January 10th, 2017 by IISG
Researchers at Purdue University are suggesting that fishing by Lake Michigan charter boat anglers has changed in recent years—and the scientists didn’t even have to visit the lake to notice these differences.
In fact, Nicholas Simpson who is the primary author on the study has never even fished Lake Michigan.
Working with Tomas Höök, fisheries ecologist and IISG associate director for research, Simpson, then an undergraduate, compiled 21 years of charter fishing data obtained from the Illinois, Michigan, and Wisconsin Departments of Natural Resources (DNR).
The data, derived from more than 500,000 trips, were readily available from the records charter anglers are required to report to their state DNR after each trip: number of fish harvested—not just caught, location fished, and hours spent fishing.
Simpson, Höök, and their co-authors evaluated patterns for five salmonid species—brown trout, Chinook salmon, coho salmon, lake trout, rainbow trout—harvested from May to September during 1992–2012.
“Because we’re looking at charter fisherman data, there are some biases,” Höök acknowledged. “They’re not randomly going out to catch fish. They go where they believe they’re more likely to catch fish.”
But there is an advantage to examining these data. Researchers often attempt to catch fish in a systematic, unbiased way, and may be limited by factors, such as funding timelines or resources. As a result, “the number of times the lake is fished or the overall number of fish caught wouldn’t be that much,” Höök pointed out. “Here we’re taking advantage of a huge number of people fishing over a long time period.”
The data set covers a time when the lake itself has changed dramatically. Lake temperature and other physical and biological factors are different today than they were in 1992. Over the course of the data set, the distribution and number of prey fish, such as alewives, available for salmon varied greatly.
In addition, while it may be hard to remember a time when zebra and quagga mussels—invasive filter feeders—didn’t line almost every inch of Lake Michigan, zebra mussels were just becoming an issue in the first year of data. Numerous studies have suggested that the mussels have changed the structure of the Lake Michigan food web over time.
The researchers assumed that salmonid species would not be immune to these changes, and some patterns emerged from the charter anglers’ records.
Over time, the amount of time charter anglers spent fishing increased. The anglers also shifted their efforts closer to shore and toward the western and northern parts of Lake Michigan. However, patterns in the harvest of individual salmonid species paint a complicated picture.
Harvest of lake trout and rainbow trout by charter anglers shifted closer to the shore. The same was not true for Chinook and coho, where harvest was consistently farther out in the lake. Brown trout were harvested progressively further west and south, while lake trout were harvested progressively further east. Multiple species were harvested in new locations and at new depths.
In general, the researchers suggest that many of the changes are related to salmonid feeding.
“Previous research has shown the brown trout and rainbow trout and to an extent lake trout are a little more flexible in their diets,” Simpson said. “They were more apt to shift closer to shore and to shallower depths for food. Chinook salmon and coho salmon may not have displayed those trends because they’re more reliant on alewife as prey, which tend to live farther out in the lake.”
“There’s no previous research in the literature that would suggest that coho or Chinook salmon would vary their diet as much as the other three species,” Simpson added.
The researchers stopped short of definitively declaring that fish are changing where they dwell in response to changes in distributions of Lake Michigan nutrients and prey, but they’re confident the results from this paper will be useful.
“The depth and breadth of this data set is what makes it powerful,” said Höök. “While we have to be aware of the biases, fisheries researchers do use catch and harvest data to infer species distributions.”
And while fisheries managers will ultimately need to consider this analysis alongside their own monitoring efforts, Simpson said, “I think it’s useful for fisheries managers especially on Lake Michigan to be able to see that there are shifts occurring.
The study on their findings was recently published in the Journal of Great Lakes Research.
Illinois-Indiana Sea Grant is a part of University of Illinois Extension and Purdue Extension.
October 27th, 2015 by iisg_superadmin
“Be A Hero” is now the primary invasive species awareness campaign in Illinois. Boaters, anglers, and divers have heard this message, but now the comprehensive campaign provides easy tips to help water gardeners, teachers and aquarium hobbyists curb the spread of aquatic invaders. Plus, Be A Hero also provides guidance to hunters, campers and hikers to prevent the spread of species that threaten habitats on land.
“The problem of invasive species in our Illinois waters and lands has never been worse than it is today,” said Paul Deizman, who leads forest management at the Illinois Department of Natural Resources (IDNR). “Unfortunately, without action, the problem of invasive species—which are displacing natural flora and fauna as well as interfering in land and water management, critical ecological processes and biodiversity—could become irreversible.
For example, many commercially-sold plants and animals pose a risk to Illinois habitats. In fact, plants like Brazilian elodea, often sold as anacharis, have already reached several Illinois lakes and ponds, where they often form mats that block sunlight needed by other species and hinder recreation. And more invaders lurk on the horizon.
To prevent their spread, Be A Hero—Release Zero™ introduces teachers, water gardeners, aquarium hobbyists, and others who buy and sell species to safe alternatives to releasing unwanted plants and animals.
In addition, Be A Hero—Transport Zero™ now also addresses the spread of terrestrial invaders with tips for hikers, campers, and hunters who may accidentally carry species to new habitats.
Be A Hero kicked off in 2013 with a media campaign encouraging recreational water users to take simple steps—remove, drain, and dry—after a day on the water. Be A Hero—Transport Zero™ messages have also been shared one-on-one at boat shows and fishing tournaments. An IISG survey of boat show attendees found that people who have heard these messages are more likely to take action to prevent the spread of invasive species.
“We have found that the Be A Hero message resonates with anglers and boaters as we talk with them at state fair and other venues,” said Kevin Irons, IDNR aquatic invasive species program manager, “Be A Hero is unique in efforts to raise awareness about this issue. It is a positive message.”
“This campaign is an important and significant outreach and marketing tool we absolutely need,” Deizman added. “It is great to have the three Be A Hero logos working together to make headway on the invasive species problem in Illinois.”
Be A Hero is a collaboration between IDNR and Illinois-Indiana Sea Grant (IISG). “Now that we have launched the campaigns, we are looking for partners to help us get the word out,” said Pat Charlebois, IISG aquatic invasive species outreach coordinator. “We have graphics that your organization can use online, at public events and on promotional materials.”
May 14th, 2015 by iisg_superadmin
INVASIVE SPECIES EDITION—Where we take a moment to explore the species that threaten the Great Lakes region.
They may not be what comes to mind when you think of invasive carp, but grass carp can have drastic and lasting impacts on aquatic ecosystems and water quality. Originally from eastern Asia, they have been introduced the world over as a biocontrol for aquatic weeds and can now be found in over 70 countries.
This wide range is made possible by their versatility—not unlike the hydrilla they are sometimes employed to eliminate. Grass carp can live in water temperatures from below freezing to over 100ºF, can survive in brackish waters, and are able to tolerate low-oxygen environments.
While they live mostly in slow moving and still waters, eggs are spawned in fast rivers, and must remain suspended for two to four days before they hatch. From there, grass carp grow quickly—as much as 10 inches in the first three months. An adult can grow to be upwards of 4 feet in length and more than 50 pounds on a diet of mostly aquatic weeds. But they have also been known to consume detritus, insects, and other invertebrates as well.
Grass carp were first brought to the U.S. in 1963 when they were imported from Malaysia and Thailand to aquaculture facilities in Alabama and Arkansas. Their first release into the wild is believed to have happened three years later when some escaped from the U.S. Fish and Wildlife Service Fish Farming Experimental Station in Stuttgart, Arkansas. Planned introductions began in 1969 in an effort to control nuisance plants. By the end of the 1970s, grass carp had been introduced in 40 states. Today it can be found in 45 states, with well-established populations throughout the Mississippi River Basin.
Grass carp are a highly regulated species, and for good reason. Because they are so adept at consuming plants, there is a risk that these veritable aquatic lawnmowers might leave a waterbody completely devoid of plant life and wipe out the food supply for other fish, insects, and waterfowl. A lack of plant life can also spur on algal blooms, which in turn lower oxygen levels. And without roots to keep sediment secure, the water is likely to become muddied, and spawning beds for other fish can be destroyed.
Because of these and other risks, grass carp used for weed control are sterilized by shocking the eggs with drastic changes in either temperature or pressure. But this process is not 100 percent effective, and fish sometimes escape into the wild. In some states, including Illinois, the use of grass carp is restricted to private ponds or pools. Those thinking about using the fish for personal use are encouraged to explore other weed-control options.
April 27th, 2015 by iisg_superadmin
The Wonder Lake Master Property Owners Association is reminding boaters, anglers, and water skiers to remove, drain, and dry after a day on the water to prevent the spread of invasive species. These Be a Hero—Transport Zero™ steps can now be found at 14 boat ramps around the Illinois private lake.
The signs were installed during the annual spring cleanup, one of many events hosted by the Wonder Lake Sportsman’s Club. And it’s just the latest effort designed to raise awareness of aquatic invasive species and how they spread.
The recent surge of outreach at Wonder Lake is largely driven by concern over invasive plants like Phragmites, a species that’s spreading quickly across the Great Lakes region. Plant life along the lakeshore is limited now, but an ongoing dredging project is expected to change that.
Randy Stowe, the lake manager, wants to make sure that the species that move in don’t pose a threat to habitats and recreation.
“We’ll be reaching out to those who own the land along the lake to educate them about invasive plants—how to recognize them, and what to do if you find one,” said Stowe. “We’re really trying to stay ahead of things.”
Learn more about how you can fight the spread of invasive species at TransportZero.org.
***Photo credit: Wonder Lake Sportsman’s Club
January 29th, 2015 by iisg_superadmin
Water gardeners—keep your eyes open this season for invasive plants that may be lurking at your neighborhood garden store. In recent years, Illinois and Indiana DNR have both added nearly 30 new species to their lists of banned aquatic plants, but some may still be available for sale.
If you spot one of these invaders, be sure to tell the store manager. Some species can be hard to identify and larger stores may not even know these plants are on their shipment list. That’s exactly what was happening at a Petco in Carbondale, IL, where Karla Gage found Brazilian elodea—aka Egeria densa—while browsing with her family.
“I notified the department manager that this was listed as an injurious species in Illinois, and I sent a follow up email to the store manager,” said Karla, coordinator of the River to River Cooperative Weed Management Area, which brings together federal, state, local, and private partners to tackle invasive plants in southern Illinois. “I received a call from the corporate contact, who stated that Petco stores in Illinois would no longer receive or be able to order Brazilian elodea. Previously, Carbondale stock had been on “auto-replenish,” so the stores never actually ordered Brazilian elodea. Current stock is being disposed of responsibly.”
“Thanks to Admin Code 805 and the quick response of Petco,” she added, “the risk of an introduction of Brazilian elodea into natural systems has been reduced.”
The Illinois and Indiana rules also make it illegal to gift, barter, exchange, loan, or transport the any listed species. Recent additions to the list—27 plant species in Illinois and 28 in Indiana—were chosen based on the results of a risk assessment tool developed in Indiana by the Aquatic Plant Working Group. The tool evaluates species based on factors like ability to thrive in the Great Lakes and difficulty to control. IISG’s aquatic invasive species (AIS) team organized and facilitated the group, which included representatives from the aquatic plant industry, aquarium and water garden hobbyists, state agencies, academia, and non-governmental organizations.
Visit our AIS page for more information about invasive plants and animals on the market and what water gardeners and aquarium hobbyists can do to prevent their spread.
***Photo courtesy of Graves Lovell, Alabama Department of Conservation and Natural Resources, Bugwood.org.
December 19th, 2014 by iisg_superadmin
2014 has been an exciting year for IISG. New partnerships were forged, major projects were launched, and existing programs continued to grow. As we head towards another new year, let’s take a look back at some of the highlights of the last 12 months.
–More than $300,000 was awarded to three research projects that will improve understanding of the Lake Michigan nearshore food web, uncover connections between sediment removal projects and a community’s ability to weather environmental hazards, and identify why people adopt stormwater management practices.
–The Great Lakes Social Science Network gave researchers, natural resource managers, weather forecasters, and educators the information they need to ensure safety and planning messages meet the needs of local communities.
–A mobile app offering a self-guided walking tour of Chicago’s historic and scenic downtown shoreline was released for Android and iOS.
–We said goodbye to several staff members and friends and welcomed 10 more to the team.
–The Illinois Clean Marina Program celebrated one year and six certifications.
–We got some help spreading the word about AIS prevention from celebrity newcomers Lady Quagga and Jumpin’ Jack.
–The Michigan City buoy returned to the nearshore waters of Lake Michigan with a new sensor chain that measures temperatures at different depths.
–Illinois Governor Pat Quinn announced a $1.1 million investment in Blue Island to expand and improve stormwater management efforts that began in partnership with IISG.
–Great Lakes Monitoring made it possible for researchers to analyze decades of high-quality monitoring data from across the region in minutes.
–Illinois EPA and the state Department of Agriculture released a plan to reduce the nutrient pollution behind the Gulf ‘Dead Zone.’
A big thanks to all of the partners and collaborates that made these and other 2014 successes possible!
December 10th, 2014 by iisg_superadmin
A closer look at web tools and sites that boost research and empower Great Lakes communities to secure a healthy environment and economy.
It’s getting a little chilly for a stroll in the Windy City, but don’t let that stop you from enjoying it’s beautiful downtown lakefront. With Chicago Water Walk, you can explore some of the city’s most celebrated sites—Navy Pier, the Chicago River, downtown marinas, Buckingham Fountain, and Museum Campus—from anywhere.
The mobile-friendly website takes viewers on a journey through time to discover how Lake Michigan and the Chicago River transformed a small trading post into one of the economic and cultural hubs of the world—and the vital role these natural resources play in the city’s present and future.
Each stop in the virtual tour combines history, current events, and water sciences with fun facts to show the importance of aquatic ecosystems in the city’s past, present, and future. Stunning photos, historical images, and links to videos and other resources bring these issues to life and reveal a lakefront that will surprise even lifelong Chicagoans.
Visit the website and you’ll learn why the decision to reverse the Chicago River is still making waves more than a century later, how a city that sits along Lake Michigan can be concerned about having enough water in the future, and how native trees and plants are helping the city prepare for changing weather patterns. You’ll also hear about efforts to restore much-needed habitats for millions of birds, fish, and other wildlife.
And for those willing to brave the cold, a mobile tour app is available for free on Apple devices. You can follow the suggested routes or visit the sites that most appeal to you using the app’s interactive map.
The Chicago Water Walk website and app were developed by Illinois-Indiana Sea Grant with funding from the Illinois Department of Natural Resources Coastal Management Program and technical support from the University of Illinois Administrative Information Technology Services.
November 5th, 2014 by iisg_superadmin
In Alaska’s Kachemak Bay Research Reserve, invasive species prevention is taking on a new look. To prevent the spread of the invasive invertebrates while a local harbor undergoes renovations, officials have adopted the Be a Hero – Transport Zero logo and slightly modified the message to encourage those involved in the reconstruction to follow a few easy before moving all docks and other infrastructure.
Closer to home, the outreach campaign developed by Illinois-Indiana Sea Grant and the Illinois Department of Natural Resources is also expanding to include hunting, hiking, and other terrestrial pathways. Posters asking customers to “join the fight” can be found in outdoor supply shops in several Illinois cities, including Springfield. The message also made an appearance at this year’s state fair in August.
When it launched last year, Be a Hero – Transport Zero became the primary invasive species prevention message in Illinois. It’s simple call for boaters, anglers, and other recreational water users to “remove, drain, dry” before leaving a waterbody has been featured in magazines, broadcast on radio and television, and wrapped into outreach programs like Clean Boats Crew.
To learn more about aquatic invasive species and what you can do to prevent their spread, visit our invasive species page.
August 27th, 2014 by iisg_superadmin
Summer is coming to an end, but there is still plenty of fun to be had this weekend. If you’re like us, you’re anxious to hit the road to your favorite beach, boat launch, or fishing spot. But before you do, we have a message that will help keep these places healthy for many Labor Days to come. And you may just see it on the car in front of you.
The Illinois Department of Natural Resources has emblazoned nine vehicles with a reminder to Be a Hero—Transport Zero. It’s all part of a statewide program that is raising awareness about how the public can help prevent the spread of invasive species on land and in waterways. These plants and animals can wreak havoc on food webs, water quality, and recreation. The three featured in IDNR’s tailgate designs—Asian carp, zebra mussel, and hydrilla—are some of the worst offenders, but there are many more, and they aren’t always easy to recognize.
So what can you do? Just follow three easy steps before you leave the water this weekend:
– Remove any plants, animals, and mud from boats, trailers, and equipment
– Drain everything—bait buckets, live wells, etc.
– Dry everything with a towel
From boaters and kayakers to waterfowl hunters, scuba divers, swimmers, and more, we can all help prevent invasive species from taking over our favorite waterways.
See you on the water!
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