Loyola University Chicago

Department of Biology

Conrad S. Zack Project Description

Title: Chironomidae (Diptera) Community Structure in Lakes of Contrasting Morphometry, Landscape Position, and Water Chemistry


Chironomidae (Diptera) surface-floating pupal exuviae were collected monthly during the ice-free season in 2010-2011 from six lakes in the North Temperate Lakes Long-Term Ecological Research site in northern Wisconsin.  The goal of this study was to determine whether chironomid community structure reflected differences in lake morphometry (i.e. depth, area, shoreline development, etc.), landscape position, and/or water chemistry.  Forty-six genera were identified from four subfamilies:  Chironominae (57%), Orthocladiinae (28%), Tanypodinae (11%), and Diamesinae (4%).  Tanytarsus, Ablabesmyia, and Psectrocladius were found in all six study lakes; whereas certain genera, such as Omisus, Protanypus, and Epoicocladius were each observed in only one lake.  An analysis of abiotic variables revealed that pH, Secchi depth, and total phosphorus were the most important factors structuring chironomid communities in the NTL-LTER clearwater study lakes, but a more complete suite of habitat variables that includes biotic factors (i.e., algal growth and availability and macrophyte characteristics) should be sampled in future studies to determine the importance of these variables.  Elucidating the factors that influence chironomid community structure can lead to an improved understanding of chironomid ecology and distribution patterns in north temperate lakes and will be a valuable asset in examining the interplay of landscape position and biological communities in lakes



 I would like to thank Loyola University Chicago, Department of Biology for accepting me as a graduate student in 2009 and providing funding for my pursuit of a Master’s degree.  Thank you to the Department of Biology office staff and faculty who all have been encouraging and supportive as I worked through the graduate research program.  A debt of gratitude goes to Pam Fashingbauer, Dr. Tim K. Kratz, Aaron Stephenson, Dr. Emily H. Stanley, and all other staff that I crossed paths with at Trout Lake Station in the North Temperate Lakes Long-Term Research site during my research field seasons.  Without their assistance and knowledge this project would not have been completed.  I would like to thank my thesis director, Dr. Martin B. Berg, for his advisement, vast knowledge of the Chironomidae, encouragement, bourbon and beer recommendations, and most importantly, patience.  I could not have asked to work with a better scientist and person, especially during the times of doubt.  Thank you for sharing your knowledge, sense of humor, and believing in me during this journey; I am truly honored to be known as one of your graduate students.  I have experienced your well-known red penned comments over multiple drafts of my thesis and have come out a better aquatic biologist and person.  Thank you to my thesis committee members, Drs. Sushma Reddy, Joseph Milanovich and Leonard Ferrington for their insight and helpful comments on my research.  My committee probably thought I disappeared, but I was around moving slowly towards the finish line. 

Shout out goes to Chantel Adelfio and Nick Furlan for their friendship that developed over the years and will last a lifetime. The Berg Lab would not have been the same without them and I am very lucky they are both in my life.  Thank you to the staff at EA Engineering, Science, and Technology, Inc., PBC for supporting this effort and allowing my position to remain as I worked on my thesis research.  I would be remiss if I did not thank all the people I met through the New Mexico Department of Game and Fish that introduced me to aquatic biology and field work. I have no clue what I would be doing today if I did not accept a summer conservation technician position back in 2003. Special thanks to Dave Propst, Bob Larson, Stephanie Carman, and Amber Kingsbury for showing me the beauty of the rivers in New Mexico and teaching me about the life in them.

My thesis project would not have been completed without the support, poking and prodding, and encouragement from my wife, Sarah Zack. I know at times the process was frustrating, but thank you for sticking with me to reach my goal.  Lastly, thank you to my dad, mom, and brother who will no longer ask, “When will you be done?!?”



Conrad S. Zack graduated from the University of New Mexico in 2003 with a Bachelor of Science degree in Biology.  As an undergraduate, he had a scientific article published in Wildlife Society Bulletin about the southern oscillation index and encounters between humans and black bears in New Mexico.  After graduation, he worked for the New Mexico Department of Game and Fish (NMDGF) in the Conservation Services Division – Endangered Species Program in Santa Fe where he was introduced to and developed an interest in aquatic biology.  Following the position with NMDGF, in 2005, Conrad moved to Chicago, IL and found employment with EA Engineering, Science, and Technology Inc., PBC., an environmental consulting firm in Deerfield, IL.  During this position, he solidified his love of aquatic biota and refined his aquatic macroinvertebrate taxonomy skills ,becoming a Certified Taxonomist in General, EPT, and Chironomidae – eastern taxa in 2013 by the Society for Freshwater Science.  He also has advanced his ichthyoplankton taxonomy skills since 2005 working with well known experts Darrel Snyder, Robert (Bob) Wallus, and Larry K. Kay.  He has been with the company for 12 years and currently works as an Aquatic Biologist/Benthic Macroinvertebrate and Larval Fish Taxonomist.


Committee Members

Dr. Martin B. Berg

 Dr. Sushma Reddy

 Dr. Joseph Milanovich

 Dr. Leonard Ferrington – University of Minnesota