Monitoring fish in multiple aquaria or tanks simultaneously is practical for several reasons. It increases throughput and efficiency, saving time and effort. Add behavioral tracking with EthoVision® XT, and your experiment becomes even more efficient.
For some research purposes, the ability to track animals in aquaria placed side by side is invaluable. For example, when investigating the effect of the presence of a conspecific organism, researchers often use separate aquaria with individual fish placed side by side. The separation eliminates chemical cues from the experiment and prevents physical contact between the individuals. Apparent interaction between individuals can be measured, while preventing possible injury.
Set-up according to your research aims
Depending on the research aim, the video camera is positioned above or in front of the aquaria. From there, EthoVision XT uses the video image (live or from video file), to track each fish as it swims through its aquarium. From that view, you can use EthoVision XT to define zones of interest and use this for data analysis later on.
If you are interested in behavior related to depth levels, use a side view, and with the help of EthoVision XT, divide the aquarium in horizontal zones: upper, middle, and lower. After tracking is complete, EthoVision XT automatically calculates the time spent in each zone, the mean swimming speed and how this differs per zone, etc.
Interested in social behavior? Then use the side view and define vertical zones, for example, the left half of the aquarium being the ‘social side’, and the right half being the ‘nonsocial side’. The percentage of time spent in the zone close to the adjacent aquarium, while the other fish also swims in the social side of its aquarium, can serve as a measure of interaction. If your research requires movement parameters such as swimming speed and total distance swam, a view from the top might be what you need. Again, you can adjust the view and define areas of interest as you see fit.
EthoVision XT offers Trial Control, a useful feature if you want to automatically start tracking as soon as the fish is released into the aquarium. Or at any other point your experimental method requires. In the same way, you can automatically stop the tracking as well. For example, ten minutes after the start or when the animal shows low mobility for five consecutive minutes. Your conditions will be applied to each aquarium individually. By using this cascading start option, you no longer need to worry about putting fish in their aquaria at the exact same time.