THREE SPECIAL VISITS, STAY TUNED

The sun started to rise above the extensive mountain ranges that surrounded Bar Harbour and tuna leapt from the water. The team grabbed their binoculars in amazement that dolphins had been spotted so early on, only to realise it was a fish, not our beloved mammals. The boat cut through the small ripples as we commenced our journey with a Beaufort Sea state of 1 (3 is the maximum that a survey can be carried out.) Each volunteer took half an hour shifts on each quarter of the boat and then rested after 2 hours. You would be surprised that even on a flat sea, focusing on the water proves challenging and even the strongest stomached individual shouldn’t underestimate feeling seasick. It is important to maintain a comfortable and stable position to methodologically scan the horizon for cetaceans. Alas, our first sighting! A dolphin alone, only 10 m away from our boat. My heart stopped, a gleaming arching back broke the surface and then SNAP, photos of the dorsal fin were quickly shot. The next sampling interval, a juvenile appeared close to the mother. We recorded them for a further 15 minutes until the pair dove out of sight. It is likely that the behaviour exhibited is a negative reaction to the boat, despite our research vessels deactivated echolocation device. The experienced cetacean researcher, Elisa, was sure to direct the boat to maintain a suitable distance from the dolphins and to not pursue them as they dove away. The most important data collected from boat surveys are photographs of the dolphins’ dorsal fin to build an ID catalogue to track the residency and migration patterns.

Two hours into the survey, the local sport fisherman guided the boat back through the Adriatic waters and alas Elisa spotted substantially large splashes in the water with her naked eyes. Could it be another dolphin? By now, the sea state was 0 and it was possible to see for miles across a beautifully flat surface. Our boat slowly and cautiously approached. Sure enough, 10 dorsal fins arose from the water in synchrony and swam parallel to our boat. At least two juveniles were spotted in the pod which probably elicited the response of three inquisitive adults to lift their whole face out of the water and enquire about our boat. Each person has a designated role; one member quickly assessed the group type, structure, swim style and behaviour. Just as the survey was coming to an end, a new group of two dolphins appeared in the distance. The water was teeming with life! All the species encountered were the Adriatic subpopulation of the Bottlenose dolphin Tursiops truncatas, among the largest dolphin. These dolphins have a cosmopolitan distribution, excluding the polar regions, and are listed by the ICUN as ‘Vulnerable’. Once abundant and thriving, their distribution is patchy and marked by gaps of low densities because of habitat degradation, overfishing of prey species and organochlorine pollutants from industry. It is therefore vital to record the behaviour of these vulnerable cetaceans and their response relative to pressures such as boat traffic. As we sailed in the harbour, the larger pod of dolphins was recorded displaying full leaps on the horizon.

Nadia Frontier

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