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Adult-to-Adult Ratios: Hanford Reach Fall Chinook Washington Department of Fish and Wildlife Brood years 1996-2005, Preliminary data

Natural and Hatchery-origin replacement rates
(aka. Recruit-to-Spawner or Adult-to-Adult Ratio)

Hanford Reach	Actual Estimate: In-River Harvest Did Occur1		Had In-River Harvest Not Occurred2
Brood Year	Hatchery Origin	Natural Origin	Hatchery Origin	Natural Origin
1996	4.15	0.76	8.01	1.50
1997	1.50	1.03	3.01	2.55
1998	6.26	2.85	10.83	5.38
1999	5.36	4.27	10.31	9.91
2000	1.56	1.20	4.18	3.24
2001	7.77	1.23	17.37	4.35
2002	2.56	0.55	6.19	1.92
2003	1.25	0.28	2.47	1.14
2004	0.88	0.22	2.59	1.12
2005	9.88	0.77	28.62	3.16
Average	4.12	1.32	9.36	3.43

Adult-to-adult ratios were calculated from the number of adult coded wire tags recovered.
Notice: In-River harvest takes some 60% of returning adults, yet replacement (value >= 1) is still achieved.

Footnotes:
¹ Original document heading is "Adult to Adult Ratio" (Harvest not Included)
² Original document heading is "Adult to Adult Ratio" (Includes Ocean & Columbia River Fisheries Harvest)