The UK is home to two species of seal, the grey seal and the smaller harbour seal.

In some areas of Scotland, harbour seal numbers are in decline or are at drastically depleted levels compared to 20 years ago.

SMRU aerial surveys revealed harbour seal numbers in The Wash (southeast England), the main population centre in England, are ~25% lower than in 2018. This large embayment has regularly been home to around 5,000 harbour seals, when surveys began in 1988 and as recently as 2018. University of St Andrews Sea Mammal Research Unit (SMRU) are undertaking a programme of work to understand the decline.