November 2015 AIS Spotlight
Letter from the Director
When we started our search for solutions to AIS problems, we knew that it wouldn't be easy. We knew we would have to look far and wide for creative answers and that we would have to attract new minds to the effort. It's not just fisheries biologists or plant ecologists on our team; we also turned to experts in areas such as molecular biology, genetics, epidemiology, biochemistry, and more to address AIS problems.
That's why MAISRC is enlisting the help of the best and brightest postdocs from around the world to help us find solutions to these AIS problems.
MAISRC currently has nine postdocs – researchers who have completed their PhD but are not yet faculty members – on our team. I like to think of these postdocs as the engine that is powering our research center. They coordinate research projects, manage undergraduate assistants, and frequently present their findings through published papers and research symposia.
Several MAISRC postdocs have joined our team from other countries. Not only are they now providing their subject matter expertise to our AIS efforts, but Minnesota benefits from the lessons they have learned in other areas of the world where similar dynamics may be at play.
For example, our postdoctoral researcher working on zebra mussels, Sophie, hails from France where she studied the pathways of spread of the invasive pinewood nematode using genetic analysis. Meanwhile, Luis, who is developing a model to predict risk factors and likelihood of AIS invasions, previously used modeling to assess risks of avian flu in Guatemala and bat-borne diseases such as rabies in Chile.
Additionally, building on the knowledge she gained studying hormones and pheromones to understand the reproductive biology of elephants in India, Ratna is now using pheromones to detect and control common and Asian carps in Minnesota.
Of course, MAISRC also seeks and develops talent from closer to home. Four of our postdocs – Jessica, Dan, Sunil, and Adam Kokotovitch – earned their PhDs from the University of Minnesota. And now, all four are contributing to MAISRC's efforts to analyze risk, improve detection methods, and more effectively control invasive species. Adam Kautza received his PhD from Ohio State University and brings experience gained in Wisconsin and Idaho in fisheries ecology and food webs to his search for an effective biocontrol for Eurasian watermilfoil related to sunfish and weevils. Prince received his PhD from Marquette University in Wisconsin and brings expertise in using metagenomics to characterize microbial communities associated with key AIS such as Eurasian watermilfoil and zebra mussels in the search for controls.
Aquatic invasive species present a vexing challenge, and one that will not be solved overnight or in one fell swoop. Protecting our lakes and rivers from AIS will require a sustained, multi-pronged, creative, and powerful response from researchers, lawmakers, and citizens alike. Here at MAISRC, we're doing all that we can – including soliciting expertise from all over the world – to develop research-based solutions to reduce the impacts of AIS in Minnesota.
Dr. Susan Galatowitsch
Director, Minnesota Aquatic Invasive Species Research Center
New model suggests high percentage of Minnesota lakes susceptible to VHS
You probably already know about the risks that Viral Hemorrhagic Septicemia virus poses to Minnesota's waters. The pathogen – which has been found in all five Great Lakes and inland lakes in Michigan, New York, and Wisconsin – is unsightly and deadly to 34 species of fish. Moreover, it can survive in water independent of a host, rendering it incredibly difficult to monitor.
In order to most effectively and efficiently inform prevention efforts, researchers needed to know which lakes in Minnesota are at the highest risk for becoming infected. MAISRC researcher Dr. Luis Escobar, a postdoctoral associate working with Dr. Nick Phelps, was up to the task.
In partnership with the USGS, Escobar used remote sensing data generated by NASA satellites to determine the temperature, depth, and precipitation levels of all Minnesota lakes. By combining this data with what MAISRC researchers already know about VHS – including where it currently is found and what conditions it thrives in – Escobar was able to create a model that identifies which lakes are considered high-risk for infection.
"Unfortunately, this model shows that a high percentage of Minnesota lakes are susceptible to VHS," said Dr. Escobar. "But, we're still in a better position than the eastern Great Lakes area. And, having this knowledge will help us know where to dedicate the most attention in our attempts to prevent the spread of this disease."
Going forward, researchers will use this initial model as a base and add more variables to increase the sensitivity and accuracy. Adding which fish species are present, the density of those species, and the human and natural connectivity to other bodies of water will create an even better model. Escobar and Phelps are working with other MAISRC researchers to apply similar methods to additional invasive species, such as starry stonewort, to determine risk and susceptibility.
"This is a huge step in our understanding of VHS and will no doubt help in our fight against this disease," said Dr. Phelps. "With this information, agencies can focus prevention efforts based on evidence, not based on a hunch."
If you see a fish kill or catch a fish that you suspect may be infected with VHS or something else, report it at z.umn.edu/fishkill. Stay tuned to our website for a soon-to-be-published paper on this topic.
Promising new developments with Judas fish technology
In efforts to find control options for carp, MAISRC researchers have been exploring how to use the Judas fish technique to locate elusive Asian carps. This technique, in which individual fish are equipped with tracking devices and followed as they shoal with other members of their own species, could ultimately help inform lock and dam operations in the Mississippi River.
MAISRC researchers Dr. Peter Sorensen and Dr. Ratna Ghosal developed this method based on work being done in Australia, and it has since successfully been used in Minnesota to remove and control common carp populations. They have recently described several promising new developments that will improve this detection and management strategy.
- Juvenile silver and bigheaded carps have been found to shoal, indicating that the Judas fish technique has promise to lead biologists to schools of other carps. Ghosal is also looking at ways to use pheromones to enhance the likelihood of shoaling and working to pair this with eDNA techniques to better measure their presence. Silver and bigheaded carps have also been found to shoal together. This behavior may explain why these fish have been found to hybridize.
- In order to use the Judas fish technique with Asian carps, it's crucial that the fish is reproductively sterilized before it is released and tracked. In the course of developing these sterilization procedures for carps in the lab with veterinarians Amy Kizer and Betty Kramek – who are generously donating their services – Ghosal and Sorensen found that common carp can completely regenerate their reproductive organs and grow around vasectomy clips. This surprising development followed a year of monitoring and suggests that different techniques will need to be developed for Asian carps.
- As one of these possible new techniques, Ghosal and Sorensen are now also working with engineers at Advanced Telemetry Systems to help develop an automated system to inject a Judas fish with a lethal dose of poison using a timer. The implanted device would be triggered after the sterilized fish has led managers to groups of other invasive fish – but before it could regenerate its reproductive organs.
"This incremental progress is showing great promise for locating and blocking these elusive carp. They outsmart sampling gear, nets and traps, so we have to get creative to find solutions for control," said Ghosal.
In order to test the use of the concept using pheromone-scented Judas fish in the field, researchers recently released radio-tagged common carp implanted with pheromone capsules in Long Lake (a collaboration with the Rice Lake Watershed District and the National Science Foundation) and will be tracking its movement and shoaling behavior. Stay tuned for more updates as this work progresses.
In case you missed it: MAISRC in the news
"Researchers have been working on the pathogen for several years, but concerns over its spread have now made it a high priority, particularly given its impact on "economically and ecologically important" species, including yellow perch and walleye." Read more:
- U studies spreading fish parasite in Minnesota lakes
- Parasite attacking Minnesota fish
- Disease dissolves game fish
"These researchers are doing something that's never been done before: mapping the genetic fingerprint of the zebra mussel. This is the beginning of the research that one day could help wipe them out." Read more:
- U of M lab mapping DNA of zebra mussels to slow spread
- DNR begins zebra mussel pilot project treatment
- Researchers sequence mussel DNA
- Researchers to try to map genome of zebra mussel
"But researchers have learned a lot about common carp in the last decade, he said, and controlling them is possible.The latest research and management efforts are happening in a system of lakes in the north metro area that are all connected by Rice Creek." Read more:
- Scientists trying to make common carp a lot less so
- Startup takes aim at invasive carp threat in Minnesota lakes
- Researchers working to combat common carp in Minnesota
New aquatic invasive species Extension program coming soon!
MAISRC is excited to announce that in partnership with University of Minnesota Extension, two new programs – AIS Detectors and AIS Trackers – will be launched soon. Anyone who is interested in helping detect and track nuisance AIS species like zebra mussels, Eurasian watermilfoil, and others should sign up here to receive more details as the program develops. Do your part to help prevent the spread of aquatic invasive species!
MAISRC is hiring
MAISRC is looking for a full-time Extension Educator who will be responsible for developing, implementing, and evaluating educational programs that build local capacity for aquatic invasive species detection and response. These educational programs will provide training and tools to local governments, lake associations, AIS professionals, and citizens groups to prevent, detect, monitor, track, and control the establishment and spread of state-listed aquatic invasive species. Learn more and find instructions for applying here.
MAISRC welcomes four new team members
MAISRC is excited to welcome four new researchers to our team: Adam Doll, Luis Escobar, Prince Mathai, and Sunil Kumar Mor. Read more about them and their research here.
Presentations from the 2015 Minnesota Aquatic Invasive Species Research and Management Showcase are now available online
If you missed September's Showcase and want to check out presentations and handouts, look no further! Topics included fish diseases, zebra mussels, harmful microbes, aquatic plants, and more. Also, visit MAISRC on Facebook to view photos from the event. Thanks to all who attended!
MAISRC student wins Conservation Biology Graduate student of the Year award
Congratulations to MAISRC student Joey Lechelt for recently winning the Graduate Student of the Year award from the Conservation Biology department at the University of Minnesota! Joey is studying factors that influence young of year common carp survival, specifically bluegill predation on carp eggs, larval carp diet, and carp out-migration from winterkill-prone marshes.
Support MAISRC with a gift today
Researchers at MAISRC are working diligently to address aquatic invasive species issues that are threatening Minnesota's lakes and rivers. Oftentimes, this research requires an outdoor field component. Whether it's tracking the movement of common carp, sampling for zebra mussel veligers, or removing Eurasian watermilfoil, our researchers need motors, boats, trailers, and other capital equipment to keep advancing their research. Help us do this critical work with a gift today. Private contributions to MAISRC make a real difference and provide us with the flexibility to meet critical needs as they arise. Thank you for your support!