Trap Count Statistics

These data are compiled by the Department of Marine Resources (DMR) using fishway counts provided by agencies, power companies, and a harvester. "NC" indicates a species is not counted at that location. Fish returns should be considered as provisional.

These fish counting facilities are typically operated from May through early November each year. Staff update the statewide trap catch summary weekly or more often during the peak of the fish migrations. The statewide trap catch table includes counts of sea-run salmon captured on Maine rivers and salmon removed from the river as broodstock for restocking of Maine rivers and DOES NOT include captures of aquaculture strays or captive reared adult salmon released from Federal hatcheries.

Historical annual data for 2012 – 2022 (PDF file, 872 KB)

Recent Trap Counts for Fish Returns to Maine by River
River Trap Location Am.Shad At.Salmon (MSW) At.Salmon (grilse) River Herring Striped Bass Sea Lamprey Trap Opened Trap Closed Updated
Androscoggin Brunswick
13
3
5
67927
0
491
May 12
November 15
November 20, 2023
Aroostook Tinker Dam
NC
0
0
NC
NC
NC
July 4
October 27, 2023
Kennebec Benton Falls
2
3
0
4154124
0
20
May 9
October 31
September 6, 2023
Kennebec Lockwood Dam
4
148
10
136717
91
7
May 8
October 31
November 6, 2023
Narraguagus Cherryfield
300
6
0
NC
0
172
April 20
October 27, 2023
Penobscot Milford fish lift
4154
1705
N/A
5490195
39
1860
April 24
November 15
November 20, 2023
Penobscot Orono
3
13
0
245528
0
1040
April 27
November 15
November 20, 2023
Penobscot Weldon Dam
NC
NC
NC
NC
NC
NC
November 20, 2023
Saco Cataract (East)
1276
1
0
1263
37
1
May 12
July 17
October 29, 2023
Saco Skelton
44
4
0
2202
0
0
May 12
October 29, 2023
St. Croix Milltown Dam
675
0
0
841357
0
0
April 14
August 28, 2023
Union Ellsworth
1
0
0
1373355
0
0
May 1
October 31
November 20, 2023

Atlantic salmon MSW = multi sea winter (≥ 63 cm fork length); grilse = one sea winter (< 63 cm fork length)
River herring counts = combined count of alewife and blueback herring

Data Sources and Details
River Trap Location Sources and Details
Androscoggin Brunswick Counts conducted by DMR and Brookfield Renewable Energy Group.
Aroostook Tinker Dam Counts provided by Algonquin Power.
Kennebec Benton Falls Counts conducted by DMR.
Kennebec Lockwood Dam Counts provided by Brookfield Renewable Energy Group.
Narraguagus Cherryfield Counts provided by MDMR. River herring and small bodied(
Penobscot Milford fish lift Due to trap operations grilse will be added to the MSW counts. Counts provided by MDMR
Penobscot Orono Counts provided by Brookfield Renewable Energy Group.
Penobscot Weldon Dam Counts provided by Brookfield Renewable Energy Group. River herring were documented in the fishway, but no counts are provided.
Saco Cataract (East) Counts provided by Brookfield Renewable Energy Group. No counts are currently made at West Channel
Saco Skelton Counts provided by Brookfield Renewable Energy Group.
St. Croix Milltown Dam Counts provided by St. Croix International Waterway Commission.
Union Ellsworth Counts provided by Brookfield Renewable Energy Group.

Atlantic Salmon Trap Protocols (PDF file, 44 pages)

Atlantic Salmon Aquaculture Escape Protoco (PDF file, 17 pages)