Coastal mammal observations in Scotland

By Michael Demidecki

There cannot be many places where, while one is waiting patiently and scanning the shore line and out lying islands for Otters, a voice announces "Minke Whale". We were at Rhu on Scotland's west coast. It was 28th August 2002 and the occasion was a part of the BNA promoted holiday "Midsummer Mammals" run by Speyside Wildlife.

The sea was flat calm and the sky was a light grey when, later that morning, we boarded our whale watching boat at Arisaig. Within ten minutes we had seen a Minke Whale surfacing, its hooked dorsal fin presenting a clear identification feature, and then diving. Then, great excitement, as our guide spotted through the telescope another whale, this time breaching off the island of Rum, some two miles way. Our boat was soon at full throttle, and we were filled with anticipation of soon enjoying much closer views. As we watched, the whale breached repeatedly, some twenty or thirty times in the next fifteen minutes. On one occasion the whale leapt completely clear of the sea, but at other times part remained still in the water. Minke Whales reportedly do not breach as often as some of the larger whales (and at first until we came close we suspected we were watching another larger species of whale). According to the literature a breach by a Minke Whale, when it does happen, is often repeated two or three times in a row, although larger sequences have been seen. Our sighting therefore was an unusual one, and worth recording in this article.

Minke Whales migrate to the coastal waters of west Scotland every summer to feed on the small fish and plankton. The Minke Whale is the smallest of the baleen (filter-feeding) whales, adults reaching up to 10 metres. Their total lifespan can be 40 to 50 years. Good views were had by us of about six Minke Whales in all, between Arisaig and the islands of Eigg and Rum. Usually we saw just their backs and tail stocks arching strongly as they prepared to dive, without the flukes appearing above the surface. Minke Whales are to be found later in the season also in the Moray Firth (on Scotland's north- east coast), and the first sighting there in 2002 recorded by Dolphin Ecosse (a firm who are based in Cromarty on the Black Isle and who run dolphin watching trips) was on 25th August.

Bottlenose dolphin Photo © Michael Demidecki 2002

The Moray Firth in north-east Scotland, an area of some 5000 square kilometres, is home to a resident population of about 130 Bottlenose Dolphins. This species, which can be found throughout almost all of the world's temperate and tropical seas, reaches its maximum size in British / European waters, the adult reaching a length of some 4.1 metres here, compared for example to some 2.65 metres in Florida, U.S.A. The Moray Firth Dolphins are important because there are only two or three known resident populations along the British coastline, the others being in Cardigan Bay and around the Cornish coast. In the Moray Firth the Dolphins are usually in groups of five to ten, but as many as forty may be seen together. On our boat trip with Dolphin Ecosse in August 2002, we saw one group of 15 females with calves (widely spaced over about half a mile, and with several breaching) with up to four together at any one time; and another group of five males.

At birth, Bottlenose Dolphin calves are a little under 3 feet long. They can swim immediately and are dependent on their mother's milk for around 6 months, but may take the occasional meal of milk until they are several years old. We sometimes saw mother and calf keeping so close together that that the two dorsal fins seemed to rise out of the water together when the animals surfaced. During one watch from the shore (at Chanonry Point on the Black Isle, a good point from which to watch Dolphins as the Moray Firth narrows here and the Dolphins like to feed in the strong currents off shore) we watched, on a rising tide, as a mother and calf sped off towards a large ship that was passing. Looking through binoculars we watched as they leapt into the air in front of the bow wave that the ship was creating.

The Moray Firth is home to other mammals too. About 1200 Harbour (Common) Seals, and Harbour Porpoises are to be found there. On 22.04.02 Dolphin Ecosse recorded a Harbour Porpoise being attacked and killed by Bottlenose Dolphins!

Minke whale Photo © Michael Demidecki 2002

On 24.08.02 along the shore of the Moray Firth we watched a European Otter and two cubs swimming close to the shore. We were informed by a local that this was the first time that year that Otter cubs had been seen there. Perhaps we were witnessing the cubs' very first outing from the holt! While the bitch Otter shallow dived from time to time, the two cubs remained at the surface making continuous excited calls. Unlike in the rest of the UK (where they are generally nocturnal), Otters can be seen in the Moray Firth, as in other parts of Scotland, during the day. The Otter and cubs we saw were first seen at about 11.45a.m.

Further reading:
Bottlenose Dolphins by Paul Thompson and Ben Wilson, Published by Colin Baxter Photography Ltd, 2001, ISBN 1-84107-116-1

Whales Dolphins and Porpoises (Eye Witness Handbook) by Mark Carwardine, Published by Dorling Kindersley, London 1995, ISBN 0-7513-1030-1

Michael Demidecki is a Council memberof BNA and their Hon. Solicitor. Married to Margaret, with a daughter Katherine, he is a keen wildlife photographer and a member of BNA's Hertfordshire Branch.