Marty M. Hale

A 3-year study was initiated in 1992 to characterize the St. Johns River freshwater commercial striped mullet (Mugil cephalus) gill net fishery and estimate bycatch. Each year in fresh water, an estimated 137 fishers using 84 boats fished 1,554 days and harvested 233,109 kg of striped mullet. Approximately 86% of the fishers used the strike technique exclusively, while 14% used both strike and set-net techniques. Striped mullet comprised 99% of the total catch by number. The average annual freshwater game fish bycatch ranged from 86 to 274 fish (< 1 % by number). The extremely low...

An intensive hoop net study was conducted on the St. Johns River, Florida, to: (1) estimate commercial hoop net effort, bycatch and initial gamefish mortality; (2) determine delayed mortality of game fish caught in hoop nets; and (3) estimate riverwide gamefish mortality in hoop nets. A survey of all known hoop net fishers revealed 38 fished 2,386 hoop nets for 794,300 net-days of effort in 1993. Between July 1992 and June 1993, 1,053 commercially-fished hoop nets were observed that were fished 7,320 net-days. Catfish (Ictaluridae) comprised 95% of the 87,278 individuals captured, while...

A 3-year tagging study was conducted to determine movement and distribution of catfish in the St. Johns River, Florida. A total of 8,800 white catfish (lctalurus catus), channel catfish (I. punctatus), brown bullhead (I. nebulosus) and yellow bullhead (I. natalis) were tagged with Floy FD-68B anchor tags from May 1983 through December 1985. Of these tagged fish, 1,227 (13.9%) were recaptured. The highest return was from lake habitat (22.8%) followed by riverine (17.1 %) and tributary (7.0%) habitats. The longest distance travelled was 178.2 kIn upstream. Approximately 52.0% of the...

A low voltage electrofishing device, commonly called a “monkey rig” in Florida, was used to collect catfish for a tagging study on the St. Johns River, Florida. In 40 fishing trips, 3,234 catfish were captured using the “monkey rig”. This inexpensive device was selective for catfish species only. The 16-V to 18-V alternating current agitated the catfish to the surface but fish never exhibited a complete state of tetanus. When electrofishing in waters with surface temperatures warmer than 24˚ C and around underwater structure, the “monkey rig” was an effective collecting device for catfish...

The retention of Floy FD-68B anchor tags and survival of 200 tagged and fin-clipped white catfish (Ictalurus catus) and channel catfish (Ictalurus punctatus) were determined over a 184-day period in 2 0.20-ha ponds. In 1 pond, 50 tagged fish and 50 fin-clipped fish were stocked. In the second pond, 50 tagged and fin-clipped fish and 50 fin-clipped fish were stocked. Of the 70 tagged fish recovered (all tagged fish received 2 tags), all had retained at least 1 tag. Four Floy tags were lost, yielding an overall tag retention of 97.1 %. No separation of plastic sleeves was observed from the...

From December 1981 through March 1983, 71 observations of pound nets were conducted. In 407 net days, commercially important species comprised 93.5% of the total pound net catch while game fish species comprised 4.4%. An average of 1.8 game fish were caught per net day. Harvestable-size game fish (that size retained by sport fishermen) represented 3.6% of the total catch and comprised 81.5% of all sizes of game fish caught. Initial mortality was 3.3% for game fish or 0.06 game fish deaths/ net day. An estimated 68 game fish/km of shoreline/year were caught by the entire pound net fishery...

Incidental game fish capture and mortality in St. Johns River hoop nets is a major source of controversy between sport and commerical interests. The controversy is most severe in that portion of the river from Lake George southward. Project personnel observed 574 hoop nets that had been fished 3,896 hoop net-days over a 12-month period. Four species of catfish comprised 84.8% of the total harvest while the game fish by-catch represented approximately 13%. Harvestable size game fish (that size game fish retained by the sport fisherman) comprised 1.4% of the total harvest. Initial mortality...

The water level of West Point Reservoir is lowered 3 m from October to May for flood control purposes, exposing about 2,900 ha oflittoral zone. The effects of water level fluctuations on the benthic organisms inhabiting this zone were determined from samples taken at 2 bottom contours; the contour exposed during winter drawdown and the contour just below the winter drawdown that remained permanently inundated. During May and July, fewer organisms (P < 0.05) were collected from the contour exposed during drawdown than from the contour never exposed. By August there were no differences (P...