Archipelagos Marine Mammal Team has been monitoring the populations of whales and dolphins in the Aegean Sea and other parts of the NE Mediterranean for over 20 years. This research aims to fill in important knowledge gaps about the populations of these charismatic marine species.

In late August-early September 2019 Archipelagos marine mammal team undertook a very interesting research expedition in the marine region between the islands of Ikaria, Fourni and Samos, in the north Aegean Sea using our research boats “Aegean Explorer” and “Pinelopi”.

During this survey we monitored populations of seven Sperm Whales (Physeter macrocephalus),

we also saw a rare sighting of a small pod of Cuvier’s Beaked whales. Striped dolphins (Stenella coeruleoalba) and Short-beaked Common dolphins (Delphinus delphis) also spotted throughout the survey, in different locations of the whales. Not only did we encounter sightings of all four of these incredible mammals, we also spotted tuna fish and swordfish.

The Sperm whale (Physeter macrocephalus) is the largest species of odontocetes, a class of toothed whales, that are found in the Mediterranean Sea. This population has been listed as an Endangered species by the International Union for Conservation of Nature and Natural Resources (IUCN) Red List.

Female Sperm whales can only give birth to a single calf at a time. Calves can be over 13 feet (4 m) long and while it matures the calf is protected by its mother and other females in the pod. However, calves do not have the capability to undertake deep, long dives like their mothers, so the tight bonds females form allow them to share the responsibility to protect calves at the surface, while some females dive others stay at the surface with the calf.

Using acoustic (hydrophone array system) and observation techniques we successfully heard and had a short observation calf Sperm whale carrying out a neutral behaviour of swimming, in response to our presence. My observations also included BORIS (Behavioural Observation Research Interactive Software) recording these mammals’ behaviours and filling out the behavioural datasheet. We successfully heard the clicks from the marine mammals sighted, with the experience to listen to Sperm whale clicks from three individuals (two adults and one calf).

The team was astonished by an encounter with a calf Sperm whale which lasted an incredible hour, with a life changing opportunity of seeing the calf breach and carry out other behaviours such as, tail out, head out and tail slaps. A true breath-taking encounter that will be cherished in the memories of those who got this experience which will guide future generations to continue our work at Archipelagos.

We are truly amazed by the diversity of this region is, where there is such little protection and management of these incredible mammals and having the opportunity to experience them live in their natural habitat and being able to collect data to create the awareness of their importance and the process to show their need for protection.

Archipelagos Marine Mammals Team will continue this important research aiming to extend our understanding of these charismatic and important mammals, to enable to help and protect them.

Jack Warren