Sally Entrekin (Lab page)
Aquatic Ecology Lab
University of Central Arkansas                                                                    
phone:501-450-5919 fax: 501-450-5919

2011 Lab members
Entrekin Lab
Top row (left to right): Jordan Johnson, Will Maurer, Josh Bregy, Adam Musto, Chris Fuller
Bottom Row (left to right): Allyn Fuell, Nicki Jensen, Julie Kelso, Mandy Bates, Sally Entrekin
Not pictured: Chelsea Miller, Ali McLeod, and Daniel Sniegowski


Ecology of streams and wetlands

Most of our research focuses on changes in invertebrate community structure, production, and food web composition following natural or anthropogenic disturbances.  For example, I quantified changes in macroinvertebrate production following the experimental addition of large wood to streams in forested, yet intensively managed, watersheds.  My work generally aims to determine changes in ecosystem processes, such as invertebrate production or decomposition, following changes in landuse. One of our main projects is quantifying biological effects of natural gas development on intermittent streams.  Arkansas has a lot of intermittent and ephemeral streams and wetlands and so much of our research is currently exploring biological consequences of variable hydrology coupled with anthropogenic alterations.


Current Projects


          rice fields            wetland                      
Graduate students

Allyn Fuell  earned her Bachelor of Science degree in Biology from Lyon College, where she did undergraduate research in the Lindblom lab on the involvement of nhr-8, an orphan nuclear hormone receptor, in xenobiotic metabolism in the soil nematode C. elegansAllyn’s thesis research is part of a multi-agency collaborative effort gathering data to inform the development of a Wetland Management Plan for White Oak Bayou watershed in Pulaski County, Arkansas. Her primary research objective is to quantify the mechanisms driving differences in leaf decomposition rates in the two dominant wetland types in the watershed. She has been involved with hydrogeomorphic (HGM) wetland assessment throughout White Oak Bayou, and is using data gained from these assessments to evaluate the utility of HGM as a predictor of wetland ecosystem function, particularly nutrient cycling. She is also investigating land use effects on leaf decomposition rates in the watershed.

Nicki Jensen completed her undergraduate degree at the University of Arkansas-Fayetteville with a B.S. in Biology. While and undergraduate, she worked with Dr. Michelle Evans-White on a stream flood study, a rapid bioassessment of the Upper White River Basin project, and conducted her own research on a stream restoration. She is currently working on the Fayetteville Gas Shale Project to determine changes in macroinvertebrate community structure in watersheds that have recently experienced rapid development of natural gas wells.

Julie Kelso graduated from Tulane University with a B.A. in Environmental Policy.  After graduating she spent three years working as a biological technician on a variety of projects ranging from noxious weed inventory in Idaho to banding migratory birds in Virginia.  She always wanted to conduct research in small streams and now studies macroinvertebrate communities in intermittent streams of Arkansas.  Her thesis will explore how macroinvertebrates may use refuge (e.g. the hyporheic) to persist through periods of stream drying.  


Chris Fuller completed his undergraduate degree at University of Central Arkansas with a B.S. in Biology. As an undergraduate, he worked with Dr. Sally Entrekin on the invertebrate community structure of an agricultural watershead in the Lower Mississippi River Valley. He also aided in the identification of chironomid larvae for Dr. Michelle Evans-White from the University of Arkansas-Fayetteville. He is currently working in collaboration with Dr. Entrekin and Dr. Evans-White on an NSF grant to examine how the elmental composition of food resources influences invertebrate (specifically chironomid) growth.

Amanda Bates received her B.S. in biology from the University of Arkansas in 2010. Her master's research focuses on how hydrology of headwater streams affects macroinvertebrate communtiies and leaf decomposition with an emphasis on the funcational role of crayfish. She is working in ephemeral streams in the Sylamore Ranger District of the Ozark National Forest.

Research Technician

Jordon Johnson: graduate from University of Arkansas-Moticello with a BA in Wildlife Management. He is currently working to identify invertebrates from a restoration project and managing the data.

Undergraduate students

Chelsea Miller: Macroinvertebrate diversity in the South Fork Little Red River, AR

Ali McLeod: metabolism in temporary pools in Ozark streams.

Josh Bregy: studies the ecology of wetlands in the Arkansas River Valley.

Daniel Sniegowski: Invertebrate colonization dynamics before and after a stream restoration.

Will Maurer: Macroinvertebrates in the Middle Fork Saline River before restoration.

Former graduate students

David Mitchell, Instructor, Ozarka College, Mountain View, Arkansas

Former undergraduate students

Kasey Nix: Leaf litter decomposition in intermittent Ozark streams.

Phuong Ngyugen: Seasonal changes in nutrient concentrations in ephemeral streams.

Tyler Troutman: Sediment export in streams with varying gas well densities.
Michael Lowry: Leaf litter breakdown in streams with varying gas well densities.

Chris Fuller: Invertebrate community structure in an agricultural watershed in the Lower Mississippi River Valley.
Lindsay Martindale: GIS analysis of stream catchments with varying gas well densities.

Adam Musto: Effects of turbidity on Hyallela azteca.

Professional Organizations

North American Benthological Society (
American Society of Limnology and Oceanography (
Ecological Society of America (


Entrekin, S.A., Evans-White,, M. Johnson, B., Hagenbuch, E. 2011. Rapid expansion of natural gas development poses a threat to surface waters. Frontiers in Ecology and the Environment 9 (9): 503-511. 

Hoellein, T.J., J.L. Tank, E.J. Rosi-Marshall, and S.A. Entrekin. Early View. Effects of benthic restoration on nutrient uptake and ecosystem metabolism in three headwater streams. River Research and Applications.

Jennifer Tank, Emma Rosi-Marshall, Natalie Griffiths, Sally Entrekin, and Mia Stephen.  2010.  A review of allochthonous organic
matter dynamics and metabolism in streams.  Journal of the North American Benthological Society 29(1): 118-146.

Entrekin, S.A., G.A. Lamberti, J.L. Tank, T.J. Hoellein, and E.L. Rosi-Marshall. 2009. Large wood restorations
increase macroinvertebrate secondary production in 3 forested headwater streams.  Freshwater Biology 54: 1741-1748.

Hoellein, T.J., J.L. Tank, E.J. Rosi-Marshall, and S.A. Entrekin. 2009.  Temporal variation in substratum-specific rates of N uptake and metabolism and their relative contribution at the reach scale.  Journal of the North American Benthological Society 28(2): 305-318.

Entrekin S.A., Tank, J.L., Rosi-Marshall E.J., Hoellein T.J., and Lamberti G.A. 2008. Responses in organic matter accumulation and processing 
to an experimental wood addition in three headwater streams.  Freshwater Biology 53:1642-1657.

Entrekin, S.A., E.J. Rosi-Marshall, J.L. Tank, Hoellein, T., and G.A. Lamberti.  2007.  Macroinvertebrate secondary production in forested sand-bottom streams of the Upper MidwestJournal of the North American Benthological Society 26 (3):472-490.

Entrekin, S.A., J.B. Wallace, and S.L. Eggert. 2007. The response of chironomids (Diptera) to a long-term exclusion of terrestrial organic matter.  Hydrobiologia 575:401-413.

M.J. Winterbourn, W.L. Chadderton, S.A. Entrekin, J.S. Harding and J.L. Tank. 2007.  Distribution and dispersal of adult stream insects 
in a heterogeneous montane environment. Fundamental and Applied Ecology 168/2: 127-135.

Hoellein, T.J., J.L. Tank, E.J. Rosi-Marshall, S.A. Entrekin, and G.A. Lamberti. 2007. Controls on spatial and temporal variation of nutrient 
uptake in three headwater streams in the Upper Peninsula of Michigan. Limnology & Oceanography 52(5).

Entrekin, S.A., S.W. Golladay, D.P. Batzer. 2001. The influence of plant community on chironomid secondary production in two wetland types: 
cypress-gum swamps and grass-sedge marshes.  Archiv für Hydrobiologie 152 (3): 369-394.

Golladay, S.W., K.Watt, S. Entrekin, and J.Battle. 2000.  Hydrologic and geomorphic controls on suspended particulate organic concentrations in Ichawaynochaway Creek, Georgia, USA. Archiv für Hydrobiologie 149: 655-678.

Entrekin, S.A., S.W. Golladay, M. Ruhlman, and C. Hedman.  1999.  Unique steephead stream segments in southwest GA: invertebrate biodiversity and biomonitoring. 295-298. In K. Hatcher (editor).   Proceedings of the Georgia Water Resources Conference, Athens, GA.

Golladay, S.W., S. Entrekin, and B. Taylor.  1999.  Forested Limesink Wetlands in southwest GA: Habitat use and hydrologic variation. 197-216. In: D.P. Batzer, R.B. Radar, and S.A. Wissinger (eds). Invertebrates of Freshwater Wetlands of North America: Ecology and Management.  John Wiley and Sons.

Golladay, S.W., K. Watt, S. Entrekin, and J. Battle.  1999.  Hydrologic and geomorphic controls on particulate concentrations in Ichawaynochaway Creek, a Blackwater Coastal plain stream.  In: K. Hatcher (editor).  Proceedings of the Georgia Water Resources Conference, Athens, GA.