Aquatic Warbler
Encyclopedia
The Aquatic Warbler, Acrocephalus paludicola, is an Old World warbler
in the genus Acrocephalus
. It breeds in temperate eastern Europe
and western Asia
, with an estimated population of 15,000 pairs. It is migratory
, wintering in west Africa
. After many years of uncertainty, the wintering grounds of much of the European population were finally discovered in Djoudj National Bird Sanctuary
, Senegal
, with between 5-10,000 birds present at this single site. Its south-westerly migration route means that it is regular on passage as far west as Great Britain
.
This small passerine
bird
is a species found in wet sedge beds with vegetation shorter than . Drainage has meant that this species has declined, and its stronghold is now the Polesie region of south Belarus
, where 70% of the world's population breeds. 3-5 egg
s are laid in a nest in low vegetation. This species is highly promiscuous, with most males and females having offspring with multiple partners (Leisler & Wink 2000).
This is a medium-sized warbler. The adult has a heavily streaked brown back and pale underparts with variable streaking. The forehead is flattened, there is a prominent whitish supercilium and crown stripe and the bill is strong and pointed.
It can be confused with juvenile Sedge Warbler
, which may show a crown stripe, but the marking is stronger in this species, which appears paler and spiky-tailed in flight. The sexes are identical, as with most warblers, but young birds are unstreaked on the breast below. Like most warblers, it is insectivorous, but will take other small food items including berries
.
The song is a fast, chattering ja-ja-ja punctuated with typically acrocephaline whistles.
Old World warbler
The "Old World Warblers" is the name used to describe a large group of birds formerly grouped together in the bird family Sylviidae. The family held over 400 species in over 70 genera, and were the source of much taxonomic confusion. Two families were split out initially, the cisticolas into...
in the genus Acrocephalus
Acrocephalus
The Acrocephalus warblers are small, insectivorous passerine birds belonging to the genus Acrocephalus. Formerly in the paraphyletic Old World warbler assemblage, they are now separated as the namesake of the marsh- and tree-warbler family Acrocephalidae...
. It breeds in temperate eastern Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
and western Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
, with an estimated population of 15,000 pairs. It is migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
, wintering in west Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
. After many years of uncertainty, the wintering grounds of much of the European population were finally discovered in Djoudj National Bird Sanctuary
Djoudj National Bird Sanctuary
The Djoudj National Bird Sanctuary lies on the southeast bank of the River Senegal in Senegal, in northern Biffeche, north east of St-Louis. It provides a range of wetland habitats which prove very popular with migrating birds, many of which have just crossed the Sahara. Of almost 400 species of...
, Senegal
Senegal
Senegal , officially the Republic of Senegal , is a country in western Africa. It owes its name to the Sénégal River that borders it to the east and north...
, with between 5-10,000 birds present at this single site. Its south-westerly migration route means that it is regular on passage as far west as Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
.
This small passerine
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
is a species found in wet sedge beds with vegetation shorter than . Drainage has meant that this species has declined, and its stronghold is now the Polesie region of south Belarus
Belarus
Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,...
, where 70% of the world's population breeds. 3-5 egg
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
s are laid in a nest in low vegetation. This species is highly promiscuous, with most males and females having offspring with multiple partners (Leisler & Wink 2000).
This is a medium-sized warbler. The adult has a heavily streaked brown back and pale underparts with variable streaking. The forehead is flattened, there is a prominent whitish supercilium and crown stripe and the bill is strong and pointed.
It can be confused with juvenile Sedge Warbler
Sedge Warbler
The Sedge Warbler is an Old World warbler in the genus Acrocephalus. It is a medium-sized warbler with a brown, streaked back and wings and a distinct pale supercilium. Sedge Warblers are migratory, crossing the Sahara to get from their European and Asian breeding grounds to spend winter in Africa...
, which may show a crown stripe, but the marking is stronger in this species, which appears paler and spiky-tailed in flight. The sexes are identical, as with most warblers, but young birds are unstreaked on the breast below. Like most warblers, it is insectivorous, but will take other small food items including berries
Berry
The botanical definition of a berry is a fleshy fruit produced from a single ovary. Grapes are an example. The berry is the most common type of fleshy fruit in which the entire ovary wall ripens into an edible pericarp. They may have one or more carpels with a thin covering and fleshy interiors....
.
The song is a fast, chattering ja-ja-ja punctuated with typically acrocephaline whistles.