Seipt et al : Identification of Balaenoptera physalus in Massachusetts Bay 



275 



I I III 



'l,' 



"is \ S I 15 \ 15 I 15 I 15 15 I 15 



MAR APH MAY JUN JUL AUG SEP OCT 



Figure 3 



Observed temporal occurrence of individual fin whales in Massachu- 

 setts Bay during 1987. Individual whales are ordered (top to bot- 

 tom) by date of first sighting; each row of marks represents the dates 

 on which one individual was seen during the year. A black dot to 

 the left of the vertical a.xis signifies that the individual concerned 

 had been observed in at least one previous year of the study period. 



