We Like Mussels - Bob Armstrong's Nature Alaska

https://vimeo.com/478238113

We Like Mussels shows gulls swallowing mussels, sea stars, and urchins whole. Goldeneyes also swallow mussels whole.
Ravens, crows, and oystercatchers also eat mussels but usually break open the shell first and eat the contents.
To learn about gulls that forage extensively on mussels look at DIETARY CHANGES AND POOR REPRODUCTIVE PERFORMANCE IN GLAUCOUS-WINGED GULLS
Also look at https://vimeo.com/298946148
And https://www.naturebob.com/black-oystercatcher-eating-blue-mussels
And https://www.naturebob.com/crows-dropping-mussels
And this article by Mary Willson Surf, bird food and paralytic shellfish poisoning