August 2016 AIS Spotlight
Letter from the Director
There are few moments in life where opportunity and preparedness (a.k.a. ‘luck’) perfectly align. For me, this happened last month when I teamed up with Dr. Susan Galatowitsch to become Co-Directors of MAISRC. For one year, Sue will continue to oversee existing projects to ensure a productive and stable transition. I thank her, MAISRC founder Dr. Peter Sorensen, the Minnesota Environment and Natural Resources Trust Fund, the Department of Natural Resources, and all of the many, many stakeholders who have positioned MAISRC to be an innovative and collaborative leader in the field of aquatic invasive species research. I am excited to build on this foundation to find research-based solutions to AIS problems in Minnesota.
I get it. I grew up on the lakes in northern Minnesota and know firsthand the issues our lakes and rivers face, and the challenges that must be overcome. So much so, that I have dedicated my education and career to do what I can to protect them. I am by no means alone and am humbled to work with an incredible team of ~40 researchers affiliated with MAISRC. We are working tirelessly to find solutions, but are faced with the reality that quality research can take time. However, there are many reasons to be optimistic: our work is already filling key knowledge gaps for decision-making and making an impact on the prevention, control, and management of AIS in Minnesota.
What might that be, you ask? Come to our 2016 Research Showcase to find out!
No other time of year will all the MAISRC researchers be in one place and available to you. Listen to their latest research findings, plans for future work, and ask questions. Have lunch or a drink during the social with them. Provide input into our current research needs assessment. Hear from the DNR Commissioner Tom Landwehr and UMN CFANS Dean Brian Buhr. See the newly renovated state-of-the-art and one-of-a-kind research lab. Network with fellow AIS stakeholders from across the state. I could go on, but a long story short – I hope to see you there.
Time to get back to the lab…
Dr. Nick Phelps
Selectively controlling carp using biotoxins
An innovative new project at MAISRC is adding new tools to the toolbox for common carp control: the selective use of toxins, and using bluegills as biocontrol. This research will complement and enhance control options already researched at MAISRC, including winter seining and aeration combined with barriers.
In partnership with the USGS’s Upper Midwest Environmental Sciences Center, MAISRC researchers are developing and testing a unique toxicant to kill the invasive fish.
Because the toxin, antimycin-a, is lethal to most fish, researchers must determine a highly species-specific method of delivery. Unlike native fish, carp are attracted to corn – leading researchers to formulate toxic corn pellets. Carp can also be trained to aggregate in baited areas by feeding them, and after sufficient training, researchers can switch out the regular corn pellets for toxic pellets and kill the carp.
In addition to testing the toxin on native fish such as perch and sunfish to ensure they are not harmed, researchers will be determining the lethal concentration required and the amount of time that elapses before the carp die.
“Antimycin-a is already approved as a piscicide, and we know it can be used to kill fish,” said Dr. Przemek Bajer. “The unique – and critical – part here is that we are figuring out how to ensure it only harms invasive common carp and no native species.”
And for the first time in whole-lake experiments with natural lake processes at play, this project will also test whether bluegills can be used as a biocontrol agent for common carp. By consuming their eggs and larvae, bluegills can reduce common carp populations. They also do well in hypereutrophic lakes, an environment in which carp typically thrive. Having a better understanding of bluegill-carp interactions in both high- and low-nutrient lakes could eventually result in a set of variables that would determine whether sunfish could be used for control in a specific lake.
Read more about common carp research at MAISRC here, and learn more about this from researchers Przemek Bajer and Josh Poole at the 2016 Aquatic Invasive Species Research and Management Showcase.
New MAISRC research to determine long-term impacts of spiny waterflea
This summer, MAISRC launched a new research project aimed at determining the threat that spiny waterflea pose to the structure and function of food webs in Minnesota lakes. Currently, little is known about how exactly the invasive invertebrate changes a lake’s ecology and how much, if any, time passes before changes appear in an invaded ecosystem.
“Using lake sediment data, we’ve learned that spiny waterflea arrived in the Duluth area about eight years before they were detected,” said lead researcher Donn Branstrator. “That means that there’s a lot we don’t know about how their establishment and proliferation translates into impacts on food webs and game fish.”
Researchers will use lake sediment data to reconstruct long-term environmental histories of four lakes – two that have been invaded by spiny waterflea, and two that have not – and compare the long-term historical trends in key components of the food webs.
“Determining the types, magnitude, and timing of changes that occur to lakes after spiny waterflea invade will help give managers a more clear idea about the sense of urgency, the magnitude of the problem, and the lag time associated with an invasion,” added Branstrator. “It will also help us understand and define the threats this organism poses to sport fishing and water quality.”
Spiny waterfleas (Bythotrephes longimanus) are a microscopic freshwater zooplankton. They disturb the food web by consuming native Daphnia and can clog the eyelets of fishing rods. They have fewer predators than native zooplankton because small fish can’t consume their sharp, barbed spine.
Learn more about spiny waterfleas on our website and hear from Donn Branstrator about this research at the 2016 Aquatic Invasive Species Research and Management Showcase on September 12 – registration now open!
Saving our lakes, one tiny weevil at a time
If you paddle or swim on Cedar Lake in Minneapolis, you may have noticed this unusual sight: three large, black rings floating on top of the water.
These enclosures are serving as a temporary research lab for Dr. Ray Newman and his team as they study the effect that the tiny milfoil weevil has on invasive Eurasian watermilfoil. Each enclosure was stocked with a different number of sunfish, which eat the native weevils, which in turn eat the milfoil. Researchers will study the changes in milfoil density as summer progresses.
Learn more about this unique approach to the biocontrol of aquatic invasive species by watching this great video from Kare11!
Eurasian watermilfoil forms thick mats on the surface of the water which shade out native plants and makes swimming and boating difficult. Learn more about this research on our website, and hear from lead researcher Ray Newman about this work – including a peek at actual weevils in our newly renovated lab! – at the 2016 Aquatic Invasive Species Research and Management Showcase on September 12.
In the fight against Asian carp, a new weapon: pathogens
MAISRC researchers Sunil Mor and Nick Phelps have collected and examined samples of Common, Bighead, and Silver carp from Minnesota and Illinois. These samples were screened to determine the virome –the picture of all the viruses that inhabit a particular organism – in order to identify any unique opportunities for control.
Using a genome sequencing technique called Illumina MiSeq, researchers identified two novel viruses from common carp and grass carp mortality events: novel picornavirus and novel paramyxovirus. Additionally, they identified the first report of Grass Carp Reovirus (GCRV) associated with fish mortality in the United States. Divergent picornaviruses, reovirus, hepevirus and nodavirus were also detected in Common carp, and hepevirus was detected in the Silver carp samples.
Establishing and understanding what novel viruses are circulating in invasive carp will provide important baseline information in order to select a species-specific pathogen that could be introduced or promoted to act as a biocontrol.
The concept of using viruses as a biocontrol is gaining popularity throughout the world, most recently in Australia where Koi Herpes Virus is being considered for common carp control. This research is proceeding with a high level of caution since protecting native species and promoting ecosystem health is a top priority for MAISRC. Learn more about Asian carp research here and hear from lead researcher Sunil Kumar Mor at the 2016 Aquatic Invasive Species Research and Management Showcase.
Register today for the 2016 Minnesota Aquatic Invasive Species Research and Management Showcase
If you have been wondering what is known about starry stonewort impacts and spread, what is the status of research on spiny waterflea, if new infestations of zebra mussels be eradicated, or if we should be worried about Heterosporis, then this event is for you!
Two new papers from MAISRC researchers
Researchers Dr. Ratna Ghosal, Peter Xiong, and Dr. Peter Sorensen recently published a paper entitled “Invasive Bighead and Silver Carps Form Different Sized Shoals that Readily Intermix.” The paper discusses how Asian carp form tight groups (shoals), a strategy that helps individuals find food and avoid predation. This may explain why they are hard to find and catch in low densities.
Researchers Luis Escobar, Nick Phelps, Dan Larkin, and Carli Wagner recently published a paper “Realized niche shift associated with the Eurasian charophyte Nitellopsis obtusa becoming invasive in North America.” The paper discusses using ecological niche modeling to predict suitable habitat for the invasive algae starry stonewort.
Farewell and thank you to researchers Jessica Eichmiller and Nate Banet
MAISRC is saddened to bid farewell to research associate Jessica Eichmiller, and thank her for her countless contributions to the fight against aquatic invasive species. But, we’re excited to congratulate her on her new position as a biology instructor at Alexandria Technical & Community College! Dr. Eichmiller specialized in using eDNA methods to quantify fish biomass and published several papers on the topic while at MAISRC.
Congratulations to Nate Banet for successfully defending his master's thesis: Partial migration, homing, and distribution of adult common carp across a large, model watershed in the North American Midwest. Nate’s research on the movement patterns of common carp helps explain the success and invasiveness of common carp while also improving targeted removal efforts.
Best wishes, both!
Increasing capacity for invasive aquatic plants research
MAISRC is pleased to welcome two new researchers to its team: graduate student Mike Verhoeven and lab technician Wes Glisson. Both are working on Dr. Dan Larkin’s team, researching the effects that invasive aquatic plants have on native ecosystems and examining the mechanisms of their reproduction and colonization.
Join MAISRC at the 2016 Aquatic Invaders Summit
Several MAISRC researchers – including Nick Phelps, Peter Sorensen, Dan Larkin, and Mike McCartney – will be presenting at the Aquatic Invaders Summit on October 5-6 in St. Cloud. Learn more about the event here.
Everyone at the Minnesota Aquatic Invasive Species Research Center would like to thank the Pelican Lake Association of Crow Wing County for their generous support of our research three years in a row!
You can lend your support to MAISRC's solutions-oriented work by donating today. Private donations truly make a difference to our work and provide us with the flexibility to meet critical needs as they arise. Thank you!