The whitetip reef shark (Triaenodon obesus) is a species of requiem shark, a rather fearless but mostly harmless shark we see almost daily while diving Oahu's reefs. Out cruising at times, they spend most of the day resting under coral ledges out of the surge where cleaner wrasse eat parasites off their skin.
Whitetip reef sharks are one of the relatively few species of sharks that can chill on the ocean floor for extended time periods, pumping water through their gills to breathe. This effort requires more energy than effortlessly breathing when swimming. It is suspected the stationary breathing has a somewhat narcotic effect on the shark.
These sharks hunt mainly at night for reef fish, eels, octopus and crustaceans hiding in the coral. The shark's broad, blunt face is designed more for eating right from the reef than catching fish in the open water. The shark's large tubular nasal flaps are highly responsive to the olfactory, acoustic, and electrical cues given off by potential prey.
They tend to be 3-5 feet long (1-1.5 m), making "One-Spot Sue" about as big as they get. She can be identified by the white spot on her side. I've seen only one other larger whitetip reef shark, a massive female stretching just over 7 feet (2.1 m). Not to be confused with their much larger relative, the oceanic whitetip shark, which are responsible for the most attacks on humans, these reef sharks are mostly nonaggressive to divers. However, they do seem sensitive (maybe confused or annoyed) by dive torches, and have bit people spearfishing.
In Hawaiian culture, the loyalty of these sharks to live in areas of the reef for years at a time may have inspired belief in ʻaumākua, the spirits of family ancestors who take animal form and protect their descendants. Likewise, the Hawaiian Green Sea Turtles are also worshipped and cared for as ʻaumākua.
While diving self-reliant, shooting video, I saw One-Spot Sue cruise into this hidden cove. She settled between a smaller reef shark, and one of the largest sea turtles we frequently see here. This century-old female is nicknamed "Queen Kong" as her carapace (upper shell) spans almost 4 feet (1.2 m). #naptime #buddies