Hawaii’s marine environment is a vibrant ecosystem supporting a diverse array of life, including a significant population of sharks. These apex predators play a role in maintaining the health and balance of ocean populations by preying on the sick and weak. Understanding shark presence and behavior in Hawaiian waters is important. While many species inhabit the surrounding seas, only a few are regularly encountered in nearshore areas.
Native Shark Species in Hawaiian Waters
Over 40 species of sharks inhabit Hawaiian waters, though only about eight are commonly found in nearshore environments. Among the most frequently encountered are reef sharks, such as the whitetip reef shark and the blacktip reef shark. Whitetip reef sharks are typically slender, gray, and characterized by white tips on their dorsal and tail fins, usually measuring under 5 feet in length. They are often observed resting in caves or under ledges during the day. Blacktip reef sharks are recognized by the distinct black tips on their fins and are frequently seen in shallow lagoons.
Sandbar sharks are another common species, identified by their tall, triangular dorsal fin and a sleek, gray-brown body. These sharks can grow up to 8 feet long, though they are generally under 6 feet in Hawaii, and are known to be generally docile around humans. Tiger sharks, recognized by their blunt snout and the vertical bars on their sides which fade with age, are among the largest species, potentially reaching 18 feet in length. They are opportunistic feeders with a varied diet.
Scalloped hammerhead sharks are also present, distinguished by their unique hammer-shaped head with a central indentation and often seen in schools. These sharks can grow up to 13 feet, with an average of 6-8 feet in Hawaii, and are generally considered shy. Galapagos sharks are robust sharks that can reach up to 12 feet in length and are frequently sighted, particularly off the North Shore of Oʻahu. They are known for their curious but often non-aggressive behavior towards divers.
Typical Habitats and Prevalence
Sharks are distributed across various marine environments in Hawaii, from shallow coastal reefs to the deep open ocean. Whitetip reef sharks typically inhabit shallow reefs and lagoons, often staying in specific areas for extended periods. They are commonly found at depths ranging from 25 to 130 feet near coral reefs, where they can be observed resting in underwater lava tubes or under ledges. Blacktip reef sharks also prefer shallow reef areas and lagoons, sometimes with their dorsal fins visible above the water surface.
Sandbar sharks are predominantly found in shallow coastal waters, including around continental shelves, river mouths, sandy flats, and estuaries, often at depths between 30 and 900 feet. While they frequent shallow areas, they tend to stay beneath the surface. Tiger sharks have a broad distribution, occupying the entire water column in coastal environments and moving between the surface and depths of about 2,500 feet in pelagic waters. They are often attracted to stream mouths after heavy rains and areas frequented by fishing boats.
Scalloped hammerhead sharks are found in both coastal and pelagic regions, with adults typically living offshore and coming into shallower areas like Hilo Bay, Kaneohe Bay, and Waimea Bay for pupping. These sharks can be found at depths up to 900 feet. Galapagos sharks prefer coastal and island slopes, which are abundant around the Hawaiian Islands.
Understanding Shark Encounters
Shark encounters in Hawaii are rare events, despite the common presence of various shark species in the waters. The average number of shark incidents per year is approximately 5.8, with most being non-fatal and often involving surfers or swimmers in deeper waters. Over the past 43 years, from 1980 to 2024, Hawaii recorded a total of 177 shark attacks.
Maui has seen a higher number of incidents compared to other islands, with 62 incidents between 1995 and 2022, potentially due to its expansive insular shelf providing an ideal habitat for tiger sharks. Most shark attacks occur between September and November, which coincides with the migration of mature tiger sharks and pupping season. While tiger sharks are thought to be responsible for most incidents in Hawaii, they are known to bite people at any time of day.
To minimize the risk of encounters, consider the following:
- Swim with others and avoid swimming alone.
- Stay out of the water at dawn, dusk, and night, as these are peak feeding times for many shark species.
- Avoid murky waters, harbor entrances, and areas near stream mouths, especially after heavy rains, as these areas are frequented by sharks and reduce visibility.
- Avoid wearing high-contrast clothing or shiny jewelry and refrain from excessive splashing, as these can attract sharks.
- If a shark is sighted, calmly and quickly leave the water and alert others.