Dolphins and Porpoise
We have a number of visitors to the waters around the Dunvegan coast, the most frequent being the Harbour Porpoise, Short Beaked Common dolphin, Bottle nosed dolphin and Minke Whales. Dolphins, porpoise and whales are all marine mammals belonging to the order of Cetacea, which in Greek means ‘large sea creature'. There are 32 different species of dolphin worldwide, the killer whale being the largest of the dolphin family. But there are only 6 porpoise species worldwide.
Dolphins and porpoise are often confused as one and the same, but they are two very different families. Porpoise belong to the Phocoenidae family of cetacean, dolphins belong to the Delphinidae family.
Not all of the visitors will leave open water to come into the Loch in front of the cafe windows, but Harbour Porpoise and dolphins like to make an appearance every now and then.
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Image credit to NOAA Fisheries
Harbour Porpoise
Harbour Porpoise are the smallest of the cetaceans found around the Hebrides.
Adults are between 1.4m and 2m in length with an average weight of 55-75kg, and live up to around 20 years. They usually have dark grey backs and dorsal fins with lighter grey sides and a white throat and belly. Their bodies are small and stocky, as opposed to the long streamline shape of the dolphin.
The small triangular dorsal fin is positioned in the middle of their backs and can be seen as they swim along the surface in an undulating swimming motion. They have small pointed flippers and a stubby head with no beak.
Usually seen together in small family groups of four or five individuals, Harbour porpoise are quite shy and reserved, rarely approaching boats and are not known for frolicking and jumping out of the water, unlike the more active dolphin family.
Porpoise do not use the range of vocal noises common with dolphins. Dolphins make a lot of audible noise as they use their echolocation, and communicate with each other. Porpoise however vocalise at a much higher frequency, higher than the human ear or dolphins can detect. It has been surmised that this higher frequency is a means of communicating with each other, without the predatory killer whales being able to hear. Because humans couldnt hear the vocals of the porpoise it was believed they were silent except for their well know “chuff” noise as they came to the surface to breathe. This gave them the nickname of the “puffing pigs”. Porpoise like the dolphins are highly intelligent
Image credit to NOAA Fisheries
Short Beaked Common Dolphin
Short-beaked common dolphins are one of the most abundant and familiar dolphins in the world. This highly social and energetic species is widely distributed. They grow up to around 2.4m long and weigh around 150kg. They are quite distinctive with their creamy forward flank colouring. They have a dark grey back with a pale cream underbelly. These common dolphins are often seen in quite large active groups, anything from ten to thirty individuals. They are very fast swimmers and highly acrobatic, often leaping high out of the water. This splashing activity can often been seen from quite a long distance away. Common dolphins generally inhabit warm waters. The visitors to the Dunvegan coast are generally Summer visitors, however more recently Common dolphins have been seen throughout the year.
Common Bottle Nose Dolphin
Image credit to NOAA Fisheries
Bottlenose dolphins inhabit the temperate and tropical oceans around the world, with coastal populations entering into bays, estuaries, and river mouths.
As the name “bottlenose” suggests, this species of dolphin has a short, stubby beak. Its sleek body varies in colour from a light to slate grey on the upper body to a pale grey on the underbelly. Scottish bottlenose dolphins are much larger than their more temperate relatives. Growing to a length of 3.9m compared with the usual average dolphin of 2.4m. Weighing in at 400kg when fully grown. Males are significantly larger than females. A curved dorsal fin in the middle of their back, along with powerful, broad flukes on their tail and a pointed flipper on each side allow bottlenose dolphins to swim very quickly reaching speeds up to 22mph.
They have a thick layer of blubber which helps maintain their body heat in cold water and sensitive, smooth skin that flakes off and gets replaced every few hours. Individuals can often be identified by their marks and scars which would have been inflicted through attacks and battles in the past.
Generally dolphins hold their breath for around 7 minutes before having to breathe. A muscular flap covers their blowhole while underwater and opens to exhale once they reach the surface.
Usually seen in social groups of three to ten animals they have complex social structures and hierarchy. Research has discovered that not only are they self aware, they use vocalisations that identify each other. Each dolphin has a vocalised name that is used to call out to each other.
Dolphins produce high-frequency clicks that humans can’t hear. They use these clicks as a sonar system called echolocation. When the clicking sound reaches an object, it bounces back to the dolphin as an echo. Dolphins can process this information to determine the shape, size, speed, distance, and location of the object.
Hebridean bottle nosed dolphins are the most northerly of the species. The Hebridean Whale and Dophin Trust have found that there is a population of around 30-40 individuals inhabiting the Inner Hebrides around Skye.
An excellent source of information for whale and dolphin sightings is through the
Hebridean Whale and Dolphin Trust
A link to their LIVE sighting website is provided below: