May 2017 Newsletter
Letter from the Director
Hello from MAISRC!
It seems we’ve finally made it to spring! As you prepare to open your cabin or make your plans for fishing opener, I want to bring to your attention a recent op-ed I co-wrote with Jeff Forester of Minnesota Lakes and Rivers Advocates for MinnPost.
My points in this article – that although AIS may seem overwhelming, we can’t give up – are central to my belief system and to my leadership at MAISRC. I truly believe that we do not have to accept a future for our children and grandchildren defined by unchecked AIS spread. We do not have to accept destroyed health and biodiversity of aquatic ecosystems, impaired water quality, threatened native species, and impeded access for recreational use. We do not have to pass on a water legacy of negative economic impacts to businesses, tourism, property values, and in turn, the local tax base. We can learn from past success stories and advance scientific innovation to better prevent, control and manage AIS in Minnesota.
The first and biggest hurdle, the one upon which all success ultimately depends, however, is our mindset.
We must set success as our unified goal and give up the notion that there is nothing that can be done. Conceding defeat ensures one inevitable outcome: AIS will continue to spread, establish and degrade our lakes, rivers, and wetlands – likely at an increasing rate.
I am not naïve to the seemingly insurmountable challenges posed by AIS and work every day to address them. I know that solutions will not be easy, fast or cheap. However, I am hopeful for many reasons and believe that if anyone, at any time, could move forward to solve AIS problems, it is Minnesota right now.
Check out the rest of the op-ed here, and I encourage you to remain determined to help solve the AIS issues facing our state.
Time to get back to the lab…
Dr. Nick Phelps
Co-Director, Minnesota Aquatic Invasive Species Research Center
Genetic research fills out map of zebra mussels’ spread in Minnesota
New research findings from MAISRC are filling in the map of zebra mussel spread in Minnesota. These are helping us understand how many mussels it takes to establish a new population in a lake and have revealed that suspected “super-spreader” lakes have not spread mussels throughout the state—a major surprise.
By genotyping and analyzing thousands of zebra mussels in partnership with the University of Minnesota Genomics Center, researchers have found high genetic diversity in lakes. This means that lakes are being colonized by large numbers of mussels or larvae – either from several independent introductions, or through one or few introduction events of numerous mussels.
Researchers also found genetic clusters of zebra mussels that identified regional patterns of spread. The regions of Detroit Lakes, Alexandria, and Brainerd Lakes each have populations that are genetically unique, found nowhere else in the state. Lakes are closely linked, genetically, within each of these regions.
“These genetic clusters show us that lakes are most likely to be infested from other nearby lakes,” said Dr. Mike McCartney. “Therefore, identifying and blocking regional spread vectors should receive closer attention.”
Using these genetic data, researchers were also able to determine that lakes which had previously been considered “super-spreaders” – Mille Lacs and Prior Lake – have not infested other lakes. Their super-spreader status has been inferred due to high boater traffic. The discord between boater movements and genetics tells us that watercraft inspection and decontamination efforts have been effective on Mille Lacs and should be continued — on these and other high-traffic lakes.
“To explain our results regarding Mille Lacs, we’ve concluded that prevention efforts on boats leaving the lake must be working, so that’s satisfying” added Dr. McCartney. “But major questions remain, such as what are the sources for newly infested lakes in Minnesota? As we make more progress with genetic and genomics tools, we plan to answer this question, and directly pinpoint invasion sources and determine routes.”
Promising new acoustic deterrent system being tested in the lab on invasive carp and native fishes
The Sorensen lab at MAISRC is testing a new deterrent system on bigheaded and common carp to identify a set of sensory stimuli that could effectively deter a large number of invasive carp in rivers, without effecting native fish. Thanks to carps’ especially sensitive sense of hearing, sound stimuli are of great interest, but the possibility that other stimuli including air curtains and lights might be synergistic is also being considered. To be useful in navigation locks, deterrent stimuli will have to be highly effective over time and with repeated exposures, as well as safe and species-specific.
An experimental deterrent system has been assembled and is now being tested in the newly renovated MAISRC laboratory. The Sorensen team has already evaluated several types of sound stimuli and found a chirping signal originally identified by an English company to be exceptionally effective for carps, even with repeated exposure. Current research seeks to evaluate species-specificity and enhance deterrence by adding in additional stimuli. This new sound deterrent system could be deployed in navigation locks along with the option of optimizing water velocity through lock and dam spillway gates. Ongoing numeric modeling of water flows though locks and dams also show it to have great promise to stop carp without causing additional scour at lock and dams 2, 4, 5, and 8.
In addition to testing whether this sound system deters invasive carps, this project will test how these acoustic stimuli might impact native fish movement. Bigheaded carp have an exceptional sense of hearing compared to many native species, such as lake sturgeon and walleye, so minimal impacts are expected. The importance of native fishes is addressed by a recently completed invasive carp risk assessment, which urged caution when considering possible prevention and control measures.
This deterrent system adds another piece to the puzzle of invasive carp control, with the overarching goal of producing a sustainable prevention strategy that also promotes the well-being of native ecosystems and fishes in the Misississippi River. Learn more about invasive carps and our research on detecting, preventing, and controlling them here.
Go underwater with MAISRC
For MAISRC, this month marked the return of open water and the beginning of another field season. Researchers are now out at lakes across the metro area examining the differences between invasive Eurasian watermilfoil, native northern watermilfoil, and hybrid watermilfoil – a cross between the two species which is also considered invasive – in order to gain insight for prioritization and control of these invasives.
Researchers will use a unique sampling device to lower a camera into the water in order to count plant stems at different depths below the water and measure plant heights – check out a video of the underwater camera in action here! They will also record key points in plants’ life cycles, including topping out on the surface, flowering, and senescence. Learning this will help researchers understand how big of a threat this hybrid is and how differences in its growth habits will open up opportunities for control.
“You can't have a rational, science-based approach to management if you don't understand the threat,” added Dr. Larkin. “If we learn that the hybrid is a highly invasive super-milfoil, that has different implications for prioritizing control than if it's a weaker version of Eurasian watermilfoil that happens to be more herbicide tolerant.”
Experimental studies of hybrid watermilfoil have shown greater tolerance of commonly used herbicides by some genotypes. There have also been anecdotal and lab-based reports of increased invasiveness in hybrid watermilfoil. However, context is everything. By systematically comparing the behavior of parent and hybrid watermilfoil species in lake settings, we can better understand their phenology and ecology to help guide management.
Researchers will be sampling ten different lakes with different combinations of northern, Eurasian, and hybrid watermilfoil throughout the summer. Visit our website for more information about Eurasian and hybrid watermilfoil.
MAISRC research shows Great Lakes still vulnerable to VHS
New research from MAISRC scientists Nick Phelps and Luis Escobar show that conditions in the Great Lakes are still right for an outbreak of VHS, a deadly fish virus. By looking at data from where outbreaks had previously occurred, scientists were able to predict the environmental conditions where it could occur in the future.
The virus tends to prefer cool waters and areas without heavy vegetation. Although no significant die-off events have occurred in Lake Superior, this research reminds managers and recreationalists in the area to stay vigilant.
“The Great Lakes obviously cover a massive area, which makes it extremely difficult to monitor,” said Dr. Nick Phelps. “By creating models like this, we can direct resource managers toward the areas that are most at risk for infection.”
VHS causes internal and external bleeding, which leads to organ failure and death in infected fish hosts. It can spread among locations via connected waters, the transfer of infected fish, and contaminated water and gear. Learn more about this disease and read the paper, Potential distribution of the viral hemorrhagic septicemia virus in the Great Lakes region here.
First AIS Detectors workshops a hit!
MAISRC’s new citizen science program, launched in partnership with University of Minnesota Extension, is off to a running start! The first in-person workshop was recently held in Andover, and participants learned everything from how to identify aquatic invasive plants, invertebrates, and fish to how to report a potential AIS, and more. Once trained, AIS Detectors will work as a liaison between the DNR and the general public, helping to rule out false reports of AIS. There are still several more workshops upcoming – but space is limited, so register soon!
Want to get a taste of being an AIS Detector? Try your hand at identifying aquatic invasive plants here!
Mark your calendars for the 2017 AIS Research and Management Showcase!
Please join us on Wednesday, September 13 for the 2017 AIS Research and Management Showcase. This event will help you gain valuable knowledge and insight to enhance your understanding of AIS issues and the research MAISRC is conducting. You will have opportunities for hands-on activities, lab tours, lunch with researchers, and more! Stay tuned for more details.
Presentations, papers, and awards
Dr. Przemek Bajer was invited to present at the Northwestern Fisheries Science Center, a division of NOAA. You can watch his talk, “The success of common carp across three ecoregions in Minnesota: drivers and consequences,” here.
Dr. Przemek Bajer and former graduate student Joey Lechelt recently published a new paper about the dispersal of common carp from marshes into lakes. The paper, Low downstream dispersal of young-of-year common carp from marshes into lakes in the Upper Mississippi River region and its implications for integrated pest management strategies, will be published soon.
Graduate student Josh Poole won the Best Student Presentation Award at the Minnesota Chapter of the American Fisheries Society’s annual meeting. His talk was on the control of common carp through biocontrol and species-specific toxin delivery, which you can learn more about here.
Dr. Peter Sorensen and former graduate student Aaron Claus recently published a new paper about how dissolved chemicals might assist food recognition in Bighead and Silver carp. You can read the paper, Chemical Cues which Include Amino Acids Mediate Species-Specific Feeding Behavior in Invasive Filter-Feeding Bigheaded Carps, here.
Graduate student Mike Verhoeven received a National Science Foundation Graduate Research Fellowship to support his research on aquatic invasive plant management. Mike is focusing on the effectiveness of controlling invasive species to boost native species, which you can learn more about here.
Undergraduate student Carli Wagner received first place in the student poster contest at the Midwest Aquatic Plant Management Society’s annual meeting. She presented on how starry stonewort remains viable following herbicide treatments, which you can learn more about here.
MAISRC in the News
- Lake Koronis is test lab in fight against invasive species (Minnesota Public Radio News)
- Aquatic Invasive Species spotlight (Pioneer Sportsman)
- Great Lakes vulnerable to outbreak of fish virus (Great Lakes Echo)
- Aquatic Invasive Species Detectors (Access Minnesota)
- Our mindset is the biggest obstacle to achieving success against aquatic invasive species (MinnPost)
- U of M's Donn Branstrator on spiny waterflea (WTIP Radio)
- First silver carp, the 'flying' invasive fish, is captured in St. Croix (Star Tribune)
- Registration for Citizens Aquatic Invasive Species program now open (Detroit Lakes Online)
- A tale of two fish: DNR reports first silver carp capture on St. Croix (Stillwater Gazette)
Here at MAISRC, we’re grateful for the support of private citizen and lake associations as we work to develop tools to detect, prevent, and control aquatic invasive species. If you or your lake association is considering a gift, consider what the Whitefish Area Property Owners Association had to say about why they give to MAISRC:
“The Whitefish Area Property Owners Association (WAPOA), a 1,200-member lake association in northern Crow Wing County, is actively engaged in watercraft inspections, education and information, and awareness of the threat of non-native aquatic invasive species (AIS) to the fourteen lakes comprising the Whitefish Chain of Lakes, as well as the more than 25 neighboring lakes. We consider the Minnesota Aquatic Invasive Species Research Center (MAISRC) as a “one of a kind” university-based research center actively engaged in long-term science-based solutions for the prevention and control of AIS. Our hope is that MAISRC will be our continual partner in Minnesota, and we are confident of that as we learn and understand the research underway, that enables all of us to aggressively manage and eliminate this present AIS threat. We support the Center and will continue to do so.”