SALMONID ENHANCEMENT 51 



tion, and to make a significant contribution to public 

 education. The degree of public participation is reflected 

 in the more than 7,000 volunteers who have worked on 

 enhancement projects. Numerous meetings with inter- 

 ested public and fishing groups have been held, including 

 two extensive rounds of- public consultations, and 

 significant expenditures have been made on information 

 and education. The educator's package, "Salmomds in 

 the Classroom," produced by the Salmonid Enhance- 

 ment Program became the first federally sponsored edu- 

 cation package to be accepted by British Columbia's 

 Ministry of Education. 



Other achievements The most easily measured 

 achievements are those relating to fish production capac- 

 ity. But, in addition, much of the research that has been 

 conducted under the auspices of the enhancement pro- 

 gram has been of value to a wide range of other Oepart- 

 mental activities. And the attention focused on the mana- 

 geability of individual stocks and the ways in which they 

 can be harvested more discretely, in addition to aiding in 

 the selection of priorities for enhancement, is widely 

 beneficial in upgrading stock management generally. 



Evaluation of the indirect benefits of the enhancement 

 program is difficult, but I am nevertheless convinced that 

 they are significant. Moreover, to the extent that they 

 have stimulated more searching appraisals of other 

 Departmental responsibilities, especially those relating to 

 habitat and fisheries management, these benefits will be 

 lasting. 



EMERGING QUESTIONS 



The revised expectations for Phase I suggest that its 

 accomplishments in terms of fish production will be very 

 satisfactory in relation to the funds exjjended. Moreover, 

 the economic returns to the investment promise to be 

 rewarding, though somewhat less rewarding than ongi- 

 nally projected. Social objectives and public involvement 

 and education also appear to have been served. But I 

 must emphasize that these are only expectations at this 

 point. 



The bulk of the benefits accruing from SEP 

 activities are directly related to fish produc- 

 tion which, due to the nature of the resource, 

 will be long term and at this time can only be 

 estimated based on expected production and 

 related impacts.' 



The first returns of adult salmon from the earliest proj- 

 ects are only now beginning to appear, and they will have 

 to be observed over a number of years before the success 

 of the projects is known. Even then the returning adults 

 may not accurately reflect the program's true productiv- 

 ity in view of the complications that have begun to 

 emerge. Here I review the most serious of the questions 



raised. Most of these issues cannot be resolved with the 

 information at hand, and consequently, evaluation of the 

 Phase I projects must remain incomplete. 



Questions will always arise as to how much effort 

 should be devoted to research and evaluation in a major 

 undertaking such as the enhancement program. In the 

 case of Phase I, thorough project evaluation is particu- 

 lariy important because the directions to be taken in the 

 future depend critically on its results. Unfortunately, the 

 groundwork for gathering much of the information nec- 

 essary for comprehensive project evaluation (particularly 

 assessments of stock interactions) has not been laid, and 

 project evaluation may, as a result, be both difficult and 

 uncertain. 



Stock interactions Probably the most widespread con- 

 cern is whether artificially enhanced stocks will result in 

 the destruction of natural stocks, frustrating the apparent 

 gains by simply replacing wild stocks with enhanced 

 stocks. Stock interaction problems are not umque to 

 enhancement efforts; they occur also among wild stocks. 

 As explained in Chapter 2, the less productive stocks in a 

 mixed fishery may be depleted before the maximum sus- 

 tainable yield is reached, and this is believed to have 

 happened with numerous small stocks in the commercial 

 fishery. 



The concern with enhancement is that it may aggra- 

 vate and multiply such problems. The large, artificial 

 enhancement projects, especially hatcheries, can be so 

 successful that the stocks are sometimes increased by 

 hundreds of thousands of fish. And the productivity of 

 spawners is so high that only a small fraction of the stock 

 is required for spawning. Problems arise when these 

 enhanced stocks mingle with wild stocks as they are 

 being fished. To oversimplify a complicated biological 

 problem, the fraction of wild stocks that must be left to 

 provide adequate escapement is oflen several times 

 greater than that required for hatcher\' stocks. In such 

 mixed fisheries when all of the fish that the enhanced 

 stocks can support are harvested, the natural stocks are 

 overharvested and thereby depleted. So for natural 

 stocks, the pressure of overfishing (discussed in Chapter 

 2) is aggravated. Additionally, recent studies indicate that 

 competition and predation occurs among salmon species, 

 so that an increase in one species may result in a decrease 

 in another, quite independently of fishing pressure. The 

 federal-provincial Salmonid Enhancement Agreement 

 apparently foresaw threats of this nature: 



. . .enhancement of one stock could result in 

 a detrimental effect on other natural stocks as 

 a result of the increased fishing effort for the 

 enhanced stock.'" 



Program planning attempts to take account of stock 

 interaction in screening candidate projects. Geographic 



