EcoSCOPE
The ecoSCOPE is an optical sensor system, deployed from a small remotely operated vehicle (ROV) or fibre optic cable, to investigate behavior and microdistribution of small organisms in the ocean.
Although an ROV may be very small and quiet, it is impossible to approach feeding herring closer than 40 cm. The ecoSCOPE allows observation of feeding herring from a distance of only 4 cm. From 40 cm, the herrings' prey (copepods) in front of the herring are invisible due to the deflection of light by phytoplankton and microparticles in highly productive waters where herring live. With the ecoSCOPE, the predators are illuminated by natural light, the prey by a light sheet, projected via a second endoscope from strobed LEDs (2 ms, 100% relative intensity at 700 nm, 53% at 690 nm, 22% at 680 nm, 4% at 660 nm, 0% at 642 nm).
By imitating the long, thin snout of the garfish protruding into the security sphere of the alert herrings, an endoscope with a tip diameter of 11 mm is used. The endoscope is camouflaged to reduce the brightness-contrast against the background: the top is black and the sides are silvery. Additionally, the front of the ROV is covered by a mirror, reflecting a light gradient resembling the natural scene and making the instrument body virtually invisible to the animals. A second sensor images other copepods, phytoplankton and particles at very high magnification. Another advantage of these small "optical probes" is the minimal disruption of the current-field in the measuring volume, allowing for less disturbed surveys of microturbulence and shear.
Another video can be seen in the article for Atlantic herring.
An ecoSCOPE was also deployed to measure the dynamics of particles in a polluted estuary: see image on Particle (ecology), another as an underwater environmental monitoring system, utilizing the orientation capacity of juvenile glasseel.
In situ image of feeding Antarctic krill. Visible is a green spit ball and a green fecal string, important components of the biological pump.
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