ORCA Uig-Lochmaddy-Tarbert surveys 2023

A team of up to four trained volunteers including at least one highly experienced observer recorded cetacean sightings using line transect distance sampling methods from a ferry travelling between Uig, Isle of Skye, Lochmaddy, North Uist and Tarbert, Isle of Harris. Two observers searched a 100 degrees area from either side of the ship with a 10 degrees degree overlap on the trackline to satisfy the assumption that all animals on the trackline are detected while one observer recorded data and the other rested. Effort information including location, vessel speed, course of vessel and environmental conditions (sea state, swell, precipitation, glare and visibility) were recorded every 30 minutes when observers rotated or when conditions changed.