I fished have Chesil Beach for over 30 years and regularly used to see whitebait jumping out of the water when a shoal of mackerel(what is that?) went past, some times 5 or 6 shoals would go past in a session.
I has been less common more recently as it is unusual to see a shoal of mackerel off there these days
I used to pick up the whitebait and take home as an extra bonus
Tony