Description: The number of mature salmon migrating from the marine environment to freshwater streams is defined as escapement. Escapement data are the enumeration of these migrating fish as they pass upstream, and are a widely used index of spawning salmon abundance. These data are important for fisheries management, since most salmon harvest occurs near the mouths of rivers where salmon spawn during this migration. Escapement data are collected in a variety of ways. Stationary projects utilize observers stationed along freshwater corridors who count salmon as they pass upriver through weirs or past elevated towers. Sonar equipment placed in the river can also give a stationary escapement count. These counts usually represent a sample, and are expanded to represent a 24h period. Escapement data can also be collected using aerial surveys, where observers in an aircraft provide an index to estimate escapement. In general, escapement counts do not represent total abundance, but instead an index of abundance. Surveys are usually timed to coincide with peak spawning activity, generally in the summer, but in the case of Coho salmon in the fall as well. Some data about non-salmon species are also included. This dataset contains compiled annual data from multiple sources. The .Rmd merges all datasets, identifies and flags duplicate records, and performs quality assurance checks by filtering and graphing results.
Bibliographic
Published
2018-02-12 08:00:00
Keywords
salmon
alaska
escapement
Funder
License
Coverage
Temporal
Begin
1921-01-01 08:00:00
End
2017-01-01 08:00:00
Spatial
Attributes
Name
Description
Unit
Stock.ID
Unique stock identifier
Species
species of stock
Stock
Stock name, generally river where stock is found
Ocean.Region
Ocean region
Region
Region of stock
Sub.Region
Sub.Region of stock
Jurisdiction
Management jurisdiction
Lat
Latitude
degree
Lon
Longitude
degree
UseFlag
Indicates if data should be used in analysis
BroodYear
Brood Year
TotalEscapement
Total escapement value
number
R0.1
number of recruits in 0.1 age class
number
R0.2
number of recruits in 0.2 age class
number
R0.3
number of recruits in 0.3 age class
number
R0.4
number of recruits in 0.4 age class
number
R0.5
number of recruits in 0.5 age class
number
R1.1
number of recruits in 1.1 age class
number
R1.2
number of recruits in 1.2 age class
number
R1.3
number of recruits in 1.3 age class
number
R1.4
number of recruits in 1.4 age class
number
R1.5
number of recruits in 1.5 age class
number
R2.1
number of recruits in 2.1 age class
number
R2.2
number of recruits in 2.2 age class
number
R2.3
number of recruits in 2.3 age class
number
R2.4
number of recruits in 2.4 age class
number
R3.1
number of recruits in 3.1 age class
number
R3.2
number of recruits in 3.2 age class
number
R3.3
number of recruits in 3.3 age class
number
R3.4
number of recruits in 3.4 age class
number
R4.1
number of recruits in 4.1 age class
number
R4.2
number of recruits in 4.2 age class
number
R4.3
number of recruits in 4.3 age class
number
TotalRecruits
number of total recruits
number
Source.ID
Source.ID as seen in stock info table
Source
Source description
Date.data.obtained
Date data was obtained; if original data did not specify the day, the day is recorded as 01
Date.data.incorporated
Date data was incorporated into database; if original data did not specify the day, the day is recorded as 01
