long duration during the peaks of spawning runs is not 

 comparable with an estimate made during normal 

 water levels. 



Streams in which intertidal spawning pre- 

 dominates may present difficult observation conditions 

 at high tide. Spawning salmon in the intertidal zone 

 behave differently when the spawning areas are flooded 

 by the high tide. 



Aerial observations vary with the different 

 types of aircraft used. Observations made from small 

 light planes capable of following winding stream 

 courses are more reliable than those made from larger 

 planes which must fly at considerable height above the 

 stream and generally at greater speeds. 



Physical Observations 



Observations of the characteristics of each 

 stream by different observers have been recorded with 

 varying degrees of accuracy. Many details of stream 

 descriptions are dependent upon the individual observer's 

 ability and knowledge. 



Many stream dimensions are merely estimates. 

 Instruments for measurements were usually not available 

 to observers, and pacing and estimating were used. 



Most basic stream distances have been taken 

 from aerial photographs and are relatively accurate. 

 However, some errors may have occurred where refer- 

 ence points were difficult to identify. Drainage 

 estimates were based on compensating polar planimeter 

 measurements of valley areas, but occasionally drain- 

 age divides were difficult to distinguish and the areas 

 given are only approximate. 



EXPLANATION OF CATALOG FORMAT 



Further descriptions of the data such as estimates 

 of timing, temperature ranges, spawning facilities, 

 etc. , are included under these specific headings in the 

 explanation of the catalog format that follows: 



Stream Designations 



Statistical area number. --The number used by 

 the Alaska Department of Fish and Game to designate the 

 statistical area is given in the upper left side of the 

 heading. 



Stream name. — This appears in the center 

 of the first line of the heading. Recorded names or 

 common local names are used when available. Other- 

 wise unnamed streams of importance are given descrip- 

 tive names corresponding to location or other dis- 

 tinguishing features. Some streams have identical 

 names; they are retained without change due to local 



usage. Many minor streams have no names; hence 

 they are identified only by number. 



Stream number. --This number appears on 

 the right side of the first line of the heading. The 

 letter preceding the number designates the adminis- 

 trative district in Southeastern Alaska: e. g. , "K" 

 for Ketchikan. Continuity of stream numbers along 

 a shoreline is followed where practical. Due to the 

 numerous islands, breaks in the sequence have been 

 necessary. Nonhyphenated numbers designate 

 major or important streams. A catalog number 

 which includes a hyphenated number designates a 

 tributary to the stream of the same number. A cata- 

 log number combining numbers and letters desig- 

 nates a minor stream, either adjacent to or between 

 major streams numbered in sequence. For example, 

 stream number 17A is a minor stream adjacent to 

 major stream number 17. 



Latitude and longitude . --This appears on 

 the second line, left side, of the heading. Location 

 of streams is given by the use of "N" for north lat- 

 itude, and "W" for west longitude, stated in degrees 

 (°), minutes and tenths of minutes ('). Location 

 of the high tide point on the stream is given for 

 positive identification. 



Previous number . --This appears on the 

 second line, right side, of the heading. Stream 

 number or numbers used in the past by Fish and Wild- 

 life Service are given for positive identification of 

 old stream records. 



Geographic location. --This appears on 

 the third line of the heading. Each stream location 

 is described by the administrative district, major 

 channel, bay or inlet, arm or cove, and location 

 within the smallest division given by direction 

 (from true north) and distance (nautical miles). 



Major species. --Included are those species 

 of salmon which furnish the bulk of spawning in 

 the stream. Where more than one dominates, both 

 (or more) are included. 



Other species. --This indicates other known 

 species of salmon and trout using the stream. 



Escapement timing. --The timing is based 

 on systematic stream survey records, which include 

 a number of years of surveys with visits before, near, 

 and after the peaks of abundance. Extensive stream 

 temperature studies were conducted in conjunction 

 with most of these surveys. The earliest runs of 

 salmon occur along the colder mainland streams. 

 The latest runs are in the outer channel and coastal 

 areas where stream levels are dependent upon rainfall. 

 An intermediate timing of the runs occurs in the 



