Wintering wildfowl in Portugal – 1992-1993

Study Extent

This report was covering from October 1992 to March 1993 of survey.

Sampling

A total of 59 wetlands were considered during the survey, with 19 wetlands as priority areas (with at least 10% of the national total number for the considered species). The time schedule was created following: (1) the counting process with short time scale to avoid overcounting specimens moving between close wetlands; (2) the higher tidal variation to get more wildfowl species in estuaries; (3) the avoidance of hunting days to reduce impact on counting. In estuaries, the counting was performed by boat. In all other wetlands, birdwatchers were distributed to get the best area coverage.

Quality Control

All initial data was inserted in a specific relational database built specifically for the project, which implemented several quality control methods. In the preparation of the dataset for the GBIF publication, data consistency was verified through cluster algorithms using OpenRefine.

Method steps

1. (1) Aggregation of original data from several sources (see above) into a purpose specific relational database built for the project. (2) Preparation of the dataset for GBIF publication used as source the geographic layer in shapefile format. The data layer was a vector layer containing points. The following steps were performed: - Used the WGS84 points to extract the locations from the CAOP2020; - Exported to csv and reinterpreted attributes matching to DwC standard terms.

This dataset is composed by a total of 2484 records of 19 wildfowl species, 10 genera, 4 families: 15 species of Anatidae 1 species of Rallidae 1 species of Phalacrocoracidae 2 species of Podicipedidae

1. Anas crecca
   rank: species
2. Mareca penelope
   rank: species
3. Anas platyrhynchos
   rank: species
4. Mareca strepera
   rank: species
5. Fulica atra
   rank: species
6. Phalacrocorax carbo
   rank: species
7. Tachybaptus ruficollis
   rank: species
8. Anas acuta
   rank: species
9. Spatula clypeata
   rank: species
10. Anser anser
    rank: species
11. Aythya fuligula
    rank: species
12. Aythya ferina
    rank: species
13. Netta rufina
    rank: species
14. Podiceps cristatus
    rank: species
15. Spatula querquedula
    rank: species
16. Aythya nyroca
    rank: species
17. Mergus serrator
    rank: species
18. Tadorna tadorna
    rank: species
19. Aythya marila
    rank: species

Mainland Portugal