The aquatic warbler uses a very particular type of habitat as nesting place : wetlands with low vegetation and shallow waters, called "sedge fen mires".

These ecological requests are found in meadows of seasonal flooding and in wetlands. They are composed by helofitic species of low or medium size such as sedges (Carex), Iris, Cladium mariscus, Molinia caerulea, reed, sometimes combined with sparse bushes of willow genus.

The aquatic warbler has a complex reproductive system which combines polygyny and promiscuity, which explains that more than 60% of the egg-laying is fertilized by between two and four different fathers.

The females are the only ones which are responsible for the care and breeding of the offspring, so that the nesting areas have to shelter abundant populations of different arthropods species to permit of bringing up the broods.

During the migration, the species also use wetlands with helofitic vegetation and river edges with marshy and bushy vegetation.

The aquatic warbler is a transaharan migrator which autumnal migration is concentrated in countries of northern and central Europe, its presence being regularly recorded in Germany, Holland, Belgium, France and United Kingdom.

The available information about its winter ranges is very scarce. They are situated in a large area in western Africa, in the South of the Sahara desert. In these zones, the habitat occupied by the aquatic warbler is also similar to the breeding areas : flooded grasslands, reedbeds and formations of glasswort.