Global ETD Search

11	Effects of Habitat Change on Bird Species Richness in Ontario, Canada De Camargo, Rafael Xavier January 2013 (has links) It is generally assumed that when natural habitat is converted to human-dominated cover such area is “lost” to its native species. Extinctions will ensue. The literature generally assumes that species are extirpated as natural area is reduced, following the well-known species-area relationship (SAR). However, SARs have consistently over-estimated species losses resulting from conversion of natural habitat to human-dominated land covers. We hypothesize that the overestimation occurs because these area-based models assume that converted habitat is “lost”, eliminating all species. However, in the real world, conversion of natural land cover to human-dominated cover frequently produces new land covers, different from the original habitat, but not necessarily completely inhospitable to biodiversity. We evaluated the responses of total avian richness, forest bird richness and open habitat bird richness to remaining natural area within 991 quadrats, each 100 km2, across southern Ontario. Total bird species richness does not follow SAR predictions; rather, the number of bird species peaks at roughly 50% natural land cover. The richness of forest birds does follow the usual SAR power-law as a function of forested area. In contrast, richness of birds that prefer open-habitat does not increase monotonically with either natural- or human-dominated land cover. However, we can partition human-dominated land cover into an “available human-dominated” component and “lost” habitat. Richness of open-habitat species relates to the amount of available human-dominated cover. Distinguishing three habitat types (natural, available human-dominated, and lost) permits accurate predictions of species losses in response to natural habitat conversion. bird species richness Endemic-area relationship southern Ontario Species-area relationship
12	Relationships among the species occupancy of marsh birds and vegetation in a wetland ecosystem: a statistics and GIS practicum with the Ottawa National Wildlife Refuge, Lake Erie Credico, Jeena 22 January 2015 (has links) No description available. Environmental Science marsh bird species wetland habitat species occupancy vegetation cover
13	Distribution, territorial limitations, and patch colonization dynamics of bird species in a fragmented temperate-zone woodland landscape Groom, Jeremiah D. 14 October 2003 (has links) No description available. Biology, Ecology Fragmentation riparian woodland bird species habitat area gap-crossing metapopulation colonization
14	Právní úprava ochrany volně žijících druhů ptáků / Legal regulation of protection of wild bird species Kubešová, Jana January 2021 (has links) Legal regulation of protection of wild bird species Abstract This thesis deals with legal regulation of protection of wild bird species at the international, European and Czech level. The aim of the thesis was to provide an overview of legal regulation of protection of wild bird species, and to evaluate whether this legal regulation is an effective means of achieving objectives which led to its adoption. The thesis consists of an introduction, three main parts and a conclusion. The first part of the thesis describes protection of birds in international law. In this part of the thesis there are first introduced international organizations important for protection of birds, in particular International Union for Conservation of Nature and BirdLife International, and then in the author's opinion the most relevant international conventions to protection of birds, namely the Ramsar Convention, the Bonn Convention, the Bern Convention and the Convention on Biological Diversity. The following second part of the thesis focuses on protection of birds in European law. In this part of the thesis legal regulation of protection of wild bird species in Directive 2009/147/EC (the Birds Directive) is described in detail including the related case law of Court of Justice of the European Union. The author pays attention...
15	Vývoj početnosti lesních ptáků v České republice / Population trends of forest birds in Czechia Szarvas, Filip January 2021 (has links) Currently, most scientific attention focused on bird population trends is centred on birds in the agricultural landscape. Forest bird research, on the other hand, is given far less space, despite the fact that forests in Europe often form a substantial part of the landscape in some parts. Moreover, it is undergoing drastic changes throughout Europe, and especially in the Czech Republic. In the second half of the 20th century, their quality deteriorated due to air pollution, later regenerated, but other additional challenges have emerged, such as global climate change and epidemics of wood-destroying insects. It is therefore possible to assume their fundamental influence on forest bird populations. However, most of the work examining the effects of the forest environment and forest management on bird populations is only very local, limited to ecologically valuable, and therefore quite specific, habitats, or covering only a small number of bird species. However, data on the evolution of forest birds vary across Europe. In Finland, for example, forest birds are declining, while in neighbouring Sweden the trend is the opposite. In this study, I aim to better map what characteristics of forests affect specific species of birds, in research conducted throughout the Czech Republic. I decided to explore...
16	Conservation Banks : Analyzing the Commodification of Nature and the Effects on Biodiversity in the U.S. Sindre, Josef January 2024 (has links) In this thesis, the impact of conservation banking on biodiversity is assessed by examining the bird species richness in U.S. counties that have implemented the policy. Conservation banking is a market-based instrument designed for developers who need to comply with the Endangered Species Act for the negative environmental impacts that their projects have made. Conservation banking aims to “protect and recover imperilled species and the ecosystems upon which they depend” (USFWS 2013, p. 1). In this thesis, a staggered difference-in-difference with differential timing by Goodman-Bacon (2018) and further developed by Callaway and Sant’Anna (2021) is used to estimate the effect of conservation banks on biodiversity. Data for biodiversity, bird species richness are collected from U.S. Geological Survey's data from the North American Breeding Bird Survey (BBS). Information on conservation banks is gathered from the Regulatory In-lieu fee and Bank Information Tracking System (RIBITS). This thesis focuses on 107 conservation banks in 53 counties in the U.S. established between 2005 and 2016. The main results from this study indicate a positive impact of the introduction of conservation banks, with an increase in biodiversity of 4,1%. Consequently, this confirms the positive effect of the policy intervention. Despite these results, it is vital to consider caution regarding this market-based instrument. Market-based instruments that commodify elements of nature into the market are a new frontier in capitalist expansion. This approach may exclude areas from the natural evolutionary selection process, leading to potential long-term ecological imbalances. Current payment structures in conservation banking can lead to misallocation of taxpayers’ money at the same time as biodiversity outcomes are not optimized. Therefore, the most fundamental recommendation for this policy is to change to outcome-based payments. Conservation Banking Market-Based Instruments Biodiversity Offsets Bird species richness Economics Nationalekonomi
17	Studies of the Bird Life of Denton County, Texas Rylander, Michael Kent 01 1900 (has links) "As a means of defining the purpose of the problem, the following objectives were considered: (1) to list the species of birds observed in Denton and neighboring counties; (2) to assign a descriptive status to each species; (3) to estimate the relative abundance of each species (4) to annotate the list with data from other sources, when additional data provide a more accurate and complete description of the status of the species in Denton County; (5) to designate the section of the county in which each species was most frequently observed; and (6) to briefly summarize the changes in bird populations during the period 1950-1956, and to suggest some hypotheses which help explain these changes." -- leaf 6. ornithology Denton County, Texas East Texas Ornithology Club bird species discriptions Birds -- Texas -- Denton County. Denton County (Tex.) -- History.
18	Establishing conservation management for avian threatened species Ponnikas, S. (Suvi) 18 February 2014 (has links) Abstract The protection of endangered species requires knowledge about the habitat requirements and the genetic issues related to the population viability. In this doctoral thesis, I defined the breeding habitat features of the Finnish populations of the Golden Eagle (Aquila chrysaetos) and the Peregrine Falcon (Falco peregrinus) by applying habitat suitability modelling. Secondly, I studied the conservation genetic issues of the Finnish population of the White-tailed Eagle (Haliaeetus albicilla) and the two Reed Bunting subspecies Emberiza schoeniclus witherbyi and E.s. lusitanica met in the Iberian Peninsula. All study populations are classified as threatened according to IUCN classification and they have experienced declines in population sizes in recent history. My results from habitat suitability models showed that human-induced changes in habitat threaten the Golden Eagle in Finland. The relative suitability for the species presence dropped to zero when the proportion of human altered landscape (agricultural or urbanized areas) in the core of the breeding habitat (4 km2) was more than 5%. Models further showed that habitat structure influences breeding habitat selection of the Peregrine Falcon, as it favours well-connected areas of open peatlands. Therefore, fragmentation (i.e., decreasing the connectivity) of open peatlands decreases the habitat quality for the species. The White-tailed Eagle has recovered mainly through local growth, but my results suggest that gene flow from neighbouring populations has had an impact as well, and has enhanced the genetic viability of the Finnish population. The current structure of the two subpopulations (one along the Baltic Sea coast line and another inland in Northern Finland) results mainly from the species’ ecology (i.e., philopatric behaviour), not from the recent population bottlenecks. The effective population size estimate of the coastal subpopulation of White-tailed Eagle was below the critical size needed to maintain evolutionary potential. The estimates of the effective population sizes for E.s. lusitanica and E.s. witherbyi and inland subpopulation of White-tailed Eagle were close or below the critical level of 50, which makes them prone to losing fitness due to inbreeding depression in the short term. Therefore, these study populations need to increase in size in order to secure population viability in the future. / Tiivistelmä Ihmisen aiheuttamat elinympäristöjen muutokset uhkaavat biodiversiteettiä kasvattamalla yhä useampien eliölajien sukupuuttoriskiä. Tehokkaat suojelutoimenpiteet edellyttävät tietoa uhanalaisten lajien elinympäristövaatimuksista sekä populaation elinkyvylle keskeisistä geneettisistä tekijöistä. Tarkastelen väitöskirjatyössäni maakotkan (Aquila chrysaetos) sekä muuttohaukan (Falco peregrinus) Suomen populaatioiden pesimäympäristön piirteitä maisemaekologisen mallinnuksen avulla. Toiseksi tarkastelen Suomen merikotkapopulaation (Haliaeetus albicilla) sekä Iberian niemimaalla esiintyvien pajusirkun alalajien Emberiza schoeniclus witherbyin ja E.s. lusitanican suojelun kannalta tärkeitä geneettisiä tekijöitä. Kaikki tutkimuspopulaatiot ovat uhanalaisia ja ne ovat kärsineet voimakkaista kannan pienenemisistä. Maisemaekologiset mallit osoittivat maakotkan välttävän ihmisen muokkaamaa ympäristöä (maatalousalueet ja rakennetut alueet). Lajin esiintymistodennäköisyys laski nopeasti nollaan, kun ihmisen muokkaaman ympäristön osuus nousi yli 5 prosenttiin pesimäympäristön ydinalueella (4 km2). Mallit osoittivat maiseman rakenteen vaikuttavan muuttohaukan habitaatinvalintaan, sillä se suosi pesimäympäristönään kytkeytyneitä avosoita. Avosoiden pirstoutuminen (l. kytkeytyneisyyden väheneminen) vähentää näin ollen muuttohaukan pesimäympäristön laatua. Merikotkapopulaatio on toipunut pääosin paikallisen kasvun myötä, mutta tulokseni viittaavat myös siihen, että geenivirta naapurimaiden populaatioista on lisännyt Suomen populaation geneettistä muuntelua. Nykyinen rakenne (rannikon ja Lapin alapopulaatiot) on seurausta lajin synnyinpaikkauskollisuudesta, ei niinkään populaatiokoon romahduksista. Rannikon merikotkapopulaation efektiivinen koko jäi alle kriittisen rajan, joka tarvitaan evolutiivisen potentiaalin säilymiselle. Pajusirkun alalajien sekä Lapin merikotkapopulaation efektiiviset populaatiokoot olivat lähellä kriittisenä pidettyä 50:tä tai jäivät alle, joten ne ovat vaarassa menettää kelpoisuutta sukusiitosdepression seurauksena lyhyellä aikavälillä. Sekä pajusirkun alalajien että merikotkapopulaatioiden tulee sen vuoksi kasvaa säilyäkseen elinvoimaisina tulevaisuudessa. conservation genetics endangered bird species habitat suitability modelling luonnonsuojelugenetiikka maisemaekologinen mallinnus uhanalaiset lintulajit Aquila chrysaetos Emberiza schoeniclus lusitanica Emberiza schoeniclus witherbyi Falco peregrinus Haliaeetus albicilla
19	Birds, bats and arthropods in tropical agroforestry landscapes: Functional diversity, multitrophic interactions and crop yield Maas, Bea 20 November 2013 (has links) No description available. 630 birds bats arthropods multitrophic interactions agroforestry tropical landscape forest margin landscape functional diversity crop yield exclosure experiments experimental exclusion arthropod suppression avian predation ecosystem services mist netting point counts artificial plasticine caterpillar dummy experiment biological control monitoring mapping Lemon-bellied White-eye Grosbeak Starling Zosterops chloris Scissiostrum dubium Theobroma cacao cacao agroforestry cacao diseases cacao harvest cacao pests flying vertebrates aerial insectivores volant vertebrates logging breeding colony flower herbivory mesopredator release predatory insects ants spiders aphids Lepidoptera Coleoptera Lepidopteran larvae sustainable agriculture sustainable agroforestry management implications management recommendations applied managament extensive land use management landscape management conservation biodiversity-friendly dbh distance to forest forest proximity habitat conversion herbivory Indonesia insectivorous bats insectivorous birds invertebrates Central Sulawesi Napu valley leaf gleaning leaf herbivory pests insects phytophagous insects plant productivity remnant forest trees shade tree managament South-east Asia Paleotropics tropical landscape tree height landscape gradient local shade management Cacao Pod Borer Cherelle Wilt fruit abortion Helopeltis sulawesi deforestation habitat fragmentation land use intensification forest margin species critical decline predation experiment species-specific functions Southeast Asia biodiversity conservation mesopredators food security human welfare human well-being poverty alleviation poverty reduction smallholder cacao smallholder plantation cacao farmers sustainable cacao management landscape perspective landscape scale large scale field experiment long term field experiment human wellbeing economic importance economic value valuation ecosystem services landscape matrix yield quality yield quantity fruit productivity species identity species diversity species richness ecosystem functioning pesticide use chemical compounds complex food web tritrophic interactions wildlife-friendly rural livelihoods endangered bird species endangered bat species endemic endemic birds endemic bats beneficial impact IUCN Lore Lindu National Park bioindicator indicator species forest margin agricultural habitat agroforestry systems population density predation activity species activity cacao flower cacao pod Orthoptera linear mixed effect models Tukey Post Hoc Test AICc model selection generalized least squares restricted maximum likelihood model simplification species richness estimator species accumulation linear mixed-effects models Likelihood Ratio Test Maximum Likelihood nocturnal insects diurnal arthropods nocturnal arthropods diurnal insects landscape context Land- und Forstwirtschaft (PPN621302791)

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