Life Sciences Commons^™

Practical Solutions To The Invasion Of Lionfish In Utila, Honduras: Science, Education, Food, And Jewelry, Carolyn Corley

Undergraduate Honors Theses

Lionfish (Pterois sp.) are invasive species capable of devastating coral reef ecosystems due to their lack of predators, large appetites, generalist diet, high fecundity, and rapid spawning rates. As lionfish have expanded their distribution across the Caribbean, many conservation groups have taken it upon themselves to systematically remove these predators from environments where they are threatening native species. However, few have involved the community the way I observed while interning with the Whale Shark and Oceanic Research Center in Utila, Honduras. Protecting coral reefs is extremely important, especially in small communities like Utila, where the majority of people’s …

Crassostrea Gigas Invasion In Southern California: Macrofaunal Diversity And Local Community Impacts Of Ecosystem Engineers On Estuarine Habitats, Noah Jansen-Yee

Theses

Many marine ecosystems are facing the growing threat of biological invasions. These invasions can have a variety of different impacts on ecosystems and their inhabitants. The Pacific oyster, Crassostrea gigas, is currently in the relatively early stages of invasion in San Diego estuaries. Crassostrea gigas is a large, filter-feeding bivalve that forms dense oyster beds on hard substrate. These oysters are known to outcompete native counterparts and drastically alter habitats where they are present. Crassostrea gigas is an ecosystem engineer that, through shell creation and formation of a dense oyster matrix, impacts ecosystems in a variety of direct and indirect …

La Habana: A History Of Society, Livelihood, Movement, And Land Use On The Iquitos-Nauta Highway, Katie Brown

Undergraduate Honors Theses

With increasing infrastructural projects and land titling in the Peruvian Amazon, many changes are occurring within small roadside communities. In this case study, we investigate how these changes impact livelihoods, land use, travel patterns, and social relations within the broader concepts of development, privatization of land, and commodification of nature. Specifically we focus on the caserío La Habana situated on the Iquitos-Nauta highway in the Loreto region of Peru. Semi-formal interviews and ethnographic methods were conducted to gather information on social organization, history of the community, land use practices, migration patterns, opinions on the road, and livelihood strategies. After data …

The Distribution And Demography Of The Invasive Pacific Oyster, Crassostrea Gigas, And Native Olympia Oyster, Ostrea Lurida, In The San Diego River, Jason Langevin

Theses

Even though the introduction of the Pacific Oyster, Crassostrea gigas, to the west coast of North America, happened roughly a century ago, it has only been in the past 15 to 20 years that C. gigas has started to become an established and conspicuous species along Southern California’s coast. The establishment of C. gigas in Southern California has the potential to heavily influence many native species, as it has done globally. In Southern California, this invasion is particularly relevant for the native Olympia Oyster, Ostrea lurida. The Olympia oyster has both historical and present-day threats to its population, …

Spatial And Temporal Variation In The Diet Composition Of Zooplankton In Mission Bay, Bryanna Paulson

Theses

Analyses of quantitative data on zooplankton diets are vital for understanding the drivers of zooplankton abundance within an ecosystem. Such analyses also provide insight into trophic pathways within the lower planktonic food web, which support populations of higher trophic level species. This study used carbon and nitrogen stable isotope ratios of size-fractionated plankton in Mission Bay, San Diego, CA to examine the spatial and temporal variation in zooplankton trophic ecology and determine potential environmental drivers of zooplankton community structure. Carbon stable isotopes reflect primary production sources in an organism’s diet, and nitrogen stable isotope ratios can be used to estimate …

Daphnia: A Possible Way To Combat A Deadly Amphibian Pathogen, Taylor Thomas

Undergraduate Honors Theses

Globally there is a biodiversity crisis, with many groups of species threatened with extinction due to changes in the environment and human impacts. Amphibians are one such group and according to the IUCN, over 30% of amphibians are threatened by extinction. There are many factors have that can explain the decline of amphibians including pollution, habitat loss, climate change and disease. One factor is chytridiomycosis, an emerging infectious disease caused by the chytrid Batrachochytrium dendrobatidis. The chytrid enters the keratinized skin of the amphibian and asexually reproduces, where it disrupts host functions, often leading to host death.

Due to …

Investigation Into The Mechanism Of Ion Transport In Rio Negro Characiformes, Vineza D. Reduta

Undergraduate Honors Theses

Four fish species within the Characiform Order [(Rosy tetras (Hyphessobrycon rosaceus), Serpae tetras (Hyphessobrycon eques), Emperor tetras (Nematobrycon palmeri) and Penguin tetras (Thayeria obliqua)] are native to the ion-poor, acidic waters of the Rio Negro. In this paper, we focus on Wood’s revised Na⁺/NH₄⁺ exchange model to gain better insight into the mechanisms of ion transport within the Characids. We exposed each species to two experimental treatments: (i) 1mM ammonia (high external ammonia [HEA]), to test coupling of Na⁺ uptake and ammonia excretion, and (ii) 100μM Acetazolamide …

Tropical Trees As Islands: Diversity Accumulation Of Armored Scale Insects (Hemiptera: Diaspididae) On Trees As A Function Of Forest Age, Hannah Shapiro

Undergraduate Honors Theses

Armored scale insects (Hemiptera: Diaspididae) are some of the most invasive insects in the world. These cryptic plant parasites are most often encountered in managed agricultural ecosystems, but very little is known about their distribution, abundance, and diversity in tropical rainforest canopies, where they are likely to have their highest diversity. Because these ubiquitous insects are extreme generalists with undirected dispersal, their diversity (alpha and beta) accumulation can conceivably be modeled according to tenets derived from island biogeography theory. For example, one expectation is that older established trees should boast a higher species diversity and abundance than younger ones. Other …

The Suitability Of Habitats And The Effects Of Human Activities In Osupuko And Olepolos Wildlife Sanctuaries On Maasai Giraffes, Sydney P. Davis

Undergraduate Honors Theses

Habitat quality and resource availability within wildlife dispersal areas in the Amboseli ecosystem are experiencing degradation due to pastoralism and agriculture by humans, which negatively affects the wildlife species that utilize these dispersal areas. Maasai giraffes are a common species that utilize these areas, but information on how human activities and the presence of domestic livestock affects the Maasai giraffe is limited. This study was conducted in two wildlife sanctuaries: Osupuko and Olepolos. Habitat condition assessment was done to determine the quality of habitats found within each sanctuary. The Point-Centered Quadrat Method was used to determine the number of five …

Local Patterns In Host-Selection By Anemone Symbionts In Bocas Del Toro, Panama, Samantha Mercer

Undergraduate Honors Theses

The associations made between many symbiotic cleaner shrimps and their host anemone species are influenced by local ecological factors, resulting in regional variations in symbiont-host preferences. These relationships are crucial parts of aquatic ecosystems, and as we face rapid global environmental change, understanding the local patterns of this host specificity will be essential to maintaining healthy marine environments. However, sea anemones, as well as their symbiotic relationships, from the Caribbean coasts of Panama have been poorly studied and are largely under-represented in the current literature. The purpose of this study is to identify the local host-selection patterns, specifically regarding host-size …