“ The Heart of the Bay ”

1. “The Heart of the Bay” • Research Directions • CAPMON System • Crab heart rates can be measured using the Computer-Aided Physiological Monitoring (CAPMON) system. • This requires placing a sensor on the crab’s shell directly over the heart. An infrared beam from the CAPMON unit is emitted through the shell and on to the heart muscle tissue. As the heart changes shape, the amount of light reflected back to the sensor also changes. A detector measures these changes, and its presented on a computer monitor. • Maryland Sea Grant • Summer Research Fellowship • Objectives for 2003 • Determine basal heart rate of the blue crab • Measure crabs’ heart rate in changing salinity • Investigate impact of harmful algae on heart rate • Preliminary data • Investigations into the effect of changes in salinity on the heart rate of blue crab are shown below. • Education Applications • Education Possibilities • Increase understanding of how marine organisms may serve as early indicators of pollution. • Provide an opportunity for students to use authentic research tasks. • Students can make connections between environmental health and water quality and the health of living organisms.. • Educational Activities • Collecting organisms in the field • Hands-on monitoring of organisms’ heartbeats in the lab • Researching the water quality of local waters • Related Topics • Marine Biology • Coastal Ecology • Environmental Science • Marine Organisms as Indicators of Ocean Health • Local and Global Environmental Concerns • Invasive Species • Harmful Algal Blooms • Public Health and Water Quality Monitoring • Aquaculture • Physiology of Crabs and Muscles • Monitoring Stress • Measuring the Heartbeat of the Bay • Monitoring a crab's heartbeat provides an indication of its health, in the same way that a doctor checks a human's pulse. • This monitoring uses a non-invasive scientific technology to assess how well crabs or mussels adapt to stress in the aquatic environment. • A Crab with Heart • Blue Crab (Callinectes sapidus) has an open circulatory system, the heart circulates hemolymph throughout the body. • A crab’s heart is located dorsally in the center of the carapace and is suspended under the surface of the carapace by strands of connective tissue. • Bioindicators • Marine organisms can be used as bioindicators of aquatic contamination, and may serve as an early warning of pollution in our waters. • The earlier we become aware of aquatic pollution, the better chance we have to control or remediate it. • Stress • There are natural stressors, such as climate change or food availability, and human-induced stressors, such as pollution or dredging activity. • A crab’s physiological responses can be used to indicate exposure to stress such as pollution or harmful algae. Dr. Allen R. Place, Center of Marine Biotechnology Mr. Oded Zmora, Center of Marine Biotechnology Ms. Reuwai M. Hanewald, The Park School Mr. J. AdamFrederick, Maryland Sea Grant The College of Exploration, Virginia