Ecosystem Services of Restored Oyster Reefs in a Chesapeake Bay Tributary: Abundance and Foraging of Estuarine Fishes

Oyster reef restoration may enhance the production of ecologically or economically important fish species, an ecosystem service, by providing refuge and foraging habitat. Predicting the effects of oyster habitat restoration on fisheries production in Chesapeake Bay requires a better understanding of fish habitat use, trophic dynamics, and the processes leading to production on a habitat-scale. The objective of this thesis was to evaluate the influence of restored subtidal oyster reefs on the abundance and foraging patterns of mobile estuarine fishes. Specifically, I compared the 1) abundance, 2) stomach fullness, 3) diet composition, and 4) daily consumption rate of fishes collected from restored oyster reef habitat and from unstructured (control) habitat in the Lynnhaven River System (LRS), Virginia, a tributary of Chesapeake Bay. I sampled fishes from April – October 2016 to assess seasonal abundance and diet trends using multi-panel gill nets, and conducted 24-hour sampling events in July and September 2016 to assess daily foraging patterns and estimate habitat-specific consumption rates. The most abundant non-filter feeding fishes collected all came from the Sciaenid (drum) family: spot (Leiostomus xanthurus), silver perch (Bairdiella chrysoura), and Atlantic croaker (Micropogonias undulatus). Overall catch in oyster reef habitat was reduced relative to unstructured bottom, but species-level responses to habitat type varied. Stomach fullness trends varied by species but were associated with habitat type. Benthic prey dominated the diet of all three species, and evidence of habitat-related shifts in diet composition were apparent. Reef-affiliated prey contributed most prominently to silver perch, comprising nearly 30 – 50 % by weight. The daily consumption rate and total daily caloric intake of silver perch foraging in oyster reef habitat were nearly double the estimates from control habitat. The results suggest restored oyster reefs influence habitat use and foraging behavior in species-specific manners, likely a result of differences in functional morphology and prey preference. Restored oyster reefs in the LRS likely act as valuable forage habitat for silver perch, an important trophic link in coastal and estuarine systems. Developing realistic estimates of fisheries production on a habitat-scale requires studying species-specific trophic dynamics. Empirical estimates of the processes contributing to production are necessary to better understand the functional role of restored oyster reefs in shallow estuarine and coastal systems, and the ecosystem services these reefs may provide

Quantifying finfish and blue crab use of created oyster reefs in the lower Chesapeake Bay

Structurally complex reefs created by the eastern oyster Crassostrea virginica provide a host of ecosystem services yet have experienced significant declines, prompting extensive restoration efforts. We investigate the use of created oyster reefs in the lower Bay by mobile finfish and blue crabs with field surveys and diet analysis. The results of this study provide insight into how restoration activities influence estuarine community dynamics and the provision of ecosystem services

The lumbar spine of the young cricket fast bowler: An MRI study

Objectives: To describe the prevalence and nature of lumbar spinal abnormalities in adolescent cricket fast bowlers. Design: Observational study. Methods: 46 asymptomatic fast bowlers aged 13-18 years participated in the study and were grouped into under-15 (U15), under-17 (U17) and under-19 (U19) classifications. All participants underwent magnetic resonance imaging of the lumbar spine and abnormalities of the pars interarticularis and intervertebral discs were graded according to type and severity. Other abnormalities were also noted. Results: Fifteen bowlers (33%) had at least one pars interarticularis abnormality. Six bilateral and 10 unilateral defects were identified. Of the 10 unilateral pars abnormalities, 6 occurred on the non-dominant side. Nineteen of the abnormalities occurred at the L5 vertebral level, 2 at L4 and 1 at L3. The most common type of pars abnormality was the subtotal stress fracture, which was found in 38% of bowlers aged 16 years and under. Sixteen participants (35%) were found to have degeneration of at least 1 lumbar disc and the prevalence increased with each successive age group (29% U15, 33% U17 and 43% U19). Of the 25 discs with signs of degeneration, 9 occurred at L4/5 and 7 at L5/S1. Eleven of these were classified as mild degeneration, 13 as moderate, and 1 as severe. Disc bulges were found in 33% of participants. Conclusions: Lumbar radiological abnormalities are common in asymptomatic adolescent fast bowlers. Acute bone stress reactions of the lumbar pars interarticularis are visible on magnetic resonance imaging and, in some instances, occur before the onset of activity-related pain. © 2011

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field