NIJLAND F (2000) A closer look at territory mapping Common Snipes Gallinago gallinago . LIMOSA 73 (1): 1-6.

In a Frisian meadowbird reserve (182 ha) near Leeuwarden the breeding population of Common Snipe was censussed in 1991-96, using the Dutch version of the territory mapping method (BMP). Snipe observations were classified according to the birds' behaviour: 1) single local birds; 2) pairs; 3) territorial behaviour: drumming display flights, chippercall (in flight or sitting), wing-arch flights and aerial duels; 4) observations indicating a nest and 5) parents, apparently with chicks nearby. Pairs, nests and parents with chicks were rarely observed. Observations of single local non-migratory birds predominated in April and early May. Observations of territorial behaviour and observations indicating a nest or chicks nearby were made throughout the period with peaks in the first half of May and in June (fig. 1). The portion of drumming display flights decreased during April-June (fig. 2), while the chipper-call, wing-arch flights, aerial duels and observations indicating a nest or chicks nearby increased. Chipper-calls and wing-arch flights are conducted only in the surrounding of the nest, whilst drumming display flights were performed within a radius of up to 250 m.
      Concerning the BMP mapping method guidelines, it is suggested that observations of pairs be omitted, because true pairs are rarely seen and observations of two migrant birds may easily be erroneously ascribed to pairs. Temporally separated observations of chipper-calling snipes and nest-indications can be assigned to different territories if made more than 200 m apart, whilst centres of drumming-flight 'circles' require an exclusion zone of 500 m. For other observations the standard distance of 1000 m can be maintained. These improvements will benefit the information collected with the BMP mapping method, especially in areas with high densities. Common Snipe Gallinago gallinago

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