1998 



OUR LIVING OCEANS 



tion (NASCO), and the International Commis- 

 sion tor the Conservation of Atlantic Ilmas) as 

 well as national governments, including the United 

 States. They will also be the focus of the remain- 

 der of this article. 



LIMIT ANDTARGET 

 REFERENCE POINTS 



Limit and target reference points are signposts, 

 usually expressed in terms of fishing mortality rates 

 or stock biomass, that provide benchmarks with 

 which to compare the state ot the stock and status 

 ol exploitation and which can be used to guide 

 fisheries management. Limit reference points set 

 botuidaries that are designed to constrain exploi- 

 tation within safe biological limits so that stocks 

 retain the ability to produce maximum sustain- 

 able yield. Target reference points identify desired 

 outcomes for the fishery and are therefore intended 

 to meet management goals and objectives. 1 he 

 basic idea of using reference points in a Precau- 

 tionary Approach to fisheries management is that 

 targets should be set sufficiently below limits so 

 that the limits will be avoided with high probabil- 

 ity and targets will be attained on average. 



Ihc L'nited States had already made substan- 

 tial progress in addressing overfishing prior to the 

 development of the Precautionary Approach. In 

 1989, NMFS published guidelines (§50 CFR Part 

 602, Guidelines for the preparation of fishery 

 management plans under the MFCMA) (com- 

 monly referred to as the 602 Guidelines) inter- 

 preting National Standard 1 ofthe MFCN4A with 

 respect to overfishing. The 602 Guidelines pro- 

 vided a formal definition of overfishing: 



"OVFRFISHINI, IS A LEVEL OR RAIF OL LISIIINi; 

 MORTALITY THAT JEOPARDIZES THE LONG-IERM 

 c;AI'AC1TY OF a stock OR STOCK COMPLEX TO 

 PROLW( F [maximum SUSTAINABLE YIELD] ON A 

 CONIlNLIIN(. BASIS." 



I he 602 tjuidelines required that all tisher\' 

 management plans (FMP's) be amended to include 

 measurable definitions of overfishing for each stock 

 or stock complex covered by that FMP. In most 

 FMPs, this directive was interpreted as a recjuire- 

 ment for defining recruitment overfishiii" which 



was generally specified in terms of a limit fishing 

 mortality. A review by Rosenberg et al. (1994) of 

 more than 100 such definitions concluded thai 

 most definitions were biologically sensible and at 

 least neutrally conservative in protecting against 

 recruitment overfishing, although there was room 

 tor improvement especially in terms of the link- 

 age to management actions. 1 he most common 

 definitions of recruitment overfishing were fish- 

 ing mortality rates associated with either 20% or 

 30% of the maximum spawning biomass per re- 

 cruit (i.e. F,||,-,^ and F,,,,,^, see Appendix 4). 



Once overfishing definitions were de\'elopcd 

 and accepted, fishery management councils were 

 required to develop and implement rebuilding 

 plans for overfished stocks. Many of these plans 

 were well underway, and some stocks had even 

 been proclaimed "rebuilt" when the Act 

 (MSFCMA) was reauthorized in 1996 (Sustain- 

 able Fisheries Act, Public Law 104-297). The 

 MSFCMA introduced several new requirements 

 for specifying objective and measurable criteria for 

 determining overfishing and also introduced new 

 or revised definitions for a number of terms re- 

 lated to limits and targets. Most notably, the 

 MSFCMA redefined optimum yield to be no 

 greater than maximum sustainable yield (Fable 1 ). 



I he new definition of optimum yield also included 

 the protection of marine ecosystems as a national 

 benefit to be considered in setting targets. In ad- 

 dition, the MSFCMA incorporated the definition 

 of overfishing first presented in the 1989 Guide- 

 lines, and mandated that specific remedial actions 

 be taken to prevent overfishing and rebuild over- 

 fished stocks. 



The treatment of MSY as a management con- 

 straint in the MSFCMA is consistent with Annex 



II of the L'.N. Straddling Stocks Agreement (UN, 

 1995) which states: 



"Till I ISHINl, MORTALITY RAFF WHICH GFNFRAIFS 

 MAXIMUM SUSIAINABLE YIELD SHOLU D BE RF- 

 CARDFD AS A MINIMUM STANDARD LOR 1 IMIT 

 REFERENCE POINTS." 



In Ma\' 1998, NMFS published new National 

 Standard Ciuidelines (Federal Register, Vol. 63, No. 

 840, p. 24212-24327, Mav 1, 1998) that inter- 

 pret the amended Act (Fable 1 and ihc i.letinition 



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