that embryo viability in M. affinis was negatively linked to TP. Our results indicate that the amino acid‐δ15N data paired with information about reproductive status are useful for detecting differences in the trophic ecology of sympatric amphipods. [ABSTRACT FROM AUTHOR]

Abstract: An improved understanding of the biology of the invasive pest, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), is critical for the development of effective management strategies. Trapping is one technique used for both detection and control; however, the efficacy of trapping can vary depending on the target insect's physiological state, its behavioural priorities and the type of attractant used in the trap. We conducted a series of caged trapping experiments and a greenhouse trapping experiment to investigate the effects of D. suzukii feeding status, age, mating status, ovipositional status and seasonal morph type on the capture rate of traps baited with fermentation odours. Starved flies were trapped at greater rates compared to fed flies; more virgin flies were trapped than mated flies; flies deprived of an oviposition substrate were trapped more frequently than flies given an oviposition substrate. It is still unclear whether age or seasonal morphology affect bait response. Lastly, a caged choice experiment investigated the relationship between female reproductive status and attraction to fermentation or fruit odours. Fermentation‐based traps captured female flies regardless of their reproductive status but, ripe fruit‐based traps were more attractive to flies with more than seven eggs. In summary, studies that use fermentation‐based traps should recognize that capture rates of D. suzukii will depend on the feeding, mating and oviposition experiences of the population; also, fruit‐based traps may better target gravid females. [ABSTRACT FROM AUTHOR]

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Questions Ant-gardens ( AGs) involve a close association between epiphytes and ants with concurrent mutualistic interactions including protection, dispersal and nutrition; however, little is known about the spatial structure patterns that determine their establishment and formation. Our main questions were: (1) do AGs have a particular pattern of vertical distribution on their host trees; (2) does a process of succession of epiphytes occur during development of AGs; and (3) are epiphytes segregated in AGs? Location Anthropic landscape in southeast Mexico. Methods We studied AGs built by Azteca gnava ants. We examined their vertical distribution on host trees as well as the diversity, composition and reproductive status of vascular epiphytes associated with the lower, middle and upper zones of small, medium and large AGs. Results A total of 859 AGs and 10 871 epiphytes, belonging to 26 different species, were recorded. We found that AGs are primarily (75%) located within tree crowns, and that the diversity and composition of epiphytes vary among AG sizes and among AG zones. We infer that the epiphytes that first become established in AGs are the bromeliad Aechmea tillandsioides and the gesneriad Codonanthe uleana, followed by the orchid Epidendrum flexuosum and the cactus Epiphyllum phyllanthus; these species were recorded, either individually or in co-occurrence, in 74% of the AGs examined. The species Ae. tillandsioides, Coryanthes picturata and Epid. flexuosum were most frequent in the upper AG zone, while Epid. pachyrachis was most frequent in the middle AG zone. Conclusions Our results show that AGs have distinct vertical distribution patterns on their tree hosts and that the establishment of epiphytes in AGs is successive and segregated, suggesting spatial and temporal optimization in the establishment and development of these complex mutualistic systems. [ABSTRACT FROM AUTHOR]

Contests between males fighting over limited resources often determine the reproductive success of the contestants. It is possible that the outcomes of such contests are affected by traits that also contribute to the likelihood of males achieving paternity when sperm from multiple males compete to fertilize the ova of a single female; however, this relationship has been poorly characterized. In dung and carrion roller beetles, contests among males for the possession of a food ball - a vital resource for nesting - are frequent in nature. However, females that roll and nest with a male often store the sperm of previous mates, forcing males to engage in sperm competition. We analyzed the relationship between wins and losses in contests between food ball owner males and subsequent paternity success in the carrion roller beetle Canthon cyanellus using both naïve (virgin) and experienced (previously mated) males. Owner males that initiated contests were more likely to win, and contest durations were longer between experienced owner males than between naïve owners. The paternity of the winner owner males nesting with a female that had previously mated with another male was higher than for loser owner males, and the paternity of experienced owners also tended to be higher than for virgin owners. Our results indicate that winning and being an experienced male are associated with greater success at fighting and sperm competition than losing and being a naïve male. [ABSTRACT FROM AUTHOR]

Life history parameters were determined for stranded and bycaught harbor porpoises ( Phocoena phocoena) from Scottish ( UK) waters (1992-2005). Fetal growth rate was 84.4 mm/mo and mean size at birth was 76.4 cm (range 65-88 cm). Males and females had a similar range of body lengths (65-170 cm and 66-173 cm, respectively), although asymptotic lengths were higher in females than males (approximately 158 cm and 147 cm, respectively). Nonpregnant females were significantly lighter, in relation to their length than males. Maximum estimated age was 20 yr for both sexes. Age at sexual maturity ( ASM) was estimated as 4.35 yr in females and 5.00 yr in males. Conception occurred mainly in July and August although reproductively active males were recorded during April to July. Gestation lasted 10-11 mo, with calving mainly between May and July. Lactating females were recorded during June to November, while small calves with solid food in their stomachs were found mainly during February to May. Estimated pregnancy rate (0.34-0.40) is lower than recorded elsewhere, but is likely underestimated due to the prevalence of mature females of poor health status in the sample. Nevertheless, cetacean strandings can be an essential source of data on demographic parameters. [ABSTRACT FROM AUTHOR]

This article discusses the exposure of hornyhead turbot fish to estrogenic endocrine disrupting compounds in the wastewater effluent off Orange County California. The authors measured seasonal changes in developmental stages, condition factor (CF), plasma vitellogenin (Vtg) concentrations and gonadosomatic index, in male and female fish. They found that fish collected from the sites exhibited male-oriented sex ratios, but indexes were not significantly different in samples collected from different sites at the same sampling period. They concluded that the histopathological and reproductive responses appeared to be insignificant and may not affect the population in these locations.

Studies of space use and habitat selection of endangered species are useful for identifying factors that influence fitness of individuals and viability of populations. However, there is a lack of published information regarding these behaviors tot the federally threatened Louisiana black bear (Ursus americanus luteolus). We documented space use and habitat selection for 28 female black bears in 2 subpopulations of the Tensas River Basin population in northeast Louisiana, USA. The Tensas subpopulation inhabits a relatively large (>300-km²) contiguous area of bottomland hardwood forest, whereas the Deltic subpopulation exists mainly in 2 small (<7-km²) forested patches surrounded by an agricultural matrix. Females on Deltic maintained smaller seasonal and annual home ranges than |~males on Tensas (all P < 0.04), except for females with cubs during spring. On Tensas, females with cubs maintained smaller home ranges than females without cubs during spring (P < 0.01), but we did not detect this difference on Deltic or in other seasons. Females on Tensas and Deltic exhibited differences in habitat election when establishing home ranges and within home ranges (P < 0.0001). Deltic females selected mature bottomland hardwood forests and avoided agricultural habitats at both spatial scales. Tensas females selected a mixture of swamps, mature and regenerating forests, and exhibited variation in selection across scale, season, and reproductive status. We suggest that differences in space use and habitat selection between Tensas and Deltic are at least partially due to habitat differences at the landscape (i.e., amount of forested habitat) and patch (i.e., food availability) scales. Our results contribute to the understanding of factors that influence space use and habitat selection by black bears and provide specific information on habitat types selected by Louisiana black bears to agencies involved in habitat protection and restoration fix this threatened subspecies. [ABSTRACT FROM AUTHOR]

This study aimed to test how the sex and reproductive status of Eurasian lynx influenced their use of ‘attractive sinks’– habitats with high prey density and high mortality risks. Locations of 24 Eurasian lynx Lynx lynx were obtained by radio-telemetry in a mixed forest and agricultural habitat in south-eastern Norway. Roe deer, the major food source of lynx in the study area, occurred at higher densities closer to areas of human activity and infrastructure. Proximity of lynx locations to human activity and infrastructure was used as a risk index because the most common causes of death among Scandinavian lynx were of anthropogenic origin. This study shows that distances from lynx locations to human activity were significantly greater for females with newborn kittens than for males, but this decreased with kitten age. The data suggest that this response to human activity is influenced by the reproductive strategies of males and females, and might explain male-biased human-induced mortality in this study and in carnivores more generally. [ABSTRACT FROM AUTHOR]

Current understanding of the extent, causes for, and consequences of variation in nutrient composition in plants is limited. Important questions to be addressed include to what extent nutrients covary, how flexible nutrient ratios are within a population or species, how reproduction influences nutrient ratios, and how much the ratios of nutrients to mass and nutrients to each other change through ontogeny. This information is needed to assess the physiological and ecological consequences of plant nutrient composition and to what extent plants function as balanced systems in acquisition and allocation of resources. We studied the variation in nutrient stoichiometry (i.e., the ratio between contents of different nutrients within a plant) in relation to three factors: (1) environmental availability of nitrogen, (2) plant size, and (3) reproductive status. We investigated these questions in 11 populations of the carnivorous plant Pinguicula vulgaris in northern Scandinavia. Dry mass and N and P content were measured for reproductive and vegetative portions of flowering individuals and for winter buds corresponding to four reproductive states: control reproductive individuals, experimentally vegetative individuals (from which flower buds were removed), adult vegetative individuals, and individuals below the threshold size for reproduction. [N], [P], and to a lesser extent, N and P content were positively related to soil N, but not to prey capture. Nutrient stoichiometry was also size dependent; in general, small plants were relatively enriched in N and relatively depleted in P compared to larger plants. Reproductive status affected not only size, but also nutrient stoichiometry of the resulting winter bud. Winter buds derived from reproductive individuals had a higher [N] and lower [P] than those of the different types of nonreproductive individuals. Our findings indicate that studies of nutrient stoichiometry in plants must go beyond links between environmental and plant nutrient concentrations to consider internal processes such as growth and reproduction. [ABSTRACT FROM AUTHOR]

Summary 1. Data on seasonal ranges of 93 radio-collared adult brown bears (Ursus arctos ) were used to test hypotheses explaining variation in range size in relation to male and female reproductive strategies. 2. Both males and oestrous females used large ranges in the mating season, but decreased their ranges after the mating season. These results suggested that both sexes in this species roam to mate, because the results could not be explained by a seasonal change in food availability nor by increased foraging movements of oestrous females to replenish body reserves after previous cub raising. 3. Females with cubs-of-the-year (cubs) restricted their range size in the mating season and increased their ranges in the post-mating season. This finding suggests that females with cubs restricted their ranges to avoid contact with infanticidal males, an important cause of cub mortality, because the proposed alternative explanation - limited mobility of small cubs - was unable to explain the small size of mating season ranges. 4. Our results suggest that range size in females is influenced by sexually selected infanticide, selecting for large mating season ranges and multiple mating in oestrous females to hide paternity and for restricted mating season ranges in females with cubs to avoid infanticidal males. 5. To our knowledge, we are the first to report a significant relationship between seasonal range size and reproductive status in female brown bears and the first to report an effect of oestrus on seasonal range size in female carnivores. [ABSTRACT FROM AUTHOR]

Adult populations of Hyalella azteca, with similar reproductive potential, were exposed in the laboratory to a range of lindane concentrations below the 240-h adult LC50 (26.9 mu g/L) for a period of 35 d. The reproductive status of each population was assessed through quantification of the precopulatory guarding behavior of Hyalella, the number of gravid females, and their brood size. At the end of the experiment, recruitment within the H. azteca populations was assessed, and the body lengths of individuals were measured using image analysis. By employing a range of integrated and quantifiable response criteria,the influence of lindane at the individual and at the population level was determined. A lowest observed effect concentration of 13.5 mu g lindane/L was identified. The experimental results are discussed inrelation to the reproductive strategies adopted within the treatmentgroups and with respect to previous toxicity data. [ABSTRACT FROM AUTHOR]

The present report documents the breeding success of a new colony of common marmosets (Callithrix jacchus jacchus) and demonstrates a correlation between environmental stress and reproductive success. Environmental conditions ranged chronologically over 40 months, through four periods: I) the initial period, when the colony was formed; II) a phase of relative environmental stability; III) a stage of "environmental stress" (when the colony was disrupted by nearby construction); and IV) a return to a stable environment. Examination of reproductive status during each period indicated that the colony exhibited severe reproductive suppression during the time of the environmental disruption. Parity and the number of live births decreased and the number of spontaneous abortions increased during this period. Reproductive success remained low during period IV. More triplets than twins were born during the period of relative environmental stability., (Copyright © 1991 Wiley‐Liss, Inc., A Wiley Company.)