STOP! Hammertime. While we're fascinated by all marine creatures, the hammerhead shark holds a special place for us as it is the inspiration for our brand and mission.
Get to know these amazing and iconic sharks!
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SCIENTIFIC NAME: Sphyrnidae
TYPE: Fish
GROUP NAME: School, shoal
COMMON NAME: Hammerhead Sharks
There are 9 (True) identified species of hammerheads, most of which are endangered or critically endangered with extinction.
Winghead Shark* (Eusphyra blochii)
Scalloped Bonnethead (Sphyrna corona)
Scalloped Hammerhead (Sphyrna lewini)
Whitefin Hammerhead* (Sphyrna couradi): since 1986, many scientists list this shark as Scalloped Hammerhead (Sphyrnas lewini) however many lists online still show the whiten as a separate species.
Scoophead (Sphyrna media)
Great Hammerhead (Sphyrna mokarra)
Bonnethead (Sphyrna tiburo)
Smalleye Hammerhead (Sphyrna tudes)
Smooth Hammerhead (Sphyrna zygaena)
AVERAGE LIFE SPAN:
Generally, the lifespan for a hammerhead is 20 to 30 years.
Hammerheads give live birth to several pups, sometimes as many as 40! A pregnant hammerhead has a gestation period of about 8-12 months. The shark pups are born in shallower waters and left to fend for themselves, once they grow large enough the young move on to deeper waters.
SIZE:
Between all 9 species, hammerheads top out at lengths between 3-21ft and can weigh over 1,000lbs at the largest!
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DIET:
Hammerheads are excellent at hunting rays. In fact, stingray spines are often found lodged in their head and mouth! Hammerheads prefer hunting in shallow waters, while some species have been known to venture into bays or brackish waters to find prey.
DID YOU KNOW:
Hammerheads have a special muscle that allows them to move their heads up and down; they use their large heads to not only detect prey under the sand but also pin it down, like stingrays, for example.
Hammerheads also prey on lobster, crabs, squid and boney fish species; with reports of cannibalism and one species (Bonnethead) has been known to eat sea grass!
DISTRIBUTION:
Generally solitary, occurring in coastal and semi-oceanic pelagic areas close inshore as well as offshore. Hammerheads’ ranges vary worldwide throughout tropical and warm temperate seas.
Temperate and tropical waters worldwide, far offshore and near shorelines, hammerheads are often seen in mass summer migrations seeking cooler waters. Hot spots include Colombia, Costa Rica (Cocos Island), and Hawaii.
CONSERVATION:
Hammerhead sharks are one of the smallest shark families, with two genera and nine described species; they are also the most threatened family of sharks..
Hammerheads are under threat from bycatch in commercial fisheries as well as shark-finning, the practice of capturing sharks and removing their fins for commercial purposes. Hammerheads are also prized in shark fishing tournaments and negatively impacted by climate change and other human activities - shark cull nets, boat strikes, habitat destruction, etc.
Predominantly living on or near continental shelves has exposed them to extensive overfishing and their nursery habitat of mangrove forest have been significantly depleted in recent years.
Hammerheads are also notorious for high mortality rates after being caught, even if one of these sharks is caught and released, they are known to die shortly after the interaction. Partnered with the fact sharks in general are slow to reach maturity and give birth to relatively few young- their populations are having a hard time bouncing back from the barrage of human-caused threats.
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