My research has focused on factors affecting population and community dynamics of freshwater fish and invertebrates, especially the role of disturbance in community dynamics, impacts of introduced species in aquatic ecosystems, and aquatic ecosystem conservation. My recent research includes studying, 1) classification of Arkansas flow regimes and developing ecological-flow response relationships and environmental flows assessment for the Ozark region, 2) factors affecting distribution and abundance of the endangered yellowcheek darter, 3) distribution, population genetics and factors affecting imperiled coldwater crayfish, 4) effects of drought and episodic drying on stream fish and invertebrate population and community dynamics, 5) effects of stream drying on fish and invertebrate refuge use and species persistence, 6) models to forecast effects of potential climate change scenarios on fish refuge use and species persistence, 7) influence of drying on fish and crayfish consumers and how they in turn affect stream ecosystem structure and function, 8) the relationship between land use, flow regime, habitat complexity and fish assemblage structure, 9) the potential spread of invasive species and mechanisms of displacement on native species, 10) the influence of abiotic and biotic factors on habitat selection by stream fish and crayfish, and 11) the effect of catch and release areas on movement and mortality of resident rainbow and brown trout in cold tailwater rivers and the relationship between forage base and trout production in these special regulation areas. As part of this work, I attempt to bridge the gap between studies done at small spatial scales and the larger spatial scales necessary to understand how disturbance and movement affect population and community dynamics in stream ecosystems. These projects and related work are carried out using a combination of observation, experimentation in the field and lab, and modeling approaches.
Fisheries ecology, aquatic ecology, conservation biology
Dekar, M.P. and D.D. Magoulick. 2013. Effects of predators on fish and crayfish survival in intermittent streams. Southeastern Naturalist 12:197-208.
Westhoff, J.T., R.J. DiStefano and D.D. Magoulick. 2012. Do environmental changes or juvenile competition act as mechanisms of species displacement in crayfishes? Hydrobiologia 683:43-51.
Hodges, S.W. and D.D. Magoulick. 2011. Refuge habitats for fishes during seasonal drying in an intermittent stream: movement, survival and abundance of three minnow species. Aquatic Sciences 73:513-522.
Larson, E.R. and D.D. Magoulick. 2011. Life history notes on Cambarus hubbsi (Hubbs Crayfish) from the South Fork Spring River, Arkansas. Southeastern Naturalist 10:121-132.
Dekar, M.P., D.D. Magoulick and J. Beringer. 2010. Bioenergetics assessment of fish and crayfish consumption by otter (Lontra canadensis): integrating prey availability, diet, and field metabolic rate. Canadian Journal of Fisheries and Aquatic Sciences 67:1439-1448.
Ludlam, J.P. and D.D. Magoulick. 2010. Effects of consumer identity and disturbance on stream mesocosm structure and function. Fundamental and Applied Limnology 177:143-149.
Ludlam, J.P. and D.D. Magoulick. 2010. Environmental conditions and biotic interactions influence ecosystem structure and function in a drying stream. Hydrobiologia 644:127-137.