The rule for Mussels/cockles etc is if they remain open after tapping them before cooking they are dead and should be discarded then if they remain closed after cooking discard them.
Small crabs can get trapped in them when they close as the tide goes out, must either irritate or tickle the heck out of them but if the above rules are adhered to then there is no issue with eating the mussel. Discard the crabs as they are a bit crunchy . I have never found them in rope grown (commercial) mussels but sand/rock dwelling ones are more likely to have grit or even baby crabs washed into them so a soak in clear seawater will help swill them out.
Great video btw , Rob.
Small crabs can get trapped in them when they close as the tide goes out, must either irritate or tickle the heck out of them but if the above rules are adhered to then there is no issue with eating the mussel. Discard the crabs as they are a bit crunchy . I have never found them in rope grown (commercial) mussels but sand/rock dwelling ones are more likely to have grit or even baby crabs washed into them so a soak in clear seawater will help swill them out.
Great video btw , Rob.