Ecology and Evolutionary Biology Commons^™

The Rattle Call: A Female-Specific Vocalization In Steller's Jays, Kachina L. Rowland

Cal Poly Humboldt theses and projects

While the elaborate songs of male passerines are well documented for their role in intrasexual resource competition and mate attraction, vocalizations used in female competition are poorly understood. Research has suggested that the female-specific rattle call of Steller’s jays (Cyanocitta stelleri) is used in competition for access to a territory and mate. I describe structural properties of the rattle call, and compare life history traits of individual females to rattle call occurrence. I used two rates to quantify rattle call occurrence from 20 females: rattles per observation period (RPO), and proportion of observations with a rattle call (POR) …

Habitat Segregation Between Brown Bears And Gray Wolves In A Human-Dominated Landscape, Cyril Milleret, Andrés Ordiz, Guillaume Chapron, Harry Peter Andreassen, Jonas Kindberg, Johan Månsson, Aimee Tallian, Petter Wabakken, Camilla Wikenros, Barbara Zimmermann, Jon E. Swenson, Håkan Sand

Ecology Center Publications

Identifying how sympatric species belonging to the same guild coexist is a major question of community ecology and conservation. Habitat segregation between two species might help reduce the effects of interspecific competition and apex predators are of special interest in this context, because their interactions can have consequences for lower trophic levels. However, habitat segregation between sympatric large carnivores has seldom been studied. Based on monitoring of 53 brown bears (Ursus arctos) and seven sympatric adult gray wolves (Canis lupus) equipped with GPS collars in Sweden, we analyzed the degree of interspecific segregation in habitat selection …

Trophic And Competitive Interactions Among Egg Parasitoids Of Stink Bugs, Joanna K. Konopka

Electronic Thesis and Dissertation Repository

The intra- and inter-trophic interactions in ecosystems can be disrupted by invasive species, with lasting effects on population dynamics of native organisms. An invasive species may be attractive as a prey or host to native species, but if unsuitable for consumption or for development of the natural enemy’s progeny, it constitutes an ‘evolutionary trap’. A possibility of such a trap for native egg parasitoids (Hymenoptera: Scelionidae) exists with the introduction of the exotic brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae). The objective of this thesis is to enhance the understanding of Pentatomidae-Scelionidae host-parasitoid interactions from a behavioural ecology perspective, …

Competition Among Three Forensically Important Blow Fly Species (Diptera: Calliphoridae): Phormia Regina, Lucilia Sericata, And Chrysomya Rufifacies, Amber Macinnis

School of Natural Resources: Dissertations, Theses, and Student Research

The aim of this study was to use interspecific competition between three species of blow flies (Diptera: Calliphoridae) to determine if interspecific competition might explain the successional patterns. A replacement series model was used for three species of blowflies: Phormia regina, Lucilia sericata, and Chrysomya rufifacies. A total of 20 maggots were used for each treatment and the proportion of each species was varied. The graphic evidence and the relative crowding coefficient of P. regina versus L. sericata indicated a significant competitive advantage of P. regina. One of the life history traits of L. sericata is that it oviposits on …

Perch Selection By Male Dragonflies (Odonata, Anisoptera) Related To Competitive Ability And Species Composition, Jessica L. Beard

Biological Sciences Theses & Dissertations

Males of many species of dragonflies (Odonata, Anisoptera) establish territories in aquatic habitats where they compete with other males for access to food and females. Territorial males typically perch on emergent vegetation and chase rival males who intrude into their territories. This dissertation research examined the role of male size in perch height selection, position on the perch, and competitive ability. Four hypotheses were tested: 1) Dragonfly species would vary by size and that territorial species would show sexual size dimorphism (SSD), 2) Perch height selection would be related to dragonfly size, 3) Position on the perch would be related …

Multimodal Signalling In The North American Barn Swallow: A Phenotype Network Approach, Daizaburo Shizuka, Matthew R. Wilkins, Maxwell Joseph, Joanna K. Hubbard, Rebecca Safran

Papers in Behavior in Biological Sciences

Complex signals, involving multiple components within and across modal- ities, are common in animal communication. However, decomposing complex signals into traits and their interactions remains a fundamental challenge for studies of phenotype evolution. We apply a novel phenotype network approach for studying complex signal evolution in the North American barn swallow (Hirundo rustica erythrogaster). We integrate model testing with correlation-based phenotype networks to infer the contributions of female mate choice and male–male competition to the evolution of barn swallow communication. Overall, the best predictors of mate choice were distinct from those for competition, while moderate functional overlap suggests …

A Tragedy Exposed? Clear Growth Medium Reveals Competing Roots, Christopher H. Karounos, Deric Miller, Philip Crowley, Nicholas Mcletchie

Kaleidoscope

Abstract

Tragedy of the Commons (ToC) is the exploitation of an open-access resource that is exploited by selfish individuals to the detriment of all. Examples include open sea fisheries, cattle grazing, pollution, deforestation and plants competing over shared soil nutrients and space. Tragically, these resources become depleted and plants become severely resource limited. Our study seeks to determine if a ToC causes two plants sharing resources to reproduce less successfully than two plants owning the equivalent amount of personal resources. We predict that plant root competition creates a ToC by increasing root mass while reducing reproductive mass. Our study uses …

Application Of Qualitative Behavioural Assessment To Horses During An Endurance Ride, Patricia A. Fleming, Cheree L. Paisley, Anne L. Barnes, Françoise Wemelsfelder

Sentience Collection

Endurance horses are considered subject to a unique set of training and competing pressures due to the long distances travelled. The health and welfare of these horses could be compromised if they have not been adequately trained or are pushed beyond their limits, and there are increasing concerns regarding the capacity of horses to cope with the exercise demands placed on them, with high elimination rates for lameness and metabolic reasons. Veterinary inspections during these rides are important for assessing physiological measures, but the inclusion of behavioural assessments is also warranted. We investigated the application of Qualitative Behavioural Assessment (QBA) …

Winter Microhabitat Foraging Preferences Of Sympatric Boreal And Black-Capped Chickadees In Michigan's Upper Peninsula, Alec R. Lindsay Ph. D., Zach G. Gayk

Faculty Works

We examined differences in microhab- itat use between Boreal (Poecile hudsonicus) and Black- capped chickadees (P. atricapillus) where they co-occur near Marquette, Michigan, USA. Twenty-four Boreal and 37 Black-capped chickadees were followed during 60 hrs of field observation. Boreal Chickadees foraged only in three conifer species, 76% of which were black spruce (Picea mariana), while Black-capped Chickadees foraged widely across six coniferous and three deciduous tree species. Analysis of foraging data categorized by zones within conifer trees indicated high niche overlap (0.676) between Boreal and Black-capped chickadees across all foraging zones. Individual comparisons on a zone-by-zone basis revealed a significant …

Intraspecific Density Dependence And A Guild Of Consumers Coexisting On One Resource, Mark A. Mcpeek

Dartmouth Scholarship

The importance of negative intraspecific density dependence to promoting species coexistence in a community is well accepted. However, such mechanisms are typically omitted from more explicit models of community dynamics. Here I analyze a variation of the Rosenzweig-MacArthur consumer–resource model that includes negative intraspecific density dependence for consumers to explore its effect on the coexistence of multiple consumers feeding on a single resource. This analysis demonstrates that a guild of multiple consumers can easily coexist on a single resource if each limits its own abundance to some degree, and stronger intraspecific density dependence permits a wider variety of consumers to …

Possible Competition Between Waterfowl And Sandhill Cranes At Hiwassee Wildlife Refuge, Tennessee, David A. Aborn

Proceedings of the North American Crane Workshop

As a result of crop planting for waterfowl, numbers of eastern greater sandhill cranes (Grus canadensis tabida) staging and overwintering at the Hiwassee Wildlife Refuge in eastern Tennessee have sharply increased over the last 30-40 years. Peak numbers of wintering cranes have reached 14,000, and this large increase in crane numbers raises the possibility that they may be competing with waterfowl for food and space. I examined broad-scale changes in waterfowl numbers using Christmas Bird Count data, as well as small-scale changes using observations of waterfowl numbers and locations in relation to cranes on individual days. Preliminary results …

Do Arctic-Nesting Geese Compete With Sandhill Cranes For Waste Corn In The Central Platte River Valley, Nebraska?, Gary L. Krapu, David A. Brandt, Robert R. Cox Jr.

Proceedings of the North American Crane Workshop

Numbers of arctic-nesting geese staging in spring in the Central Platte River Valley (CPRV) of southcentral Nebraska increased dramatically from the 1970s to the 1990s, raising concerns that geese may be competing with the mid-continental population of sandhill cranes (Grus canadensis) for waste corn. From late February to mid-April 1998-2001, we measured temporal patterns of cropland use, evaluated habitat preferences, and compared numbers of geese using the primary crane-occupied parts of the CPRV area with numbers of sandhill cranes. Numbers of Canada geese (Branta canadensis), lesser snow geese (Chen caerulescens)/ Ross’ geese (Chen …