|Abstract or Summary
- The evaluation of social investment in water pollution control
has been retarded by a lack of methodology with which to evaluate
the direct benefits. The objective of this dissertation was to develop
theory and methodology for estimating direct recreational benefits
associated with the protection of sport fisheries. An inter-disciplinary
case study of pulp mill waste disposal alternatives at Yaquina Bay,
Oregon, provided the setting for research.
Methodology for estimating direct benefits was based on a bio-economic
model of sports angling. A theory of angler demand behavior
was developed, with special consideration of the "quality" of the
recreational experience. This quality factor was specified as
"angler success per unit of angling effort". The aggregate relationship
between these two variables in a sport fishery was termed a
"success-effort relationship". Conventional demand relationships between quantity, price, and income were also postulated.
A biological production function for a sport fishery was envisioned
between inputs of angler effort and an output, angler yield.
The marginal product was termed a biological "success" function.
Equilibrium levels of success and effort are determined by the
biological "success" and behavioral "success-effort" relationships.
Water pollution would reduce the level of water quality, lower the
biological production function, and reduce the equilibrium levels
of success and effort. The reduced level of effort would be manifested
in a decreased net economic value of the sport fishery.
Direct benefits of water pollution control would be equal to the
averted reduction in net economic value.
Data for empirical estimation of the biological "success",
behavioral "success-effort", and conventional demand functions
were obtained from a field survey of Yaquina Bay sports anglers,
two related mail surveys, and secondary sources. Estimates of
these three types of relationships were made for each of three
major sport fisheries in the estuary.
The "success-effort" relationships were estimated by multiple
regression analysis of time-series and cross-sectional data. The
level of salmon angling effort was significantly responsive to success
changes at fisheries similar to Yaquina Bay. The degree of response
was expressed in terms of a "success elasticity". Two short-run
success elasticity estimates (.375 and .584) were made for offshore
salmon angling at Newport, and a long-run estimate of .999
was made for off-shore salmon angling at Winchester Bay.
Bottomfish anglers at Yaquina Bay were not significantly
responsive to success changes in time-series analyses, although
the results of a mail questionnaire which posed hypothetical "success-effort"
situations indicated that the response would be greater if angler
knowledge of current success could be increased. Cross-sectional
analyses of these data also revealed that increased angler
incomes and distances from the fishery were reflected in larger
Demand equations were estimated for each sport fishery. Net
economic value of the total Yaquina Bay sport fishery was estimated
to be $22,747 per year. A non-discriminating monopolistic owner
of the fisheries could maximize revenues at this level by charging
$1.50 per angler day for salmon and bottomfish angling, and $1.00
per day for clam digging. Negative income elasticities for bottomfish
angling and clam digging prevented the projected yearly rate of
increase in net economic value (2.25 percent) from being larger.
The methodology for estimating direct benefits was illustrated
with a hypothetical water pollution control alternative at Yaquina Bay.
The "success elasticities" were used to reduce each quantity observation
in the demand models, and estimation of the revised demand
equations facilitated a comparison of net economic values with and
without water pollution control. The methodology will be used later
to evaluate direct benefits from each pollution control alternative
at Yaquina Bay.