Title 50
SECTION 660.413
660.413 Overfished species rebuilding plans.
§ 660.413 Overfished species rebuilding plans. Link to an amendment published at 86 FR 9302, Feb. 12, 2021.For each overfished salmon stock with an approved rebuilding plan, annual management measures will be established using the standards in this section, specifically the target date for rebuilding the stock to its maximum sustainable yield (MSY) level (generally expressed as SMSY) and the harvest control rule to be used to rebuild the stock.
(a) Klamath River Fall-run Chinook Salmon (KRFC). KRFC was declared overfished in 2018. The target year for rebuilding the KRFC stock is 2020. The harvest control rule during the rebuilding period for the KRFC stock is the de minimis control rule specified in the FMP and at § 660.410(c), which allows for limited fishing impacts when abundance falls below SMSY. The control rule describes maximum allowable exploitation rates at any given level of abundance. The control rule is presented in Figure 1 of subpart H of this part.
(1) The KRFC control rule uses reference points FABC MSST, SMSY, and two levels of de minimis exploitation rates, F = 0.10 and F = 0.25. The maximum allowable exploitation rate, F, in a given year, depends on the pre-fishery ocean abundance in spawner equivalent units, N. At high abundance, the control rule caps the exploitation rate at FABC; at moderate abundance, the control rule specifies an F that results in SMSY spawners; and at low abundance (i.e. when expected escapement is below SMSY), the control rule allows for de minimis exploitation rates with the abundance breakpoints defined as: A = MSST/2; B = (MSST + SMSY)/2; C = SMSY/(1 - 0.25); D = SMSY/(1 - FABC), as shown in Figure 1 of subpart H of this part. For N between 0 and A, F increases linearly from 0 at N = 0, to 0.10 at N = A. For N between A and MSST, F is equal to 0.10. For N between MSST and B, F increases linearly from 0.10 at N = MSST, to 0.25 at N = B. For N between B and C, F is equal to 0.25. For N between C and D, F is the value that results in SMSY spawners. For N greater than D, F is equal to FABC.
(2) [Reserved]
(b) Sacramento River Fall-run Chinook Salmon (SRFC). SRFC was declared overfished in 2018. The target year for rebuilding the SRFC stock is 2021. The harvest control rule during the rebuilding period for the SRFC stock is the de minimis control rule specified in the FMP and at § 660.410(c), which allows for limited fishing impacts when abundance falls below SMSY. The control rule describes maximum allowable exploitation rates at any given level of abundance.
(1) The SRFC control rule uses the reference points FABC, MSST, SMSY, and two levels of de minimis exploitation rates, F = 0.10 and F = 0.25. The maximum allowable exploitation rate, F, in a given year, depends on the pre-fishery ocean abundance in spawner equivalent units, N. At high abundance, the control rule caps the exploitation rate at FABC; at moderate abundance, the control rule specifies an F that results in SMSY spawners; and at low abundance (i.e. when expected escapement is below SMSY), the control rule allows for de minimis exploitation rates with the abundance breakpoints defined as: A = MSST/2; B = (MSST + SMSY)/2; C = SMSY/(1 - 0.25); D = SMSY/(1 - FABC), as shown in Figure 1 of subpart H of this part. For N between 0 and A, F increases linearly from 0 at N = 0, to 0.10 at N = A. For N between A and MSST, F is equal to 0.10. For N between MSST and B, F increases linearly from 0.10 at N = MSST, to 0.25 at N = B. For N between B and C, F is equal to 0.25. For N between C and D, F is the value that results in SMSY spawners. For N greater than D, F is equal to FABC.
(2) [Reserved]
[85 FR
75921, Nov. 27, 2020]