Abstract
In 2004 the University of Groningen has started a long-term demographic project on a partly colour-
ringed breeding population of Black-tailed Godwits Limosa limosa in SW Friesland, The Netherlands
(read more on http://www.rug.nl/research/animal-ecology/research/piersma-lab/meadow-birds).
From half December onwards, Black-tailed Godwits leave their wintering areas in West-Africa to their
stopover areas in southern Iberia. Here they are confined to three main areas: Doñana NP and
Extremadura in Spain and the rice fields surrounding the Tejo and Sado estuaries near Lisbon in
Portugal. Resighting color marked birds during the stopover period is necessary for several reasons.
Firstly, if a godwit disperses outside our study area, the chance that it will be resighted elsewhere in
The Netherlands is small. Without the resightings in the stopover area, we would assume that this
individual is dead and therefore underestimate annual survival. Secondly, with enough resightings in
the Iberian Peninsula we can calculate seasonal survival. In other words, we can calculate in which
period mortalities occur more often. Thirdly, by measuring the density of individuals with colour
marks, we can monitor the population size of the western European part of the Black-tailed Godwit
population. Below you will find a summary and detailed day-to-day trip report of our work in
Portugal and Extremadura in 2014.
ringed breeding population of Black-tailed Godwits Limosa limosa in SW Friesland, The Netherlands
(read more on http://www.rug.nl/research/animal-ecology/research/piersma-lab/meadow-birds).
From half December onwards, Black-tailed Godwits leave their wintering areas in West-Africa to their
stopover areas in southern Iberia. Here they are confined to three main areas: Doñana NP and
Extremadura in Spain and the rice fields surrounding the Tejo and Sado estuaries near Lisbon in
Portugal. Resighting color marked birds during the stopover period is necessary for several reasons.
Firstly, if a godwit disperses outside our study area, the chance that it will be resighted elsewhere in
The Netherlands is small. Without the resightings in the stopover area, we would assume that this
individual is dead and therefore underestimate annual survival. Secondly, with enough resightings in
the Iberian Peninsula we can calculate seasonal survival. In other words, we can calculate in which
period mortalities occur more often. Thirdly, by measuring the density of individuals with colour
marks, we can monitor the population size of the western European part of the Black-tailed Godwit
population. Below you will find a summary and detailed day-to-day trip report of our work in
Portugal and Extremadura in 2014.
| Original language | English |
|---|---|
| Place of Publication | Groningen |
| Publisher | University of Groningen |
| Number of pages | 31 |
| Publication status | Published - 1-Dec-2014 |