Other Animal Sciences Commons^™

Unintended Facilitation Between Marine Consumers Generates Enhanced Mortality For Their Shared Prey, F. Joel Fodrie, Matthew D. Kenworthy, Sean P. Powers

University Faculty and Staff Publications

We manipulated predator densities and prey vulnerability to explore how interactions between two predators affect overall mortality of their shared prey. Our threemember study system included eastern oysters (Crassostrea virginica) and two of its major consumers: southern oyster drills (Stramonita haemastoma) and stone crabs (Menippe adina). Field experiments demonstrated that drills and crabs foraging together generated higher than expected oyster mortality based on each species operating independently, even though crabs also killed some drills. In subsequent laboratory trials, we experimentally mimicked the handling of oysters by foraging crabs and confirmed that crabs facilitated drills by breeching oyster valves, thereby granting …

Effect Of Age And Tissue Weight On The Cadmium Concentration In Pacific Oysters (Crassostrea Gigas), Rosalee S. Hellberg, Michael T. Morrissey, Dan Cheney

Food Science Faculty Articles and Research

This study investigated the influence of age and tissue weight on cadmium (Cd) levels in Pacific oysters (Crassostrea gigas). Oysters from 4 different age groups (1, 2, 3, and 4 y) were collected at an oyster farm in Willapa Bay, Washington. To examine the effects of age, 60 oysters from each group were sorted into 3 composites of 20, and Cd analysis was carried out on all composite samples. To study the effects of tissue weights, 25 oysters from each of the 4 age groups were collected and analyzed individually for Cd. All oyster Cd concentrations were below …

Predators And Life Histories Shape Lestes Damselfly Assemblages Along A Freshwater Habitat Gradient, Robby Stoks, Mark A. Mcpeek

Dartmouth Scholarship

Survey data from New England showed that assemblages of Lestes dam- selflies are organized along the entire gradient of pond permanence and predator presence. One assemblage occupies vernal ponds lacking large dragonfly predators and fish; four are largely confined to temporary ponds that typically contain dragonfly predators; one dom- inates fishless permanent ponds and lakes where dragonflies are the top predators; and one dominates permanent ponds and lakes where fish are the top predators. We determined the role of life history and predation in maintaining this striking pattern by conducting a series of transplant experiments in the field and a …

Comparisons In Morphology, Reproductive Status, And Feeding Ecology Of Plethodon Cinereus At High And Low Elevations In West Virginia, Mizuki Takahashi

Theses, Dissertations and Capstones

To develop effects of elevation on morphological features, reproductive status, and feeding ecology of Plethodon cinereus in West Virginia, overall comparisons between high (>4000 ft) and low (<1260 ft) elevation populations were made. Adult P. cinereus from high elevations were smaller in SVL (female: p=0.003, male: p<0.001), but stored larger amounts of fat (female: p=0.041, male: p=0.006) in their tails than fromlow elevations. Larger amounts of tail fat could be an adaptation to harsh environments at high elevations. It was determined that in West Virginia, where as females at low elevations oviposit annually, females at high elevations oviposit biennially. Stomach content analysis revealed that salamanders at high elevations were confronted by food shortage. Because of less prey availability and longer winters at high elevations, salamanders at high elevations attained the smaller body size than at low elevations and could not obtain sufficient energy in 1 year to yolk a clutch.

A Cladistic Analysis And Taxonomic Revision Of The Plesiosauria (Reptilia: Sauropterygia), F. Robin O’Keefe

Biological Sciences Faculty Research

The Plesiosauria (Reptilia: Sauropterygia) is a group of Mesozoic marine reptiles known from abundant material, with specimens described from all continents. The group originated very near the Triassic–Jurassic boundary and persisted to the end- Cretaceous mass extinction. This study describes the results of a specimen-based cladistic study of the Plesiosauria, based on examination of 34 taxa scored for 166 morphological characters. The Pliosauroidea is found to by polyphyletic due to the inclusion of the Polycotylidae; this second clade is instead a member of the Plesiosauroidea, and thus more closely related to elasmosaurs than to other ‘pliosaurs’. Characters of body proportion …

Intraintestinal Sites Of Infection For The Trematode Species Plagitura Salamandra Holl 1928 And Plagitura Parva Stunkard 1933 In Red-Spotted Newts Notopthalmus V. Viridescens (Rafinesque), Jeremy T. Clay

Theses, Dissertations and Capstones

The red-spotted newt, Notopthalmus v. viridescens (Rafinesque) is a common salamander in the eastern United States. Studies on the parasites are available, however these studies examined total parasite fauna. This study examines two species, Plagitura salamandra Holl 1928 and Plagitura parva Stunkard 1933 found in the small intestine of the red-spotted newt. A total of 225 newts was collected and examined for the two Plagitura species. No difference was found in prevalence of infection, mean intensity, SVL, and weight between male and female newts. Plagitura parva was found in 24.4 % of the newts while P. salamandra was found in …

Natural History Of The Four-Toed Salamander, Hemidactylium Scutatum, In West Virginia, Sandra L. Kilpatrick

Theses, Dissertations and Capstones

A 2-year study was conducted to determine the reproductive and nesting habits, embryonic and larval development, and tolerance to acid conditions of Hemidactylium scutatum in West Virginia. Five study sites located in or adjacent to the Otter Creek National Wilderness Area, Monongahela National Forest, Randolph County, West Virginia, were monitored to determine nesting habits and length of incubation and larval periods in Hemidactylium Time of breeding was determined by spermatogenic wave analysis and time of egg deposition was determined by examination of ovarian follicles and field observations of gravid females migrating to nest sites. Breeding occurred in autumn and again …

Lists Of Larval Worms From Marine Invertebrates Of The Pacific Coast Of North America, Hilda Lei Ching

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Immature stages of seventy-three digenetic trematodes are listed by their families, marine invertebrate hosts, and localities and then cross listed according to their molluscan hosts. The list contains many new host records, and larval stages of fifteen digenetic trematodes were newly recorded from gastropods from British Columbia and California. A list of immature stages of fourteen cestodes, acanthocephaIans, and nematodes is also included.

Proceedings -- National Wilderness Research Conference: Current Research, United States Department Of Agriculture, Forest Service

Forestry

Includes more than 70 reports of current wilderness research. Papers are organized around nine topics: wilderness resource research, including natural fire, air quality, impacts to soil and vegetation, fish and wildlife, and water; and wilderness user research related to recreational use and user characteristics, attitudes and behavior, benefits, and management concepts and tools.

Meteorological Factors Controlling The Emergence Of The Eastern Spadefoot Toad, Scaphiopus Holbrooki Holbrookii Harlan, Larry Judy

Theses, Dissertations and Capstones

Scaphiopus holbrooki holbrookii, the Eastern Spadefoot, can exist in an area for many years before it is detected. Its apparent scarcity can be explained by its secretive, fossorial habitat, protective coloration, and nocturnal behavior. Spadefoots are present at the surface locally in small numbers on any one night. They emerge only when conditions are optimum. One authority has suggested that temperature, moisture, and barometric pressure exert control over emergence.

It was the purpose of this research to discover the most important meterorological parameters and investigate how they control the behavior of Scaphiopus.

Initially the response, emergence to breed was distinguished …