Mass mortalities and mass extinction

Are mass mortality and mass extinction related? In an interesting paper, Zi nsmeister (1998) describes a 1-3 m thick sediment layer rich in fish bones just above the K-T boundary on Seymour Island. according to Zinsmeister thi s might 'represent the first documented, direct evidence of a kill event as sociated with the bolide impact 65 m.y. ago'. In this note I will discuss w hy I think it may not.