Firth locally the change is held to be at the Tail of the Bank where the river crosses a sandbar off Greenock at the junction to the Gare Loch, or even further west at Gourock point. However, some firths are exceptions. The Cromarty Firth on the east coast of Scotland, for example, resembles a large loch with only a relatively small outlet to the sea and the Solway Firth and the Moray Firth are more like extremely large bays. The Pentland Firth is a strait rather than a bay or an inlet. These are connected to, or form part of, the
Cromarty Firth seals live here, while minke whales seasonally migrate. Larger animals such as humpback whales, northern bottlenose whales, long-finned pilot whales, common dolphins, large fish such as the sunfish and basking sharks are seasonal or occasional visitors to the firth. The Firth forms one of the safest and most commodious anchorages in the north of Scotland and Invergordon was at one time a major base for the Royal Navy's Home Fleet. The Firth was the scene of the Invergordon Mutiny in 1931. Remnants of the Navy remain, such as the disused airfield near Evanton (now an industrial estate) which was built