Bittern
American Bittern
The bitterns ( Botaurinae ) are a subfamily within the family of herons. At the subfamily include a total of 13 extant species in three genera that are distributed almost worldwide and missing only in the very cold regions of the earth. A fourteenth way that black is back bittern, died before 1900. In Central Europe the subfamily with two types, namely represent the bittern and the bittern.
Of the Tagreihern, the most species-rich subfamily within the heron, the bitterns distinguished by a number of morphological characteristics and behavioral traits. The classification into a separate subfamily were confirmed by genetic testing. The South American zigzag heron was counted long time to the subfamily of the tiger herons, is now also expected to bitterns.
Appearance
All species of bitterns are small to medium in size and have 10 tail feathers on. The smallest species of the genus are found in the Least Bittern. The African Graurückendommel achieved, for example, only a body size of 27 to 30 centimeters and weighs 142 grams, which occurs in the Americas American bittern, however, is up to 36 inches tall, but weighs less than 100 grams. The four kinds comprehensive bitterns, however, are medium in size. In the Eurasian bittern females weigh 817-1150, the males 966-1940 grams and reach a body length of 70 to eighty centimeters.
All types is a solid figure with a heron for relatively short, thick neck own. The bill is relatively short and horn-colored, strong yellowish to yellowish - green, and in a few species also blackish green to black. Most species have a brownish plumage. The Graurückendommel and Schwarzdommel have the darkest plumage coloration with its slate-colored brown to black body top. All types have in common that the body base is lighter than the upper side and the front of the chest and neck has brownish longitudinal strips in all species. Only the Mandschurendommel has differing from the other species only a dark longitudinal stripes on.
Distribution, numbers and habitat
Bitterns are represented in North and South America, Asia, Africa, Australia, New Zealand and Europe. Depending on the distribution area are migratory birds. A few populations remain year-round in their breeding grounds. Bitterns are bound in their way of life on the water. Preferred place habitat is dense vegetation belt along freshwater. In particular, the bitterns need extensive reed belt. A Dommelarten also occur in salt marshes and mangroves.
The number of animals of most species of Least Bittern are not clear due to the very secretive lifestyle. The species of the genus, however, been classified by the IUCN as uncritical ( least concern ).
Way of life
The food spectrum of bitterns is very broad and includes fish, crustaceans, frogs, tadpoles, insects and small mammals. The species nest solitarily or in very loose colonies. The breeding season varies depending on the area of distribution. The nest number varies between one and seven eggs.
System
The following species are counted to the subfamily of bitterns:
- Genus bitterns, botaurus South American bittern, botaurus pinnatus
- American Bittern, botaurus lentiginosus
- Bittern, Botaurus stellaris
- Australian bittern, botaurus poiciloptilus
- Genus Little Bittern Ixobrychus Streifendommel, Ixobrychus involucris
- American Bittern, Ixobrychus exilis
- Little Bittern, Ixobrychus minutus
- Chinadommel, Ixobrychus sinensis
- Mandschurendommel, Ixobrychus eurhythmus
- Zimtdommel, Ixobrychus cinnamomeus
- Graurückendommel, Ixobrychus sturmii
- Schwarzdommel, Ixobrychus flavicollis
- † Blackback Little Bittern, Ixobrychus novaezelandiae
- Genus Zebrilus Zigzag heron, Zebrilus undulatus