Humans are the most dangerous ocean reef predators. Humans have been polluting and over fishing in the oceans for years. Boaters have killed and destroyed parts of the reefs and the animals that call the reefs home. Scuba divers "collect" parts of the reefs for their personal salt-water aquariums and souvenirs Marine biologist also prey on the reefs and its marine life for research purposes. Even Charles Darwin had a hand in this practice. Research or not it's still a predatory practice and it causes damage to the reefs and the animals that live there.
The second largest reef predator are killer whales they eat smaller whales, sharks, manatees, seals and any fish or mammal that crosses there path.
The sharks have a large predatory role in the reefs as well. Simply put a shark will eat anything that does not eat it first.
In addition, the process continues with the next larger fish or marine mammal if it is smaller than them they will prey and eat it.
It is called the ocean food chain; large animals eat the smaller ones and it continues down to the tiny organisms of life that make up the reefs.
Now lets look at a different angle humans spent a lot of time in the ocean surfing, scuba diving, fishing and snorkeling taking photos of the beautiful reefs and animals that habitat it. The most dangerous reef predators for humans most would believe is a shark. Which is incorrect sharks do not like the taste of humans when a shark attack occurs it is strictly accidental. A shark will taste its "meal" before eating it so your shark attacks are simply a sampling unfortunately once sampled by a shark the damage is already done. I have done extensive research on sharks, there eating preferences, and if you notice when you hear of a shark attack the shark does not return to the victim to finish them up. According to the National Marine Institution 99% of the time when a shark attacks a human it is because they have mistaken them for a seal or other large animal or they are attracted to the human because of the colors they are wearing or the smell of blood. Sharks can be lazy and prefer to eat something that is already dead.
I would like to share the seven most dangerous reef predatory to not only other ocean life but to humans as well.
The Lion Fish is a yellow and brownish color with several long needles like spines sticking out of both sides of its body. They can grow up to two feet long. There spines are venomous and they are deadly to there prey. To a human it will make you very sick and if medical treatment is not sought soon enough it could be fatal. The most dangerous threat for a human is one of the needle spines puncturing a vital organ.
The Stonefish is very small and blend in well with the colors of the reef they have sharp spines that when attacked inject a poisons venom into there prey and it is fatal to humans as there is no anti venom available.
The Irukandji Jelly Fish a small fish with four toxic tentacles one on each corner of there body. The toxin kills its prey in a less than 5 minutes and a human in about 30 minutes. Medical treatment can prevent death in humans.
The Box jelly fish just as it name implies it is the shape of a small box with a group of several toxic tentacles attached to each of the corners of it's body, it's estimated the Box fish has over 60 tentacles. This fish stings several times at once using as many of its tentacles as possible. Fatal to it's ocean prey and is fatal to humans.
The Blue ringed octopus is an ugly little brown and red colored animal that when threatened has a blue ring that glows around its body. The ring glows as a warning when the octopus feels threatened and it makes this octopus unique looking divers have found out the hard way that it is not to messed with it's toxic venom will kill a human in less than five minutes.
The Cone Shell fish is a very pretty small fish that looks exactly like a colorful cone seashell you would find on the beach. Unfortunately, they have Nero toxic venom that is deadly and one bit can kill hundreds of humans.
The Sting Ray is not normally considered a threat to the curious underwater humans however as a fan of the late great Steve Irwin (Crocodile Hunter) I fell the need to include this animal as Steve meet his fate when a stinger on the rays barb tail puncture a hole through Steve heart killing him.
All ocean animals should be treated with the utmost respect and one should be cautious although they are beautiful and amazing creatures and the most dangerous can be very small and seemingly harmless you must remember you are in there habitat and you are seen as a threat to them.