Maine’s coastal and offshore waters are home to various shark species, a natural component of the marine ecosystem. These fish inhabit both nearshore and deeper offshore areas. Their movements are often influenced by environmental factors and the availability of prey within the Gulf of Maine.
Shark Species Common to Maine
Several shark species inhabit Maine’s waters. Great white sharks, known for their size, are seasonal visitors. These apex predators feed on seals and large fish. Basking sharks, the second-largest fish globally, are also found in Maine. They are filter feeders, consuming zooplankton and small marine invertebrates, and are harmless to humans despite their imposing size, which can reach up to 28 feet.
Porbeagle sharks are found in the Gulf of Maine, often reaching lengths of over 8 feet and weighing more than 450 pounds. These sharks are swift swimmers and feed on squid, bony fish, and smaller sharks. Blue sharks are common in offshore waters during summer months, characterized by their slender bodies and distinctive blue coloration. They primarily consume small fish and squid, growing up to 12 feet long.
Spiny dogfish are abundant small sharks, typically 3 to 4 feet long, known for the spines in front of their dorsal fins. They often travel in large schools and prey on various sea creatures like squid and small fish. Other species like shortfin mako, thresher, and sand tiger sharks are also documented in the Gulf of Maine.
Factors Attracting Sharks to Maine
The presence of sharks in Maine’s waters is primarily driven by ecological factors, including the availability of prey and suitable water temperatures. An increasing population of seals, a significant food source for great white sharks, draws these predators closer to the coast. This natural predator-prey relationship explains why great whites are more frequently observed in areas with dense seal populations.
Seasonal shifts in water temperature also influence shark distribution. Great white sharks, for instance, move south as waters cool. While the Gulf of Maine is experiencing warming waters, the increased shark sightings are largely attributed to successful conservation and fisheries management efforts. These efforts have allowed shark populations, along with their prey like seals, to rebound after historical exploitation.
Understanding Shark Encounters and Safety
Shark encounters in Maine are uncommon, and species in the region are generally not aggressive toward humans. The 2020 fatal shark attack off Bailey Island was the first recorded in Maine’s history, highlighting the rarity of such incidents. Experts suggest that unfortunate encounters often result from sharks mistaking humans for their natural prey, such as seals, especially when a person is wearing a wetsuit.
To minimize the already low risk of an encounter, beachgoers can take several precautions:
Stay close to shore and swim, paddle, or surf in groups.
Avoid areas with seals or schooling fish, as these are shark feeding grounds.
Limit splashing, avoid murky or low-visibility water, and refrain from wearing shiny jewelry.
Avoid being in the water during dawn or dusk, when light is low and sharks may be more active.
Adhere to all beach signage and lifeguard instructions.