Fish
Needlefish
Tylosurus crocodilus · also called needlefish, houndfish, crocodile needlefish
The needlefish is a living javelin: a metre or more of thin silver fish that swims right at the surface with a beak full of fine teeth. It is harmless while it stays in the water. The problem is that when it is startled — by a boat, or a light at night — it hurls itself out of the sea at highway speed, and it has impaled, and occasionally killed, people who were in the way.
Overview
Needlefish live in warm coastal waters worldwide, in the top few centimetres of the sea over reefs, lagoons, and open shallows. The largest species reaches 1–1.5 m, with an extremely elongated silver body and long, tooth-lined jaws. They hunt small fish at the surface.
The leap
Frightened — especially by a bright light at night or an approaching boat — a needlefish rockets out of the water, skimming through the air rigid and straight at around 60 km/h.
A real hazard
Because it leaps toward lights and moving boats, a needlefish regularly strikes people, driving deep puncture wounds into the arms, chest, neck, or eye, with the beak tip often snapping off inside the wound. In parts of the Pacific where people fish at night from small boats, needlefish injuries are common and there have been deaths, and local fishers rate them more dangerous than sharks.
Green bones
Needlefish bones are stained vivid blue-green by a harmless bile pigment. The fish is good to eat, though the colour puts some people off.
Status
The needlefish is Least Concern, common and widespread.
Needlefish: common questions
Are needlefish dangerous to people?
They can be, in a specific way. Needlefish are not aggressive and have no interest in attacking humans, and their teeth, while sharp, are small. The danger comes from the leap. A needlefish that is startled at the surface launches itself out of the water in a fast, flat trajectory, and if a person happens to be in the way, the fish's hard, pointed beak can punch several centimetres into the body. Injuries to the hands, arms, and torso are usually survivable, but strikes to the neck, chest, or eye have caused serious harm and, in a number of documented cases, death. The beak frequently breaks off and has to be removed surgically.
Why do needlefish jump toward boats and lights?
It appears to be an escape response gone wrong. A needlefish at the surface reacts to a sudden disturbance by accelerating away from it, and part of that response is to break clear of the water, which lets it move faster and dodge unpredictably. At night, artificial lights on boats, headlamps, and lanterns seem to disorient the fish or to draw it in, perhaps because it associates surface commotion and light with prey, and it may then launch toward rather than away from the source. The result is that people night-fishing from low boats and canoes are the ones most often hit.
Do needlefish really kill more people than sharks in some regions?
In certain island communities of the Pacific, statistics kept by clinics and researchers have shown more injuries and occasionally more deaths from needlefish than from sharks over the same period. This is not because needlefish are especially deadly, but because so many people spend nights on the water in small, open craft with lights, exactly the situation that provokes the leap, while serious shark encounters are rare. It is a good illustration of the general point that the animals most dangerous to a particular group of people are often not the ones with the fearsome reputation.
What is the difference between a needlefish and a gar?
They look alike, both being long, slender, surface-oriented fish with beak-like jaws full of teeth, but they are not closely related and the resemblance is convergence on the same body plan. Needlefish are marine and brackish-water fish of the family Belonidae, related to flying fish and halfbeaks, with a light skeleton and green bones. Gars are heavy-bodied freshwater fish of North and Central America, an ancient lineage with thick, armour-like scales and a hard, bony body. A needlefish is built for speed at the surface of the sea; a gar is a slow ambush predator of rivers and lakes.