"In Search of Giants" Expedition Cruise Report 2025

The second "In Search of Giants" research cruise departed on the 22 August till 1 September 2025.  It was a very exciting trip for rare marine species including outstanding bird sightings.  The intrepid Elizabeth G reached the continental shelf-edge to the west and north of St Kilda, known as the Rockall Trough,  which provided valuable information for future research expeditions. Read the fascinating expedition report from our specialist guide for this cruise, Dr Conor Ryan.

"In Search of Giants" Expedition Cruise Report 2025

In late August, from Elizabeth G we searched the former whaling grounds to the west of the Outer Hebrides. Long sea passages were required to get to the deep abyssal waters to the west of St Kilda. Guests and crew used every daylight hour available to find large whales, which were once hunted here in their thousands to make margarine and petfood.

After a spectacular encounter with around 15 basking sharks to the west of Coll, we anchored in Vatersay on our first night. From there, we were within reach of the shelf-edge, where the seabed drops away steeply from 100m to over 1000m. As we weighed anchor in pre-dawn twilight, coastal bottlenose dolphins (the Scottish ones are the world’s largest) accompanied us until we were clear of the islands.

Our next encounters were bottlenose dolphins of a different kind. At the shelf-edge, near a fleet of Spanish trawlers, we found up to 50 offshore bottlenose dolphins: smaller, darker and shier of vessels than their coastal counterparts. Little is known about this form of bottlenose dolphin, so it was exciting to see them over 100 km offshore. We gathered photo identification images of their dorsal fin markings, to help Hebridean Whale and Dolphin Trust with their research and monitoring.

While low visibility somewhat hampered our search, light winds and a small swell allowed us to spend a few hours scouring the shelf-edge. The visibility did lift occasionally, treating us to a superb mix of seabirds rarely ever seen inshore: Cory’s, sooty and great shearwaters, Wilson’s storm petrel and the very handsome Sabine’s gull. With no land in sight all day and the distinct bird community it was a special feeling to be in the expansive offshore realm.

Approaching St Kilda from the west was a unique experience. We dropped anchor in Village Bay and went ashore the next morning to stretch our legs on Hirta’s idyllic grassy street. The birding onshore was wonderful and included good views of the St. Kilda wren.The highlight for the birders was the barred warbler – a rarely seen early migrant.

Searching to the north and west of the sea stacks of St. Kilda allowed us to take in the sights, sounds and smells of the world’s largest gannet colony, before heading into East Loch Roag. From our anchorage, the standing stones of Calanais were silhouetted by the dusk. The following morning, we walked among the stones and then set off around the Butt of Lewis where we were treated to views of Risso’s dolphins surfing the following seas alongside Elizabeth G.

The bulk of the whale action that we found was around Tiumpan Head, in the middle of the North Minch and the Sound of Raasay. Here we found intense surface-feeding activity by minke whales and common dolphins, with marauding gannets raining down. To see minkes working hard to corral and gobble up shoals of leaping sprat was spectacular. We found a lone fin whale crashing through a bait ball before disappearing, as they sometimes do.

Whale sightings were confined to coastal waters and not on the former whaling grounds. Challenging visibility may have biased this, however future efforts will tell. Using a recently published reanalysis of whaling records, we narrowed down our search area and timed our trip to coincide with the peak in historical blue whale catches around St. Kilda. The last blue whales to be killed here were in 1951, the same year that hunting of the larger whales ceased due to falling meat prices and a dearth of whales. Two whale-generations on, perhaps the large whales may begin to show signs of recovery and return to their former haunts. With more "Searching for Giants"  trips scheduled, we hope to discover sei, fin or perhaps even blue whales that were once so abundant in this region.

Dr Conor Ryan: September 2025