It’s because they are ignoring him (as per the running gag from a few previous comics). He doesn’t understand how they can ignore him so well without hoods to block their peripheral vision.
The only way it would take 12 hours for the tide to go out… is if it was already out. It’s ~12hr 25min between low tides. Not sure if that makes it funnier or sadder.
http://taronga.org.au/animals-conservation/conservation-science/australian-shark-attack-file/latest-figuresThe statistics do indicate hundreds of shark attacks. Over the last 100 years. According to the linked site, we get about 8 attacks total a year. In comparison, nearly 300 people die from drowning every year in Australia. The water is more dangerous than the sharks.
Definitely not travelling sailsmen