Marbled Duck Marmaronetta angustirostris Scientific name definitions

The Marbled Duck is a relatively small duck characterized by its black bill, pale-spotted gray-brown plumage, dark eye patch, and the absence of a speculum. It is distributed throughout the central and southwestern Palearctic in several highly fragmented populations that stretch from Central Asia to northwest Africa and the Iberian Peninsula. It is typically found in temporary or semi-permanent wetlands, although it is ultimately tolerant of many types of wetlands, both natural and artificial, provided they offer shallow areas. It tends to prefer brackish wetlands over fresh or saline ones, and well-structured vegetation, especially emergent aquatic vegetation and saltmarsh plants.

As a partially migratory species, it is adapted to spatiotemporal fluctuations in the availability of flooded wetlands, and moves nomadically before and after breeding. Its autumn (August–November) migration is generally southwards, with a northbound return in spring (January–May), but some birds remain in suitable breeding areas during the winter.

The Marbled Duck is a gregarious, non-territorial, non-aggressive, and monogamous species. Pairs are formed each year, starting in autumn (October). Courtship displays, in which several males swim close to one or more females, can be initiated by the male or the female. The species is a late breeder, and northern populations breed even later, with observations of broods ranging from April to September. Nests are constructed by the female and are usually sited on the ground, close to water, under a low shrub or herbaceous cover. It lays one brood per season, and clutch size ranges from 9–14 eggs; larger clutches may include eggs laid by other females, and brood amalgamation can occur. Hatchlings are precocial, nidifugous, and self-feeding. Typically, males abandon females after hatching, but some pairs remain together. Chicks fledge when 50–54 days old. Most aspects of breeding activity, life span, and survivorship of Marbled Duck are poorly known.

An abundant species in the 1800s and first half of the 1900s, the global population of the species has been estimated to range between 15,000 and 61,250 individuals, and additional surveys are needed to gain a better understanding of Middle Eastern and Asian populations. The Marbled Duck is now considered Near Threatened (recently downgraded from Vulnerable), it is endangered by the destruction or degradation of wetlands, illegal hunting and trapping, lead poisoning and pollution, and the spread of invasive alien fish and crustaceans. Conservation measures have prevented the species from disappearing in Spain, but additional efforts are needed in other parts of its range, especially in southwest Asia. It is now extinct in Türkiye.