On 19 July 2019 an estimated 20 bottlenose dolphins (Tursiops truncatus) were observed in the Marsdiep, a tidal inlet connecting the North Sea and the Dutch Wadden Sea, between Den Helder and the island of Texel. Photographs and video recordings were made and nine individuals were matched with known dolphins from the Moray Firth, NE Scotland. These are the first matches of this east coast of Scotland population outside the UK and Ireland. Subsequent observations of individuals from this group show that at least some of the animals have returned to Scottish waters, while others were photographed in Danish waters. Furthermore, we report on a photo identification match of a solitary bottlenose dolphin between France and the Netherlands. These matches suggest that bottlenose dolphins, in the Netherlands, originate from two different genetically distinct populations: ‘Coastal South’ and ‘Coastal North’. This evidence of previously unknown long-range movements may have important implications for the conservation and management of this species in European waters.

In the present study, short-beaked common dolphins (Delphinus delphis L.) from the Bay of Gibraltar (GIB) and the Moray Firth (MF) were examined to document the relative frequency, distribution and shape of dorsal edge markings (DEMs) in the species and investigate potential causes for their occurrence. A dorsal fin layout system was used to map the relative positions and shapes of presenting DEMs along the anterior/posterior and upper/lower fin margin from 617 animals. A total of 1989 DEMs were extracted from the combined datasets, with individuals exhibiting between one and 11 nicks (median = 3). DEMs (in the form of tears, nicks, notches and indents) were primarily observed along the posterior trailing edges of fins, with the highest concentration being recorded in the upper region of the posterior fin (80.3%). Approximately 80% of all DEMs were round or rectangular in shape. Square (notched) and indented nick shapes were further recorded, but in significantly lower numbers. In contrast to all other nick shapes however, indented DEMs predominantly occurred along the anterior fin margin. Both natural and anthropogenic sources were implicated as causes of DEMs in the dataset. Interactions with fisheries were apparent in both GIB and MF animals and evidently present a threat to both populations. Indeed, the occurrence, prevalence and type of presenting DEM and/or fin injuries (e.g. missing fins or disfigurements) in the species may provide a useful measure of the type and intensity of fisheries interactions affecting different populations.

This paper describes a rare sighting of an anomalously white harbour porpoise (Phocoena phocoena) in the coastal waters of the outer Moray Firth in north-east Scotland. The recording provides the first photographs of such an individual from the northern North Sea. At an estimated body length of 1.5 m, the present animal had evidently survived to adulthood, in spite of its condition, confirming the potential longevity of such hypo-pigmented individuals in the wild. Further recaptures of this naturally-marked animal may provide valuable information on the site fidelity and long-term spatial movements of these notoriously difficult to study cetaceans.

The short-beaked common dolphin (Delphinus delphis) is regarded as notably rare or absent from the northern North Sea, but recent evidence suggests a rising frequency of the species in these waters with increasing regional sea temperatures. The following paper documents the presence of D. delphis in the Moray Firth in north-east Scotland and provides the first evidence for the sustained occurrence of these delphinids in this region during the warmer summer months at least. Sightings were collated during systematic surveys of the outer Moray Firth between 2001 and 2009 by independent research teams from the CRRU and WDCS. A total of 13 encounters (with group sizes ranging from 2 to 450+ animals) were recorded with the species across this period, the first of which was in June 2006, with annual encounters being logged thereafter between the months of May and August from 2007 to 2009 inclusive. The animals were recorded in water depths of 51 to 209 m (mean depth: 88.6±42.2 m) and at a distance from shore of 5 to 32 km (mean distance: 16.6±8.0 km). New born calves were observed in June and July, and photographic recaptures of identifiable ‘marked’ adults were determined in 2009. The consistent presence of common dolphins in the outer firth post 2005 and the recapture of recognizable individuals suggest a comparatively recent colonization of these waters by the species over a relatively short period of time. The impacts resulting from such a range expansion upon the existing cetacean community and the subsequent implications for management are discussed.

On 25 March 2008, a stranded Cuvier's beaked whale was discovered on the southern coast of the Moray Firth in north-east Scotland. Whilst strandings of the species are not uncommon in Scotland, the vast majority occur along the Atlantic coasts to the west of Scotland and Ireland. By comparison, records from the North Sea coast are notably absent, and this event is believed to be the first documented stranding of a Ziphius cavirostris from this mainland coastal region until now. Due to the severe state of decomposition of the specimen, no necropsy was made and therefore the cause of death could not be determined. However, this event may have been linked to a number of other beaked whale strandings in Scotland at this time. Whilst the North Sea region is considered to be an entrapment area for several species of oceanic whale, the Cuvier's beaked whale is rarely thought to travel far enough north to enter this trap. However, the phenology of these and other recent Cuvier's beaked whale strandings would suggest a possible northern range expansion for this species in UK waters, which may explain the increasing number of incidental events now being observed.