Project overview:

In this project we are generally interested in understanding how food web interactions and dynamics can
better inform the management of individual species. Lake Norman is a 32,000+acre reservoir north of Charlotte, NC that has experienced
a number of recent species introductions. The impact of these introductions on sportfish recruitment and dynamics is not well understood.
Through this joint NC State, NC Wildlife Resources Commission, and Duke Enery research project, we broadly consider interactions among
individual life histories, population dynamics, and community structure in an effort to develop a comprehensive
understanding of reservoir ecosystems. We have used a combination of field collections and modeling to address multiple questions such as:

- the influence of spotted bass introductions and potential hybridization with largemouth bass
- the Influence of white perch introductions on striped bass size, age, and population dynamics
- competitve interactions among catfish
- the effects of multiple invaders on reservoir fish populations using Ecopath with Ecosim
- competitve and predatory interaction of newly stocked striped bass fingerlings
- the contribution of pelagic forage fish to the diets of reservoir predators

Read paper on LMB-SPB hybridization here.

Project Overview:

In North Carolina and elsewhere, there is concern that hypoxia (low DO) due to excessive nutrient loading is adversely
affecting coastal ecosystems, but quantifying the effects on fish and other living resources remains difficult. Our prior work indicated that
indirect effects (e.g., density-dependent reductions in growth and survival as fish crowd into oxygenated refuges) were potentially more
Important than direct effects, because most fish can detect and avoid DO levels that cause mortality or reduced growth. Therefore, if we are to understand
the effects of hypoxia on estuarine fishes we have to evaluate the processes occurring in oxygenated refuges that potentially impact
growth and mortality. Using juvenile spot, Leiostomus xanthurus, a representative estuary-dependent species, we are experimentally determining
the sensitivity and response time of two biological indicators of recent growth (RNA-DNA ratios in muscle tissue, and plasma levels of insulin-
like growth factor I) to changes in environmental conditions, and applying them in the field to assess the effects of hypoxia dynamics on
growth. Our overall goal is to directly link changes in water quality with impacts on fish growth and production in nursery habitats by
quantifying the sublethal effects of hypoxia on juvenile estuary-dependent species.

Project Overview:

Mercury contamination of aquatic foodwebs and fish tissue is a global concern. Currently, a number of consumption advisories have been issued for
common, widely consumed fish species. Because fish are the primary vector for moving mercury from aquatic systems to people, the need
to understand factors that facilitate mercury bioaccumulation and contamination risk is substantial. Our collaborative group is taking
a comprehensive approach to understanding species in systems throughout the state of North Carolina in an effort to better
predict risk of mercury consumption. In particular, we're interested in the range of biotic and abiotic factors that drive mercury
conversion (from elemental mercury to methylmercury, the toxic form) and bioaccumulation. We're also quantifying the influence of
point-source mercury pollution; though mercury is believed to be a global contaminant (due to atmospheric movement), little is known
about the impact of local sources such as coal-fired power plants. Using cutting- edge statistical and analytical approaches,
we hope to produce a more robust understanding of mercury dynamics in aquatic systems, and to work with fishery
managers and human health officials to better communicate relative risk to the public.

See publication on factors influence mercury movement here.
See publication on mercury and selenium risk associated with coal-fired power plants here.

Project Overview:

In this investigation we are interested in learning more about the life history of an understudied,
endemic madtom. This species now exists in only two river drainages in North Carolina, the Tar and the Neuse.
Although little is known about the Carolina madtom, evidence exists that the species is in decline, and it is currently
listed as Threatened in North Carolina. We are investigating habitat use of this madtom in both river drainages in an
effort to determine why it seems to be doing relatively well in the Tar River drainage but continues to decline in the
Neuse River drainage. Working in conjunction with the North Carolina Wildlife Resources Commission and with
funding from a State Wildlife Grant, we will ultimately be able to address issues related to the current distribution,
abundance and habitat requirements of the Carolina madtom. We are also conducting laboratory experiments to
better understand the madtom's use of artificial habitat, which might be used
in efforts to restore the species.

Read paper on Carolina madtom habitat suitability here
Read paper on Carolina madtom spawning habitat here