Trends in Rio Grande wild turkey (Meleagris gallopavo intermedia) abundance on the Edwards Plateau (EP), Texas, have been either stable or in decline since the 1970s. Four study areas, 2 each within stable (Stable Area A, SAA; Stable Area B, SAB) and declining regions (Declining Area A, DAA; Declining Area B, DAB), were delineated to examine (1) both annual and seasonal survival, (2) relative mammalian predator mean abundance (RMA), and (3) potential effects of lunar phase on scent-station visitation. During February 2001-March 2003, 257 turkeys were captured and instrumented with radio transmitters. Survival probabilities were generated using a Kaplan-Meier product limit estimator; a log-rank test tested for differences among sites. Annual survival was statistically different between regions (stable 0.566 ± 0.081; declining 0.737 ± 0.094; X2 = 3.68, P = 0.055) in 2002. Seasonal survival differed between regions (stable 0.812 ± 0.103; declining 0.718 ± 0.130; X2 = 3.88, P = 0.049) in spring 2003. Annual survival results during 2002 were counterintuitive with turkey trend data. Scent-station transects were established on non-paved ranch roads within study regions. Scent-station indices revealed higher (H = 19.653, P ≤ 0.001) RMA of opossum (Didelphis virginiana) and skunk (eastern spotted [Spilogale putorius], striped [Mephitis mephitis], or western spotted [S. gracilis]) (SAA, x⎯ = 0.0148; SAB, x⎯ = 0.0151; DAA, x⎯ = 0.0042; DAB, x⎯ = 0.0065) on stable areas. Higher RMA of coyotes (Canis latrans) on declining areas (SAA, x⎯ = 0.0067; SAB, x⎯ = 0.0022; DAA x⎯ = 0.0234; DAB x⎯ = 0.0434) suggested a possible causative factor of the decline, but abundance indices were not verified by empirical data though. Lunar phase was not a significant (T = -0.225, P = 0.822) covariate in scent-station visits by raccoons, opossums (new, x⎯ = 0.0111; full, x⎯ = 0.0324), or unidentified tracks (new, x⎯ = 0.0649; full, x⎯ = 0.0375). Nightly precipitation and wind speed probably influence mammalian use of scent stations more so than lunar illumination.

To make reference to Trakai district`s variety of predators mammals and the spread of the researches, literature, hunters, foresters, and environment agency workers data, there are existing 13 of predator mammals.

The assumption that the colours of the green poison frog, Dendrobates auratus, serve as a warning of unpalatability is not supported because the requirements of the theory of aposematism are not met. The theory predicts that the aposematic coloration be conspicuous to potential predators, yet this cannot be demonstrated. The only predator found for D. auratus was the theraphosid spider, Sericopelma rubronitens, which hunts using vibrational cues. Only after sampling all frogs offered did spiders reject the toxic D. auratus over nontoxic Physalaemus pustulosus. The spider's decision to reject D. auratus as prey was made without visual input, and therefore the colours and toxicity of the frogs are decoupled with respect to this predator. Discovering that the crab Armases angustum is a predator of D. auratus tadpoles suggests that D. auratus is most vulnerable to predation during the nontoxic tadpole stage. Indirect methods of estimating predation were unsuccessful. The use of plasticine model frogs to estimate avian predation yielded no useful information and although traumatic injury is usually attributed to attempted predation, this is not true for tropical anurans. The levels of traumatic injury for D. auratus and a cryptic nontoxic frog Physalaemus pustulosus were similar when the life span of the frogs was taken into account. The traumatic injuries in these frogs are a function of interactions with small invertebrates that are neither predator nor prey. The theory of aposematism also predicts that there should be low pattern variation within an aposematic species so that a single search image can be formed and avoided. The patterns of D. auratus are individually distinct and there is significant interpopulational variation in appearance due to differences in colour, pattern and animal size. Selection for conspicuous visual intraspecific communication may have resulted in these differences in appearance. Mitochondrial 16S rRNA and cytochrome b sequence data ind

The sardine run is a spectacular but poorly understood natural phenomenon. This research aims to broaden scientific knowledge pertaining to sardine, Sardinops sagax, distribution, both in relation to their predators and environmental conditions. Sardine distribution was closely related to sea temperature. Sardines were sighted every year along the Lower Wild Coast, where continental shelf conditions were cooled by the Port Alfred upwelling cell. To the north of Mbashe River, shelf conditions were dominated by the warm Agulhas Current, and sardine distribution varied annually in close relation with sea temperature conditions. Along this coastline sardine abundance always peaked between Waterfall Bluff and Port St Johns with favourable conditions caused by the westward inflection of the coastline and the shelf bathymetry. Topographically-induced upwelling was concluded to be the cause of cooler sea temperatures and elevated chl a concentrations. Although chl a concentration appeared to be associated with east coast sardine distribution, the uncertainty with regards data accuracy hindered their usefulness as a predictor of suitable biological conditions for sardine. Sardine northward movement along the KZN coastline was impeded adjacent to the Durban Eddy, where they were forced shorewards by the warm conditions. This coincided with the peak in beach seine catches. The Cape Gannet, Morus capensis, was very closely associated with sardine along the entire east coast. Their abundance declined substantially adjacent to the Durban Eddy. Prevailing atmospheric conditions affected gannet behaviour: they travelled more frequently during strong alongshore winds and foraged more upon cessation of such winds. Gannets were closely associated with feeding dolphins at both coarse and fine scales, and responded to changes in dolphin behaviour. Common dolphin, Delphinus capensis, abundance and group size peaked between Waterfall Bluff and Port St Johns. Along this stretch of coastline they travelled more slowly, and in pods more perpendicular to the bathymetry of the region. Bottlenose dolphin, Tursiops aduncus, abundance increased during the sardine run with the influx of a migrant stock which reached the KZN Mid South Coast. Humpback Whale, Megaptera novaeangliae, and sardine distributions did not appear to be related. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2009.

Poison hemlock, Conium maculatum (Apiaceae), is an invasive plant in North America with a unique toxic chemistry. Previous research on this plant has focused on identifying herbivores as potential biological control agents or describing the toxic plant alkaloids. However, none have examined the role of higher trophic levels in the food web surrounding poison hemlock. Generalist predators and food web interactions are an important component of studies investigating invasion effects, as plant or animal introductions can alter ecosystem functioning. In this study, predators in poison hemlock were sampled at the foliar and epigeal levels, resulting in 956 Carabidae and 321 Coccinellidae being collected. Predator connectedness to plant resources was quantified using molecular gut-content and chemical analyses. Foliar Harmonia axyridis (Coccinellidae) contained aphid DNA and plant chemicals, while Harpalus pensylvanicus (Carabidae) only contained alkaloids, suggesting that the ground predators were obtaining plant chemicals via alternative prey. Feeding trials between H. axyridis and their potentially toxic prey, Hyadaphis foeniculi (Aphididae), revealed that the exotic predator shows faster development when consuming aphids from poison hemlock compared to alternative diets. This study reveals that three Eurasian species may be facilitating one another, illustrating the importance of continued examination of invasive species interactions.

No description available.

Little research has been conducted in the Republic of Panama concerning mammalian predator and prey populations. New Technologies such as remote camera-traps, allow researcher to efficiently monitor elusive wildlife species within dense tropical vegetation. The general goal of this study was to establish concrete evidence of the felid population in EcoParque Panama-a newly designated protected area adjacent to Panama City. The specific objective of the study was to estimate the relative abundance of predators and prey species in order to determine the feasibility of releasing more felids into the area that were to be removed from the Panama Canal Expansion Zone. Camera-traps were purposefully located in likely felid habitat and data were collected for approximately 5 months. Photographs were analyzed according to species and location captured, and abundances were established. Using SPSS and Statistix statistical software, tests for association between likely habitat for felids and time activity periods for prey species were conducted. EcoParque was found to have a robust prey population with relatively few predators. Felid predators present include the ocelot (Leopardus pardalis) and jaguarundi (Felis yaguarondi). Results suggest that felid carrying capacity has not been reached and additional individuals could be released into the area. This preliminary study lays the ground work for further research in EcoParque as well as the rest of Panama concerning predator and prey species relationships.

Submitted by MAIARA ALEXANDRE CRUZ (maiara_agronomia@hotmail.com) on 2018-04-16T14:10:46Z No. of bitstreams: 2 Dissertaçao_Maiara_Alexandre_Cruz.pdf: 2216345 bytes, checksum: c797b70103395ccc0e6fb5cc74a155ef (MD5) DISSERTAÇÃO COMPLETA repositorio.docx: 2205488 bytes, checksum: 87334bbb24da1f49c2f7403a20b4b5ea (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-04-16T18:24:58Z (GMT) No. of bitstreams: 1 cruz_ma_me_jabo.pdf: 2216345 bytes, checksum: c797b70103395ccc0e6fb5cc74a155ef (MD5) / Made available in DSpace on 2018-04-16T18:24:58Z (GMT). No. of bitstreams: 1 cruz_ma_me_jabo.pdf: 2216345 bytes, checksum: c797b70103395ccc0e6fb5cc74a155ef (MD5) Previous issue date: 2018-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / RESUMO – A agricultura é de suma importância para o desenvolvimento do Brasil. O estado de São Paulo, com significativa produção e produtividade de diversas culturas, é o maior produtor de cana-de-açúcar e citros, e o terceiro em café. No entanto, grandes perdas econômicas e ambientais ocorrem pelo uso indiscriminado de agrotóxicos para controlar insetos-praga, incluindo cochonilhas. Informações sobre insetos benéficos atualmente presentes nas regiões produtoras são fundamentais para o manejo integrado de pragas. Este estudo teve como objetivo fazer um levantamento de inimigos naturais associados a espécies de cochonilhas consideradas pragas, primárias ou secundárias, para as culturas de cana-de-açúcar, citros e café no estado de São Paulo, relacionando à origem de cada espécie; especificidade a presa; e as possíveis adaptações a predação ou parasitismo em relação às características morfológicas macroscópicas das cochonilhas. O levantamento de inimigos naturais associados com dez espécies de cocóideos frequentemente associados a estas plantas foi realizado em 15 municípios, situados nas mesorregiões de São José do Rio Preto, Ribeirão Preto, Araraquara e Campinas. As coletas foram realizadas entre agosto de 2016 e agosto de 2017, de maneira aleatória, em áreas urbana e rural. Nesse período, foram coletadas 52 espécies de inimigos naturais. Para cochonilhas da cana-de-açúcar, todas as associações são novos relatos para o estado de São Paulo; e, Anagyrus saccharicola Timberlake, 1932 e Mariola flava Noyes, 1980 (Hymenoptera: Encyrtidae) sâo registrados pela primeira vez para o para o país. Entre as cochonilhas que frequentemente infestam citros e café, e seus respectivos inimigos nturais. 21 novas associações foram registradas. Dentre os predadores obtidos, Pseudoazya nana (Marshall, 1912) (Coleoptera: Coccinelidae), e, os parasitoides Arrhenophagus chionaspidis Aurivillius, 1888, Coccidoxenoides perminutus Girault, 1915 (Hymenoptera: Encyrtidae), Coccophagus basalis Compere, 1939 (Hymenoptera: Aphelinidae), são registrados pela primeira vez para o estado de São Paulo. Para o Brasil são registrados: Coccophagus flavifrons Howard, 1885 e Coccophagus rusti Compere, 1928 ((Hymenoptera: Aphelinidae). / ABSTRAT– Agriculture is of great importance for the development of Brazil. The state of São Paulo, with significant production and productivity of several crops, is the largest producer of sugarcane and citrus, and the third in coffee. However, major economic and environmental losses occur through the indiscriminate use of pesticides to control pest insects, including scale insects. Information on beneficial insects currently present in producing regions is essential for integrated pest management. The objective of this study was to survey natural enemies associated with scale insects species considered as primary or secondary pests for sugarcane, citrus and coffee crops in the state of São Paulo, relating to the origin of each species; specificity prey; and the possible adaptations to predation or parasitism in relation to the macroscopic morphological characteristics of scale insects. The survey of natural enemies associated with ten coccoid species frequently associated with these plantations was carried out in 15 municipalities located in the mesoregions of São José do Rio Preto, Ribeirão Preto, Araraquara and Campinas, in the main sugarcane producing regions, citrus and state coffee. The collections were carried out between August 2016 and August 2017, in a random manner, in urban and rural areas. During this period, 52 species of natural enemies were collected. For sugarcane scale insects, all associations are new reports for the state of São Paulo; and, Anagyrus saccharicola Timberlake, 1932 and Mariola flava Noyes, 1980 (Hymenoptera: Encyrtidae) are recorded for the first time to the country. Among the scale insects that frequently infest citrus and coffee, and their respective nemes. 21 new associations were registered. Among the predators obtained, Pseudoazya nana (Marshall, 1912) (Coleoptera: Coccinelidae), and the parasitoids Arrhenophagus chionaspidis Aurivillius, 1888, Coccidoxenoides perminutus Girault, 1915 (Hymenoptera: Encyrtidae), Coccophagus basalis Compere, 1939 (Hymenoptera: Aphelinidae), are registered for the first time to the state of São Paulo. For Brazil are recorded: Coccophagus flavifrons Howard, 1885 and Coccophagus rusti Compere, 1928 ((Hymenoptera: Aphelinidae).

No description available.

Marine ecosystems contain both highly abundant and diverse communities of vertebrates and invertebrates; however anthropogenic activity has drastically altered the species composition and diversity of these ecosystems. Specifically, human activity has targeted high trophic level species and degraded much of the biogenic habitat that faunal communities rely upon. These alterations have resulted in the loss of many marine predators and overall declines of marine biodiversity. To investigate the consequences of marine predator loss and community level species decline, I use a combination of large-scale data synthesis and in situ field observations of marine fish communities. I first use a meta-analysis approach to synthesize the consequences of marine predator loss in benthic marine ecosystems worldwide. From this synthesis, I was able to determine some of the biotic and abiotic factors that regulate the response of marine herbivores and primary producers to predator loss. Specifically, I show that marine predators have the strongest effect on populations of marine herbivores when predators and herbivores were similar in size and when larger herbivores were involved. Conversely the factors that best explained the response of the primary producer populations were related to the abiotic environment. The results show that primary producers respond the most positively to the presence of predators in high nutrient environments. While I found no link between the magnitude of change in the herbivore population and the magnitude of change in the producer population, I was able to demonstrate that primary producers are under the strongest top-down controls when nutrient concentrations are high, sea surface temperatures are low, and when the predator is larger in size than the herbivore. Finally, I use the data related to marine reserves to show that reserves are an effective tool to help reverse the trophic consequences of marine predator loss and that they are most effective when they are older in age. The third chapter examines the links between community diversity and community biomass within fish communities in eelgrass ecosystems in Northern British Columbia. After controlling for environmental variation, I found that it was the dominance of certain species within a community that resulted in the highest ecosystem function. This finding was demonstrated by both the taxonomic and functional metrics of diversity used. While previous work on this topic has shown that richness is positively correlated to function, my results are to the contrary, and suggest that further investigation into which aspects of community diversity drive ecosystem function is required. In conclusion, my results provide a new synthesis of the consequences of marine predator loss across the world and show how species diversity is linked to ecosystem function in local eelgrass fish communities. / Graduate / 2018-12-17