The sand dunes form the largest habitat above high water. The tallest of the dunes occur nearest the beach and are dominated by marram grass. The older dunes in the middle of the island are lower in height but contain a more diverse flora. Two substantial areas of dune habitat are occupied by the Royal Dublin and St. Anne's golf courses.
The dune habitats are the most reliable place to seen common species such as meadow pipits and skylarks. Scrub in the dunes hold a few pairs reed buntings and wrens.
In between the dune ridges are long low-lying depressions known as 'Dune Slacks'. These areas flood (usually less than 0.5m)in winter and in summer the alder and willow scrub provides nesting sites for a number of the islands small resident passerine populations. In spring and autumn these scrubby areas are regular sites for migrant warblers.
In recent years pine trees planted in the golf courses have provided nesting habitat for species such as hooded crow and wood pigeon.
Some of the buildings associated with the golf courses are used by swallows and house martins for nesting.
Several pairs of mallard and shelduck nest amongst the vegetation of the older dunes and the earth embankments in the golf courses.
Birds of North Bull Island - Dublin Bay (2019) All Rights Reserved.