Careless nurse

Found this cluster of egg sacs on the beach, tangled inextricably together but fairly fresh, the leathery cases still pliable and bulge of the fish embryos palpable inside. They were about 4 inches long.
Someone in the Facebook Beachcombing group (so useful these communities of specialists and knowledgeable amateurs) identified them as the eggs of a nurse hound, a large dogfish  that like all members of the shark family is oviparous, i.e. producing eggs that hatch outside the mother's body. But sadly not these babies.

However I have reported their existence to the Shark Trust who run an egg case recording project so if you do find any log them on the website, or you can at least use their ID chart to decide what you've found. North Atlantic sharks (skates, rays and dogfish) are declining in numbers and it's important to collect these records.