Management activities at St. Joseph Bay Aquatic Preserve have been discontinued as of July 1, 2011. This page describes one of the former ecosystem science programs which will be restarted should revenue streams improve.

Seagrass communities are considered to be the most productive ecosystems in the world. They provide a protected nursery and foraging area for many marine species, and their root system aids in water clarity. They also serve as indicator species because they are very sensitive to changes in water quality. In St. Joseph Bay, one-sixth of the bay bottom is seagrass meadows. Monitoring these habitats is the best way to determine the overall health of the aquatic environment.

As human populations concentrate along coastlines, impacts to seagrass habitats increase. Nutrient loading from runoff, increased turbidity and phytoplankton blooms, and increased boat traffic and vessel impacts such as propeller scarring can harm seagrass health.

The preserve monitored 16 seagrass sites within the bay twice a year, at the beginning and end of the growing season. The goals of the project were to:

• determine seagrass distribution and abundance,
• determine trends in seagrass conditions,
• determine the health of beds through water quality monitoring data, and
• compare current seagrass maps to historical maps.

The seagrass data was analyzed to determine trends and supplied valuable information about the dominant species in the bay as well as the conditions at which these species thrive. Further data analysis, together with hyperspectral mapping, advanced GPS technology, and biological and water quality monitoring efforts was planned in order to give an excellent overview of the current health of the seagrass community in St. Joseph Bay.

• Seagrass Habitat of St. Joseph Bay (PDF - 782 KB)
• Seagrass Monitoring Sites in St. Joseph Bay (PDF - 810 KB)
• Seagrass Scarring in St. Joseph Bay (PDF - 333 KB)

More information on the Seagrass Monitoring Program at St. Joseph Bay Aquatic Preserve is available in the St. Joseph Bay Aquatic Preserve Management Plan.