A woman has captured the moment a shark swam directly under paddle-boarders in California.

The boarders, who were enjoying a day by the beach near Santa Barbara, were shocked to see the juvenile shark swimming beneath them.

Francesca Nash, who filmed this footage at Santa Claus Beach, sounded shocked but unafraid as she watched the juvenile shark approach her friend's board, before suggesting they move away.

Last week, Santa Cruz declared a four-day ocean ban after a great white shark attacked a kayaker who was paddling beyond the kelp bed on the westside of the city.

The ban, which requires people to remain out of the ocean for a 1-mile radius of coastline between the San Lorenzo River mouth and Fair Avenue, is part of the county's official "Shark Incident Action Plan".

Some people have called for culls to be implemented to curb shark attacks, but there is little evidence to suggest culling is effective.

When culls were carried out in Hawaii between 1959 to 1976, more than 4,500 sharks were killed – and yet there was no significant fall in the number of shark bites recorded.

Many scientists have pointed out that culling sharks is more of an emotional pre-emptive action that makes us feel safer, but doesn't actually protect us.

There are many downsides to shark culling, from moral issues to protecting our oceans. Sharks are essential for healthy oceans because they play a vital role as top predators in the marine food chain.