User blog comment:Lord Loss/Monster Hunter Theory... Blog/@comment-26074976-20130804193415/@comment-4009941-20130804202058

Uhm capcom made the beard thing and it was not trapping air it was a algae and micobes that make oxygen that mainly inhabit its beard.

But I agree with you on some of this as it never did say the limit to how long it can hold its breath from jumping out of the water alone before it gains enough algea.