GERRITSEN GJ (2011) Counts of juvenile Black-tailed Godwits Limosa limosa in The Netherlands in 2006 - 2010: useful for estimating reproductive output?. LIMOSA 84 (1): 15-20.

Since 2006 the Black-tailed Godwit has been listed as 'near threatened'; by the IUCN. The main driver behind the 6% annual population decrease in The Netherlands is insufficient reproduction, mainly caused by too early and extensive mowing of agricultural grasslands, where the bulk of the population breeds. Mowing leads to direct fatalities among chicks, increased predation rates through lack of sheltering vegetation, and severely reduces availability of insect food for chicks.
In 2006-2010, counts were organised in post-breeding staging and roosting sites, to try to estimate the national production of juvenile godwits. In these five years totals counted varied between 570 and 1760 (Table 1). Undoubtedly these totals are underestimates, arisen because we could not find all sites where young godwits gather in summer, and encountered difficulties in finding sufficient volunteer observers in the holiday month of July. All young godwits roosted in freshwater habitats. During daytime they feed mainly on chironomid larvae in shallow (temporary) wetlands (93%). Most (88%) groups found numbered less than 100 juveniles. The significance of grasslands for feeding may be underestimated in this study , because most observers focused on wetlands.
During the counts each year several colour-ringed juveniles were observed. An improved estimate of the total number of young fledged can probably be achieved in the future by assessing the ratio of colour-ringed to non-ringed juveniles. In a few years the annual numbers of young godwits colour-ringed and controlled can be sufficiently enlarged to enable usefully reliable estimates of national reproduction. #### Black-tailed Godwit Limosa limosa

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