The cattle egret’s dependence on domestic stock to flush insects, as an alternative to wild herbivores, brings it into a familiar relationship with human beings. And many of the arboreal colonies of heron and stork species in Africa are in or near villages. Abdim’s stork ( Sphenorhynchus abdimii), for instance, will nest on native huts in a treeless area. The association of the white stork (now an endangered species) with humankind in its preference for nesting on buildings is further mentioned below, but it is not the only species thus involved. At one time a number of species of little egrets were persecuted at their breeding places for the sake of their nuptial plumes-aigrettes (or ospreys)-but such killing has now largely been stopped. They are not sought by humans, and many are protected. Get a Britannica Premium subscription and gain access to exclusive content.Īlthough some freshwater fishing interests may regard herons as undesirable competitors, on the whole the members of this order are considered to be either beneficial or neutral in respect to the economy. Several other ibis species are rare and are declining in population. At the other extreme, the Japanese ibis ( Nipponia nippon) is on the verge of extinction, only one small colony being known. Many of the species in the order are very abundant, with world populations running into millions, and some assemblages, such as those of the lesser flamingo ( Phoeniconaias minor) in Africa, are enormous. The flamingos require brackish or alkaline water, and two species inhabit Andean lakes at elevations of up to about 4,000 metres (13,000 feet). The usual habitat of ciconiiforms is near water, chiefly fresh, and only a few species, such as the white stork ( Ciconia ciconia), live largely on dry ground. The flamingos are found throughout the tropics but are not represented in the Australasian region. The ibis are widely distributed but are not found in New Zealand. The typical storks (subfamily Ciconiinae) are not represented in North America and have only one species in the Australasian region the wood storks (subfamily Mycteriinae) are represented by one species in the New World and three in the Old World. The shoebill ( Balaeniceps rex) has a limited distribution in tropical Africa, and the hammerhead ( Scopus umbretta) is almost confined to that continent. The herons are the most cosmopolitan family, some being found even on remote oceanic islands.
Some of those breeding in the North Temperate Zone perform long migrations. Distribution, habitat, and abundanceĬiconiiforms are found throughout the world, except in the polar regions, but the largest number of species are found in the warmer parts. Each of the remaining two families contains a single species with some peculiar characteristics. The herons are more diverse, with a greater size range, the bitterns standing a little apart in behaviour more than in structure. The ibis form an even more homogeneous group, birds of medium size with markedly downcurved, slender bills the spoonbills, of the same family, differ in this respect, as the name implies. The storks, even including the wood storks, form a recognizable group of birds of from medium to large size. With the partial exception of the flamingos, the structural characteristics of the order are well marked, and the same is true of the families. SpaceNext50 Britannica presents SpaceNext50, From the race to the Moon to space stewardship, we explore a wide range of subjects that feed our curiosity about space!.Learn about the major environmental problems facing our planet and what can be done about them! Saving Earth Britannica Presents Earth’s To-Do List for the 21st Century.Britannica Beyond We’ve created a new place where questions are at the center of learning.100 Women Britannica celebrates the centennial of the Nineteenth Amendment, highlighting suffragists and history-making politicians.
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