Tag Archives: Egretta thula

Little Egret at Ponta Delgada, Flores

SeidenreiherA white bird standing calm near the sea. It is the Little Egret (Egretta garzetta). A small heron. As you would expect from a heron, this bird is beautiful, graceful and shows long legs, neck and beak. A solitary and patient fisherman, the bird is waiting for low tide to make ambushes in still waters on the rocks. On other occasions, the Little Egret risk more and hunt patiently near the surf. As its name indicates this heron is small, of dimensions clearly inferior to Grey Heron (Ardea cinerea) and the Great Egret (Casmerodius albus). Compared with the herons that regularly visit the Azores, only Cattle Egret (Bubulcus ibis) is smaller than the Little Egret.

All its feathers are white and limpid. On the chest they are longer and form a tuft, in a kind of bib. Also on the back of the head you can see two elongated plumes, but only during the breeding season. Its beak is black and straight and the eyes are yellow. The legs are also black, but the toes, quite characteristic, are bright yellow.

In case of doubt in the identification of this species in the field it is to be remembered that both the Great Egret (Casmerodius albus) and the Cattle Egret have the yellow beak. Although the legs are all Continue reading Little Egret at Ponta Delgada, Flores

Vogelfotografie auf Sanibel Island

BraunpelikanHunderte verschiedener Wasservögel säumen die Ufer und suchen nach Nahrung, darunter Nashornpelikane (Pelecanus erythrorhynchos), Braunpelikane (Pelecanus occidentalis), Ohrenscharben (Phalacrocorax auritus), Schmuckreiher (Egretta thula), Kanadareiher (Ardea herodias), Silberreiher (Casmerodius albus), (weiße) Ibisse (Eudocimus albus), Rosalöffler (Ajaia ajaja). Einer der interessantesten Vögel ist der Kleine Blaureiher (Egretta caerulea). Wie ein Gaukler bewegt er sich beim Fischen durch das seichte Wasser, den Kopf in alle Richtungen schwenkend. Mal streckt er einen Flügel aus, mal beide, um das Wasser abzuschatten. Und das alles im Laufschritt. Irgendwann stößt er dann blitzartig zu, häufig mit Erfolg.

Unter Insidern bestens bekannt ist die Möglichkeiten, auf Sanibel Island zu guten Bildern an- und abfliegender Fischadler (Pandion haliaetus) zu kommen. Manche der Masten mit den mächtigen Nestern stehen in den Vorgärten der Bungalows direkt am Meer. Häufig steht im Garten ein alter Baumstamm, auf dem sich der Fischadlerhorst befindet. Hier sieht man während der Brutsaison den Altvogel mit drei oder vier Jungen im Nest sitzen. Der zweite Altvogel fliegt ständig aufs Meer hinaus und kommt mit großen Fischen zurück. Auf der Straße stehen manchmal bis zu zehn Fotografen mit ihren Tele-Kanonen. Gelegentlich zielen sie auch auf Schwarzmantelscherenschnabel (Rynchops niger) und Königsseeschwalbe (Sterna maxima), die direkt am Meer leben Continue reading Vogelfotografie auf Sanibel Island

Bird migration and regional circulation in the Pantanal

Jabiru mycteria, Fazenda Ypiranga, Pocone, Mato Grosso / Brazil

Whereas long-distance bird migration for aquatic bird species is roughly understood there are other movements of birds between especially the lower Paraná River valley wetlands in Argentina, and the south Brazil/Pantanal wetlands which are far from clear.

Besides the fact, that the global patterns of Summer/ Winter north and south of the equator determines the arrival and departure of arctic migrants and Patagonian guests, there are two major inherent factors which drive birds moving in and out the Pantanal. The one is the regular change in flooding and dryness or even droughts. The other factor is the different food mix embedded in that pattern of seasonal flooding. Whereas most birds move in with the floods in September/ October others move in when the floods retreat using food resources e.g. on small pools left after the waters has covered the most part of the Pantanal.

A good example are the Jabirus, Jabiru mycteria, big storks, which are not present in the Pantanal during the flooding season. Obviously they move to higher grounds to sites outside the Pantanal area. Availability of food for the adult individuals to raise their young are the driving factor. The birds prefer low water levels, especially in lagoons and ponds, in order to obtain the food they can catch with their specialized beaks. Besides by watching for preys while walking they also hunt by tactile prey location, thanks to the sensible bill tip. The Jabiru feeds on various aquatic preys such as fish, molluscs, crustaceans, amphibians, snakes, even young caimans and insects.  They walk slowly in shallow water, regularly stabbing and pecking at preys with the bill. One of their fish species preferred are mussum fish (Symbranchus marmoratus), which can stay dormant and encapsulated in the mud throughout the dry season. They are reactivated by the humidity of the rain and start to swim again when the water rises in the rainy season. The Jabiru is a specialist in detecting and catching the dormant fish in the muddy ground of the dried ponds.

Another example of birds using the environmental conditions during the dry season are huge  concentrations in nesting sites in the gallery forest, to take advantage of the seasonal resources available. The breeding colonies are formed by hundreds of nesting birds, such as Wood stork (Mycteria americana), egrets (Snowy Egret, Egretta thula, Great White Egret, Casmerodius albus and the Capped Heron, Pilherodius pileatus) and the Roseate Spoonbill, Ajaia ajaja. In this gallery you will find some more examples of bird moving in the Pantanal or adjacent Southern Brazil or migrate to these wetlands.

In his article in Bird Conservation International, 4, „Migration and other movements among the lower Paraná River valley Continue reading Bird migration and regional circulation in the Pantanal