A simple and inexpensive device to measure immersion times in wave exposed shores

An inexpensive and easy to build and deploy device to measure immersion times is described. The device consists of an LCD timer mounted in a small waterproof PVC housing. Time is recorded and integrated when seawater creates a connection between two stainless steel contacts. The device was tested in the laboratory and under field conditions on a wave swept shore. Under laboratory and field conditions, the device gave precise estimates of immersion times with maximum error of less than 4%. Applicability of this device in ecological and physiological studies is discussed and compared to other methods proposed in the literature.