Academic literature on the topic 'Habitat manipulation'

Abstract The matching habitat choice hypothesis posits that individuals actively choose those microhabitats that best match their specific phenotype to maximize fitness. Despite the profound implications, matching habitat choice has not been unequivocally demonstrated. We conducted two experiments to examine the impact of pigmentation pattern in the color polymorphic pygmy grasshopper Tetrix subulata on habitat choice in a laboratory thermal mosaic arena. We found no behavioral differences in the thermal mosaic among pygmy grasshoppers belonging to either pale, intermediate or dark natural color morphs. However, after manipulating the grasshoppers’ phenotype, the utilization through time of warmer and colder parts of the arena was different for black-painted and white-painted individuals. White-painted individuals used warmer parts of the arena, at least during the initial stage of the experiment. We conclude that microhabitat choice represents a form of behavioural plasticity. Thus, even if the choice itself is flexible and not genetically determined, it can still lead to spatial genetic structure in the population because the phenotypes themselves may be genetically mediated.

Two widely-recognised hypotheses propose that increases in fish abundance at artificial reefs are caused by: (a) the attraction and redistribution of existing individuals; and/or (b) the addition of new individuals by production. Inadequate experimental designs compromised by a lack of sufficient replication and/or spatial interspersion of reefs with controls have prevented researchers from distinguishing between attraction and production. Infrequent sampling has also led to insufficient temporal coverage of life history-driven variations in fish abundance and biomass at reefs. Detection and resolution of these trends, together with incorporation of fish age/length data, and the use of techniques such as stable isotope analysis to infer trophic link(s) between reef residents and potential sources of epibenthic nutrition at reefs should help demonstrate mechanisms underlying attraction and/or production. Given that fish numbers tend to increase after artificial reef deployments, artificial reefs have been proposed as a means by which fish stocks could be enhanced by providing new habitat in areas where natural habitat vital for feeding, shelter and reproduction have been removed, such as residential canals. The purpose of my study was to investigate whether or not artificial reefs could be used to enhance fish production within residential canals. Five reefs were deployed into Lake Rumrunner on the Gold Coast in southeast Queensland, Australia (28°02’59”S, 153°25’19”E). Reefs were interspersed among five soft sediment (control) sites of similar depth. Fish assemblages at reefs, controls and shoreline jetties were quantitatively sampled using a modified seine pop net. Very few fish were recorded at controls, but fish abundance and biomass increased dramatically at reefs shortly after deployment, stabilising at levels above that of shoreline jetties. Reefs and jetties accommodated different fish assemblages and assemblage structure varied through time. Multivariate analyses indicated that the fish assemblage at jetties within Lake Rumrunner differed from assemblages at jetties in adjacent lakes in terms of biomass composition, accommodating numerous individuals of small-bodied species. The fish assemblage at reefs featured individuals of large-bodied species and occasional, itinerant individuals of species typical of offshore subtidal reefs. Among co-occurring (reef and jetty) fish species, strong differences in the distribution of Monodactylus argenteus (Monodactylidae) between reefs, jetties and controls suggested possible new production driven by reef deployment. Abundance and biomass of M. argenteus was significantly greater at reefs relative to controls (where no fish were caught) and jetties at all times after deployment. Individuals were consistently larger on reefs than on jetties. Analyses of length-frequency distributions through time indicated the size of individuals differed from one sampling time to the next for most sampling times at reefs, possibly representing cohort growth and movement through time...
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment
Science, Environment, Engineering and Technology
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Trichogramma carverae Oatman and Pinto is mass-released for biological control of the leafroller pest, light brown apple moth, Epiphyas postvittana (Walker) in Australian vineyards. Parasitoid performance can, however, be constrained by a lack of suitable adult food and no information is available on the effect of nectar on the parasitism and longevity of T. carverae. To address this, the effect of alyssum, Lobularia maritima (L.) flowers on E. postvittana parasitism was studied in a vineyard experiment with and without releases of T. carverae. Egg parasitoid activity was assessed with E. postvittana egg 'sentinel cards' and no parasitism was recorded in plots without T. carverae releases. Where T. carverae were released, there was no significant enhancement of parasitism by the presence of L. maritima flowers. Three hypotheses were subsequently tested to account for the lack of an effect: (i) T. carverae does not benefit from L. maritima nectar, (ii) T. carverae was feeding on nectar from other flowering plants (weeds) present in the vineyard, (iii) T. carverae was feeding on sugars from ripe grapes. A growth-cabinet experiment using potted L. maritima plants with and without flowers did not support hypothesis one. No parasitism was recorded after day two for T. carverae caged without flowers whilst parasitism occured until day eight in the presence of flowers. A laboratory experiment with common vineyard weeds (Trifolium repens, Hypochoeris radicata, Echium plantagineum) as well as L. maritima did not support hypothesis one but gave partial support to hypothesis two. Survival of T. carverae was enhanced to a small but statistically significant extent in vials with intact flowers of L. maritima, white clover (T. repens) and catsear (H. radicata) but not in vials with flowering shoots of these species from which flowers and flowering buds had been removed. Paterson's curse (E. plantagineum) flowers had no effect on T. carverae survival. In a laboratory study, punctured grapes significantly enhanced T. carverae survival compared with a treatment without grapes, supporting hypothesis three. Trichogramma carverae performance in the field experiment was probably also constrained by relatively cool and wet weather. Further work on the enhancement of T. carverae efficacy by L. maritima and other carbohydrate sources is warranted. Greenhouse and field experiments were conducted to investigate whether T. carverae benefit from different groundcover plant species. Ten T. carverae adults (<24h after eclosion) were caged with different groundcover species and a control with no plant materials. Epiphyas postvittana egg sentinel cards were used to measure parasitism and longevity was recorded visually. Survival and realised parasitism of T. carverae was significantly higher in L. maritima than in Brassica juncea, Coriandrum sativum, shoots of these species from which flowers had been removed and nil control treatments. A similar experiment with Fagopyrum esculentum (with- and without-flowers) and a control treatment showed that survival was significantly higher in intact F. esculentum than in without-flower and control treatments. There was no significant treatment effect on parasitism in the early stages of that experiment, though parasitism was recorded in the presence of F. esculentum flowers for 12 days, compared with 6 days in other treatments. Higher parasitism was observed in intact Borago officinalis than in the flowerless shoot, water only and no plant material control treatments in a third experiment. There was no significant treatment effect on parasitism. Fitted exponential curves for survival data differed significantly in curvature in the first, second and third experiments but the slope was a non-significant parameter in the second and third experiments. In a second series of laboratory experiments, one male and one female T. carverae were caged with groundcover species to investigate male and female longevity and daily fecundity. Both male and female longevity in F. esculentum and L. maritima treatments were significantly higher than on shoots of these species from which flowers had been removed, and than in the control treatments. Daily fecundity was significantly greater in the intact L. maritima treatment than in all other treatments. Fitted exponential curves for daily fecundity differed significantly in position and slope but not in curvature. There was no significant treatment effect on longevity or parasitism when a male and female were caged with intact B. juncea, B. officinalis or without-flower of these species, nor in the treatment with no plant materials. No parasitism was observed in a survey of naturally occurring egg parasitoids on two sites close to Orange and Canowindra in New South Wales, illustrating the importance of mass releases of T. carverae in biological control of E. postvittana. In an experiment on the Canowindra site, parasitism was significantly higher on day one and day two after T. carverae release when with-flower treatments were compared with without-flower treatments. Parasitism was significantly higher in the F. esculentum treatment than in C. sativum, L. maritima, vegetation without-flowers and control treatments on these dates. On day five, parasitism was higher in C. sativum than in all other treatments. There was no significant increase in parasitism in a second experiment conducted on the Orange site. Coriandrum sativum, F. esculentum and L. maritima appear to be suitable adult food sources for T. carverae and offer some scope for habitat manipulation in vineyards The adults of many parasitoid species require nectar for optimal fitness but very little is known about flower recognition. Flight cage experiments showed that the adults of T. carverae benefited from L. maritima bearing white flowers to a greater extent than was the case for light pink, dark pink or purple flowered cultivars, despite all cultivars producing nectar. Survival and realised parasitism on non-white flowers were no greater than when the parasitoids were caged on L. maritima shoots from which flowers had been removed. The possibility that differences between L. maritima cultivars were due to factors other than flower colour, such as nectar quality, was excluded by dyeing white L. maritima flowers by placing the roots of the plants in 5% food dye (blue or pink) solution. Survival of T. carverae was lower on dyed L. maritima flowers than on undyed white flowers. Mixing the same dyes with honey in a third experiment conducted in the dark showed that the low level of feeding on dyed flowers was unlikely to be the result of olfactory or gustatory cues. Flower colour appears, therefore, to be a critical factor in the choice of plants used to enhance biological control, and is likely to also be a factor in the role parasitoids play in structuring invertebrate communities. Provision of nectar producing plants to increase the effectiveness of biological control is one aspect of habitat manipulation, but care needs to be taken to avoid the use of plant species that may benefit pest species. Greenhouse experiments were conducted to investigate whether the adult E. postvittana and larvae benefit from nectar producing groundcover species. Newly emerged E. postvittana adults were caged with different groundcover species and a honey-based artificial adult diet. The longevity of male and female E. postvittana when caged with shoots of borage (B. officinalis) and buckwheat (F. esculentum) bearing flowers was as long as when fed a honey-based artificial diet. This effect was not evident when caged with shoots of these plants from which flowers had been removed. Longevity was significantly lower than in the artificial diet treatment when caged with coriander (C. sativum) or alyssum (L. maritima) irrespective of whether flowers were present or not. There was no significant treatment effect on the lifetime fecundity of E. postvittana. A second experiment with mustard (B. juncea) (with- and without-flowers), water only and honey-based artificial adult diet showed no significant treatment effects on the longevity of male and female E. postvittana or on the lifetime fecundity of E. postvittana. The anomalous lack of a difference between the water and honey-based diet treatments precludes making conclusions on the value of B. juncea for E. postvittana. Two greenhouse experiments were conducted to evaluate the effects of groundcover species on the larval development of E. postvittana. In the first experiment, larval mortality was significantly higher in C. sativum, and L. maritima than in B. juncea, B. officinalis and white clover (T. repens) a known host of E. postvittana. Coriandrum sativum and L. maritima extended the larval period. In B. juncea and B. officinalis, mortality did not differ from that in T. repens. In F. esculentum, larval mortality was significantly higher than in T. repens. A short larval period was observed on B. juncea, B. officinalis and F. esculentum. Fitted exponential curves for larval mortality differed significantly in curvature between plant treatments. Similarly, successful pupation was significantly lower in C. sativum, F. esculentum and L. maritima than in T. repens. The percentage of successful pupation in B. juncea and B. officinalis did not differ from F. esculentum and T. repens. Fitted exponential curves for pupation differed significantly in curvature. A similar trend was observed in a second experiment with potted plants. The overall results suggest that C. sativum and L. maritima denied benefit to E. postvittana adults and larvae, so could be planted as vineyard groundcover with minimal risk of exacerbating this pest. Overall results suggest that T. carverae require nutrients to reach their full reproductive potential and flowers provide such nutrients. Lobularia maritima and C. sativum may be considered 'selective food plants' for T. carverae whereas F. esculentum appears to be a 'non-selective food plant'; both T. carverae and E. postvittana benefited from it. Fruits such as grapes can be used as food resources in habitat manipulation and this merits further research. This result also suggests that within species flower colour is an important factor for flower selection in habitat manipulation.

Trichogramma carverae Oatman and Pinto is mass-released for biological control of the leafroller pest, light brown apple moth, Epiphyas postvittana (Walker) in Australian vineyards. Parasitoid performance can, however, be constrained by a lack of suitable adult food and no information is available on the effect of nectar on the parasitism and longevity of T. carverae. To address this, the effect of alyssum, Lobularia maritima (L.) flowers on E. postvittana parasitism was studied in a vineyard experiment with and without releases of T. carverae. Egg parasitoid activity was assessed with E. postvittana egg �sentinel cards� and no parasitism was recorded in plots without T. carverae releases. Where T. carverae were released, there was no significant enhancement of parasitism by the presence of L. maritima flowers. Three hypotheses were subsequently tested to account for the lack of an effect: (i) T. carverae does not benefit from L. maritima nectar, (ii) T. carverae was feeding on nectar from other flowering plants (weeds) present in the vineyard, (iii) T. carverae was feeding on sugars from ripe grapes. A growth-cabinet experiment using potted L. maritima plants with and without flowers did not support hypothesis one. No parasitism was recorded after day two for T. carverae caged without flowers whilst parasitism occured until day eight in the presence of flowers. A laboratory experiment with common vineyard weeds (Trifolium repens, Hypochoeris radicata, Echium plantagineum) as well as L. maritima did not support hypothesis one but gave partial support to hypothesis two. Survival of T. carverae was enhanced to a small but statistically significant extent in vials with intact flowers of L. maritima, white clover (T. repens) and catsear (H. radicata) but not in vials with flowering shoots of these species from which flowers and flowering buds had been removed. Paterson�s curse (E. plantagineum) flowers had no effect on T. carverae survival. In a laboratory study, punctured grapes significantly enhanced T. carverae survival compared with a treatment without grapes, supporting hypothesis three. Trichogramma carverae performance in the field experiment was probably also constrained by relatively cool and wet weather. Further work on the enhancement of T. carverae efficacy by L. maritima and other carbohydrate sources is warranted. Greenhouse and field experiments were conducted to investigate whether T. carverae benefit from different groundcover plant species. Ten T. carverae adults (<24h after eclosion) were caged with different groundcover species and a control with no plant materials. Epiphyas postvittana egg sentinel cards were used to measure parasitism and longevity was recorded visually. Survival and realised parasitism of T. carverae was significantly higher in L. maritima than in Brassica juncea, Coriandrum sativum, shoots of these species from which flowers had been removed and nil control treatments. A similar experiment with Fagopyrum esculentum (with- and without-flowers) and a control treatment showed that survival was significantly higher in intact F. esculentum than in without-flower and control treatments. There was no significant treatment effect on parasitism in the early stages of that experiment, though parasitism was recorded in the presence of F. esculentum flowers for 12 days, compared with 6 days in other treatments. Higher parasitism was observed in intact Borago officinalis than in the flowerless shoot, water only and no plant material control treatments in a third experiment. There was no significant treatment effect on parasitism. Fitted exponential curves for survival data differed significantly in curvature in the first, second and third experiments but the slope was a non-significant parameter in the second and third experiments. In a second series of laboratory experiments, one male and one female T. carverae were caged with groundcover species to investigate male and female longevity and daily fecundity. Both male and female longevity in F. esculentum and L. maritima treatments were significantly higher than on shoots of these species from which flowers had been removed, and than in the control treatments. Daily fecundity was significantly greater in the intact L. maritima treatment than in all other treatments. Fitted exponential curves for daily fecundity differed significantly in position and slope but not in curvature. There was no significant treatment effect on longevity or parasitism when a male and female were caged with intact B. juncea, B. officinalis or without-flower of these species, nor in the treatment with no plant materials. No parasitism was observed in a survey of naturally occurring egg parasitoids on two sites close to Orange and Canowindra in New South Wales, illustrating the importance of mass releases of T. carverae in biological control of E. postvittana. In an experiment on the Canowindra site, parasitism was significantly higher on day one and day two after T. carverae release when with-flower treatments were compared with without-flower treatments. Parasitism was significantly higher in the F. esculentum treatment than in C. sativum, L. maritima, vegetation without-flowers and control treatments on these dates. On day five, parasitism was higher in C. sativum than in all other treatments. There was no significant increase in parasitism in a second experiment conducted on the Orange site. Coriandrum sativum, F. esculentum and L. maritima appear to be suitable adult food sources for T. carverae and offer some scope for habitat manipulation in vineyards The adults of many parasitoid species require nectar for optimal fitness but very little is known about flower recognition. Flight cage experiments showed that the adults of T. carverae benefited from L. maritima bearing white flowers to a greater extent than was the case for light pink, dark pink or purple flowered cultivars, despite all cultivars producing nectar. Survival and realised parasitism on non-white flowers were no greater than when the parasitoids were caged on L. maritima shoots from which flowers had been removed. The possibility that differences between L. maritima cultivars were due to factors other than flower colour, such as nectar quality, was excluded by dyeing white L. maritima flowers by placing the roots of the plants in 5% food dye (blue or pink) solution. Survival of T. carverae was lower on dyed L. maritima flowers than on undyed white flowers. Mixing the same dyes with honey in a third experiment conducted in the dark showed that the low level of feeding on dyed flowers was unlikely to be the result of olfactory or gustatory cues. Flower colour appears, therefore, to be a critical factor in the choice of plants used to enhance biological control, and is likely to also be a factor in the role parasitoids play in structuring invertebrate communities. Provision of nectar producing plants to increase the effectiveness of biological control is one aspect of habitat manipulation, but care needs to be taken to avoid the use of plant species that may benefit pest species. Greenhouse experiments were conducted to investigate whether the adult E. postvittana and larvae benefit from nectar producing groundcover species. Newly emerged E. postvittana adults were caged with different groundcover species and a honey-based artificial adult diet. The longevity of male and female E. postvittana when caged with shoots of borage (B. officinalis) and buckwheat (F. esculentum) bearing flowers was as long as when fed a honey-based artificial diet. This effect was not evident when caged with shoots of these plants from which flowers had been removed. Longevity was significantly lower than in the artificial diet treatment when caged with coriander (C. sativum) or alyssum (L. maritima) irrespective of whether flowers were present or not. There was no significant treatment effect on the lifetime fecundity of E. postvittana. A second experiment with mustard (B. juncea) (with- and without-flowers), water only and honey-based artificial adult diet showed no significant treatment effects on the longevity of male and female E. postvittana or on the lifetime fecundity of E. postvittana. The anomalous lack of a difference between the water and honey-based diet treatments precludes making conclusions on the value of B. juncea for E. postvittana. Two greenhouse experiments were conducted to evaluate the effects of groundcover species on the larval development of E. postvittana. In the first experiment, larval mortality was significantly higher in C. sativum, and L. maritima than in B. juncea, B. officinalis and white clover (T. repens) a known host of E. postvittana. Coriandrum sativum and L. maritima extended the larval period. In B. juncea and B. officinalis, mortality did not differ from that in T. repens. In F. esculentum, larval mortality was significantly higher than in T. repens. A short larval period was observed on B. juncea, B. officinalis and F. esculentum. Fitted exponential curves for larval mortality differed significantly in curvature between plant treatments. Similarly, successful pupation was significantly lower in C. sativum, F. esculentum and L. maritima than in T. repens. The percentage of successful pupation in B. juncea and B. officinalis did not differ from F. esculentum and T. repens. Fitted exponential curves for pupation differed significantly in curvature. A similar trend was observed in a second experiment with potted plants. The overall results suggest that C. sativum and L. maritima denied benefit to E. postvittana adults and larvae, so could be planted as vineyard groundcover with minimal risk of exacerbating this pest. Overall results suggest that T. carverae require nutrients to reach their full reproductive potential and flowers provide such nutrients. Lobularia maritima and C. sativum may be considered �selective food plants� for T. carverae whereas F. esculentum appears to be a �non-selective food plant�; both T. carverae and E. postvittana benefited from it. Fruits such as grapes can be used as food resources in habitat manipulation and this merits further research. This result also suggests that within species flower colour is an important factor for flower selection in habitat manipulation.

Paropsis atomaria Olivier (Coleoptera: Chrysomelidae: Paropsini), is a major pest of commercially grown eucalypts in South-East Queensland. Current management of paropsine beetles involves regular inspection and the application of chemical sprays if defoliation is severe. However, non-chemical control of plantation pests is highly desirable given the requirement to certify forest practices for sustainability, and community concerns over the use of pesticides. One way of reducing pesticide use is through conservation biological control, which requires detailed knowledge of the life history of the pest and its natural enemies. This thesis documents aspects of P. atomaria phenology, including life tables, sex ratios and damage estimates; identifies the predators, parasites, and egg and larval parasitoids of P. atomaria; and examines the ecology of the most promising natural enemy, Neopolycystus Girault sp. (Hymenoptera: Pteromalidae) in South-East Queensland. P. atomaria adults are active from September until April and can complete up to four generations in a season. Field mortality between egg and fourth instar larvae is approximately 94%. A large proportion of this mortality can be attributed to natural enemies. The most abundant predators in eucalypt plantations were spiders, comprising 88% of all predators encountered. Egg parasitoids exerted the greatest influence on P. atomaria populations, emerging from around 50% of all egg batches, and were responsible for mortality of almost one third of all eggs in the field. Only about one percent of larvae were parasitised in the field, in contrast to paropsine pests in temperate Australia, where egg parasitism rates are low and larval parasitism rates high. Neopolycystus sp. was the only primary parasitoid reared from P. atomaria eggs, along with three hyperparasitoid species; Baeoanusia albifunicle Girault (Encyrtidae), Neblatticida sp. (Encyrtidae) and Aphaneromella sp. (Platygasteridae). This is the first record of B. albifunicle hyperparasitising Neopolycystus spp. B. albifunicle emerged from one-third of all parasitised egg batches and could pose a potential problem to the efficacy of Neopolycystus sp. as a biological control agent. However, within egg batches, hyperparasitoids rarely killed all Neopolycystus sp. with only 9% of hyperparasitised egg batches failing to produce any primary parasitoids. Total field mortality of P. atomaria through direct and indirect effects of parasitism by Neopolycystus sp. was 28%. The proportion of egg batches parasitised increased with exposure time in the field, but within-batch parasitism rate did not. In general, there was no significant correlation between parasitism rates and distance from landscape features (viz. water sources and native forest).

Paropsis atomaria Olivier (Coleoptera: Chrysomelidae: Paropsini), is a major pest of commercially grown eucalypts in South-East Queensland. Current management of paropsine beetles involves regular inspection and the application of chemical sprays if defoliation is severe. However, non-chemical control of plantation pests is highly desirable given the requirement to certify forest practices for sustainability, and community concerns over the use of pesticides. One way of reducing pesticide use is through conservation biological control, which requires detailed knowledge of the life history of the pest and its natural enemies. This thesis documents aspects of P. atomaria phenology, including life tables, sex ratios and damage estimates; identifies the predators, parasites, and egg and larval parasitoids of P. atomaria; and examines the ecology of the most promising natural enemy, Neopolycystus Girault sp. (Hymenoptera: Pteromalidae) in South-East Queensland. P. atomaria adults are active from September until April and can complete up to four generations in a season. Field mortality between egg and fourth instar larvae is approximately 94%. A large proportion of this mortality can be attributed to natural enemies. The most abundant predators in eucalypt plantations were spiders, comprising 88% of all predators encountered. Egg parasitoids exerted the greatest influence on P. atomaria populations, emerging from around 50% of all egg batches, and were responsible for mortality of almost one third of all eggs in the field. Only about one percent of larvae were parasitised in the field, in contrast to paropsine pests in temperate Australia, where egg parasitism rates are low and larval parasitism rates high. Neopolycystus sp. was the only primary parasitoid reared from P. atomaria eggs, along with three hyperparasitoid species; Baeoanusia albifunicle Girault (Encyrtidae), Neblatticida sp. (Encyrtidae) and Aphaneromella sp. (Platygasteridae). This is the first record of B. albifunicle hyperparasitising Neopolycystus spp. B. albifunicle emerged from one-third of all parasitised egg batches and could pose a potential problem to the efficacy of Neopolycystus sp. as a biological control agent. However, within egg batches, hyperparasitoids rarely killed all Neopolycystus sp. with only 9% of hyperparasitised egg batches failing to produce any primary parasitoids. Total field mortality of P. atomaria through direct and indirect effects of parasitism by Neopolycystus sp. was 28%. The proportion of egg batches parasitised increased with exposure time in the field, but within-batch parasitism rate did not. In general, there was no significant correlation between parasitism rates and distance from landscape features (viz. water sources and native forest).

My research provided new information concerning the management, ecology, and conservation of greater sage-grouse (Centrocercus urophasianus). I report the results of an experiment using strategic intensive sheep grazing to enhance the quality of greater sage-grouse brood-rearing habitat. Although forb cover, an important component of brood-rearing habitat, responded positively to the grazing treatment, the response of other habitat variables was suppressed because the plots were not protected from domestic and wild herbivores during the years following the treatments. Measurements taken in grazing exclosures confirmed that herbivory by both large and small animals had significant impacts on vegetation. However, despite the suppressed habitat response, sage-grouse preferred the treated plots over the controls. In another chapter, I modeled survival rates of sage-grouse chicks to 42-days of age. Average chick survival across my study was high (39%). Survival varied across years and was affected by demographic, behavioral, and habitat factors. The top habitat model indicated that chick survival was positively related to grass cover and was higher in areas dominated by black sagebrush (Artemisia nova) than in big sagebrush (A. tridentata). The top model with demographic/behavioral factors indicated that survival was affected by interactions between hen age and brood mixing as well as between hatch date and brood mixing. In my last chapter I report on a survey of Utah sage-grouse hunter motivations and satisfaction. In 2008 and 2009 I surveyed over 600 sage-grouse hunters in Utah to determine why they chose to apply for sage-grouse hunting permits and what factors contributed to a satisfactory hunting experience. Originally, I had hypothesized that the impending Endangered Species Act listing petition for greater sage-grouse motivated hunters to pursue the species before they lost the opportunity. This hypothesis was not supported by the data. The majority of hunters indicated that they chose to hunt sage-grouse because it was a tradition or because it provided an opportunity to spend time outdoors with family. Additionally, Utah sage-grouse hunter satisfaction was influenced by whether or not the hunter was successful in harvesting at least one bird.

Le specie aliene invasive sono specie animali o vegetali che molto spesso vengono introdotte involontariamente in ecosistemi non autoctoni, con impatto negativo per l'ambiente e le attività umane. La Drosophila suzukii Matsumura (Diptera: Drosophilidae), nota anche come Spotted Wing Drosophila, è una specie aliena invasiva originaria dell'Asia orientale, che si è ampiamente diffusa nelle Americhe e in Europa, dove è divenuta un grave parassita delle colture frutticole, causando notevoli perdite economiche. In Trentino la prima segnalazione di questo insetto su ospiti coltivati è avvenuta nel 2009. La sua rapida diffusione in tutto il mondo è attribuita a delle caratteristiche peculiari di D. suzukii, come l'ovopositore seghettato che gli consente di deporre le uova in frutti sani in maturazione, l’ampia gamma di piante ospiti, l’elevata fecondità e la tolleranza nei confronti di un ampio spettro di condizioni climatiche, fattori che ne ha aumentano significativamente l'invasività. Gli attuali approcci per il controllo di D. suzukii si basano principalmente su strategie di gestione integrata dei parassiti, tra cui il controllo chimico, le reti anti-insetto, la cattura massale e pratiche culturali, come la potatura delle chiome, l'irrigazione a goccia e il sollecito allontanamento della frutta infestata dai campi nel corso della raccolta. Analogamente ad altri parassiti invasivi, D. suzukii non viene efficacemente controllata da parte dei nemici naturali nelle aree invase, consentendogli di riprodursi rapidamente e diffondersi illimitatamente, aumentando la pressione dei parassiti sulle coltivazioni. Il controllo biologico inondativo e quello classico, sono in corso di valutazione e potrebbero diventare dei promettenti candidati per limitare i focolai stagionali di D. suzukii e i relativi danni alle colture. Tuttavia, nonostante i notevoli passi in avanti sulle conoscenze della biologia e l'ecologia di D. suzukii, questo insetto rappresenta ancora una seria minaccia per le colture e vi è la necessità di ulteriori studi al fine di aggiornare gli strumenti di gestione a disposizione per far fronte a questo importante parassita delle colture. Nel corso dei monitoraggi faunistici in provincia di Trento, abbiamo riscontrato e segnalato per la prima volta in Europa la presenza del parassitoide larvale asiatico Leptopilina japonica Novkovic & Kimura (Hymenoptera: Figitidae), uno dei più efficaci nemici naturali di D. suzukii nell’areale nativo. L’esteso monitoraggio in campo successivo al primo ritrovamento ha permesso di stabilire l'elevata capacità di questo parassitoide di parassitare il suo ospite su un ampio spettro di specie vegetali, appartenenti a diverse famiglie tassonomiche come Moraceae, Rosaceae, Glossulariaceae, Rhamnaceae, Cornaceae, Ericaceae, Phytolaccaceae, Dioscoreaceae, Adoxaceae e Solanaceae. Questi risultati offrono nuove prospettive per il controllo biologico di D. suzukii nelle aree di recente introduzione, anche per quanto concerne i futuri programmi di controllo biologico classico con Ganaspis brasiliensis Ihering (Hymenoptera: Figitidae). Il controllo biologico per mezzo di parassitoidi o predatori può essere facilmente integrato con la tecnica dell'insetto sterile (SIT), potenziando il controllo sulle popolazioni di parassiti. Tuttavia, il successo della SIT è in gran parte influenzato dal sistema riproduttivo del parassita bersaglio, per cui l’approfondimento dei tratti riproduttivi è un prerequisito fondamentale per verificare l’effettiva applicabilità di questa tecnica di controllo. L'analisi della paternità mediante la genotipizzazione di loci microsatellite della progenie di femmine catturate in natura, ha rilevato elevati livelli di paternità multipla nelle covate genotipizzate, stabilendo il comportamento poliandro di D. suzukii, sebbene non sia stata rilevata alcuna distorsione della paternità nell'allocazione dello sperma, ovvero in termini di maschio prevalenza. Oltre al controllo biologico e alla SIT, le strategie basate sulla manipolazione dell'habitat potrebbero utilmente integrare le comuni pratiche culturali messe in atto dagli agricoltori per il controllo di D. suzukii. Le nostre prove in campo hanno dimostrato che la consociazione con Mentha x piperita (Menta piperita, Lamiaceae) Origanum vulgare L. (Origano, Lamiaceae), Thymus vulgaris L. (Timo, Lamiaceae) o Ocimum gratissimum L. (Basilico africano, Lamiaceae), non risulta avere un impatto positivo nel limitare i danni causati da D. suzukii su colture di mirtillo, mentre la realizzazione di una bordura di Prunus padus (ciliegio europeo, Rosacee) si è dimostrata in grado di ridurre l'infestazione su di una coltura di lampone, agendo come pianta trappola. Inoltre, il controllo biologico conservativo mediante la tecnica dell’augmentorium può offrire un’ulteriore integrazione agli strumenti di controllo. Abbiamo infatti potuto osservare come il nostro prototipo si è dimostrato adatto per una sua applicazione su D. suzukii e sui relativi parassitoidi indigeni, favorendo la sanificazione delle colture dai frutti infestati e sostenendo i più comuni parassitoidi pupali. Con questa ricerca abbiamo inteso verificare l’efficacia di nuovi strumenti di controllo di D. suzukii, quali il controllo biologico, sia conservativo che classico, la SIT e la manipolazione dell'habitat, la cui opportuna integrazione offrirebbe la possibilità di implementare un approccio agroecologico di gestione di questo parassita invasivo.
Invasive alien species are animal or plant species that are very often unintentionally introduced into non-native ecosystems, with negative impact for the environment and human activities. Drosophila suzukii Matsumura (Diptera: Drosophilidae), also known as Spotted Wing Drosophila, is an invasive alien species native to East Asia, which has widely established in Americas and Europe, where it has become a serious pest of fruit crops, causing considerable economic losses. In Trentino Province the first oviposition on crop hosts was reported in 2009. The rapid worldwide spread is attributed to peculiar features of D. suzukii, such as the serrated ovipositor that allows it to oviposit into healthy ripening fruits, broad host plants range, high fecundity potential and tolerance of wide climatic conditions. Current approaches for controlling D. suzukii rely primarily on integrated pest management strategies, including chemical control, insect-proof netting, mass trapping and cultural practices, such as canopy pruning, drip irrigation, and field sanitation. Similarly to other invasive pest, D. suzukii lacks of an effective suppression by natural enemies in the recently invaded areas, enabling it to reproduce quickly and spread unlimitedly, increasing pest pressure on cropping systems. Augmentative and classical biological control are still under investigation as promising candidates for limiting D. suzukii seasonal outbreaks and related damage on crops. However, despite the remarkable steps forward in the knowledge on biology and ecology of D. suzukii, it is still a serious threat to crops and further investigations are urgently required in order to update the availability of management tools to cope with this crop pest. During our faunistic surveys in Trentino province, we found and reported for the first time in Europe, the presence of the Asian larval parasitoid Leptopilina japonica Novkovic & Kimura (Hymenoptera: Figitidae), one of the most effective natural enemies of D. suzukii in the native range. The following extensive field monitoring based on fruit sampling revealed the high capacity of this parasitoid to parasitize its host on a complex of several plant species, belonging to Moraceae, Rosaceae, Glossulariaceae, Rhamnaceae, Cornaceae, Ericaceae, Phytolaccaceae, Dioscoreaceae, Adoxaceae and Solanaceae. These findings offer new perspective for biological control of D. suzukii in the introduced areas, also in relation to the classical biological control programmes with Ganaspis brasiliensis Ihering (Hymenoptera: Figitidae). Biological control by means of parasitoids or predators can be easily integrated with sterile insect technique (SIT), synergizing the control effects on pest population. Nevertheless, the success of SIT is largely influences by mating system of target pest, thus deepen reproductive traits is a fundamental step forward. Paternity analysis by means of microsatellite loci genotyping of the progeny of wild-caught females, detected high levels of multiple paternity in genotyped broods, stating the polyandrous behaviour of D. suzukii, but no found evidence of a strong paternity skew in sperm allocation, in terms of prevailing male. Beyond biological control and SIT, habitat manipulation strategies may further help local farmers to deal with D. suzukii in addition to common applied cultural practices. Our field trials have shown that intercropping with Mentha x piperita (Peppermint, Lamiaceae) Origanum vulgare L. (Oregano, Lamiaceae), Thymus vulgaris L. (Thyme, Lamiaceae), or Ocimum gratissimum L. (African basil, Lamiaceae), has no effect in limiting the damage of D. suzukii on blueberries, whilst hedges of Prunus padus (European bird cherry, Rosaceae) was able to reduce the infestation on raspberry, having a potential role as dead-end trap plant for crop protection against D. suzukii. Furthermore, conservative biological control by means of the augmentorium technique may be further explored, as we observed that our prototype has shown to be well adapted to D. suzukii and its indigenous parasitoids, favouring crop sanitation from infested fruits and sustaining the most common Drosophila pupal parasitoids. This research aims to give new insights for a more sustainable management of D. suzukii, offering new solutions that, by combining biological control, both conservative and classical, SIT and habitat manipulation, may move towards an agroecological approach for controlling this invasive pest.

Abstract Diverse biotic interactions between non-native plant species and other species from all taxonomic groups are crucial mediators of the dynamics of plant invasions. This chapter reviews the key hypotheses in invasion ecology that invoke biotic interactions to explain aspects of plant invasion dynamics. We examine the historical context of these hypotheses and assess the evidence for accepting or rejecting their predictions. Most hypotheses invoke antagonistic interactions, mainly competition, predation, herbivory interactions and the role of pathogens. Only in the last two decades have positive (facilitative/mutualistic) interactions been explicitly included in invasion biology theory (as in ecological theory in general). Much information has accumulated in testing hypotheses relating to biotic resistance and Enemy Release Theory, although many of the emerging generalizations are still contentious. There is growing consensus that other drivers of plant invasion success, such as propagule pressure and disturbance, mediate the outcome of biotic interactions, thereby complicating our ability to make predictions, but these have rarely been assessed in both native and adventive ranges of non-native invasive species. It is also widely acknowledged that biogeographic comparisons, more than common garden experiments, are needed to shed light on many of the contradictory results. Contrasting findings have also emerged in exploring the roles of positive interactions. Despite strong evidence that such interactions are crucial in many communities, more work is needed to elucidate the factors that influence the relative importance of positive and negative interactions in different ecosystems. Different types of evidence in support of invasional meltdown have emerged for diverse habitats and across spatial scales. In light of increasing evidence that biotic indirect effects are crucial determinants of the structure, dynamics and evolution of ecological communities, both direct and indirect interactions involving native and non-native species must be considered to determine how they shape plant invasion patterns and the ecological impacts of non-native species on recipient communities. Research that examines both biotic interactions and the factors that mediate their strength and alter interaction outcomes is needed to improve our ability to predict the effects of novel interactions between native and non-native species, and to envisage how existing invaded communities will respond to changing environmental conditions. Many opportunities exist for manipulating biotic interactions as part of integrated control strategies to reduce the extent, density and impacts of non-native plant invasions. These include the introduction of species from the native range of the non-native plant for biological control, diverse manipulations of plant - herbivore interactions and many types of interaction to enhance biotic resistance and steer vegetation recovery following non-native plant control.

<em>Abstract</em>.—Stream restoration techniques in the southeastern United States have focused mostly on habitat manipulation. However, using simple and aggressive methodologies is necessary to promote cost effective methods of restoring habitat. A review of stream restoration practices is provided, with two detailed and different restoration scenarios presented, followed by a discussion on the effectiveness of these methods and lessons learned to help facilitate a range of options during the development of restoration goals and objectives.

The citizens nowadays are often born and raised in well developed urban areas and have rarely, even never experienced the difficulties that wildlife are suffering from due to human actions. They are likely to possess sympathy, but never do these individuals are aware of how their deeds may affect the living of other species on planet Earth [1]. However, if someone reveals the bloody truth to the people, they are likely to change for the greater good. In this paper, we mainly used unity modeling and java programming skills to develop an animal simulation game in order to show the damage done by mankind and resonate the feeling of empathy so the players may alter their actions to preserve the environment [2][3]. The player starts the game as an animal figure in a randomly generated map. The player will control the animal to move around to consume water and food for survival. Meanwhile, the animal must avoid the invasion of human poison lands closing in on the habitats for this figure. Eventually, the player will starve or be poisoned and fail to survive. By setting this result, we hope to arouse the sympathy in hearts and lead to some alteration to a person’s habits.

Though urban areas globally cover only about 3% of the earth’s land surface, the UAGs have received a little attention with regards to their ecological facilities. The main aim of this study remains to assess and compare the choice of ecological management options, which guidelines to improvement of environmental-friendly forms of gardening provided by two different UAGs, e.g. Užuovėja (U) and Nemunas (N) in Kaunas distr., central Lithuania. The gardeners were interviewed to identify their preference of different gardening means and reasons for their ecological choices using a questionnaire (n = 60) containing questions about gardening behaviour were surveyed. The interviewed gardeners differ in their commitment and motivation, their agro-ecological practices, and their habits when growing fruits and vegetables. Ecological means, e.g. self-generated compost, turf and organic fertilizer were applied in 43.3-16.7; 16.7-6.7 and 43.3-16.7% in UAGs N and U, respectively. Only 3 or 10% (N) and 4 or 13.3% (U), of respondent regularly used chemical control means regularly. Unfortunately, only 11 or 36.7% (N) and 4 or 13.3% (U) of respondents regularly and sometimes used biological control means. While 7 or 23.3% (N) and 1 or 3.3% (U) of respondents apply biological control means on rare occasion. The large amount of gardeners’, i.e. 63% (N) and 80% (U) employs the natural water resources. This study shows that choice of the urban gardeners for the farming options proceeds the act of production through the conscious manipulation of natural resources, by the means of mobilizing practices (soil improvement, pest control means, watering), as well as supported by knowledge and sustainable viewpoint. Nonetheless, local ecosystem services will support gardener motivation, enhancing knowledge of sustainable gardening, authorizing the rational use of bio-control and soil improvement products, expresses an essential need for rational usage of water and other environmental resources.

In Europe, the demographic profile is towards an increasingly aged workforce [1], characterized by a significant aging of the population. The people aged 55 years or more accounted for one fifth of the total workforce, and as one consequence of increasing longevity, must work more years before retirement [2].Aging of the workforce is a growing problem for many developed and developing countries, pushing companies to explore ways to keep older workers employed for a longer period of time and to support them to maintain their work ability and increase their employability. The literature shows that “age related factors should be taken into consideration in daily management, including work arrangements and individual work tasks, so that everybody, regardless of age, feels empowered in reaching their own and corporate goals” [3].At the same rhythm with these challenges related to the ageing workforce, the work itself is undergoing technological upgrading driven by digitization. ICT (Information and Communication Technologies) have radically determined the modification of people's habits and lifestyles, also in the field of work, introducing new methods of working for example the smart working. These evolving work methods required smart workers to acquire new professional skills in a short time and to adapt to new technologies, new work processes and new forms of collaboration. All these changes lead to greater difficulties, especially for aged smart workers, such as: i) lack of physical interactions and the resulting isolation; ii) increased workload and consequently increased stress (always on); iii) difficulties in communication and time management problems; iv) work-life balance and personal life problems. Therefore it emerges the need to design innovative and friendly devices to address the challenges and difficulties mentioned above, facilitating interaction between smart workers, time management and work organization. These innovative devices and systems need to be easy to use and intuitive to learn in order to increase the inclusion of the aging smart workers, reducing the digital divide.Tangible User Interfaces could represent a fertile ground with the greatest potential to tackle these challenges as they give physical form to digital information and computation, and at the same time they facilitate the direct manipulation of bits. Unlike GUIs, where human-machine interaction occurs through the use of a mouse, keyboard or touchpad and is displayed on a screen as interaction’s results, the use of TUIs involves direct interaction with physical objects to which digital information has been associated, within a defined action space.In this context, the challenge is how ICT-embedded solutions, particularly Tangible User Interfaces, can meet the needs of a growing number of ageing smart worker in terms of inclusion, and of social, physical and mental wellbeing to sustain a team spirit, maintain team cohesion by offering sensory user experience and a tactile interaction with digitized work.The general objective of the research project presented in this article is to develop ICT-embedded devices based on TUIs, aimed at aging smart workers, with following objectives:fostering communication and interaction with the digital world through a tactile experience;increasing the organization, motivation, and job satisfaction; promoting work-life balance to increase physical and mental wellbeing. The result consists of a digital devices’ system, that can interact with each other and with users through a dedicated application for mobile. The system allows to improve the smart workers experience and their well-being through:empowerment, with the introduction of a "digital personal coach" who accompanies the worker during the performance of the activities;enhancement of concentration by providing for the performance of only one activity at a time to increase the overall efficiency of the worker;work-life balance improvement, with a better management of the balance between working and private dimensions;communication and collaboration facilitation with other colleagues;reduction of technological abundance through the use of tangible interfaces;exploitation of peripheral interaction to reduce the risk of loss of concentration during activities.1.European Commission - Directorate-General for Economic and Financial Affairs: The 2015 Ageing Report. Underlying Assumptions and Projection Methodologies. European Economy 8-2014 (2014). 2.Giakoumis, D., Votis, K., Altsitsiadis, E., Segkouli, S., Paliokas, I., & Tzovaras, D.: Smart, personalized and adaptive ICT solutions for active, healthy and productive ageing with enhanced workability. In: 12th ACM International Conference on PErvasive Technologies Related to Assistive Environments, pp. 442-447. Association for Computing Machinery, New York (2019).3.Ilmarinen, J. (2012). Promoting active ageing in the workplace. European Agency for Safety and Health at Work.

- Original objectives and revision: The feasibility study performed in the last year was aimed at determining the symbiotic profiles of eight selected Culicoidesspecies in Israel and the USA by: Comparing bacterial communities among geographic populations of primary bluetongue virus (BTV) vectors. Comparing bacterial communities between adults of field-collected, mammal-feeding BTV vectors and non-vectors. Comparing bacterial communities within and between mammal feeders and bird feeders, with special attention to species with unique immature habitats. We made an effort to collect the eight species during the beginning of the project, however, due to the short available collection season, and the significant changes in habitats available for Israeli Culicoides, we initially determined the symbiotic profile of five species: two BTV vectors (C. sonorensis, C. imicola), one mammal feeders with unknown vectoring ability (C. schultzei), one bird feeder (C. crepuscularis), and one unique habitat species (C. cacticola). In addition, upon preliminary symbiont identification we focused our effort on relevant specific symbionts. Background: Biting midges (Culicoides, Diptera: Ceratopogonidae) are vectors of many major viral diseases affecting farm animals, including BT, which is listed among the most damaging by the World Organization for Animal Health (OIE) and has recently emerged in completely unexpected areas (Northern Europe). One of the strategies to reduce the vectorial capacity of insect vectors is by manipulating their specific symbionts either to affect the vector species or to influence performance of the disease agent within it. Despite significant efforts to elucidate the vectorial capacity of certain Culicoidesspecies, and the critical basis of variability in infection, almost no attention has been given to symbiotic interactions between the vector and its bacterial tenants. It is now established that bacterial symbionts have major influences on their host biology, and may interact with disease agents vectored by their hosts. - Major conclusions, solutions, achievements: During the feasibility project we have found two major bacterial symbionts in Israeli and American Culicoides. In Israel we discovered that C. imicola, a known vector of BT, and C. schultzeigp. a suspected vector of BT, carry the symbiotic bacterium Cardinium, a reproductive manipulator symbiont. In C. imicolathe infection rate was close to 50%, and in C. schultzeiit was lower, and restricted to one of two species within Schultzeigroup. In 3 American species (C. sonorensis, C. crepuscularis, C. cacticola) we found the bacterium Burkholderiasp. In all species tested we have also found other bacterial species in diverse quantities and frequencies. - Implications, both scientific and agricultural: Finding specific symbionts in Culicoidesvector species is the first step in developing symbiont based control (SBC) strategies. Both identified symbionts are known from other insects, and Cardiniumis also known as a reproductive manipulator that can cause cytoplasmic incompatibility, an important phenomenon that can be used for spreading desired traits in infected populations. The role of the symbionts in Culicoideshost can be target for manipulation to reduce the vectorial capacity of the host by either changing its fitness so that it is unable to serve as a vector, or by directly changing the symbiont in a way that will affect the performance of the disease agent in its vector. Since Burkholderiaperhaps can be cultured independently of the host, it is a promising candidate for the later option. Thus, we have now opened the door for studying the specific interactions between symbionts and vector species.

The transition of plants from a juvenile to adult growth phase entails a wide range of changes in growth habit, physiological competence and composition. Strikingly, most of these changes are coordinated by the expression of a single regulator, micro RNA 156 (miR156) that coordinately regulates a family of SBP genes containing a miR156 recognition site in the coding region or in their 3’ UTR. In the framework of this research, we have taken a broad taxonomic approach to examine the role of miR156 and other genetic regulators in phase change transition and its implication to plant development and crop improvement. We set to: Determine the common and unique factors that are altered upon juvenile to adult phase transition. Determine the functions of select miR156 target genes in tomato and maize, and identify those targets that mediate phase transition. Characterize the role of miR172 and its targets in tomato phase change. Determine the relationships between the various molecular circuits directing phase change. Determine the effects of regulated manipulation of phase change genes on plant architecture and if applicable, productivity. In the course of the study, a new technology for gene expression was introduced – next generation sequencing (NGS). Hence some of the original experiments that were planned with other platforms of RNA profiling, primarily Affymetrix arrays, were substituted with the new technology. Yet, not all were fully completed. Moreover, once the initial stage was completed, each group chose to focus its efforts on specific components of the phase change program. The Israeli group focused on the roles of the DELAYED SYMPODIAL TERMINATION and FALSIFLORA factors in tomato age dependent programs whereas the US group characterized in detail the role of miR156 (also termed Cg) in other grasses and in maize, its interplay with the many genes encoding miR172.

The worldwide market for ornamental saltwater invertebrates supplies the needs of millions of aquarium hobbyists, public exhibitions (i.e., zoos) universities and research institutions. With respect to reef building corals, it is estimated that more than half a million coral colonies/year from a total 93 genera, were exported globally during the period of 1985-1997. International value of retail sale of live coral trade alone is estimated as $78 million in 1997 (not including the illegally, widely smuggled material). The continuous, large-scale collection of marine organisms is responsible, in many places, for the destruction of coral reefs. The expected expansion of the trade further threatens these fragile habitats. While no true captive-bred corals are commercially available, our long-term goal is to develop ex situ inland farming of coral colonies that will circumvent the need for in situ collections and will provide domesticated specimens for the trade and for research. We simultaneously studied two model branching coral species, Stylophora pistillata (Pocilloporidae; in Israel) and Porites (Poritidae; in the US). The proposal included three specific aims: (a) To develop protocols for nubbins (small fragments, down to the size of a single polyp) usage in coral farming;(b) To address the significance of colony pattern formation to the coral trade; and (c) To develop the protocols of using nubbins in physiological and ecotoxicological assays (using oil dispersants, the expression of the stress protein HSP-70, household detergents, etc.). Ten scientific publications (published manuscripts, accepted for publications, submitted to scientific journals, in preparation), revealing results that were related to all three specific aims, originated from this BARD proposal. As a result of the work supported by the BARD, we have now, in hand, original and improved protocols for coral maintenance ex situ, proven expertise on manipulating coral colonies’ pattern formation and biological knowledge on island mariculture of reef corals (from Hawaii and from the Red Sea) amenable for the ornamental trade (for public and private aquaria use, for experimentation). At least one Israeli company (Red Sea Corals, Ltd., KibbutzSaar) is using our methodologies for further developing this new mariculture sector. We are now in the process of introducing the rationale and methodologies to Hawaiian private entities to expand dissemination of the research outcomes.

Symbiotic bacteria have been shown to influence host reproduction and defense against biotic and abiotic stressors, and this relates to possible development of a symbiont-based control strategy. This project was based on the hypothesis that symbionts have a significant impact on Culicoides fitness and vector competence for animal viruses. The original objectives in our proposal were: 1. Molecular identification and localization of the newly-discovered symbiotic bacteria within C. imicola and C. schultzei in Israel and C. sonorensis in California. 2. Determination of the prevalence of symbiotic bacteria within different vector Culicoides populations. 3. Documentation of specific symbiont effects on vector reproduction and defense: 3a) test for cytoplasmic incompatibility in Cardinium-infected species; 3b) experimentally evaluate the role of the symbiont on infection or parasitism by key Culicoides natural enemies (iridescent virus and mermithid nematode). 4. Testing the role(s) of the symbionts in possible protection against infection of vector Culicoides by BTV. According to preliminary findings and difficulties in performing experimental procedures performed in other insect symbiosis systems where insect host cultures are easily maintained, we modified the last two objectives as follows: Obj. 3, we tested how symbionts affected general fitness of Israeli Culicoides species, and thoroughly described and evaluated the correlation between American Culicoides and their bacterial communities in the field. We also tried alternative methods to test symbiont-Culicoides interactions and launched studies to characterize low-temperature stress tolerances of the main US vector, which may be related to symbionts. Obj. 4, we tested the correlation between EHDV (instead of BTV) aquisition and Cardinium infection. Culicoides-bornearboviral diseases are emerging or re-emerging worldwide, causing direct and indirect economic losses as well as reduction in animal welfare. One novel strategy to reduce insects’ vectorial capacity is by manipulating specific symbionts to affect vector fitness or performance of the disease agent within. Little was known on the bacterial tenants occupying various Culicoides species, and thus, this project was initiated with the above aims. During this project, we were able to describe the symbiont Cardinium and whole bacterial communities in Israeli and American Culicoides species respectively. We showed that Cardinium infection prevalence is determined by land surface temperature, and this may be important to the larval stage. We also showed no patent significant effect of Cardinium on adult fitness parameters. We showed that the bacterial community in C. sonorensis varies significantly with the host’s developmental stage, but it varies little across multiple wastewater pond environments. This may indicate some specific biological interactions and allowed us to describe a “core microbiome” for C. sonorensis. The final set of analyses that include habitat sample is currently done, in order to separate the more intimately-associated bacteria from those inhabiting the gut contents or cuticle surface (which also could be important). We were also able to carefully study other biological aspects of Culicoides and were able to discriminate two species in C. schultzei group in Israel, and to investigate low temperature tolerances of C. sonorensis that may be related to symbionts. Scientific implications include the establishment of bacterial identification and interactions in Culicoides (our work is cited in other bacteria-Culicoides studies), the development molecular identification of C. schultzei group, and the detailed description of the microbiome of the immature and matched adult stages of C. sonorensis. Agricultural implications include understanding of intrinsic factors that govern Culicoides biology and population regulation, which may be relevant for vector control or reduction in pathogen transmission. Being able to precisely identify Culicoides species is central to understanding Culicoides borne disease epidemiology.