151 



humpbacks used the bottom in these areas as a barrier to help capture sand 

 lance schools. My hypothesis (Kenney, 1984) was based upon literature 

 descriptions (Reay, 1970) of the densest populations of sand lance (which 

 burrow into the bottom at night, during dormancy periods, and to escape 

 predators) being found on the tops of small banks and the steep edges of 

 larger banks, where currents maintained high oxygen levels in the sediment 

 pore waters. 



P 3-35/1 4/L 5-7: Our report of humpbacks (with rights, fins, and seis) feeding on 

 euphausiids in the canyons was based on indirect evidence only. Observa- 

 tions were from aircraft, with no plankton samples possible. The fact that all 

 four species were feeding together on the same reddish patches near the 

 surface suggested that the prey was krill. 



P 3-36/1 2/L 11: The sand lance explosion occurred in the 1970's, not so "recent 

 years" any more. In fact, it appears that sand lance populations are currently 

 declining. 



P 3-36/1 3/L 8-10: It is not likely that the whale's tongue is the primary mecha- 

 nism for forcing the engulfed water out through the baleen (see Lambertsen, 

 1983). 



P 3-36/1 5: The jaw-scuffing noted by Hain was seen only in 1991, when hump- 

 backs on Stellwagen were rather scarce. Since humpbacks in the Bays fed on 

 sand lance in many previous years without scraping their faces, it is probably 

 not related simply to feeding on sand lance. It is more likely related to some- 

 thing different about 1991. Possibilities include greatly reduced sand lance 

 stocks, so the whales had to go after the last few remaining, or an influx of 

 other sand lance predators (we also saw many large schools of spiny dogfish 

 and probable bluefish during the airship surveys where the jaw-scuffing was 

 noticed) which caused the sand lance to remain buried most of the time. 



P 3-38/1 1/L 1: Implies that only 4-6 year old females breed. Should probably 

 read "beginning at four to six years old." 



P 3-39/1 4/L 7-9 & 14-15: The CETAP estimates, also utilized in Hain et al., are 

 now 1 2 -i- years out of date, and populations can be expected to have in- 

 creased in that period. 



P 3-39/1 4-/L 17: I could find no mention of pre-exploitation fin whale abundance 

 in the CETAP 1979 Executive Summary (the actual publication date was 

 1981), nor in any of the CETAP reports. If it had been, it would surely have 

 been based on previously published information, which should have been cited 



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