During a cruise, many activities are happening at once, and students will be absorbing a ton of information about lakes and their environment. For some students, being on a boat is itself a novel experience, let alone engaging in new and challenging science activities. Participants will maximize their experience if they have been briefed on the activities prior to the trip. Safety handouts are provided during the cruise registration process. This information is essential for the group to prepare to have a safe and successful cruise. Lessons before and after a cruise on related topics will increase students’ familiarity with the topics and terminology covered on a cruise, helping them to deepen their learning and engagement with the topics. 

Whether groups are sailing on the D.J. Angus or the W.G. Jackson, they will have the opportunity to be aquatic scientists. Both vessels offer the same overall trip structure and curriculum, with place-based variations appropriate to their settings. In general, cruises illustrate the biological, physical, and chemical dynamics of water, and the interrelationships of rivers, inland lakes, and the Great Lakes. The onboard curriculum is structured around conducting water quality tests and other observations to compare and contrast Lake Michigan with smaller inland lakes and rivers. 

The specific topics and depth of coverage vary with age level, and AWRI Science Instructors are prepared to adapt to the needs of the visiting group. The program serves school groups as well as other organizations. It can be customized for all ages from fourth grade through adults. 

Upon arrival, AWRI Science Instructors will welcome the group and orient them to the vessel and its safety features and procedures. They will also provide an introduction to where the students are, the water bodies they are visiting, and what they will have an opportunity to do onboard that day.

On a typical 2.5 hour cruise, the vessel will stop at two locations (or stations) to take water samples, conduct analysis, and make observations. Stations are sampled and analyzed on a cruise for the purpose of comparing different bodies of water. Most cruises will do one station on Lake Michigan and one on a connected inland waterway (such as Muskegon Lake or Spring Lake). If Lake Michigan is too rough, the cruise will visit other areas of the inland lakes or rivers for the second station. Shorter cruises can be provided upon request, but two stations may not be possible during shortened cruises. 

Every student will have an opportunity to work directly with multiple pieces of real science equipment to make measurements and observations at each station outdoors and inside the ship’s lab. AWRI Science Instructors provide students as many different experiences onboard as possible by giving new assignments at each station. For each test or observation, the instructors will orient participants to the water quality parameter being measured, the significance of this measurement to freshwater ecosystems, and the equipment and procedures to conduct the analysis. They will support the students in developing their comfort with the process of science and having success with their assigned tasks.

While the vessel is sailing between stations, science instructors share information about a range of topics, including:

• Lake food webs
• Human impacts to water quality
• Restoration and environmental clean up efforts on local and regional lakes
• Invasive species
• Research conducted by AWRI scientists
• Landmarks and place features that the vessel is sailing by
• Shoreline structures and activities, and their potential influence on water quality
• Lake stratification and temperature profiles
• Climate Change and aquatic ecosystems
• Watersheds
• The significance of the Great Lakes and freshwater resources

Under the umbrella of freshwater science, particular topics can be emphasized within our curriculum upon request.

At the end of a cruise, the data collected over the course of the voyage will be analyzed and interpreted to make claims about what the data mean, and what conclusions can be drawn about the water that was sampled during the cruise. AWRI Science Instructors will facilitate review of data from each station and comparison of values from the different stations. Students will discuss actual versus expected values and trends, and practical applications of physical, chemical, and biological concepts. Instructors will answer questions from students as well as summarize key takeaways from the cruise.

Students and teachers can take their data and/or plankton and water samples (upon request) back to the classroom for further study and discussion. The data from a group’s cruise can be analyzed further on its own, or in the context of other water quality data. The archive of data from AWRI cruises since 1986 is available online at http://9dap.eduftp.net/wri/education/vessel-program-data-archive-59.htm. As well, the Muskegon Lake Observatory provides real-time data from April to October for comparison: http://9dap.eduftp.net/wri/buoy/ 

The W.G. Jackson leaves the dock at AWRI on Muskegon Lake and makes its way across the lake to Lake Michigan. Muskegon Lake is 4,149 acres or about 6.5 square miles in size. Many of the industrial areas along the shoreline of Muskegon Lake are being restored to pre-industrial conditions or re-developed. The area once had active logging and numerous industrial operations. Homes and marinas also surround the lake. Significant heavy industrial activity along with wastewater discharge, combined sewer overflows, and urban runoff in the past have led to contamination. In 1987, Muskegon Lake was designated an “Area of Concern” under the Great Lakes Water Quality Agreement. Through concerted restoration efforts since, the Lake is very close to being delisted and has much higher water quality today. The Muskegon River watershed drains into Muskegon Lake and influences the water quality. Besides Muskegon and Big Rapids, the watershed has no large cities and is relatively undeveloped.

The D.J. Angus makes a trip to Lake Michigan via the Grand River. Along the route to Lake Michigan, there is a former sand mining operation, a large commercial unloading dock, marinas, and a former power plant. The headwaters of the Grand River are near the city of Jackson and the river also flows through the cities of Lansing and Grand Rapids. Besides urban areas, land use in this watershed is largely devoted to agriculture with relatively few natural areas. The other sampling point for the D.J. Angus is usually in Spring Lake, which is connected to the Grand River. Spring Lake is surrounded mainly by homes and has experienced elevated nutrient levels. 

Lake Michigan has a surface area of about 22,300 square miles making it the third largest Great Lake. The flushing time of the Lake (or the average amount of time that water spends in the lake) is 62 years. The average depth of Lake Michigan is 279 feet with a maximum depth of 923 feet, making it the second deepest Great Lake. In contrast, Spring Lake's surface area is about 2 square miles with inputs of water mainly through springs, streams, and precipitation. Spring Lake is connected to the Grand River. Muskegon Lake is about 6.5 square miles in size, and it receives flow from the Muskegon River as well as tributaries such as Ryerson and Ruddiman Creeks.

One way of comparing lakes and evaluating water quality is by considering the trophic status or biological productivity. Eutrophication, or aging of lakes, progresses through various trophic states (oligotrophic → mesotrophic → eutrophic). Nutrient levels, organic matter content, dissolved oxygen levels, and water transparency give clues to the trophic state or biological productivity of a water body. A trophic scale has been specially designed for use on the AWRI vessels. By evaluating data from various parameters, sampling locations are rated as O (oligotrophic), M (mesotrophic), or E (eutrophic). 

Oligotrophic lakes are characterized by low nutrient levels, low biomass, high oxygen concentrations, and high transparency. Oligotrophic lakes are usually deep. Eutrophic lakes are highly productive with high nutrient levels, high biomass, low oxygen concentration in the bottom waters, and low transparency. The large volume of organic matter accumulated in bottom sediments depletes oxygen as it decomposes. Mesotrophic lakes are between the other two trophic states in their characteristics. The open waters of Lake Michigan are oligotrophic and some nearshore areas are mesotrophic. 

The vessels use Van Dorn water sampling bottles to collect samples at various depths. These special bottles consist of an open-ended clear plastic cylinder that can be attached to a steel cord and lowered to any desired depth. A deckhand operates this equipment, but when conditions permit, will select 1-2 students to assist with this task. The bottles also contain thermometers to record the temperature of the water at the location of each Van Dorn bottle. Water samples from each bottle are taken into the ship’s lab for analysis. On a typical cruise, two Van Dorn bottles are used: one 1 meter below the water surface and one 1 meter above the lake bottom. This allows us to compare and contrast the characteristics of the top and bottom of the water column. On more advanced or longer cruises, a third bottle may be added to sample at half the station depth.