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A Comparison Of Macrofaunal And Algal Communities In Oyster Aquaculture Gear, An Eelgrass Bed, Oyster Reef, And A Mudflat In Great Bay, New Hampshire, Megan Elizabeth Glenn

Master's Theses and Capstones

Oysters (Crassostrea virginica) and eelgrass (Zostera marina) are important ecosystem engineers in Great Bay, NH, however despite restoration efforts they have been in decline. In addition to loss of the resource, this degradation results in loss of associated ecosystem services such as habitat provision. It is possible that the recent increase in oyster farming in Great Bay could help mitigate habitat loss. My research objective was to quantify the biotic communities present in three natural habitats (eelgrass beds, oyster reefs and mudflats) in Great Bay NH and compare those to communities living on the type of gear (“racks and bags”) …

Ecosystem Structure And Function In An Urban, Piped Stream, Amanda Hope

Master's Theses and Capstones

Piped streams, or streams that run underground, are common features in urban areas. However, there is little empirical evidence regarding their ecological structure and function. This study measured ecosystem metabolism, nutrient uptake, and related characteristics of Pettee Brook -- an urban stream that flows through several pipes under impervious surfaces near the UNH (Durham) campus.

Piped and open reaches of Pettee Brook had similar water quality, nutrient uptake, and ER. However, the absence of light in piped reaches led to their complete loss of GPP. Benthic AFDM and chlorophyll a biomass were also significantly reduced in piped reaches. For both …

Isotopic Analysis Of Arctic Ground Squirrel Tissues And Potential Food Sources, Julee Shamhart

Master's Theses and Capstones

Given limited knowledge of the food sources of Arctic ground squirrels, an important arctic prey species, it is difficult to predict the implications of changes in food source availability that could result from climate change. I hypothesized that Arctic ground squirrels at two colonies, Atigun and Toolik, would have similar feeding habits and mushrooms would contribute to their diet The Arctic ground squirrels at Toolik had significantly higher del15N (3.7 per mill difference) and del13C values (1.3 per mill difference) than those at Atigun. Mixing models indicated that the signatures observed in the Atigun hair could result from a combination …

A New Perspective: Atlantic Herring (Clupea Harengus) As A Case Study For Time Series Analysis And Historical Data, Emily Klein

Master's Theses and Capstones

This thesis endeavors to develop methods for the historical analysis of a specific species and location to begin understanding fishery patterns and change over time. The main goal was to develop statistical methods to address historical data and provide long-term information on fishery trends and potential relationships between the fishery and outside influences. The Atlantic herring (Clupea harengus) fishery was investigated for underlying patterns and the possible impact of outside variables and events from 1870 to 2007.

In the Gulf of Maine, Atlantic herring (Clupea harengus) provide critical forage for many economically valuable species, while supporting a major New England …

Early Performance Of Constructed Oyster Reefs In Great Bay, New Hampshire, Mark K. Capone

Master's Theses and Capstones

Several oyster reefs were constructed in Great Bay, New Hampshire using remotely-set oysters. A single large reef treatment and a cluster of several small reefs treatment were utilized to test hypotheses relevant to oyster restoration design, and to monitor early restoration reef performance. There was no significant difference in oyster size, density, and recruitment between two experimental reef structures, with both reef types having high survival and fast growth rates for the 2-year study. Both experimental reef structures had significantly higher recruitment rates than natural reefs in 2006, a year of relatively high recruitment (p < 0.05), and elevated yet not significantly higher recruitment rates in 2005, a weak recruitment year (p = 0.078). In situ fluorometry data showed that a restored reef can significantly impact chlorophyll-a levels in overlying water within two years of reef construction. Individual oyster clearance rates ranged from 1.87 L/hr--2.41L/hr.

Field Efficiency And Bias Of Several Methods For Downed Wood And Snag Inventory In Western North American Forests, Robert Scott Kenning

Master's Theses and Capstones

Coarse woody debris (CWD)---downed forest wood and snags---has been afforded increasing attention in the past decade as studies illuminate the role of dead wood in the study of global carbon cycling, wildlife, forest fire, and soil ecology. Accordingly, the need for efficient sampling methods of CWD has grown. This study compares the field efficiency and bias of seven traditional and novel sampling techniques. Methods were tested in 14 forest stands across 3 broad study regions---alpine and ponderosa forests in Colorado and coastal rainforest in British Columbia.

For sampling downed wood volume, perpendicular distance sampling (PDS) proves to be the most …

Effects Of Forest Clear Cutting On Spotted Salamander ( Ambystoma Maculatum) Migration, Jessica Susannah Veysey

Master's Theses and Capstones

Upland buffer zones are a proposed management tool for vernal-pool-breeding amphibians. Substantial validation of buffers, via experimental upland habitat disturbance, is lacking. Specifically, no studies have examined immediate effects of clear cutting on spotted salamander (Ambystoma maculatum ) migration. I used clear cutting to experimentally manipulate upland buffer widths at 11 vernal pools. I then radiotracked 40 adult spotted salamanders at these pools, and modeled their migration with mixed-effects regression. Mean maximum distance from the pool was 106.0 +/- 15.4 m (range = 1.6 to 427.6 m). At clear cut-treatment pools, mean percent of time in the cut was 27.2 …

A Test Of The Nutrient-Productivity Model In The Gulf Of Maine Using The Intertidal Mussel Mytilus Edulis, Meredith A. Bailey

Master's Theses and Capstones

Historical concepts of top-down control (predator-prey interactions) on rocky intertidal community structure have transitioned to studies on bottom-up effects (nutrient supply and larval transport) as significant factors affecting rocky intertidal community structure. Studies performed on rocky intertidal locations along the Gulf of Maine (GOM) at multiple sites and seasons in 2004 and 2006 examined the ecology of Mytilus edulis populations by measuring size frequency distributions, diet quality (stable isotope composition) and physiological performance of individuals using condition indices and RNA/DNA ratios. Data were correlated to satellite imagery for sea surface temperature and chlorophyll a concentration and individuals were genetically tested …