Occurrences of wader species in summer at North Bull Island, Dublin Bay

Tom Cooney

The purpose of this work was to determine the frequency of occurrence of wader species in summer. In addition it was hoped this work would clarify whether there is a clear cut-off point between wintering populations, spring and autumn passage migrations and non-breeding summering birds. Can duration of stay of winter visiting species be determined?

This survey is in many ways a continuance of the detailed work carried out by Holohan (2008). In the current survey, the presence or absence of species was recorded on a weekly basis each year (2012 to 2016) from May to mid-July. In 2017 weekly counts were carried out from May to mid-July to quantify the wader populations.

Results to date indicate that many waders species are either present throughout the summer months or are only absent for short periods. Although the number of birds present in mid-summer are generally low, it is clear that for most species there is not clear cut-off point between departure of wintering populations, passage migration and summering birds. In addition, for most wader species duration of stay cannot be calculated with any degree of certainty.

Birds of North Bull Island - Dublin Bay (2017) All Rights Reserved.