I am Assistant Unit Leader at the Arkansas Cooperative Fish & Wildlife Research Unit and Professor in the Department of Biological Sciences at the University of Arkansas. 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, aquatic ecosystem conservation and trophic dynamics. 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 natural and human impacts affect population and community dynamics in stream ecosystems. These projects and related work are carried out using a combination of comparative studies, manipulative field and lab experiments, and modeling approaches.
Prospective Students
I am regularly interested in taking on graduate students. Contact me using the link above or at danmag@uark.edu.
Environmental thresholds Research
We are examining the influence of hydrology, climate and other environmental factors on fish and insect population and community dynamics.
Conservation Biology Research
We are conducting multiple research projects examining factors influencing species of conservation concern, including endangered species.
Current Research Projects
These are just two of several ongoing projects in the lab.
News
Josh Tivin and Dan published an article titled "Seasonal and hydrologic variation influences habitat structure and functional composition of stream fish assemblages" in Frontiers in Environmental Science.
March 2026
Congratulations to Kearstin Findley for winning the Best Student Poster Award at the Southern Division American Fisheries Society conference in New Orleans!
March 2026
Jon Flinders and Dan published an article titled "Assimilation efficiency of rainbow trout fed natural diets" in Environmental Biology of Fishes.
Jan 2026
Jon Flinders, Ashley Clement and Dan published an article titled "Effects of prey and tissue type on δ13C and δ15N discrimination and turnover rates of rainbow trout" in Hydrobiologia.
Jan 2026
Sarah Sorensen joined our group as a postdoctoral fellow. Sarah completed her PhD at University of Arkansas and spent a year as a postdoc at University of Wyoming.
Jan 2026
Leah Bayer and Dan published an article titled "Native crayfish shows high desiccation tolerance and potential to outcompete invader" in Biological Invasions.
Sept 2025
Gavin Saenz joined our group as a MS student. Gavin completed his BS at Texas Tech University.
Aug 2025
Sarah Sorensen and Dan published an article titled "Disturbance is primary determinant of food chain length when top predator is constant".
Aug 2025
Dan and Christy Graham published an article titled "Relationships between larval fish drift, time of day and discharge in an Ozark stream".
May 2025
Dan finished teaching Conservation Biology for Spring 2025.
May 2025
About Our Lab
I work with post-docs, graduate and undergraduate students, and technicians in a team doing basic and applied research to address conservation and ecological questions. I currently have a Post-Doctoral Fellow, four PhD students, one MS student and a technician working with me. Much of our work takes place in the Interior Highlands, but we have also worked in other regions of the US as well as internationally..
