January 2015 Newsletter
Letter from the Director
Happy New Year!
It was great to meet many of you at our first Research Showcase in November. I'm pleased to report that over 225 people came to the St. Paul Student Center on the University of Minnesota campus for a day-long program of talks and demonstrations featuring MAISRC's ongoing research. Our scientists enjoyed showing you some of the techniques they have pioneered, telling you about their recent research findings, and sharing their ideas about what Minnesota needs to do to thwart AIS. But what made this day especially productive were the contributions of the participants. We're glad we allowed plenty of time for discussion! Your observations, questions, and ideas added so much to every session—many researchers noted that they gained new insights from these exchanges and we suspect it was energizing for many in the audience, too.
The showcase was MAISRC's first opportunity to partner with the Minnesota Extension Service (MES). Thanks to MES staff, especially Susanne Hinrichs (Brainerd), Mardi Harder (Cloquet), Nate Meyer (Cloquet) and Bette Vichorek (Cloquet), who helped with planning, hosting, and arranging transportation for those coming from our northern lake counties. We expect that this event will be the first of many MAISRC programs that we do in partnership with MES. In fact, before the lakes and rivers thaw this spring, we should have a new AIS Extension Educator on board, supported with Center funding, who will spearhead new programs on critical initiatives, such as citizen-based monitoring to help us assess success of various AIS control treatments.
Also in attendance at the Showcase were members of our Research Needs Assessment Team. As I mentioned in our last newsletter, MAISRC established a team of university scientists, agency biologists, AIS mangers from around Minnesota, and national experts to comprehensively evaluate the Center's priorities for future research. The Showcase provided valuable context for our research needs assessment meeting, which was held the following day, on November 20. We received hundreds of research ideas from citizens, managers, and scientists, which were hashed over, organized and refined, and eventually will be distilled into recommendations that will be considered by our center faculty, advisory board and me for next steps. We should be able to share these ideas with you in the next newsletter. I want to thank everyone who submitted research ideas—like at the Showcase, your opinions help our researchers have their fingers on the pulse of Minnesota's AIS challenges.
These two events—the Showcase and our research needs assessment – demonstrate how important it is for MAISRC to be connected to Minnesotans working on AIS challenges. Thanks again for all of your efforts to respond to AIS on your lakes, rivers and wetlands—and for sharing your insights from those experiences with us.
Dr. Susan Galatowitsch
Director, Minnesota Aquatic Invasive Species Research Center
Zebra mussel research finishes first field season
MAISRC researcher Dr. Michael McCartney spent the summer and fall of 2014 collecting samples to support three major areas of zebra mussel research.
First, McCartney collected adult zebra mussel tissues from twelve lakes and three river systems throughout Minnesota. McCartney and his team ensured that collections occurred in all major regions of infestation in the state. Working in conjunction with the University of Minnesota Genomics Center, these tissues will be studied to help identify source populations and the pathways of spread of zebra mussels.
Second, the team collected veligers (microscopic larvae) from multiple locations within ten lakes to help develop molecular methods for early detection. Now, the arduous process (pictured) of counting veligers and preparing them for quantitative molecular testing begins. The samples gathered throughout the summer are very valuable for many reasons: the sheer number of samples, the variation among the lakes sampled with respect to both lake chemistry and plankton communities, and the time period covered by these collections (samples were taken during each month of the reproductive season).
Third, McCartney studied how zebra mussels spread downstream in small rivers. The initial indication is that settlements of juvenile mussels on the stream bottom drops to near zero just a short distance downstream from the source lake. Currently, his lab is counting veliger larvae from samples along these same rivers to examine whether numbers of larvae also decline downstream. In summer 2015, this work will continue on other river systems. All of the results will be used to estimate how many veligers can travel downstream, and how far they can go. These results may help DNR refine the way they designate infested, interconnected waterways.
Looking forward, McCartney's zebra mussel research will focus on understanding pathways of spread to help target prevention efforts as wisely as possible toward lakes with the highest risk of future invasions. This research will be coupled with the development of a rapid water test to detect the presence of veligers, which when contained, may be able to control an infestation before it becomes problematic. Dr. McCartney believes this will become increasingly important as treatment options (e.g. Zequanox and potash) are being explored. Thank you to the Gull Chain of Lakes Association for their support of this research.
Renovation Update: Engineering and Fisheries Lab
Last month, the University of Minnesota Board of Regents approved the schematic designs for the renovations of MAISRC's Engineering and Fisheries Lab. This much-needed capital project will allow MAISRC to further our research projects with zebra mussels, mature Asian carp, pathogens, and invasive plants.
The new state-of-the-art facility will be the only one of its kind and will include a sophisticated water supply system and large tanks for studying adult Asian carp, isolated areas for studying pathogens that might control AIS, and environmental chambers for researching invasive plants. See a sketch of the proposed floor plan.
The current lab – which is held in a century-old tractor garage – is not compatible with MAISRC's goals of providing leading research on aquatic invasive species and preserving the ecological health of Minnesota lakes and rivers. The new lab is anticipated to be complete by the end of 2015. Significant funding for this effort was provided by the Minnesota Legislature in 2014. Stay tuned for further updates on its progress.
Success! Common carp under control in Riley Chain of Lakes
Work in the Riley Purgatory Bluff Watershed District culminated this fall with the exciting announcement that common carp in one of their sub-watersheds, the Riley Chain of Lakes, is under control. Work continues in the other sub-watershed, Purgatory Creek.
Nearly a decade of basic and applied research has gone into this project to understand common carp, a ubiquitous invasive species that infests many lakes, wetlands and rivers across southern and central Minnesota, including the metro area. This long-term project, which required cooperation from numerous partners, worked not just to understand common carp, but to use this knowledge to advance control efforts.
The common carp, which was originally introduced to the U.S. following citizen requests in the 1870s, was seemingly able to take hold due to its high fecundity, low mortality rates, resilience, and ability to exploit productive and degraded waters for reproduction. By uprooting plants and releasing nutrients from sediments, carp further degrade water quality and waterfowl habitat.
Despite the pervasive presence of common carp in Minnesota, it – like all species – has weaknesses. A team of researchers, led by Dr. Peter Sorensen and Dr. Przemek Bajer, has been researching how carp movement and distribution can be used for control.
Through the use of radio-telemetry to track individual fish, researchers found that carp are widely dispersed throughout lakes in the summer and fall, but begin aggregating in mid-December. These aggregations, which appear to be a social behavior, can be targeted with seine nets for removal. Researchers are still unsure how carp determine where to gather; there is no discernible difference in temperature or dissolved oxygen in the area they choose. As evidenced in Lake Riley, seining can be extremely effective: 90% of the carp population was removed this way.
During the winter, researchers use antennae and receivers (pictured) to track fish (known as "Judas fish") that have been implanted with radio-tags. When conditions are appropriate and the fish are densely aggregated, the scientists then work with commercial fisherman to place nets under the ice, surround the fish, and remove them. Carp are highly sensitive to sound and will avoid the nets if targeting is imprecise or too noisy, or if the nets get caught on debris. They also seem to learn to recognize fishers, so the technique must be deployed strategically.
In order for seining to have long-term, sustainable effects on carp and water quality, Sorensen, Bajer, and their colleagues have determined that adult fish removal needs to be part of an integrated approach that also includes biocontrol using native bluegill sunfish that consume carp eggs and larvae, as well as aeration to prevent winterkills and keep bluegills alive. This approach – known as Integrated Pest Management – was developed and implemented for carp on the Riley Chain of Lakes and has successfully kept the carp population under control. It was the early success on that project that inspired the creation of the Minnesota Aquatic Invasive Species Research Center by Sorensen and will help guide future research and management plans for other Minnesota watersheds.
Congratulations to all the researchers and partners who have worked on the project, including the managers and staff of the Riley Purgatory Purgatory Bluff Creek Watershed District, Lake Riley Improvement Association, CH2M Hill Engineering, Barr Engineering, the City of Eden Prairie and private citizens. The Minnesota Environment and Natural Resources Trust Fund and the Riley Purgatory Bluff Creek Watershed District funded this critical work. Stay tuned to our website for more updates as we continue work on common carp in the Purgatory Chain of Lakes in 2015.
Advancing AIS detection technologies
One of the most challenging aspects of managing aquatic invasive organisms is that they are difficult to measure. At times, AIS managers don't even know if these species are present until their populations are large enough to create problems. Dr. Jessica Eichmiller, a post-doctoral researcher working with Dr. Peter Sorensen, is leading the Center's research to develop a method to measure the abundance of invasive carp using environmental DNA (eDNA) – fragments of DNA shed by organisms in water. Using molecular methods to detect eDNA is non-invasive, rapid, and potentially more sensitive than traditional census techniques. As state and federal Asian carp surveillance efforts increase in Minnesota's waters, the Minnesota Aquatic Invasive Species Research Center wants to answer: what does a positive (or negative) detection of eDNA mean?
MAISRC researchers are using common carp as a model species to understand eDNA, for several reasons: carp is abundant in Minnesota, are actively being managed, and have been the focus of previous behavioral and population research by resident scientists, Sorensen and Bajer. Using a sensitive molecular assay specific for common carp mitochondrial DNA, developed by Eichmiller, researchers sampled a lake with a high biomass of common carp. They found that eDNA distribution was extremely patchy and strongly correlated with distribution of fish. This research showed that knowledge of fish behavior, when used to guide eDNA sampling, can greatly improve the probability of species detection. The results of this study were recently published in the online journal Plos One. Read Eichmiller's paper, "The Relationship between the Distribution of Common Carp and Their Environmental DNA in a Small Lake," here.
Understanding how eDNA is distributed in the environment can help researchers design sampling schemes to target eDNA, and will thus improve the reliability of techniques to detect, and then ideally to control, invasive carp.
MAISRC researchers publish new paper
MAISRC researchers Dr. Jessica Eichmiller, Dr. Przemek Bajer, and Dr. Peter Sorensen recently published a new paper, "The Relationship between the Distribution of Common Carp and Their Environmental DNA in a Small Lake."
The paper focuses on developing a method to measure the abundance of invasive carp using eDNA, a detection method which is non-invasive, rapid, and potentially more sensitive than traditional census techniques. As state and federal Asian carp surveillance efforts increase in Minnesota's waters, MAISRC is working to understand how eDNA distribution in the environment can help managers design sampling schemes to target eDNA, and thus improve the reliability of AIS detection techniques. Read the paper online here to learn more.
Showcase presentations now available online
Thank you to everyone who attended November's Minnesota Aquatic Invasive Species Research and Management Showcase! Over 225 people joined us on the St. Paul campus to hear firsthand from MAISRC scientists and guest speakers about their research, check out our labs and facilities, and gain skills to work on AIS issues in their communities. If you were unable to attend in person or would like more information about what was covered, many of the presentations are available on our website. From tips to identify Eurasian water milfoil to evaluating the effectiveness of AIS management, a lot was discussed at the Showcase – so learn more today.
Join us at the 2015 Aquatic Invaders Summit
Join the Minnesota Association of Watershed Districts and the Initiative Foundation in St. Cloud for the 2015 Aquatic Invaders Summit on January 20th and 21st! The Summit is being held with the goal of bringing together Minnesota local governments and their partners to work together to limit and prevent the spread of Aquatic Invasive Species. Two MAISRC researchers – Dr. Peter Sorensen and Dr. Michael McCartney – will be presenting. Register today!
Thank you to the Gull Chain of Lakes Association
Everyone at MAISRC would like to extend a huge thank you to the Gull Chain of Lakes Association (GCOLA) for their extremely generous recent gift of $25,000 to support the Center's research. Given the threats within the chain of lakes, GCOLA is particularly interested in the Center's efforts on prevention and control of zebra mussels and Eurasian water milfoil. This is the second gift of $25,000 made by GCOLA to MAISRC.
The Gull Chain of Lakes Association is an alliance of watershed property interests within the Gull Chain of Lakes in Cass and Crow Wing Counties. They are devoted to the restoration and continued preservation of the highest water quality and environmental standards achievable, promotion of the responsible use of land and water resources, and recreational safety on the Gull chain of lakes. Their primary responsibilities include educating members about best management practices to improve water quality, water safety, and prevent the spread of aquatic invasive species.
When presenting their gift, Gull Chain of Lakes Association board chairman Uldis Birznieks said, "We are pleased to continue to support the promising work that MAISRC is doing with regard to zebra mussels, Eurasian water milfoil, and more. As an alliance of conscientious lake users, we feel a responsibility to support this research to the best of our ability. We hope to serve as a model for other lake associations who share our goal of finding innovative solutions to Minnesota's AIS problems."