The Northern gannet suffered the most of any birds from the oil spill last year in the Gulf.
Due to these migration timetables, most of the northern gannets killed in the Gulf last year were likely immature birds. Which means the real impact of their deaths will not show up until those birds would have reached sexual maturity—at about 5 or 6 years of age—or between now and far beyond, since gannets can live at least 21 years. From the paper:
Most adult gannets had returned to Canadian colonies by 20 April 2010, although more than 50,000 immature gannets were in the Gulf at the time and suffered oil-related mortality. Hence, two probable outcomes are (i) a lagged (likely difficult to detect) population decrease or (ii) mortality will be buffered by age-related life-history processes.
