[Footnote 2: This summary is based on information provided at the meeting by Mr. Gregory Streveler.]
The distribution in and use of Glacier Bay by humpback whales was not well known until Charles and Virginia Jurasz began observations in 1973. Prior to this, only personal recollections of Park Service employees of the occurrence of humpback whales in the 1950's and the 1960's exist. In 1967, 60 identifiable humpback whales were observed in three southeast Alaskan areas, i.e., Lynn Canal, Frederick Sound, and Glacier Bay. The number of identifiable whales remained relatively constant until 1974 in Lynn Canal, and 1978 (July 17) in Glacier Bay (Tables 1-3). In the respective areas, the number of identified whales decreased from 15 and 19 to 1 and 3, respectively. Concurrently, the number of identified whales sighted in Frederick Sound increased.
TABLE 1. Relative abundance and distribution of identified humpback whales in southeast Alaskan waters 1967-79[a]
Year 67 68 69 70 71 72 73 74 75 76 77 78 79 -------------------------------------------------------------------
Glacier Bay 20 20 20 20 20 20 25 25 25 25 25 19/3[b] 3 -------------------------------------------------------------------
Lynn Canal 15 15 15 15 15 15 15 1 3 3 3 1/5 5 -------------------------------------------------------------------
Frederick 25 25 25 25 25 25 25 35 40 40 40 40/50 80 Sound -------------------------------------------------------------------
Total 60 60 60 60 60 60 65 61 68 68 68 60/58 88 -------------------------------------------------------------------
[Footnote a: Specific dates of censuses, sighting techniques and sighting effort not given. Based on a table presented by the Juraszs at the meeting.]
[Footnote b: First number signifies number originally counted at beginning of season/second number after decrease in number of whales in Glacier Bay and increase in other areas. The identified whales that left Glacier Bay are not necessarily the same individuals that produced the increased numbers in Lynn Canal and Frederick Sound later.]
TABLE 2. Number of humpback whales (individual census) entering Glacier Bay during "influxes". (modified from Jurasz and Jurasz, 1979)
------------------------------------------------------ Year 1976 1977 1978