Shock diving

The impact Diving is the hunting technique of some specialized fish, squid - and shellfish hunters among birds .

In doing so, the bird plunges into the water with partially or fully flung wings and mostly submerges completely. Sometimes the speed of fall is accelerated by wing movements. Depending on the bird species and local conditions, the direction of impact is perpendicular or at a more or less acute angle to the water surface. Shock diving can be done from a slow search flight, from a shaking flight or from a hide above the water. Depending on whether the prey is taken with the feet or with the beak, shock divers dive into the water either with their feet ( ospreys ) or with their heads first.

In order to avoid the penetration of water into the respiratory tract, as with other diving birds, a reflex respiratory arrest ( apnea ) occurs when immersing . Most of the time this hunting method only catches aquatic animals swimming near the surface, but some shock divers, especially the gannets, reach depths of up to 25 meters and more through additional swimming movements under water.

Thrust divers include the osprey , the tern (Sternidae), the gannet (Sulidae), the tropical birds (Phaethonidae), some pelican species such as the brown pelican ( Pelecanus occidentalis ) and most kingfishers (Alcedinidae). Among the songbirds, the dipper (Cinclidae) are the only ones that plunge into the water from low heights in order to search for aquatic insects and other prey on the bottom of the water.

literature

E. Bezzel / R. Prinzinger: Ornithology. Ulm-Stuttgart. 2nd edition 1990. ISBN 3-8001-2597-8