Habitat complexity and habitat function of native (Crassostrea virginica) and non-native (C. ariakensis) oysters in the Chesapeake Bay region

Complex oyster reefs created by the Eastern oyster, Crassostrea virginica, though once prominent features of the Chesapeake Bay region, have become relatively scarce in comparison to historic descriptions. This decline, caused by a combination of overfishing, disease, habitat destruction and pollution, this decline continues despite substantial restoration efforts that have spanned decades. In response to this decline, the states of Virginia and Maryland considered the intentional introduction of the non-native Suminoe oyster, C. ariakensis. Previous studies questioned the reef-building capability of this Crassostrea species, which may affect its habitat function. Through a combination of field and mesocosm studies, I examined the possibility that this non-native oyster species would provide an ecologically-functional equivalent of the native oyster species if introduced into Chesapeake Bay. Habitat complexity and associated benthic communities of experimental triploid C. virginica and C. ariakensis reefs were investigated at four sites of varying salinity, tidal regime, water depth, predation intensity and disease pressure in the Chesapeake Bay region (Virginia and Maryland). Four experimental treatments were established at each site: C. virginica; C. ariakensis; 50:50 of C. virginica: C. ariakensis; and shell only. Abundance, biomass, species richness, evenness, dominance and diversity of reef-associated fauna were evaluated in relation to habitat location and oyster species over a period of 21 months. Habitat complexity varied spatially, although no differences among complexity indices were associated with oyster species. Increases in vertical reef heights and surface rugosity were observed over time for all experimental reefs, and treatment effects were observed after 19 months of development, when C. ariakensis reefs exceeded the vertical heights of C. virginica reefs, removing any doubt regarding the Suminoe oyster\u27s reef-building capability. Spatial comparisons of reef-associated macrofauna suggested functional equivalency between oyster species with respect to habitat at intertidal locations (where C. ariakensis survival was low), and at subtidal sites of low salinity. at subtidal locations of higher salinities, however, the numbers of organisms associated with C. virginica reefs per unit of oyster biomass were significantly greater than the numbers of organisms associated with C. ariakensis. Multivariate analyses of data from subtidal high salinity sites also revealed unique communities associated with C. virginica treatments, while mixed oyster species assemblages were functionally equivalent to mono-specific C. ariakensis experimental treatments. Temporal comparisons at one mesohaline subtidal site revealed that the observed effects of oyster species on habitat function in higher salinity locations are inconsistent over time and likely overshadowed by seasonal larval recruitment dynamics and local hydrodynamics. Though a common oyster reef trophic cascade between juvenile oysters, C. virginica; mud crabs, Panopeus herbstii; and oyster toadfish, Opsanus tau was successfully replicated during mesocosm trials, specific trophic interactions were not significantly affected by oyster substrate species or habitat complexity (as it was defined within the constraints of the experiment). Together, these experiments represent the first effort to quantify the potential habitat function of C. ariakensis in Chesapeake Bay, and provide evidence of species-specific similarities and differences in reef-associated communities

Landscape aspects of oyster reefs : fragmentation and habitat utilization

The functional value of oyster reefs is recognized in many estuarine systems, with increasing interest in oyster reef restoration for ecological function rather than for fishery production. Reefs provide structure and refuge for juvenile fish and crustaceans, and may be a locus for predator foraging. However, reef morphology influences the relative value of refuge and forage functions, and reef utilization by benthic, epibenthic, and nektonic organisms. Reef fragmentation will increase the edge to interior ratio, and may enhance use by organisms that favor edge regions, or decrease use by species requiring more interior habitat. The influence of fragmentation was examined using created intertidal oyster reefs and natural reef patches in southeastern North Carolina. Created reef treatments included a uniform circular reef, a small fragmented reef, a large fragmented reef, and reference natural reef and mudflat areas. In addition, uniform and fragmented patch reefs in two nearby tidal creeks were also sampled. All treatments were sampled immediately after construction in June 2002, and then quarterly over two years, targeting infauna, epifauna, and nekton. Effects of fragmentation on infuana were variable, with a combination of positive and negative species-specific responses. However, preferential use of large fragmented reefs over small fragmented reefs was observed for Lagodon rhomboides, Panopeus herbstii, and Geukensia demissa, suggesting that the small fragmented reefs were most likely below the patch size threshold at which edge effects become beneficial. Implications are that oyster reef fragmentation may be an important factor for restoration managers to consider when designing reefs in which increased habitat utilization is a primary goal. Although a degree of fragmentation may be beneficial for some species, once fragmentation leads to a loss of reef area below critical thresholds, degradation effects on habitat utilization could be great

The Effect of Storm Events on Diet of Adult Mummichogs (Fundulus heteroclitus)

More frequent storms due to climate change may impact estuarine species such as the mummichog (Fundulus hetereoclitus), an ecologically important salt marsh fish. This study investigated the effect of storm events and month on consumption of terrestrial insects by mummichogs in Hoffler Creek, Portsmouth, VA, as well as the effect of storms on consumption of major categories of benthic prey. Samples were taken monthly in the summers of 2017 and 2019. Additional paired samples were taken in June and July 2019, with the first collection during dry weather and the second during a subsequent storm. Month had a significant effect on the proportion of terrestrial insect prey in the diet in both years; consumption was highest in August, particularly in 2017 when the sample coincided with a storm event. However, storms increased consumption of terrestrial insects in only one of four paired dry weather-storm samples in 2019, indicating that temporal variation in insect abundance has a larger effect than increased availability that might occur when storms knock insects into the water. Storms had a significant effect on the proportion of different benthic prey in the diet in paired samples from 2019, but these effects were not consistent across months, sites, or in whether storms increased or decreased consumption. These patterns may be driven by mummichogs taking advantage of small-scale temporal or spatial variation in benthic prey. The ability to utilize locally abundant resources, including terrestrial insects, may help minimize the negative impacts of climate change on mummichogs

Using Student Opinion and Design Inputs to Develop An Informed University Foodservice Menu

The potential for Universities and Colleges to be settings that promote health and wellbeing has become the subject for debate where the role of foodservice has been acknowledged as influential. The aim of this research was to evaluate an effective design to promote healthy selections from university foodservice menus. The research was designed around a grounded theory approach utilizing semiological prompts based on different existing nutrition labeling schemes. A total of 39 students (17 male, 22 female) participated in seven focus groups at Montclair State University, US. The participants of this study clearly called for nutrition labeling on college menus and a prototype design had been agreed. The students also itemized five nutrients they wanted listed in a Traffic Light system of colors and then quantified on the menu: calories, sodium, sugar, fat and carbohydrates, plus beneficial ingredients or nutrients for display in menu icons. The nutrients and display order varies somewhat from industry and government standards, though the student recommendations are suggestive of common understandings of published nutrient guidelines. Students have a stake in how menu information is presented on campus and their opinions could positively impact the general selection of healthy foods

An Index of Human Well-Being for the U.S.: A TRIO Approach

In 2011, the US Environmental Protection Agency’s (EPA) Office of Research and Development program, Sustainable and Healthy Communities, coined the term TRIO (Total Resources Impact Outcome) to represent approaches that fully incorporate all three pillars of community sustainability—environmental, economic and social. This holistic approach to sustainability is embodied in the Human Well-Being Index (HWBI) comprised of sub-indices representing environmental well-being, economic well-being and societal well-being (which includes basic human needs and subjective well-being). The development of the HWBI is described in this manuscript along with its application at national, state and county spatial scales. In addition, application at even smaller spatial scales (communities, neighborhoods, demographic and economic sub-groups, and even individuals) is discussed. The potential utility of HWBI for comparing the intended and unintended consequences of alternative decisions is described