UW-FRI Daily Update

July 18, 2018 (data through July 17)

Bristol Bay Cumulative Compare

District Cumulative Compare

Figure A. Cumulative C+E Comparison: Comparison of daily cumulative C+E observed for Bristol Bay in 2018, and expected daily values (blue curve). Expected daily values are calculated relative to the 2018 preseason forecast and the average distribution of inshore arrivals (1980–2017). Connected gray dots show the 2018 observed daily cumulative C+E. Green dashed line represents expectations if the run is 2 days early, red dashed line if the run is 2 days late.

Daily Comparisons

Figure B. Daily Catch and Escapement: Observed catch and escapement for years 2014–2017 as stacked bars, compared with 2018 (top). Escapements are in light gray and catches in dark gray. Total run for Bristol Bay is shown in millions of sockeye on the right hand axis.

Port Moller Backcast sigmaTravel1

Figure C. Comparison of Expected & Observed Daily Port Moller Index: 2018 observed and interpolated (gray and black bars) UW-FRI Port Moller Index is compared with expected daily index values (red line and shaded area) for a Bristol Bay run equal to the preseason forecast with average run timing, and exhibiting average Port Moller to inshore travel time (TT) and run-per-index (RPI). Expected daily index values for a run at the preseason forecast, with TT and RPI equal to those observed in 2014-2017 are plotted with blue lines and symbols.

Note: 2014 exhibited shorter TT and higher RPI compared with the 1990-2017 average (and other example years) hence the expected daily indices for the current year being lower and later.

Days in Excess NEW

Figure D. Expected C+E Days: Total number of days in which the catch + escapement exceeded 1.0, 2.0 or 3.0 million fish as a function of the total run size from 1965 to 2017. Fitted lines indicate the expected number of days in excess, for a specific total return. Shaded area encompasses the data for total returns between 44 and 51 million fish. Red outlined diamonds are 2018 observed C+E days in excess of 1.0, 2.0, or 3.0 million fish. Note: the red outlined diamonds will be stacked on the horizontal axis until the first 1.0 million fish day is recorded.

GOA Esc Comparison

Figure E. GOA Sockeye Escapement: 2012-2018 cumulative sockeye escapements to select Gulf of Alaska river systems.

Acknowledgements

Catch and escapement data are collected by the Alaska Department of Fish and Game, and the Bristol Bay Science and Research Institute operates Port Moller test fishery. Data interpretation is conducted by UW-FRI, please direct any questions to Curry Cunningham or Chris Boatright at 907-842-5380.