Short-distance winter movements of mallards (Anas platyrhynchos)

• Research unit: FSVO
• Project number: 1.09.02

Key words (German)

Aviäre Influenza, Stockenten, Winterbewegungen, Risikogebiete.

Key words (English)

Avian influenza, mallards, within-winter movements, risk zones.

Short description (English)

Birds of wetlands and aquatic environments are thought to constitute the major natural reservoir for avian
influenza A virus. However, the role of waterbirds in the spread of highly pathogenic avian influenza A virus
is still unclear. Recent findings suggest that wild birds may be more likely to act as vectors over short than
long distances. Hence, knowledge about short-distance movements of waterfowl is required, in order to assess
the transmission risk between wild birds and poultry.
In Switzerland, mallard is the most common, among the species listed as “higher risk for the spread of avian
influenza” by Wetlands International. Mallards carry a high variety of avian influenza A subtypes and often
feed on land facilitating the contact with poultry. We want to study short-distance movements of mallards
using telemetry in order to 1) assess how far and how often mallards move from waterbodies inland and 2)
determine the environmental factors that influence short-distance movements. The findings of this study will
help to ensure that protective measures for poultry are targeted and effective and in particular will provide a
scientific background for the establishment of risk zones, where measures are taken to prevent contacts
between wild birds and poultry.

Project aims (English)

The goal of the project is to determine how far and how often mallards move during winter and which environmental
factors determine their location. When the environmental factors predicting mallard occurrence are
identified, these factors can then be used as criteria for the assignment of risk zones where protective measures
need to be taken.

Transfer and application (German)

28.05.2008: Umsetzung:

Grundlagen für die Festsetzung von Risikogebieten/Überwachungszonen.  (Selektionssitzung 2008/mvo)

Transfer and application (English)

Similar studies on movements of mallards are being planned or conducted in different European countries
(France: M. Artois, National Veterinary School, Lyon; Germany: Wolfgang Fiedler, Radolfzell; Portugal: D.
Rodriguez, pers. communication). The results of the different studies will help us to improve our understanding
of the importance of mallard as vectors of avian influenza viruses. In particular, this study will provide
scientific evidence on the basis of which risk zones can be established, that has been lacking so far.

Publications / Results (English)

Keller, I.; Korner-Nievergelt, F.; Jenni, L. (2008) Within-winter movements: a common phenomenon in the Common Pochard Aythya ferina. DOI 10.1007/s10336-008-0367-x.

Related documents

• I. Keller, DOI, 2008, 10.1007/s10336-008-0367-x [PDF] 648 kB
• Datenblatt 1.09.02 [PDF] 43 kB
• Datenblatt 1.09.02 [PDF] 41 kB