How Do Kingfishers Catch Fish? Diving From a Perch

Step by step: how a kingfisher catches a fish

A common kingfisher hunting along a European river follows the same routine again and again:

1. Watch from a perch. The bird sits on a branch, post, reed or bank, usually 1–2 m (3–7 ft) above the water, with its bill pointing down. Where there is no perch, it can hover briefly over the water instead.
2. Judge the distance. When it spots a fish, it bobs its head up and down. The movement helps it measure how far away and how deep the fish is.
3. Dive. It plunges at a steep angle, wings half folded, and hits the water bill-first. Most catches are made within about 25 cm (10 in) of the surface.
4. Grab. Underwater it opens its wings to brake and snaps its bill shut around the fish like tongs. It does not spear the prey.
5. Escape. It bursts back out of the water bill-first, flaps hard and returns to its perch.
6. Stun and swallow. On the perch it shifts its grip to the tail end and beats the fish against the branch several times. Then it flips the fish around and swallows it headfirst.

Indigestible bones and scales are later coughed up as small gray pellets, a few times a day.

How do kingfishers see fish underwater?

Diving into water is hard on the eyes. Light bends at the surface, so a fish is not exactly where it appears to be from above, and an eye adapted for air sees poorly underwater.

Kingfishers have several solutions:

• Head bobbing before the dive helps them gauge how far away the fish is.
• A third eyelid, called the nictitating membrane, slides across each eye as the bird hits the water. It is transparent, so the bird can still see while its eye is protected.
• Two zones of sharp vision. Each eye has two foveae, the spots on the retina packed with the most light-sensing cells. Kingfishers switch between them as they dive, which helps them keep the target in focus in water. Their underwater vision is not as sharp as their vision in air, but it is good enough to judge where a moving fish is.
• Colored oil droplets in the eye are thought to help cut glare from the water surface.

Clear water matters a lot. Kingfishers hunt by sight, so muddy floodwater after heavy rain can leave them hungry for days.

What fish do kingfishers catch?

Common kingfishers take small fish, typically 2–10 cm (1–4 in) long. The biggest fish are around 12 cm (5 in). In Europe typical prey includes:

When fish are scarce, kingfishers also catch dragonfly larvae, water beetles and other aquatic insects, freshwater shrimps and tadpoles. In winter on the coast they take small marine fish and shrimps in rock pools and estuaries.

How successful are kingfishers at fishing?

Not every dive succeeds. Success rates vary widely with the bird’s experience, water clarity, weather and the type of prey. Adults are much better than juveniles. Young kingfishers must learn to fish within days of leaving the nest, and many fail: they can become waterlogged on their first dives, and a large share starve or drown in their first weeks.

Kingfishers need a lot of food for their size. A pair raising a brood of six or seven chicks has to deliver a steady stream of fish to the nest, so a good territory with clear, fish-rich water is vital. This is one reason why each kingfisher defends its own stretch of river, often at least 1 km (0.6 mi) long.

Do all kingfishers catch fish?

No. The name is misleading. There are more than 110 kingfisher species, and many of them rarely eat fish at all. Forest kingfishers in Africa, Asia and Australia often hunt insects, lizards and other small animals on the ground. The laughing kookaburra of Australia, the largest kingfisher, eats insects, lizards, snakes and small mammals. Read more in is a kookaburra a kingfisher?.

Fishing kingfishers, such as the common kingfisher and North America’s belted kingfisher, share the same perch-and-plunge method. Ospreys use a similar idea on a much bigger scale, diving feet-first rather than bill-first; see how do ospreys catch fish?.

Why the kingfisher’s bill is perfect for diving

The long, straight, sharply pointed bill does two jobs. It grips slippery prey firmly, and it lets the bird enter the water with very little splash or resistance. The shape is so efficient at moving from air into denser water that Japanese engineers copied it to redesign the nose of a high-speed train, as explained in how a kingfisher inspired the bullet train.