Capsule A number of tracking studies have shown an area of the North Atlantic, south of the Charlie-Gibbs Fracture Zone, to be an important overwintering location for seabirds. We conducted seabird observations along a trans-Atlantic transect from Ireland to Canada in April 2014 to test the hypothesis that seabird species richness and abundance will peak in the area of the Mid-Atlantic Ridge. At-sea survey results agreed with previous tracking studies, highlighting the importance of the Mid-Atlantic Ridge area for seabirds.