Positions averaged over 2-day periods for six shearwater pairs, (a) male and (b) female, during the period immediately after the return from winter migration and before the egg is laid (pre-laying exodus). Colours are consistent within pairs. Most male birds remain close to the colony while the females move further away, with four moving towards the shelf edge southwest of Ireland. All females laid an egg immediately after returning to the colony after these trips, except FR88595, which stayed in the Irish Sea—shown in blue. Bathymetry contours at 1000 m intervals indicate the edge of the continental shelf.