The Maryland Fisheries Service conducted a study that evaluated the survival of striped bass caught on conventional hooks and circle hooks in different environmental conditions in the Chesapeake Bay.
Anglers were let loose in their normal manner, attracting striped bass with bait in the water.
"Fifty striped bass was the target number for each day. Striped bass were caught by chumming and anglers were instructed to hook, play and land the fish in a normal manner."
"The fish were placed in tanks on board DNR transport vessels. Oxygen, temperature and salinity measurements from surface, mid-water and bottom depths were taken at each site several times each day. The most optimal conditions for survival (lowest temperature and highest oxygen) found at each site were duplicated in the tank. When 25 fish were captured, they were transported to the net-pens. The striped bass were held for 72 hours and checked daily for mortality."
17% BASS DEEP-HOOKED
The outlook for half of the deep-hooked fish dying in this study was consistent with other research with striped bass in Maryland.
"The deep hooking rate for conventional bait hooks over the course of the entire study was 17.2%"
OVER HALF OF FISH DEEP-HOOKED DIED
"The deep hooking mortality rate for striped bass caught with conventional bait hooks in this study was 53.1%."
"Studies done here in Maryland have consistently shown the deep hooking mortality rate of striped bass caught with conventional bait hooks to be about 50% regardless of temperature or salinity (57.7% in 1995; 41.0% in 1996 and 56.3% in 1997)."
HOOKS PENETRATED HEART AND LIVER
SEVERE INTERNAL HAEMORRHAGE
"Post mortem examinations of deep hooked striped bass caught with conventional bait hooks showed hook points penetrating heart and/or liver in most dead fish, and severe internal hemorrhage in all dead, deep hooked fish, even when major organs had not been penetrated."
FISH DIE QUICKLY
The researchers stated that the death of the fish was caused by the angler’s hooks or from stress.
"Death in these studies is rapid. More than 75% of the fish that die, die in less than 6 hours and 95% die in less than 24 hours. Other catch-and-release studies with striped bass, shad and white perch show the same mortality pattern. This strongly suggests that mortality of these fish reflects hooking injury or angling stress, not confinement because mortality is rapid and usually associated with severe internal damage from hook damage. Mortality from caging stress would be expressed over time as fish languished in confinement. All fish that survive in the net pens are extremely vigorous at release."