253 research outputs found
EFFECTS OF ABIOTIC STRESS AND PREDATOR REFUGE ON TERRESTRIAL PREDATOR-PREY INTERACTIONS
Get PDFA major goal of ecology has been to understand how abiotic stress modifies species interactions, including predation. In marine habitats, a well-supported hypothesis holds that stress reduces the importance of predation because predators are more vulnerable to stress than prey, but this hypothesis has not been well-tested in terrestrial systems. The effect of refuge from stress on predation level has been studied even less, particularly in terrestrial systems. My research examines the effects of two types of stress, and refuge from them, on predation in a terrestrial salt-marsh food web.
I investigated the stress of winter weather and asked first, whether the top predator used a particular marsh habitat as a winter refuge, second, how inter-year variation in winter severity affected refuge use, and third, how refuge use affected the predator's spatial distribution later in the year (Chapter 1). I found that spring predator density was higher within the refuge than outside, a difference that increased following colder winters. Consequently, predators were forced to re-colonize the rest of the marsh from the winter refuge, creating a long-lasting density gradient with lower densities farther from the refuge. In contrast, prey densities were not affected by winter temperatures, and were higher outside the refuge. This prey distribution may have facilitated predator colonization of non-refuge habitats.
I investigated the stress of tidal inundation on marsh predators and prey, and their use of vegetation above water as a refuge from submersion. I found that densities of two key predators were more highly correlated with refuge availability than with tidal intensity. Notably, this correlation with refuge increased during the highest tides of the month. In contrast, distribution of the most abundant herbivore was not correlated with refuge availability (Chapter 2). These results suggested that tides impacted predators more than herbivores, but that refuge negated tidal effects on predators. To test these hypotheses, I eliminated tidal inundation from experimental field mesocosms while allowing control mesocosms to experience normal tides (Chapter 3). I found that tides caused substantial mortality at all trophic levels, but affected predators significantly more than herbivores and decreased predation levels
An Impact Evaluation of the 'Joy Project'
Get PDFThis report gives an overview of research undertaken to evaluate the impact of the JOY Project which is based in the City of Worcester, England. The project is "a woman only community project which provides support to enable women to gain a variety of skills, enhance their confidence and empower them to make their own informed decisions" (WCT, 2018a).
The evaluation considers the extent to which the project serves the local community by comparing data on service users with local socio-demographics and outlines the extent to which the project's aims and outcomes set by the funder, The Big Lottery Fund) are met. It highlights additional outcomes and captures the impact of project activities on service users. Ultimately, it draws conclusions about the quality, impact and value of the JOY Project
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