Overwintering Sites Research Articles

Как быстро снижается численность популяции степного орла? Результаты наблюдений в Эйлате, Израиль

The world Steppe Eagle ( Aquila nipalensis ) population is considered Endangered and is rapidly declining across most of it range. Eilat, in southernIsrael, is a bottleneck for this species on its migration route fromAfrica in spring. We conducted a series of surveys, counting the passing Steppe Eagles in springs 2015 to 2018 and collecting data about the age of the passing birds. We then compared our data with the Steppe Eagle data collected during four springs between 1977 and 1988. We did not find a significant decline in Steppe Eagle numbers passing Eilat on their spring migration between the two data sets. This implies that the overwintering sites in Africa and the migration flyway to and fromAfrica are relatively safe for the Steppe Eagles. We furthermore found that 75% of the eagles passing are adults and that their main passage is during the third week of February. This information helps to adjust conservation efforts.

Spatial ecology and multi-scale habitat selection by Western Painted Turtles (<i>Chrysemys picta bellii</i>) in an urban area

As urban centres expand, knowledge on the habitat and space use of native wildlife, particularly long-lived species, is required for proper management. Our objective was to understand space requirements and key habitat features necessary for long-term persistence of Western Painted Turtles (Chrysemys picta bellii) living in a Canadian urban park. Using radio telemetry, we examined seasonal habitat selection and space use over two years, 2015–2016 (n = 23), and 2016–2017 (n = 29) in Regina, Saskatchewan. Daily movements and home ranges of males and females were smaller during emergence than during nesting or post-nesting phases of the active season. Turtles inhabiting marsh sites had 2- and 4-times larger daily movements and home ranges compared to turtles inhabiting the creek. Turtles selected the shoreline habitat over urban/parkland and open water. Turtles used marsh-shoreline habitats non-randomly, selecting accessible shoreline with large trees in the active season. In contrast, turtles used creek-shoreline habitat according to availability. Overwintering sites selected by turtles were warmer and deeper than random available sites, with no difference in dissolved oxygen level. However, water was hypoxic for most overwintering sites. Our results show that turtles range widely, requiring 20–60 ha throughout the year. Urban park areas should be managed to provide accessible shorelines with a combination of cover and open basking areas. Critically, careful attention needs to be paid to managing water depth so that over-wintering sites remain viable.

Leukocyte profiles vary with breeding latitude and infection status in a seasonally sympatric songbird

Abstract Billions of animals migrate annually in pursuit of food, safety, and reproduction. Long-distance migration can be energetically expensive, which can force tradeoffs with investment in other physiological systems (e.g., suppressing immunity). Understanding the physiological impacts of migration is important to predict when and where such animals may be vulnerable to parasites and how changes to migration might affect infectious disease risks. To isolate relationships between migration and physiology from energetic tradeoffs and hormonal shifts associated with spring reproduction, we assessed differences in leukocyte profiles between seasonally sympatric resident and recently arrived fall migrant dark-eyed juncos (Junco hyemalis) in the Appalachian Mountains. When examining heterophil:lymphocyte (HL) ratios, which can elevate for long durations after even mild stressors, we found weak associations with migratory strategy (resident or migrant subspecies). In contrast, feather δ2H values showed that HL ratios were highest for juncos breeding at more northern latitudes, and this relationship was strongest for birds that arrived at the overwintering site infected with haemosporidian parasites (Plasmodium and Haemoproteus spp.). These patterns were more pronounced and better indicated hematological responses to stressors when using multivariate analyses. Our findings suggest that short- and long-distance migration may be more energetically costly in the presence of infection and highlight how approximating breeding latitude and using multivariate analyses can help understand host physiology.

Phylogenetic variations of highly pathogenic H5N6 avian influenza viruses isolated from wild birds in the Izumi plain, Japan, during the 2016-17 winter season.

During the 2016-2017 winter season, we isolated 33 highly pathogenic avian influenza viruses (HPAIVs) of H5N6 subtype and three low pathogenic avian influenza viruses (LPAIVs) from debilitated or dead wild birds, duck faeces, and environmental water samples collected in the Izumi plain, an overwintering site for migratory birds in Japan. Genetic analyses of the H5N6 HPAIV isolates revealed previously unreported phylogenetic variations in the PB2, PB1, PA, and NS gene segments and allowed us to propose two novel genotypes for the contemporary H5N6 HPAIVs. In addition, analysis of the four gene segments identified close phylogenetic relationships between our three LPAIV isolates and the contemporary H5N6 HPAIV isolates. Our results implied the co-circulation and co-evolution of HPAIVs and LPAIVs within the same wild bird populations, thereby highlighting the importance of avian influenza surveillance targeting not only for HPAIVs but also for LPAIVs.

Presence of the invasive brown marmorated stink bug Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) on home exteriors during the autumn dispersal period: Results generated by citizen scientists

AbstractThe invasive brown marmorated stink bug Halyomorpha halys (Stål) is a serious nuisance pest in buildings. To address how H. halys select potential overwintering sites and to predict the risk of home invasion, citizen scientists, primarily from the Mid‐Atlantic region of the U.S.A., were recruited to count the number of H. halys present on the exterior of their homes during the autumn dispersal periods in 2013 and 2014. Volunteers provided daily count data on numbers present on each exterior aspect of the home during the peak dispersal, as well as their home's location, colour and structural material. Among volunteers, fewer adults were counted on white homes compared with brown and tan homes in 2013 and with grey homes in both years. Across all homes, greatest numbers were counted on the north and east walls in both years and on homes with wood, cement or stone exteriors. In addition, significantly more adults were counted on homes in rural landscapes compared with urban areas in both years. Halyomorpha halys were found in greater numbers on darker coloured homes made of natural materials, even though these were less common than other types in the landscape. Thus, homes located in rural landscapes with these features could be prone to larger nuisance infestations of overwintering H. halys.

Wood addition in the hatchery and river environments affects post‐release performance of overwintering brown trout

Abstract Habitat structural complexity affects the behaviour and physiology of individuals, and responses to the environment can be immediate or influence performance later in life through delayed effects. Here, we investigated how structural enrichment, both pre‐release in the hatchery rearing environment and post‐release in the wild, influenced winter growth and site fidelity of brown trout stocked into side channels of a regulated river. Experiencing structural enrichment in the rearing environment during 3 months in autumn had no pre‐release effect on growth, but a delayed positive effect after release during the subsequent winter. Moreover, trout recaptured in wood‐treated sections of the side channels had grown more than trout recaptured in control sections. Wood enrichment in the side channels also increased overwinter site fidelity. These results show that adding structure during a relatively short period may alter growth trajectories, and adding wood to side channels is a cost‐effective method to enhance winter habitat carrying capacity for juvenile salmonids in regulated rivers.

Landscape structure alters the abundance and species composition of early-season aphid populations in wheat fields

Agricultural landscape composition is reported to have effects on the occurrence of natural enemies in fields, but the responses of herbivorous pests to landscape features have rarely been studied. Our previous landscape-level study in northern China found that natural enemies had no significant effects on the population growth of wheat aphids at the colonization stage. Hence, we hypothesised that the initial aphid population in wheat fields may largely depend on immigration events from other habitats. In this study, we investigated the effects of landscape pattern on wheat aphid abundance and species composition at the colonization stage by surveying population densities of different aphid species along a landscape gradient. We found that noncrop habitats such as woodlots, fallow lands and vegetation around dwellings or wetlands in the landscape all had positive correlations with aphid abundance in wheat fields because they provided a source for aphid colonization. More specifically, the proportion of woodlots, fallow lands, dwellings, and other crops increased the abundance of Rhopalosiphum padi (L.), and the existence of water and dwellings in an agricultural landscape facilitated the occurrence of Sitobion avenae (Fabricius). Likewise, the abundance of Schizaphis graminum (Rondani) in wheat fields was found to be significantly promoted by the presence of water. The habitats around water and dwellings usually provide the overwintering sites for the aphids. Furthermore, wheat production acreage had a significant negative correlation with the abundance of R. padi, S. avenae and S. graminum. Landscape characteristics had a significant effect on the species composition of wheat aphids. Our study suggests that noncrop habitats in a landscape enhance aphid occurrence at the population colonization stage, and differences in overwintering host plants among aphid species may be responsible for the differing responses of the abundance of different aphids to landscape variables, which greatly altered aphid population composition across different landscapes. These results highlight the need for taking landscape effects on the pest itself into consideration when designing landscape-level pest management strategies.

Habitat preference of Drosophila suzukii across heterogeneous landscapes

In temperate regions, generalist insect pests are expected to use multiple habitats and host plant species over the different seasons. Landscape composition and configuration can also provide a diversity of thermal resources and host plants that can modify insect activity and movement. Here, we described the seasonal spatial distribution of a destructive invasive pest, spotted wing drosophila (SWD), along a gradient of landscape composition (i.e. proportion of forest habitat) and configuration (i.e. length of forest edge). We selected a triplet of habitat patches (forest, vineyard and grassland) in 17 landscapes in North-eastern Italy characterised by different proportions of forest and forest edge length and monitored pest activity density for 1 year. We found that during the cold season, SWD mostly occupied forest habitats, which were suitable overwintering sites due to ideal microclimatic conditions. During plant-growing season, SWD occurred equally in the three habitats, probably due to warmer temperatures in open areas as well as high food and host availability. In summer, when high temperatures can be limiting, landscapes with large forest edge length presented an increase in activity density compared to landscapes with less amount of edges, irrespective of the total cover of forest. Large edge length indicated landscapes with high contact zones between forest and open habitats, probably favouring spillover of individuals in SWD. In the light of these results, pest control in crop fields located in landscapes with complex configurations can be particularly challenging. The high density in non-crop habitats suggests that this invasive species can have pervasive impact also on wild plant species occurring in semi-natural and natural habitats.

Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) overwintering: an overview

AbstractThe Dacini fruit flies are tropical and subtropical insects for which a winter diapause is largely unknown. However, some pest dacines have extended their geographic ranges into temperate areas where winter temperatures may be limiting. During the 1900s, Bactrocera tryoni (Froggatt) extended its Australian endemic tropical range to include temperate southern Australia. Starting nearly 100 years ago, several research teams have spent considerable effort understanding how ‘tropical’ B. tryoni survives temperate winters: this review summarises that research. Across three study areas (Sydney and surrounding districts, New South Wales; Melbourne and surrounding districts, Victoria; Stanthorpe, south‐eastern Queensland), there is highly consistent data showing that the fly overwinters almost exclusively in the adult form. Eggs, larvae and pupae generated in late autumn or early winter either fail to develop due to lack of sufficient day‐degree accumulation or if immature development is successful and adults emerge, then those adults do not become sexually mature until the spring. Females which are already sexually mature when entering winter resorb some or all of their eggs. During winter, adults rest in sheltered locations and will forage for food on warm days. In field cages, mortality of adults is approximately 8% per week during winter, and so significant adult mortality occurs during winter. Based on laboratory studies, adult survival at cool to cold (15°C to −4°C) temperatures is increased if the fly or earlier developmental stages (pre‐pupal maggots and fully developed pupae) undergo an acclimation process, rather than being subjected to a sudden drop in temperature. Early climate change modelling suggests that a decrease in the number of extreme cold events (i.e. hard frosts) is more likely to lead to improved fly survival in temperate areas than the overall mean temperature increase. Gaps in knowledge include quantification of what makes a preferred overwintering site; how climate change over the last 30 years (when the last detailed experiments were done) have modified overwintering phenologies; and where on the Australian east coast does temperature become limiting such that year‐round breeding ceases.

Both woody and herbaceous semi-natural habitats are essential for spider overwintering in European farmland

Semi-natural habitats (SNH) support biodiversity and associated ecosystem services on farmland, thereby contributing to sustainable agriculture. However, little is known about the specific suitability of different types of SNH as overwintering habitat for predatory arthropods, despite the crucial role of such knowledge for conservation biological control. We used ground photoeclectors to sample spiders in 65 habitats comprising crop fields and four major SNH types (herbaceous areal, herbaceous linear, woody areal, woody linear) across two study regions in Switzerland and Germany to identify the most important overwintering habitats for spiders. Spider emergence started in February and over half of the individuals of the most common spiders had already emerged by late April. SNH supported on average 146% higher species richness and 194% higher densities of spiders than crop fields. Woody and herbaceous SNH supported distinct spider communities, with individual species exhibiting marked preferences for either woody or herbaceous SNH. Habitat shape (areal or linear) had no significant effects on spider overwintering. Woody SNH hosted more species, whereas herbaceous SNH had higher densities of agrobiont species (i.e. species known to reach high densities in crops in the growing season). Given the higher number of overwintering agrobionts in herbaceous SNH, this habitat type has potential to promote pest control by spill-over of spiders into nearby crops early in the season. In contrast, woody SNH seem to be more important for the conservation of diverse spider communities that are highly distinct from those inhabiting open land. Hence, creating and preserving a variety of SNH is key to provide suitable overwintering sites for species in agricultural landscapes.

A long-term survey of spring monarch butterflies in north-central Florida

Long-term springtime counts of immature and adult monarch butterflies and their Asclepias humistrata host plants in north-central Florida reveal a close relationship between the milkweed’s phenology and the butterfly’s spring remigration from Mexico. Remigrant adults arrive after most frosts occur and as the milkweeds are flourishing but before the plants begin to senesce. The peak of adult arrival is during the first few days in April; the eggs that are laid during this peak develop through April, leading to a second peak in adult abundance in early May. These newly emerged adults continue the migration northward. In addition to assessing the phenology of annual events, our long-term survey, with regular monitoring from 1994–2017, has enabled us to evaluate long-term trends. Both adults and immatures have declined in abundance from 1985 to 2017; since 2005, both have declined by around 80%. This decline has occurred concurrently with the decline in the number of monarchs at their Mexican overwintering sites.

Seasonal movements of striped bass Morone saxatilis in a large tidal and hydropower regulated river

Following a failed spawning event in 1975 and the suspected absence of recent spawning by Striped Bass Morone saxatilis in the Saint John River, New Brunswick, the native Striped Bass population has been considered extirpated. Non-native migratory Striped Bass, however, still frequent the river, and a remnant, likely native, population may still exist. To characterize the movements and habitat use of adult Striped Bass still arriving to, and possibly residing within the Saint John River, Striped Bass (n = 40, size range, 40.5–90.9 cm FL) were captured throughout 2010–13 in the lower Saint John River, and surgically implanted with multi-year acoustic transmitters. Striped Bass were passively tracked using an array of 5–33 project specific receivers between 2010 and 14 and augmented by detections from the Ocean Tracking Network from 2011 to 13. Most tag detections recorded during the predicted spawning period occurred near locations suspected to have supported Striped Bass spawning historically. Only six tagged fish (15% of total) were detected outside of the river, five of which only left the river briefly during the spawning period and then returned. Tagged Striped Bass used four overwintering sites within the Saint John River to which individuals demonstrated annual fidelity. Our findings suggest the presence of a local, possibly reproducing Striped Bass population that exhibits multi-annual residency within the river; however, successful spawning remains to be confirmed.

Fire Management in a Natural Protected Area: What Do Key Local Actors Say?

Public policies on fire in forest ecosystems are changing from fire-fighting and suppression to an integrated management approach that incorporates ecological and social considerations. However, policy implementation is usually directed by central governments without considering local actors. We identified key local actors in the Monarch Butterfly Biosphere Reserve, Mexico. This is an important natural protected area of high socio-environmental complexity and the overwintering sites of monarch butterfly that migrate from Canada and United States every year. We applied network and grounded theories to analyze qualitative information derived from semi-structured interviews with 28 key local actors including government employees, local inhabitants, non-governmental organization and academic personnel. We identified actors who play essential roles in local fire management. Aside from fire-fighting, local actors engage in fire prevention, habitat restoration, research, training, planning, coordination, and communication activities that are specific to a spatial, temporal, institutional, and environmental context of fire management. The incorporation of the concepts that local actors associate with fire knowledge, behavior, and regimes would result in better planning for fire management in the short, medium, and long-term.

Spatio-Temporal Analysis of Wetland Changes Using a Kernel Extreme Learning Machine Approach

Natural wetland ecosystems provide not only important habitats for many wildlife species, but also food for migratory and resident animals. In Shanghai, the Chongming Dongtan International Wetland, located at the mouth of the Yangtze River, plays an important role in maintaining both ecosystem health and ecological security of the island. Meanwhile it provides an especially important stopover and overwintering site for migratory birds, being located in the middle of the East Asian-Australasian Flyway. However, with the increase in development intensity and human activities, this wetland suffers from increasing environmental pressure. On the other hand, biological succession in the mudflat wetland makes Chongming Dongtan a rapidly developing and rare ecosystem in the world. Therefore, studying the wetland spatio-temporal change is an important precondition for analyzing the relationship between wetland evolution processes and human activities. This paper presents a novel method for analyzing land-use/cover changes (LUCC) on Chongming Dongtan wetland using multispectral satellite images. Our method mainly takes advantages of a machine learning algorithm, named the Kernel Extreme Learning Machine (K-ELM), which is applied to distinguish between different objects and extract their information from images. In the K-ELM, the kernel trick makes it more stable and accurate. The comparison between K-ELM and three other conventional classification methods indicates that the proposed K-ELM has the highest overall accuracy, especially for distinguishing between Spartina alternflora, Scirpus mariqueter, and Phragmites australis. Meanwhile, its efficiency is remarkable as well. Then a total of eight Landsat TM series images acquired from 1986 to 2013 were used for the LUCC analysis with K-ELM. According to the classification result, the change detection and spatio-temporal quantitative analysis were performed. The specific analysis of different objects are significant for learning about the historical changes to Chongming Dongtan and obtaining the evaluation rules. Generally, the rapid speed of Chongming Dongtan’s urbanization brought about great influence with respect to natural resources and the environment. Integrating the results into the ecological analysis and ecological regional planning of Dongtan could provide a reliable scientific basis for rational planning, development, and the ecological balance and regional sustainability of the wetland area.

Small-scale agricultural landscapes promote spider and ground beetle densities by offering suitable overwintering sites

Intensive agricultural management practices and landscape homogenisation are the main drivers of biodiversity loss in agricultural landscapes. Agricultural fields are regularly disturbed and provide unstable habitats due to crop management regimes. This may lead to movement of arthropods into neighbouring non-arable habitats, as natural and semi-natural habitats provide suitable overwintering sites. Here we assessed the effect of landscape composition and configuration on the overwintering spider and carabid fauna of grassy field margins and hedgerows. We sampled ground-dwelling arthropods at field edges of different types (grassy field margin and hedgerows), landscape composition (diverse and simple) and configuration (mosaic and large-scale agricultural landscapes). We detected larger spiders in hedgerows than in grassy field margins and in complex landscapes rather than in simple landscapes. We found a significant effect of interaction between landscape composition and edge type on ballooning propensity of spiders. Agrobiont carabids were more abundant in field edges of compositionally simple and large-scale agricultural landscapes. Furthermore, we showed an effect of interaction between landscape composition and edge type on agrobiont spiders. We collected larger carabids in grassy field margins than in hedgerows and carabids were smaller in simple landscapes than in diverse landscapes. The spider community was affected by edge type, and landscape composition had a significant effect on the carabid community. Small-scale agricultural landscapes may have higher overall densities of ground-dwelling spiders and carabids than large scale landscapes due to the relatively high edge density and the higher quantity of available overwintering sites.

Enhancing predator efficiency, the recent advances

Three biocontrol methods include classical biological control, augmentation and conservation (CBC). Among them, CBC includes different agricultural compatible methods, which try to build up natural enemy populations and consequently improve biological control. Some of the most common conservation methods include providing shelter (e.g. beetle banks and hedgerows), supplementary foods (pollen and nectar), providing overwintering sites, increasing landscape biodiversity and nesting. Furthermore, cover crops, living mulches, which buffer the harsh environmental conditions, strip harvesting are among the other most common methods. Recently, genetic manipulation of predators has been considered as a potential strategy in biological control. This strategy aimed to manipulate beneficial genetically to more tolerant them against adverse effect of pesticides and environmental condition or increase their predation (parasitism rate). We tried to review a growing body of conservation studies focusing on practices promoting predator efficacy and performance. We will discuss how CBC practices contribute to improve pest control.

Where have all the monarchs gone?

Ecology North American monarch butterfly populations have declined at their Mexican overwintering sites in recent years. The picture is less clear for monarch summer breeding sites in the United States and Canada. In a Perspective, Agrawal and Inamine report on recent survey results and conclude

Ecology of neonate eastern box turtles with prescribed fire implications

ABSTRACTLittle is known about the movements and behavior of neonate eastern box turtles (Terrapene carolina carolina). We investigated spatial ecology of neonate eastern box turtles at 4 upland openings in the Manistee National Forest, Michigan, USA, 2012–2016. We protected nests and used radio‐telemetry to document dispersal from nests, land cover types used for overwintering, and residency time of neonates in natal openings. We used binomial logistic regression to model probabilities of overwintering in natal openings versus adjacent forest and edge. We protected 64 nests, radio‐fitted 64 neonates over 4 cohort years, tracked 46 neonates from nest emergence to their overwintering sites, and tracked 28 neonates for portions of their second activity season. Dispersal (straight‐line distance from nest to overwintering site) was limited in the first activity season (n = 46 neonates, = 19.9 ± 2.4 m [SE], range = 1.9–83.2 m) and 24 overwintered in natal openings, 4 overwintered in the forest edge, and 18 overwintered in forest. Our best logistic model included the predictor variables distance from nest to nearest forest edge and day of nest emergence. Probability of overwintering within a natal opening was greater for neonates from nests located farther from the forest edge and for neonates emerging from nests later in the year. By 1 June of their second activity season, all tracked turtles were still present in, or within 50 m, of their natal opening, but all neonates had dispersed into surrounding forest or wetlands by 1 July. Managers should be aware that neonates reside in or very near their natal openings for several months after nest emergence. When burning or otherwise intensively managing open canopy box turtle nesting areas, relaxing the interval (yr) between treatments and excluding forest edge and adjacent forest should allow neonates time to disperse, decreasing risk of mortality. © 2018 The Wildlife Society.

Citizen Scientist Tagging Reveals Destinations of Migrating Monarch Butterflies,Danaus plexippus(L.) from the Pacific Northwest

The fall migration of Monarch butterflies (Danaus plexippus) in the Pacific Northwest (PNW) was studied in an unfunded citizen science project during 2012—16 by tagging 13778 reared and 875 wild Monarchs. More than a third of these Monarchs were reared by inmates of the Washington State Penitentiary (WSP) in Walla Walla, Washington. Sixty (0.41 %) tagged Monarchs were recovered from distances greater than 10 km (mean: 792.9 ± 48.0 km) with most found in California, SSW of release points. One WSP-reared Monarch was found 724 km to the SE in Utah. Monarchs tagged in Oregon flew SSE to California. No Idaho-tagged Monarchs were found in California but two were recovered at locations due south. No wild tagged Monarchs from Washington, Oregon or Idaho were recovered. Monarchs from Washington and Oregon were found during October-February at 24 coastal California overwintering sites spanning 515 km from Bolinas to Carpinteria. A single wild spring Monarch tagged in May in northern California was recovered 35 days later and 707 km ENE in Twin Falls, Idaho. This study provides compelling evidence that many Monarchs in southern and central parts of Washington and Oregon migrate south in the fall to overwintering sites along the California coast. It also provides some evidence for southerly and south-easterly vectoring of migrating Monarchs from eastern Washington and Idaho, indicating the possibility of migration to Arizona or Mexico overwintering sites. In addition to improving our understanding of Monarch migration in the PNW, this study also contributed to conservation by adding nearly 14000 butterflies to the population. The incredible involvement of incarcerated and non-incarcerated citizen scientists generated much community and media interest which in turn led to greater involvement by citizens. Increased awareness of Monarchs, their biology and conservation in the PNW has been an unexpected but important spin-off of this study.

Effects of food quality on Melolontha spp. adults

Abstract The paper presets the results of the study on the life span, survival, body weight and fecundity of cockchafer (Melolontha spp.) adults feeding on the leaves of Betula pendula Roth., Quercus robur L., Q. rubra L., Acer platanoides L., Tilia cordata Mill. and Pinus silvestris L. inflorescences. The life span and body weight of adults, as well as female fertility were examined in the years 2015, 2016 and 2017. In 2015, the tested common cockchafer (Melolontha melolontha L.) adults and forest cockchafer (Melololntha hippocastani F.) adults were fed on B. pendula., Q. robur and P. silvestris. In 2016, forest cockchafer adults were fed on B. pendula, Q. robur, Q. rubra, T. cordata, and in 2017 – on B. pendula., Q. robur T. cordata and A. platanoides. Adults of both species feeding on Q. robur were treated as the control. Adult specimens observed under laboratory conditions were collected in the field, shortly after leaving their overwintering sites in the soil. Our results showed that feeding on the leaves of Q. robur and Q. rubra had the greatest positive effects on the life span, body weight and fecundity of the studied cockchafer adults. M. melolontha females reared on the leaves of B. pendula laid no eggs. The leaves of A. platanoides constituted an adequate food source for the development of M. hippocastani. P. silvestris inflorescences proved to be the right food only for M. melolontha females. M. hippocastani adults feeding on T. cordata and B. pendula were characterized by a short life, decreasing body weight in the first days of observation and low fertility.