Buzz
Along Australia's eastern coastline, an unusual behavior has been observed in fish. Biologist Ryan Day witnessed needlefish employing a unique hunting strategy, propelling themselves out of the water to strike their prey mid-air on two separate occasions.
Day notes that, to his knowledge, “this marks the first documented instance of a fish leaping from the water to prey on other fish.”
Needlefish, often referred to as Long Toms, are aptly named. Their elongated, slender bodies and lengthy jaws filled with sharp teeth make them formidable. They primarily inhabit and feed near the water's surface and are renowned for leaping out of the water to evade predators. Capable of reaching speeds of around 40 miles per hour, they can even glide across the water's surface on their tails. Day highlights that their tendency to go airborne has led to serious injuries and fatalities among people struck by needlefish during boating or swimming activities.
While observing needlefish hunting small baitfish near Australia’s Heron Island, Day noticed the fish utilizing their leaps in a new way. After stealthily approaching their prey, some needlefish followed their usual method, swimming through the baitfish school before lunging at a specific target.
However, other needlefish adopted a different strategy. As Day and his team report in the Journal of Fish Biology, these fish executed “leaping attacks,” propelling themselves out of the water and diving back into the center of the baitfish school to capture their prey. These aerial attacks were not rare, making up half of the observed hunting attempts.
The same behavior was recorded during fieldwork near North Stradbroke Island. Here, the needlefish launched themselves from the crests of waves, seemingly using the wave energy to enhance their forward momentum.
The biologists propose several reasons for this airborne hunting strategy. First, it significantly extends their striking range. Typically, needlefish lunge at prey from about 1.5 feet away, but at Heron Island, they initiated attacks from six feet away, quadrupling their range. This allows them to strike faster and from a greater distance, reducing the prey’s chance to escape.
Aerial attacks also eliminate a key escape route for the prey. When attacked underwater, baitfish often leap out of the water to evade capture, mimicking the needlefish’s own escape tactic. However, attacks from above block this option, forcing the baitfish to scatter and dive deeper.
Another possibility is that needlefish leap out of the water to conceal themselves from their prey. Due to the refraction of light as it transitions from air to water, a fish looking upward sees the sky compressed into a narrow circle, known as Snell’s Window. Beyond this window, the surroundings appear dark or reflective, mimicking the ocean’s depths. Objects directly above are clear and full-sized, but those near the window’s edge seem smaller, dimmer, and distorted. This optical illusion makes objects appear farther or harder to detect. Researchers suggest needlefish exploit this phenomenon, leaping into the air to vanish from their prey’s view just before striking.
Needlefish aren’t alone in leveraging Snell’s Window or the open sky. Flying fish, their relatives, are famous for leaping out of the water at shallow angles to evade predators by hiding near the edges of this optical phenomenon. While needlefish are the first documented to use aerial attacks on aquatic prey, other fish also leap to catch airborne prey. For instance, scientists in South Africa recently recorded tigerfish launching themselves out of the water to snatch birds in mid-flight.
