Dulra Nature Tours show how they use a Secchi Disk to determine how deep light is penetrating in to the water. This gives an indication of the water clarity and how much primary production (plankton) may be present. In turn, this can be related to sightings of filter feeders such as basking sharks.
Thats one ugly man ;)
SOD9627 9 months ago
Great video guys =) helped me with my exam study =D
ElenaFisherFan 1 year ago