Master's Theses Directories

Master's Theses Directories
Author:
Publisher:
Total Pages: 312
Release: 2007
Genre: Dissertations, Academic
ISBN:

"Education, arts and social sciences, natural and technical sciences in the United States and Canada".

Oviposition Site Selection by Mosquitoes

Oviposition Site Selection by Mosquitoes
Author: Lauren L.- Eveland
Publisher:
Total Pages: 37
Release:
Genre:
ISBN:

Oviposition site selection is a critical reproductive behavior for egg-laying organisms that offer little to no parental care. Determining the mechanisms females use to assess sites is critical to understanding life history traits, community structure, and species interactions. Mosquitoes are excellent model organisms for studying oviposition site selection for numerous reasons: 1) a poor decision can lead to zero reproductive success, 2) females actively assess and choose among habitat patches when locating an oviposition site, 3) larvae remain in the habitat where they hatch until they metamorphose, and 4) they lay conspicuous egg rafts that allow direct assessment of oviposition. Certain mosquito species actively detect and avoid habitats with predaceous backswimmers (Heteroptera: Notonectidae), and certain species of fish, including Gambusia affinis. For my thesis I focused on mosquitoes of the genus Culex, and how they responded solely to the presence of kairomones (chemicals emitted by an organism and detected by an individual of another species; where only the receiver benefits from the cue) released by Gambusia affinis (Western mosquitofish), Lepomis cyanellus (green sunfish), and Procambarus hayi (straightedge crayfish) when locating oviposition sites. Three paired experiments (Control vs. Predator-conditioned water) were conducted, one for each predator species. A fourth experiment was conducted to determine where Culex would oviposit in the presence of positive, negative, and neutral stimuli. Oviposition choice was quantified by collecting all egg rafts laid in experimental pools. Egg rafts were hatched, raised, and identified to species. In experiment one, Culex restuans used kairomones to detect and avoid ovipositing in the presence of G. affinis. In experiment two, L. cyanellus kairomones did not deter Culex species. In experiment three, mosquitoes were attracted to pools with crayfish-conditioned water over Controls. In experiment four, presence of G. affinis within a pair reduced the number of egg rafts found in Control and Crayfish pools. When not paired with G. affinis, Control and Crayfish pools received significantly more egg rafts than G. affinis pools. Overall, kairomones alone can drive oviposition site choice in Culex restuans, and Culex perceive quality habitats as low quality when in close proximity to G. affinis pools.

Beetles of Eastern North America

Beetles of Eastern North America
Author: Arthur V. Evans
Publisher: Princeton University Press
Total Pages: 566
Release: 2014-06-08
Genre: Nature
ISBN: 1400851823

The most comprehensive full-color guide to the beetles of eastern North America Beetles of Eastern North America is a landmark book—the most comprehensive full-color guide to the remarkably diverse and beautiful beetles of the United States and Canada east of the Mississippi River. It is the first color-illustrated guide to cover 1,406 species in all 115 families that occur in the region—and the first new in-depth guide to the region in more than forty years. Lavishly illustrated with over 1,500 stunning color images by some of the best insect photographers in North America, the book features an engaging and authoritative text by noted beetle expert Arthur Evans. Extensive introductory sections provide essential information on beetle anatomy, reproduction, development, natural history, behavior, and conservation. Also included are tips on where and when to find beetles; how to photograph, collect, and rear beetles; and how to contribute to research. Each family and species account presents concise and easy-to-understand information on identification, natural history, collecting, and geographic range. Organized by family, the book also includes an illustrated key to the most common beetle families, with 31 drawings that aid identification, and features current information on distribution, biology, and taxonomy not found in other guides. An unmatched guide to the rich variety of eastern North American beetles, this is an essential book for amateur naturalists, nature photographers, insect enthusiasts, students, and professional entomologists and other biologists. Provides the only comprehensive, authoritative, and accessible full-color treatment of the region's beetles Covers 1,406 species in all 115 families east of the Mississippi River Features more than 1,500 stunning color images from top photographers Presents concise information on identification, natural history, collecting, and geographic range for each species and family Includes an illustrated key to the most common beetle families

Chemical Ecology in Aquatic Systems

Chemical Ecology in Aquatic Systems
Author: Christer Brönmark
Publisher:
Total Pages: 318
Release: 2012-03
Genre: Nature
ISBN: 0199583102

However, our knowledge of this "chemical network" is still negligible.

A Handbook of Global Freshwater Invasive Species

A Handbook of Global Freshwater Invasive Species
Author: Robert A. Francis
Publisher: Routledge
Total Pages: 456
Release: 2017-08-11
Genre:
ISBN: 9780815378716

Invasive non-native species are a major threat to global biodiversity. Often introduced accidentally through international travel or trade, they invade and colonize new habitats, often with devastating consequences for the local flora and fauna. Their environmental impacts can range from damage to resource production (e.g. agriculture and forestry) and infrastructure (e.g. buildings, road and water supply), to human health. They consequently can have major economic impacts. It is a priority to prevent their introduction and spread, as well as to control them. Freshwater ecosystems are particularly at risk from invasions and are landscape corridors that facilitate the spread of invasives. This book reviews the current state of knowledge of the most notable global invasive freshwater species or groups, based on their severity of economic impact, geographic distribution outside of their native range, extent of research, and recognition of the ecological severity of the impact of the species by the IUCN. As well as some of the very well-known species, the book also covers some invasives that are emerging as serious threats. Examples covered include a range of aquatic and riparian plants, insects, molluscs, crustacea, fish, amphibians, reptiles and mammals, as well as some major pathogens of aquatic organisms. The book also includes overview chapters synthesizing the ecological impact of invasive species in fresh water and summarizing practical implications for the management of rivers and other freshwater habitats.