catch. Total annual effort was closely correlated with harvest (r 2 = 0.950). Since 
1980, total annual harvest has increased to early 1970 levels with increases in both 
recreational and guide fishermen harvest. Catch rates and length frequency 
distributions suggest different unit stocks of spotted seatrout in the Florida Bay area 
and the Gulf Coast area of the park. The reduction in spotted seatrout harvest in the 
Florida Bay area appeared due to reduction in fishing effort and to environmental 
factors. Current harvest levels (avg. 100,000 fish yr 1 ) have moderate impact on the 
stock. Average fishing mortality rate for 1973 - 1984 was 0.36 and ranged from 0.20 
to 0.55. Between 13 and 28% of the total recruited stock in the Florida Bay area were 
harvested annually from 1973 to 1984. Age of harvested spotted seatrout ranged from 
age 1 - 8, with ages 3 - 5 providing up to 70% of the catch. Estimated population size 
of spotted seatrout in the Florida Bay area ranged from 686,000 to 786,000 fish from 
1974 to 1978 and then decreased slowly to 631,800 fish by 1984. Recruitment of 
age-1 fish varied from 166,700 to 317,000 fish, peaking in 1976, 1977, and 1984 
and being lowest in 1983. Catch rates were poorly correlated with rainfall and water 
levels in upland marshes. There was no relationship between estimated parent stock and 
recruitment or rainfall/upland water levels and recruitment. 
1958 - 1986 
Tilmant, J. T., E. S. Rutherford, and E. B. Thue (1989) Fishery harvest and population 
dynamics of the common snook (Centropomus undecimalis). Symp. on Florida Bay: A 
Subtropical Lagoon. Miami, FL. June, 1987. Bull. Mar. Sci. . 44(1):523-4. 
(ABSTRACT ONLY.] The Everglades National Park fishery harvest monitoring program 
has provided a record of the recreational snook fishery catch and effort from 1958 to 
present. Length data are available on harvested fish since 1974. Although snook has 
comprised less than 1% of the total recreational fishing harvest they have been 
specifically sought by as many as 15% of the total fishing boats during a given year. 
This species has comprised 1.1% of the total annual reported guide fishermen catch 
since 1984. A marked decline was noted in the annual number of boats successfully 
catching snook from 1974 through 1982. These declines were due to a decline in the 
percent of boats successful for this species as well as a decline in total fishing boats 
within the park. Since 1982, there has been an annual increase in the percentage and 
total number of boats reporting catches and observed harvesting snook. This increase 
has occurred despite closed seasons being placed on the fishery during January- 
February and June - July (June - August 1985 and 1986). The average catch per 
successful boat reached a peak 5.5 fish in 1964 (0.36 fish man* 1 hr* 1 fished) but 
declined to only 2.5 fish (0.20 fish man* 1 hr* 1 ) by 1966. Average reported catch rates 
continued to decline during the 1970's, reaching only 1.3 fish per successful boat (0.12 
fish man* 1 hr* 1 ) in 1979. The average reported catch of snook per successful boat 
remained extremely low through 1982, but then increased in 1983 and 1984. This 
increase in catch rate was not accompanied by an equal increase in harvest per boat 
indicating that large numbers of small snook were being released during 1983 and 
1984. The size distributions of fish harvested during 1983-1984 also suggest a 
recruitment of large numbers of young fish occurred those years. An annual increase in 
the total number of fishermen catching snook since 1983, as well as the increase in the 
catch rate, led to over a two-fold increase in annual harvest from 1982 to 1986. This 
increase in annual harvest has occurred despite restricted size limits, a decreased bag 
limit, and a seasonal closure on the fishery. Since 1974, the average length of snook 
harvested from Everglades National Park has been approximately 635 mm FL (age 4.5 
yrs). Thirty-one percent of the fish observed were less than the 24-in TL (610 mm) 
minimum size placed on the fishery in 1985. Significant differences in annual mean size 
were noted only during 1975 and again in 1982 when average size increased to 711 mm 
FL (28 in). Both 1975 and 1982 may reflect low recruitment year classes. This is 
147 
