Grey seal (Halichoerus grypus)

Grey seal (Halichoerus grypus) (Fig.1) are larger than harbour seal (Phoca vitulina) around 1.8-2.1m in length. They are highly variable in body fur colour, typically dark grey above and pale below with irregular speckling. They have parallel nostrils and a smooth, flat face and muzzle. Habitat for grey seal includes beaches, sandbars and islands. Their diet consists of various fish such as cod, haddock, herring, and sandeel and they will predate upon swimming seabirds and harbour seals (Couzens et al, 2017; NatureScot, 2024).

Population & Distribution:
The global population of grey seal is estimated to be around 400,000 individuals, with 40% of this population found in UK waters (i.e. 160,000) (NatureScot, 2024). Grey seal are a common marine mammal along the East Grampian Coast and they have been recorded at a number of sites including Stonehaven, Aberdeen, Cruden Bay, and Buchan shorelines (SOC North East Scotland Branch, n.d.). 

There are a number of haul out sites along the East Grampian coast, but the largest haul out site is at the Ythan Estuary. The Ythan Estuary was designated as a haul-out site in 2017 after a rise in numbers was recorded at the site (fig. 2-4), and this aims to provide protection for the grey seals from intentional or reckless harassment under the Marine (Scotland) Act 2010 (Scottish Government, n.d.).

There have been very small numbers of grey seals breeding at Forvie NNR since 2016, although more pups are being recorded each year and there is the potential for the Ythan Estuary to become an important breeding site for grey seal in the future if numbers continue to rise (fig. 5).

Conservation Status: 
Grey seal are a Priority Marine Feature, meaning they are of primary concern for marine nature conservation in Scotland (NatureScot, 2020).

Factors Impacting Grey Seal:
The haul-out site on the Ythan Estuary suffers from human disturbance, with a small number of visitors to the site approaching grey seal too closely. This can cause mass stampedes into the sea, impacting on resting behaviour, as well as potentially leading to abandonment of pups. A new car park, boardwalk, and interpretation about the seals has been built  on the opposite side of the Estuary by the Newburgh and Ythan Community Trust, and this is the best place for visitors to see the grey seals up close. 

Report any sightings to NESBReC via the link below.