Life Sciences Commons^™

On Global Change, Direct And Indirect Interactions, And The Structure Of Ecological Communities: Theoretical And Empirical Tests, Mariano Alberto Rodriguez Cabal

Doctoral Dissertations

Human induced global change (climate change, CO₂ enrichment, nitrogen deposition, habitat degradation and biological invasions) is the most serious threat to biodiversity. Understanding how ecosystems will respond to different components of global change, and how these responses will affect key ecological processes, has become essential in contemporary ecology. For example, several studies have shown that exotic invasive species have negative impacts on the composition of communities, habitat structure and ecosystem processes. Particularly, exotic species may have negative effects on species interactions due to local extinctions, competition and/or replacement of interactions. Despite the large body of research demonstrating the negative …

Multi-Level Impacts Of Introduced Wild Boar On Patagonian Ecosystems, Maria Noelia Barrios Garcia Moar

Doctoral Dissertations

Biological invasions are a pervasive global change that threatens biodiversity and the functioning of natural ecosystems, yet most studies focus on population impacts. Furthermore, the effects of invasive species on ecosystems are greatest when they introduce a novel disturbance. In this dissertation I reviewed the impact of wild boar (Sus scrofa) on native communities worldwide, identifying research needs. Wild boar overturns extensive areas of vegetation to feed on belowground plant parts, insects and fungi, thus altering native ecosystems integrity. By means of observational and experimental studies I addressed some of the research gaps on the impact of wild …

Discovering The Light Bulb Tunicate, James F. Reinhardt Phd, Margaret (Peg) A. Van_Patten (Editor) Ms.

Wrack Lines

An article by a former UCONN marine sciences graduate student about a new invasive tunicate in Long Island Sound, the light bulb tunicate.

Survival, Growth And Reproduction Of Non-Native Nile Tilapia Ii: Fundamental Niche Projections And Invasion Potential In The Northern Gulf Of Mexico, Michael R. Lowe, Wei Wu, Mark S. Peterson, Nancy J. Brown-Peterson, William T. Slack, Pamela J. Schofield

Faculty Publications

Understanding the fundamental niche of invasive species facilitates our ability to predict both dispersal patterns and invasion success and therefore provides the basis for better-informed conservation and management policies. Here we focus on Nile tilapia (Oreochromis niloticus Linnaeus, 1758), one of the most widely cultured fish worldwide and a species that has escaped local aquaculture facilities to become established in a coastal-draining river in Mississippi (northern Gulf of Mexico). Using empirical physiological data, logistic regression models were developed to predict the probabilities of Nile tilapia survival, growth, and reproduction at different combinations of temperature (14 and 30°C) and salinity …

Macrophyte Communities Of Lake Winnebago: Baseline Study Of Species Composition With Abundances And Water Quality Conditions, Mackenzie Kessenich

Lawrence University Honors Projects

Historical records from Lake Winnebago show minimal macrophyte growth; however, reports from recent years claim that macrophyte growth in some areas of the lake has reached nuisance levels. This study aimed to investigate the species of macrophytes present and their abundances in four near-shore locations, as well as measurements of multiple water quality conditions. Rake sampling was used to identify species and quantify their abundances and distributions. In addition, data were collected on light penetration, Secchi depths, and suspended algae chlorophyll concentrations at each site. These data from shallow near-shore sites reveal trends in changing water clarity and light penetration …

Exploring The Seed Bank Dynamics Of Red Brome: Longevity, Density, And Relationship To Fire, Benjamin S. Jurand

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research explores several untested aspects of the seed bank characteristics of red brome (Bromus rubens), an invasive annual grass in southwestern United States arid lands. Red brome is a formidable competitor to native plant species, both annual and perennial alike, and produces many seeds that germinate easily. The stalks of red brome contribute continuous-cover fuel loads that facilitate wildfires destructive to mature native Mojave Desert plant communities. This makes it a priority species for land managers, particularly when dealing with recovery after fire.

This project addressed questions related to the longevity of red brome seeds in soil seed banks …

The Effects Of Invasive Grasses On The Survival And Germination Of Native Forbs, Rachel A. King

Scripps Senior Theses

Invasive species are an increasingly severe conservation problem that can dramatically alter native plant communities. Although ecologists have proposed many mechanisms for the dominance of invasive species, superior competitive ability is one of the longest standing hypotheses. In winter annual plant communities, germination timing affects competition among plants. I hypothesized that grass invasion has changed the costs and benefits of early and late germination, and that species with flexible germination timing would compete better with invasives. Experiments at the Bernard Field Station in Claremont, CA and germinator trials in a controlled environment were used to examine the survivorship and germination …

Efficacy Of Aerial Broadcast Baiting In Reducing, Larry Clark

Larry Clark

The brown treesnake (Boiga irregularis) is an invasive predator that was introduced on Guam as a stowaway in cargo after World War II. Since then, the population has exploded, attaining 50 to 100 snakes per ha in some areas. The snake has caused the extirpation of ten of the 12 native forest bird species on Guam. The U.S. Department of Agriculture, Wildlife Services, has a program to deter the spread of snakes from Guam to other islands. Hand capture from fences, trapping, toxic bait stations, and canine inspection of outbound cargo methods are used in the control program in various …

Efficacy, Effort, And Cost Comparisons Of Trapping, Larry Clark

Larry Clark

Brown treesnakes (Boiga irregularis) are an invasive species to the island of Guam. Because they have extirpated the native forest avifauna on Guam and are a threat to other Pacifi c islands, the development of effi cient and cost-effective methods to control them is desired. We compared the effi cacy, cost, and effort required to remove brown treesnakes on 6-ha plots in forest scrub on Guam, using 2 methods: trapping and poison baiting. Toxic baits consisted of dead neonatal mice adulterated with 80-mg acetaminophen. To assess effi cacy, we used mark-recapture methods to estimate snake abundance on plots 12 days …

Despite Losing Its Mittens, A Chinese Mitten Crab Finds Its Way To Connecticut, Nancy C. Balcom

Wrack Lines

A new invasive species for Connecticut: the Chinese mitten crab. Only one of this invasive crustacean species was spotted, but there will be more on the way.