The dolphin carcass came ashore at Newgale beach in late February, with seals ranging across the sea between south Wales and the Devon and Cornwall coasts considered prime suspects. This incident is part of a broader pattern of seal attacks across British and Irish waters. Earlier in January, witnesses observed a grey seal holding a common dolphin in its jaws in the Irish Sea off Dublin, and Devon waters saw two comparable incidents before the year was out. Seals displaying the same behavior have also turned up across the North Sea as far as the German coastline.
Across the British Isles, researchers have reportedly linked 20 named individuals to this type of attack, each identified through unique scarring on their faces. The concern among scientists is that this hunting technique is not staying within those individuals but spreading. Those 20 animals almost certainly represent a fraction of the total, with Dr Izzy Langley of the University of St Andrews describing the documented figure as a major underestimate.
Historically, Britain's grey seal population has recovered from roughly 500 in the early twentieth century to around 120,000. Scientists trace the roots of dolphin predation to cannibalism, with the behavior first observed in Canadian waters in 1992, off the coast of Nova Scotia. Male seals compete fiercely for mates between September and January, going without food throughout, and studies suggest some seals began targeting pups as a source of sustenance, tearing into the fat beneath the skin and moving on without consuming the rest. Scottish researchers monitoring the behavior over ten years are said to have recorded the rate of grey seal cannibalism doubling and then some between 2015 and 2016.
Seals are no match for dolphins in open water, as dolphins are significantly quicker, raising questions about how seals successfully ambush them. The specific evidence or methodology that led marine investigators to conclusively attribute the dolphin's death to a grey seal attack remains unclear, as does the total number of grey seals estimated to be engaging in this hunting behavior across the British Isles and North Sea. Immediate ecological or conservation impacts from this spreading hunting technique are not yet known, and it is uncertain whether authorities have ongoing measures or plans to monitor or mitigate these attacks.