(1) a shift in age structure towards larger mature fish; (2) consistent trends in catch 
rates, upward for red drum (24 to 127%) and downward for spotted seatrout (6 to 
54%); and (3) marked reductions in the year-to-year variability of catch rates for 
both species. Preliminary analysis of these observations suggests that changes in 
environmental conditions in park estuaries caused the changes in fishery stocks and 
nature of harvest. 
1958 - 1986 
Rutherford, E. S., J. T. Tilmant, E. B. Thue, and T. W. Schmidt (1989) Fishery harvest and 
population dynamics of gray snapper, Lutjanus griseus, in Florida Bay and adjacent waters. 
Symp. on Florida Bay: A Subtropical Lagoon. Miami, FL. June, 1987. Bull. Mar. Sci, . 
44(1): 1 39-54. 
Catches of gray snapper, an important recreational gamefish species in south Florida, 
have been monitored nearly continuously since 1958 in Everglades National Park; total 
harvest and effort data have been collected since 1973, and lengths have been 
measured since 1974. Catch rates of gray snapper have fluctuated greatly since 1958 
with peaks in 1959, 1964 - 1966, and 1977 - 1979. Most of the total annual harvest 
from 1973 to 1985 was taken by sport fishermen (78%) and guided parties (21%) with 
the remaining 1% taken by commercial hook-and-line fishermen and net fishermen. 
Total annual harvest of gray snapper in Florida Bay and adjacent waters dropped from 
129,000 to 99,500 fish between 1973-1976, increased greatly to 156,000 fish in the 
mid-1970's, but declined again during the 1980's to 59,000 fish. Effort was linearly 
correlated with harvest (r 2 = 0.973, n = 13). The great increase in harvest in the mid- 
1970's was due to a great increase in guide harvest. The decline in effort, harvest, and 
harvest rates for gray snapper since 1979 is believed due to increased effort for other 
species such as spotted seatrout, as well as reduced stock abundance and recruitment. 
Gray snapper recruit to the park fishery at age 1 and are found in the catch to at least 
7 yrs. Three and 4-yr-old fish make up 87% of the catch. Gray snapper are believed to 
migrate offshore out of the Park to spawn since very few ripe adult fish have ever 
been found in the Park. Gray snapper along the Keys and Florida's east coast live to at 
least 21 yrs old. Although fishing mortality on gray snapper in the park is high, 
averaging F = 0.76, and the stock is growth-overfished, population size and 
recruitment are not controlled by fishing effort within the Park. Environmental factors 
and possibly fishing effort on gray snapper in the adjacent Florida Keys may control 
stock size. 
1958 - 1986 
Rutherford, E. S., J. T. Tilmant, E. B. Thue, and T. W. Schmidt (1989) Fishery harvest and 
population dynamics of spotted seatrout, Cynoscion nebulosus, in Florida Bay and adjacent 
waters. Symp. on Florida Bay: A Subtropical Lagoon. Miami, FL. June, 1987. Bull. Mar. 
Sci. . 4 4 (1): 108-25. 
Catch rates of spotted seatrout, one of the four most popular recreational gamefish in 
Everglades National Park, have been monitored nearly continuously since 1958; total 
harvest and effort data and commercial landings have been monitored since 1973, and 
lengths have been measured since 1974. Sport fishermen catch rates of Florida Bay 
spotted seatrout were higher from 1958 to 1967 than from 1973 to 1985 and reached 
a period of record low in 1973 - 1977. Commercial hook-and-line fishermen and sport 
fishermen together accounted for an average 84% of the total annual spotted seatrout 
catch from 1973 to 1979, with guide fishermen and commercial net fishermen 
accounting for an average 13% and 3% of the catch. During 1973 - 1976, total harvest 
declined from 130,000 to 59,000 fish, then increased to 74,000 fish in 1979 because 
of increased commercial harvest, and declined again in 1980 when bag limits of 10 
fish/person/day greatly restricted the commercial fishery and reduced recreational 
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