Landings, abundance series, and biological data for a potential range-wide American eel stock assessment

PURPOSE:
To provide a permanent repository of key data series necessary to build a range-wide American eel stock assessment.
            

DESCRIPTION:
This collection presents data associated with the following report:

Cairns, D.K. 2020. Landings, abundance indicators, and biological data for a potential range-wide American eel stock assessment. Canadian Data Report of Fisheries and Aquatic Science. No. 1311: v + 180 pp.

Much of the data collection is from the Atlantic Provinces of Canada, particularly the Southern Gulf of St. Lawrence. The collection also includes data from elsewhere in the American eel's range in Canada, and also the United States and the Caribbean Basin. 

Files in the collection are as follows.

Cairns2020_AnnexA_ReportTables.xlsx: This Excel file (file size 756 kb) contains all 37 tables  in Cairns (2020) exactly as they appear in the report. 

Cairns2020_AnnexB_EelLengthsAgesEfishingRecords.xlsx: This Excel file (file size 3.1 mb) contains 20,047 records of American eel lengths and other biological data from the Canadian Atlantic Provinces, 1983-2017. Records include weights of 8,915 eels and ages of 2,212 eels. Records of 3,224 electrofishing sessions in the Miramichi River, New Brunswick, 1952-2019, and records of 2,590 electrofishing sessions in the Restigouche River, New Brunswick, 1972-2019 are included.

Cairns2020_AnnexC_EelLengthsAgesDataDefinitions.csv: This .csv file (file size 4 kb) gives data definitions in English and French for the table of eel lengths and other biological data that is contained in Cairns2020_AnnexB_EelLengthsAgesEfishingRecords.xlsx and in Cairns2020_AnnexD_EelLengthsAges.csv.

Cairns2020_AnnexD_EelLengthsAges.csv: This file (file size 2.0 mb) presents in .csv format the table of eel lengths and other biological data that is also presented in Cairns2020_AnnexB_EelLengthsAgesEfishingRecords.xlsx.

Cairns2020_AnnexE_EelEFishingDataDefinitions.csv: This .csv file (file size 2 kb) gives data definitions in English and French for the table of eel electrofishing data that is contained in Cairns2020_AnnexB_EelLengthsAgesEfishingRecords.xlsx and in Cairns2020_AnnexD_EelLengthsAges.csv.

Cairns2020_AnnexF_EelEFishing.csv: This file (file size 314 kb) presents in .csv format the table of eel electrofishing data that is also presented in Cairns2020_AnnexB_EelLengthsAgesEfishingRecords.xlsx.

Cairns2020_AnnexG_OtolithImageMetadata.csv: This .csv file (file size 2 kb) provides metadata for the collection of eel otolith images.

Files with names starting with EelOtos . . . . : These .tif, .jpg, and .bmp image files are in zipped format with a summed size of 5.3 gb. The files give magnified photos of 1,838 eel otoliths that have been prepared for age reading. Samples are from the Atlantic Provinces of Canada. Individual otolith codes in Cairns2020_AnnexB_EelLengthsAgesEfishingRecords.xlsx and in Cairns2020_AnnexC_EelLengthsAgesDataDefinitions.csv match the codes embedded in otolith image filenames.
            

PARAMETERS COLLECTED:
American eel landings, number caught, and effort of commercial and research fishing gear. American eel lengths, ages, sex and other biological data and sampling locations.

NOTES ON QUALITY CONTROL:
All keypunched records of landings, densities, and other data were verified against original sources. Landings and abundance indices were reviewed in a Department of Fisheries and Oceans scientific workshop and corrected as necessary. Length and age data were examined by length-weight and length age plots and implausible records were discarded.

PHYSICAL SAMPLE DETAILS:
No physical samples

SAMPLING METHODS:
Landings are from government fisheries agencies.
Abundance indices are from commercial fyke, spear, and trap catch per unit effort, and from research ladder counts and electrofishing records.
Mean elver lengths are compiled from published literature
Sex ratios are compiled from published literature
Locations of biological and genetic sampling are compiled from published literature
American eel lengths are total length of live specimens. Ages are from otolith annulus readings
Electrofishing records are from backpack electrofishing surveys in wadeable waters

USE LIMITATION:
To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.

Organization: Fisheries and Oceans Canada | Pêches et Océans Canada