The aquatic warbler (''Acrocephalus paludicola'') is an
Old World warbler
Old World warblers are 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 ci ...
in the genus ''
Acrocephalus''. It breeds in temperate eastern
Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...
and
western Asia
Western Asia, West Asia, or Southwest Asia, is the westernmost subregion of the larger geographical region of Asia, as defined by some academics, UN bodies and other institutions. It is almost entirely a part of the Middle East, and includes Ana ...
, with an estimated population of 11,000-15,000 pairs.
It is
migratory, wintering in west
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
. After many years of uncertainty, the wintering grounds of much of the European population were finally discovered in
Djoudj National Bird Sanctuary
The Djoudj National Bird Sanctuary (french: Parc national des oiseaux du Djoudj, ) lies on the southeast bank of the Senegal River in Senegal, in northern Biffeche, north east of St-Louis.
It provides a range of wetland habitats which prove ver ...
,
Senegal
Senegal,; Wolof: ''Senegaal''; Pulaar: 𞤅𞤫𞤲𞤫𞤺𞤢𞥄𞤤𞤭 (Senegaali); Arabic: السنغال ''As-Sinighal'') officially the Republic of Senegal,; Wolof: ''Réewum Senegaal''; Pulaar : 𞤈𞤫𞤲𞤣𞤢𞥄𞤲𞤣𞤭 ...
, with between 5,000 and 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 is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...
and
Ireland
Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...
.
This small
passerine
A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped'), which includes more than half of all bird species. Sometimes known as perching birds, passerines are distinguished from other orders of birds by t ...
bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...
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 eastern
Poland
Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populous ...
and south
Belarus
Belarus,, , ; alternatively and formerly known as Byelorussia (from Russian ). officially the Republic of Belarus,; rus, Республика Беларусь, Respublika Belarus. is a landlocked country in Eastern Europe. It is bordered by R ...
, where 70% of the world's population breeds. 3–5
egg
An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the a ...
s are laid in a nest in low vegetation. This species is highly
promiscuous
Promiscuity is the practice of engaging in sexual activity frequently with different Sexual partner, partners or being indiscriminate in the choice of sexual partners. The term can carry a moral judgment. A common example of behavior viewed as pro ...
, with most males and females having offspring with multiple partners.
This is a medium-sized warbler. The adult has a heavily streaked brown back and pale underparts with variable streaking. The forehead is flattened, and the bill is strong and pointed. There is a prominent whitish supercilium and crown stripe.
It can be confused with the juvenile
sedge warbler
The sedge warbler (''Acrocephalus schoenobaenus'') 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 ...
, 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
A robber fly eating a hoverfly
An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects.
The first vertebrate insectivores were ...
, but will take other small food items, including
berries
A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, raspb ...
.
The song is a fast, chattering ''ja-ja-ja'' punctuated with typically acrocephaline whistles.
The genus name ''Acrocephalus'' is from
Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...
''akros'', "highest", and ''kephale'', "head". It is possible that
Naumann and
Naumann thought ''akros'' meant "sharp-pointed". The specific ''paludicola'' is
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
, from ''paludis'', "swamp", and ''colere'', "to inhabit".
Conservation
The aquatic warbler is the rarest and the only internationally threatened
passerine bird
A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped'), which includes more than half of all bird species. Sometimes known as perching birds, passerines are distinguished from other orders of birds by t ...
found in mainland Europe. Apart from a very small remnant population in Western Siberia, its breeding grounds are completely confined to Europe.
The main threat the species is facing is the
loss
Loss may refer to:
Arts, entertainment, and media Music
* ''Loss'' (Bass Communion album) (2006)
* ''Loss'' (Mull Historical Society album) (2001)
*"Loss", a song by God Is an Astronaut from their self-titled album (2008)
* Losses "(Lil Tjay son ...
/
degradation of habitat due to
draining of
wetlands
A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...
, the decline of traditional,
extensive agriculture
Extensive farming or extensive agriculture (as opposed to intensive farming) is an Agriculture production system that uses small inputs of labour, fertilizers, and capital, relative to the land area being farmed.
Systems
Extensive farming is ...
and overgrowing of the species' habitat with reeds and bushes or trees. Under the auspices of the
Convention on Migratory Species of Wild Animals (CMS), also known as the
Bonn Convention
The Convention on the Conservation of Migratory Species of Wild Animals, also known as the Convention on Migratory Species (CMS) or the Bonn Convention, is an international agreement that aims to conserve migratory species throughout their r ...
,
the Memorandum of Understanding (MoU) concerning Conservation Measures for the Aquatic Warbler was concluded and came into effect on 30 April 2003. The MoU covers 22 range States (Belarus, Belgium, Bulgaria, France, Germany, Hungary, Latvia, Lithuania, Luxembourg, Mali, Mauritania, Morocco, the Netherlands, Poland, Portugal, Russian Federation, Senegal, Slovakia, Spain, Switzerland, Ukraine and United Kingdom). As of August 2012, 16 range States have signed the MoU. This instrument provides the basis for governments, NGO's and scientists to work together to save the species and their habitat.
Much of the funding for
habitat protection
Habitat conservation is a management practice that seeks to conserve, protect and restore habitats and prevent species extinction, fragmentation or reduction in range. It is a priority of many groups that cannot be easily characterized in term ...
for this species has come from the EU's
LIFE programme
The LIFE programme (French: L’Instrument Financier pour l’Environnement) is the European Union's funding instrument for the environment and climate action. The general objective of LIFE is to contribute to the implementation, updating and d ...
.
Conservation methods
The main method employed to protect the species from extinction is habitat restoration. Bushes, reeds and trees are cut down. An adequate level of water regulation is achieved through hydraulic equipment installation.
In order to protect the bird's offspring, farmers need to select optimal grassland mowing time (as late as 15 of August) and choose environment-friendly mowing technologies. As the late-cut grass isn't suitable for feeding making these measures economically unfavorable, farmers who agree to help out receive state issued compensations. The unusable late-cut grass is taken to processing plants that recycle it into
biofuel
Biofuel is a fuel that is produced over a short time span from biomass, rather than by the very slow natural processes involved in the formation of fossil fuels, such as oil. According to the United States Energy Information Administration (E ...
/grass pellets.
Translocations
Due to
small and fragmented populations of aquatic warbler within Lithuania, translocation to the
Žuvintas biosphere reserve
Lake Žuvintas is a shallow lake in Alytus district, central Lithuania. Area of Žuvintas Lake is 965 ha. It is the shallowest lake in Lithuania with the greatest depth 3 m and average only 0.6 m. It is a paradise for water birds, but also face ...
in Lithuania became necessary as a method to reverse declining
genetic diversity
Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species, it ranges widely from the number of species to differences within species and can be attributed to the span of survival for a species. It is dis ...
in the region.
During the species' first translocation In June 2018, th
Lithuanian Baltic Environmental Forum(BEF) successfully translocated, raised, and released 49 aquatic warbler chicks from Zvanec Belarus to the Žuvintas biosphere reserve in Lithuania. By the end of the 2019 summer breeding season, 11 (22%) of the translocated birds returned to the Žuvintas biosphere reserve.
In the summer of 2019, the BEF successfully translocated, raised, and released an additional 50 birds from Zvanec Belarus to the Žuvintas biosphere reserve.
Range and population
References
External links
*ARKive
images and movies of the aquatic warbler ''(Acrocephalus paludicola)''BirdLife International The Aquatic Warbler Conservation TeamConserving Aquatic Warbler in Poland and Germany an EU LIFE NATURE projectBaltic Aquatic Warbler an EU LIFE NATURE projectMagni Ducatus Acrola an EU LIFE NATURE projectAgeing and sexing (PDF; 1.3 MB) by Javier Blasco-Zumeta & Gerd-Michael Heinze
{{Authority control
aquatic warbler
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 11,000-15,000 pairs. It is migratory, wintering in ...
aquatic warbler
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 11,000-15,000 pairs. It is migratory, wintering in ...
Birds of Europe
Birds of West Africa
Species endangered by habitat loss
aquatic warbler
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 11,000-15,000 pairs. It is migratory, wintering in ...