Bivalves, which include mussels, oysters, scallops and clams, play an important role in ecosystem functioning. As filter feeders, bivalves continuously taste the water for food. When they taste something they don't like they can either reject the particles via pseudofeces or, in the case of more soluble pollution, close their shell for protection. By monitoring the opening and closing of bivalve shells in real time, we can detect pollution events as they occur. This enables the source of the pollution to be identified.
Man made pollutants can have a range of impacts on aquatic fauna and under certain conditions cause mass mortality events of fish. Most of these events go unreported and even when reported it is often several days after the event. This is because dead fish initially sink and only become visible when they float to the surface once gas, produced from microbial decomposition, has built up inside their body. Consequently, the causes of many fish kills remains a mystery.... until now!
Spyvalve uses bivalves to spy on aquatic environments by attaching sensors to their shells to monitor their behaviour. Under normal conditions, their shells are open. This facilitates normal physiological processes, such as feeding, breathing and excreting. When pollution is detected, they close their shell for protection. These data are live-streamed to the network and analysed in the cloud and an alarm produced when all bivalves at a station close for several minutes.
Accessing live data
To access the live-streamed data click on the SpyLocator tab which will take you to a map. Click on a map icon to see the outputs at a station. This will take you to a webpage with all those data. At the top of the page you will see the site name and the bivalve species monitored. Because data are streamed from eight bivalves every minute, the outputs can take 20 seconds to load. In the example below you can see that these data are from Mediterranean Mussels at the Mandurah Marina. Below this is a time slide where you can select the date range over the past two weeks.
Once a time range has been selected, the first graphs are temperature at that station. These are shown as the average over that time on the gauge plot and the temperature each minute over that period on a line graph.
The next figures you see are data from live bivalves at that location. The gauge plot below shows the percentage of time Agent 000 shell was open and the line graph tracks its behaviour over the selected time range. On the vertical axis is valve gape, with 1.00 representing the valves (shells) being open to their maximum extent and values below 0.20 representing shell closure
Benefits of using bivalves to detect stress
Traditionally, aquatic ecosystems have been monitored through measuring
water quality parameters and the values of those parameters
used to infer the effect the water has on its fauna. However, not only is
it impossible to measure every water parameter, but the synergistic effects
of water quality parameters are largely unknown.
Biological monitoring (biomonitoring) has a huge advantage over these
traditional approaches as it measures directly the response by the fauna.
Bivalves also exist in almost all aquatic environments from freshwater
lakes, rivers and estuaries, coastal waters to the deep ocean and from the poles
to the equator. These feature, along with their typical sessile life style, makes
bivalves the best class of fauna for biomonitoring.
Spyvalve uses these bivalves to spy on aquatic environments through sensors attached
to each opposing valve. The sensors measure the amount of electromagnetic energy
between the valves which varies depending on whether the valves are in the open or
closed position. Under normal conditions, bivalves rarely close for longer than a few
minutes.
When all bivalves at a location remain closed for a period of time, an alert is raised
for that location.
Spyvalve´s Advanced Biological Monitoring approach has a wide range of applications.
detect fish kills before they occur
mussel conservation
monitoring and determining success of restoration activities
determine the effects of heat waves on coral reef communities
environmental flows, i.e. the amount of flow required to maintain ecosystem functioning in rivers
can help elucidate the effects of climate change and other anthropogenic impacts on aquatic ecosystems
can be used to determining the suitability of habitats for shellfish reef restoration
to test locations for commercial aquaculture
