Snowy Grouper Feeding 
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of Cape Lookout to south of Cape Hatteras. Exploratory fishing 
was occasionally conducted over smooth bottom (247-305 m) where 
bait fishes were detected by the fathometer. No snowy grouper and 
only a few scorpionfish were caught. In addition to exploratory 
handline effort, a longline set was made over sand bottom south of 
Cape Lookout on 23 June 1985. Between 1245 and 1410 hours 102 
hooks were fished in 240 m. No fish were caught, and most of the 
bait was untouched. Open bottom sets were discontinued for eco- 
nomic reasons. 
We suspect that adult snowy grouper are sedentary, remaining 
at a specific reef site at least seasonally. During daylight hours 
they forage in the open, often near the top of the reef. They feed 
on small, schooling fish and squid, ambush slower moving deca- 
pods and non-schooling fishes, and occasionally move short dis- 
tances onto sand or mud substrate adjacent to the reef to forage. 
Direct observation to support territorial behavior of individual 
snowy grouper was impossible. Based on our experience with at- 
tempted release efforts of small (<335 mm) snowy grouper, an in- 
ternally injured fish could not survive a 155-m descent to the bottom. 
However, three different observations lead us to hypothesize that 
groupers associate with a home reef on a seasonal basis. First, 
specific locations produced grouper for several consecutive months 
and in some cases over a period of at least 5 years. Second, on at 
least two occasions snowy grouper were caught with rusting circle 
hooks in their mouths. These hooks were the same type and size 
used on our previous trips to the sites when several uncrimped 
hooks were pulled from leaders. These fishing sites were virgin or 
were infrequently fished commercially. Third, a specific plastic teaser 
skirt was torn from the terminal tackle during one trip and recov- 
ered 6 weeks later in a 1.4-kg snowy grouper at the same 146-m 
site. 
Snowy grouper probably move short distances from hard 
bottom to feed over sand or mud substrate. Single shelf-edge or 
upper-slope wrecks and specific reefs in 146-219 m have provided 
harvests of 22,680 kg or greater in a period of less than 3 months 
(L. Davidson, commercial fisherman, personal communication). Small 
areas are not likely to support such biomass even seasonally if the 
fish were restricted to feeding on or above hard bottom, unless 
feeding was restricted because of spawning or other activity. 
A submersible observation of a large snowy grouper 
aggregation was made in late August 1979 slightly inshore of our 
fishing area (Parker and Ross 1986). Observers estimated nearly 
8,000 snowy grouper per ha, 238 blueline tilefish per ha, and 79 
