Ducks are semi-aquatic birds with strong motivational drives for water immersion and bathing, yet the majority of commercially farmed ducks in Europe have no access to open water, creating endemic behavioral welfare problems.
The strong motivation for water access in ducks means that its denial causes behavioral frustration that is expressed as vacuum bathing - performing the bathing motions without water. This is a welfare indicator equivalent to stereotypic behavior in mammals. Ducks without water access have dirty plumage, eye problems, and reduced ability to perform normal preening behavior. Providing adequate water is the single most important welfare improvement for farmed ducks, yet it is not legally required in most jurisdictions. The foie gras production system involving force-feeding causes acute stress and liver disease in ducks and geese - a practice widely condemned by veterinary welfare scientists.