News and Events

Thermal bars make appearance on Great Lakes

Fishers often refer to these areas as scum lines

Thermal bar formation in eastern Lake Superior nearshore zone along the south shore. | Michigan Sea Grant CoastWatch

Thermal bar formation in eastern Lake Superior nearshore zone along the south shore. | Michigan Sea Grant CoastWatch

Thermal bars are a characteristic of dimictic lakes of the temperate zone that mix from the surface to the bottom twice each year. During the winter months the Great Lakes are covered by ice and the amount varies depending on the severity of the winter. In the summer the Great Lakes become thermally stratified with temperature derived density differences that separates the lighter warmer water at the surface from the heavier colder bottom waters.

After a long winter the Great Lakes are isothermal or at the same water temperature from the top to the bottom. This is the time of the year when the water temperature throughout the Great Lakes is less than 39 0F (4 0C) and in the absence of any temperature or density differences readily mixes from the top to the bottom. As the nearshore water begins to warm in the spring it becomes lighter or less dense and separates from the denser or colder water farther from the shore. It is in this area of separation where the thermal bar develops. Water inside or nearshore the thermal bar is warmer than 39 0F (4 0C) and water outside or lake ward of the thermal bar is 39 0F (4 0C) or less.

In the spring, as Great Lakes surface water warms it becomes denser producing an unstable environment. This is the time that surface water sinks and develops a curtain of 39 0F (4 0C) water near the shore. Surface water flows toward this thermal bar region from the nearshore and lake ward sides of the lake and there is a pronounced downward flow of water at the point of convergence where the water temperature is 39 0F (4 0C). This is the region called the thermal bar or as fishers call it the “scum line” as insects and debris collect in this convergence zone that attracts fish. As spring warming occurs the thermal bar moves farther away from the shore. The water from the nearshore side of the thermal bar does not mix with water from the lake ward side.

Michigan Sea Grant and Michigan State University Extension provide daily surface water temperatures of the Great Lakes during cloud free periods that can be accessed through Michigan Sea Grant Coastwatch.

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The National Ocean Sciences Bowl Seeks Contributors to its Ocean Science Quiz


NOSB-Color-LogoAre you a marine or ocean science graduate student with a strong interest in education and outreach? Are you interested in earning some extra money this summer while helping to educate others about the ocean?

The National Ocean Sciences Bowl® (NOSB) is looking to hire question writers to contribute to our online game, the Ocean Sciences Quiz (OSQ). The NOSB ( is a national program, centered on an academic competition for high school students, that introduces students, teachers/coaches, schools and communities to the ocean as a resource to be protected and to ocean science as an interdisciplinary field of study and possible career path.

The NOSB’s Ocean Sciences Quiz (OSQ: was created to promote ocean literacy and engage students, teachers, teams and the general public worldwide. The online game simulates the NOSB buzzer competition, making the competition available to a broader audience regardless of age or location. Three game modes are available: a timed single-player version; a timed two-player version in which players must be using the same computer to compete; and a timed two-player version that allows players to compete over the internet (i.e., from different computers).

The OSQ is a fantastic tool for reaching a broader audience. To ensure it continues to engage all audiences and act as a resource for competing teams, the NOSB is seeking six graduate students to provide 50 questions each to help us enhance the game experience.  The questions can cover topics related to biology, chemistry, physics, geology, geography, technology, social science and marine policy. Each question writer can earn $200 upon submittal of the required 50 questions.

We need your help to continue our strong impact! To apply, please play the game for context and then send 3 multiple choice sample buzzer questions to Melissa Brodeur ( by COB Friday, June 26, 2015.

Melissa Brodeur
Program Manager, National Ocean Sciences Bowl |
Consortium for Ocean Leadership |
office: 202.448.1230 | fax: 202.332.8887

Follow NOSB on Facebook, Twitter, Tumblr and Instagram (#NOSBRocks)!

Celebrate Michigan Boating Week (June 6-14) and National Marina Day (June 13)

Event Date: 6/7/2015
End Date: 6/14/2015

News Release

Traverse city, beaches, beach erosion

June 8, 2015

Contact: Nicki PolanExecutive Director
Michigan Boating Industries Association
(734) 261-0123, ext. 4 |

NMD-Logo[Ann Arbor, Mich.] – It’s time to celebrate Michigan’s vast water resources and immensely popular boating opportunities. National Marina Day is Saturday, June 13, and provides potential new boaters and waterfront-lovers a chance to learn about recreational boating and visit a local marina. For local celebrations, consider visiting Michigan Clean Marinas. On Lake St. Clair, Bouvier Bridge Marina, MacRay Harbor and Sundog Marina have events planned. Additionally, several other marinas in Michigan are celebrating National Marina Day. Check out event details at

Michigan-Clean-Marina-logoCan’t make it to the water? Celebrate Michigan Boating Week by learning more about Clean Marinas. Certified Michigan Clean Marinas act to improve and maintain Michigan’s waterways by agreeing to reduce and eliminate releases and discharges of harmful pollutants, sediments, nutrients, general refuse, and anything else that can damage aquatic environments. Clean Marina operators and boaters have made the choice to do business in a way that is environmentally sound and business savvy. That’s worth celebrating.

Additional resources:

Free Fishing Weekend

Event Date: 6/13/2015
End Date: 6/14/2015

All fishing license fees will be waived for two days. Residents and out-of-state visitors may enjoy fishing on both inland and Great Lakes’ waters for all species of fish. All fishing regulations will still apply.

For many, the annual Free Fishing Weekend has become a tradition – a time to get together and have some fishing fun. While some may find time to reflect while fishing, there are no limits to variations on a great theme! Experienced anglers who offer a child or young adult the chance to take their first fishing trip can provide a rewarding experience for all. People who fish tend to understand the natural aquatic network of plants and animals that help to sustain fish as well as the regulations that govern fishing in Michigan.

Research shows that young people today do not have access to fishing opportunities that were enjoyed by generations before them. Some of the reasons: living in urban or suburban areas where fishing access is not readily available, competition for time by an ever-increasing schedule of special activities, and too little time for unstructured leisure.

Michigan offers some of the finest freshwater fishing in the world, with more than 3,000 miles of Great Lakes shoreline, more than 11,000 inland lakes and tens of thousands of miles of rivers and streams.

So grab a rod and your family and friends, and let’s go fishing!,4570,7-153-10364_52261_50497-194238–,00.html

This entry was posted in Events.

Hydrilla verticillata: Status of “the perfect aquatic weed”

Hydrilla tangled in a boat motor (Photo: Louisiana Sea Grant).

Hydrilla tangled in a boat motor (Photo: Louisiana Sea Grant).

By Mark Breederland, Michigan Sea Grant, Northwest Extension Educator

In August, 2006, the invasive plant Hydrilla verticillata was confirmed in a lake less than an hour’s drive from Michigan southern border, nearby, but outside of the Great Lakes drainage basin. Michigan Sea Grant and MSU Extension educators had begun in 2004 leading a statewide effort, in conjunction with the Michigan Department of Environmental Quality, to encourage waterfront property owners, boaters, anglers and swimmers to search the state’s inland lakes to make sure the weed had not infested bodies of water in Michigan. Sea Grant also asked recreational users to take precautions against potentially transporting hydrilla and other aquatic invasive species on their boat trailers and other gear. The good news is that no hydrilla was ever confirmed in Michigan and, after costly, drastic multi-year measures in treating Lake Manitou (near Rochester, Indiana, just 55 miles south of the Michigan border near U.S. 131), Indiana officials announced in 2009 that the problem was under control; they however, kept strictly enforced boating rules in place before and after boating on this lake.

Now, almost a decade later, the battle against this damaging weed continues inside the Great Lakes basin in the Tonawanda, New York area, near Buffalo. The weed was discovered by the U.S. Fish and Wildlife Service growing in the Erie Canal in 2012. The “Tonawanda Creek section” is a 15 mile stretch of the canal which empties into the Niagara River, one of the connecting channels of the Great Lakes system, and the hydrilla beds are listed as patchy and limited to the shallow shoreline areas outside the main navigational channel. On May 27, 2015, the US Army Corps of Engineers announced a public meeting to describe the hydrilla plant, present results of the 2014 treatment, provide a schedule and identify treatment areas for the 2015 field season.

Why is hydrilla the perfect aquatic weed? It is called perfect because it has many adaptive qualities and many methods of reproducing itself. The adaptive qualities allow it to outcompete and greatly diminish populations of native species. It can grow in low-light areas. It absorbs carbon from the water more efficiently than other plants. It is very tolerant to both standing and flowing water and can also grow up to an inch per day. Finally, its reproductive abilities make it particularly threatening. The tubers that grow from the roots can persist, in a viable state, in the lake bottom for several years. It can also reproduce through flowers, fragments and turions (cone-shaped growths) on its stalks.

The efforts in New York are hugely important, as this is a connected system into the Great Lakes and then potentially into Michigan. The Corps of Engineers has been working with the New York State Canal Corporation, New York State Department of Environmental Conservation, U.S. Fish and Wildlife Service, Ecology and Environment, Inc., and others to address and manage the excessive growth of this invasive plant.

While the “Michigan Hydrilla Hunt” campaign officially ceased several years ago, these materials may well be updated and readied for future education and outreach in order to prevent this most serious economic and environmental weed from gaining a foothold within Michigan.

Background information and a specimen identification card are available through the Michigan Sea Grant website.

It is illegal to possess hydrilla in Michigan (except to send it for identification) or to take the plant across state lines. Michigan residents and visitors can help prevent the spread of hydrilla by properly cleaning watercraft or other water recreation gear.

More information on invasive species prevention practices is available at


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Lunch & Learn: Storm Water Standards

Event Date: 6/5/2015

Macomb County Public Works Office
21777 Dunham Road
Clinton Township, MI 48036

The Macomb County Public Works Office will be updating our storm water standards this summer to remain compliant with state regulations. We have partnered with Michigan Sea Grant and Wayne State University to research and assist with technical guidance regarding drain design in order to improve the
usability and effectiveness of our standards.

Join us for a presentation and discussion about these important proposed changes to our standards.


  1. Introductions
  2. Current Standards and Feedback Received
  3. Sea Grant Project Overview
  4. Preliminary Findings
  5. Discussion on Proposed Improvements

Lunch will be provided.

Please RSVP to Jamie at by Wednesday, June 3, 2015.

One Continuing Education Credit will be provided for Professional Engineers.

4-H Great Lakes & Natural Resources Camp

Event Date: 8/2/2015
End Date: 8/8/2015

Young teens have fun and amazing outdoor hands-on learning experiences as they go charter fishing, snorkeling, sailing, hike through forests, wade through wetlands, explore dunes and more! This really fun MSU pre-college program could be the highlight of your summer – it could even change your life!

Learning sessions and recreation are designed to:

• Increase teens’ appreciation and enjoyment of the outdoors, natural resources, and science.

• Increase teens’ knowledge about the Great Lakes, natural resources ecology and management issues.

• Develop strong attitudinal attachment to Michigan’s unique natural resources and bioregional features.

• Foster scientifically rooted environmental stewardship.

• Develop and expand career and personal interests.

• Develop leadership skills and self-confidence.

• Increase social and academic skills needed for a successful transition to college and life as an adult.

Download the 2015 Great Lakes & Natural Resources Camp flyer and learn more by reviewing the one-page 2014 Impact Summary and 2014 Full Evaluation Report.

This entry was posted in Events.

Summer Discover Cruises 2015

Event Date: 5/9/2015
End Date: 9/19/2015


The 2015 Summer Discovery Cruises season begins Saturday, June 13! Registration is now open for both individuals and groups. For more cruise details and to register, go to

Favorite cruises from previous seasons will be offered, and some that are being added after a few years off the schedule. Learners will be able to explore the Great Lakes fishery (including the lake sturgeon – the largest fish in the Great Lakes), through the use of Remotely Operated Vehicles (ROVs), coastal wetlands, Great Lakes lighthouses, shipwrecks, the Great Lakes’ influence on weather (yes, you can ask National Weather Service scientists about the polar vortex!), how teachers can use Great Lakes science in the classroom, aquatic invasive species, and more.

Evaluations of the Summer Discovery Cruises program have documented positive program outcomes that are both widespread and significant. Data show that 95% of participants felt a greater responsibility for the Great Lakes following their Summer Discovery Cruises experience, 88% sought more information on Great Lakes topics of interest, and 23% engaged in new Great Lakes stewardship activities.

This entry was posted in Events.

Be Current Smart: New Water Safety Campaign


Photo Kurt Byers-Grand Haven Beach Safety waves

Photo: Kurt Byers

With summer just around the corner, millions of swimmers will soon flock to Great Lakes beaches. Rolling waves and light breezes are irresistible on a hot summer day, but waves and currents can be deadly. Sea Grant programs and partners in the Great Lakes region are announcing a new water safety campaign, Be Current Smart. The campaign includes tips for parents to keep a close eye on children while they’re near the water’s edge or in the water, and messages like “when the waves are high, stay dry,” and on the beach.

“Beach-goers can take simple steps to ensure a fun, safe day in the water,” said Todd Breiby, Wisconsin Coastal Management Program. “Parents have an important role in keeping a close watch on young children and making sure they are wearing life jackets.”

A key part of the campaign is the announcement of new water safety and emergency rescue equipment being deployed at hundreds of beaches in the Great Lakes region. Working groups in six states have collaborated with local and state officials on specifying and distributing equipment, including ring buoys and U.S. Coast Guard-approved life jackets for youth.

“First responders in the area are so pleased to get new equipment,” said Mike Molnar, Indiana Coastal Management Program. “With tight budgets, this equipment is coming at the perfect time and will be put to good use.”

Since 2002, dangerous currents, high waves and piers are related to the fatalities of more than 144 swimmers in the region. The Be Current Smart campaign includes a central website with links to animations; a video news release with interviews of U.S. Coast Guard, county sheriffs, and park officials; social media components; and news media resources.

“Throughout the Great Lakes, piers are the most dangerous place for swimmers,” said Matt Warner, Michigan Coastal Management Program. “Swimmers are encouraged to steer clear of piers because of dangerous structural currents.”

The Michigan Coastal Management Program supported the development of a suite of new resources, including beach sign templates, publications, lessons, diagrams and more. All materials are tailored for the Great Lakes region, are free and available for news media, beach communities, park staff, educators and others. See the Current Smart website for information about the campaign, and contacts in Illinois, Indiana, Michigan, Minnesota, Ohio and Wisconsin.


The NOAA Storms Program is supporting the Current Smart campaign, as part of the Implementing Dangerous Currents Best Practices project. Led by the Great Lakes Sea Grant Network, partners in this effort include state Coastal Management Programs, the NOAA National Weather Service, first responders, park officials and others. • Join the Discussion on Twitter: #currentsmart