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Fishery Bulletin 113(4) 
observed AFCPs than of observed DCPs, 1211 versus 
106 (Table 1) and from the 41 times greater survey 
area over which AFCPs were counted, 1 km 2 versus 
24,000 m 2 (or 0.024 km 2 ). 
The results of our limited study of the re-introduc- 
tion of DCPs into specific areas from which all had 
been removed indicate that pots were relocated from 
the areas of their original deployment and loss. In 
all 4 of the cells where annual recruitment was as- 
sessed, DCPs were found with a degree of fouling or 
with sizes of encrusting eastern oysters that implied 
submergence >1 year (5 out of 6 DCPs), although all 
crab pots were removed from these areas 1 year be- 
fore, indicating that relocation rather than deployment 
within the last year was responsible for their presence 
in the cleared plots. We cannot conclude that natural 
physical processes necessarily caused these relocations 
of DCPs because human intervention, such as trans- 
port and discard by trawlers, could also explain the 
movement of these DCPs. In contrast to this evidence 
of DCP mobility, 51% of the 6 DCPs retrieved showed 
evidence of at least partial burial by estuarine sedi- 
ments, a situation that would limit their subsequent 
movement. 
Regulations of a NCDMF crab pot clean-out pro- 
gram that began in 2003 require commercial crabbers 
to remove all pots from the water for a period of 2-3 
weeks, and a crab potting moratorium occurs typically 
from late January to early February. During this time, 
NCDMF crews remove DCPs that they find in North 
Carolina waters. This program is quite limited in scope 
and targets popular crabbing areas. Derelict crab pots 
retrieved by NCDMF are either disposed of, if no iden- 
tification is present, or returned to the owner with a 
fine, if the mandated identification tag remained at- 
tached to the pot. From 2003 through 2011, NCDMF 
removed 21,338 DCPs from coastal waters in North 
Carolina (NCDMF 12 ). 
In one heavily fished waterbody, few DCPs were 
found, possibly because fishermen were regularly re- 
moving derelict gear. Only 4 DCPs were found in the 
9 cells surveyed in Jarrett Bay, within Core Sound, 
which has historically experienced substantial fishing 
and crabbing effort (Avissar, 2006; Cahoon and Hart 13 ; 
Hooper 14 ; and Purifoy 15 ). Part of this bay was open to 
12 NCDMF. 2011. Unpub. data. Marine Patrol, Div. Mar. 
Fish., North Carolina Dep. Environ. Nat. Resour., Morehead 
City, NC 28557 [Records obtained 27 Jan 2011.] 
13 Cahoon, R., and K. Hart. 2004. Evaluating the efficiency 
and necessity of requiring bycatch reduction devices on pots 
in the peeler crab fishery: qualifying and characterizing spa- 
tial and temporal overlap of activities between diamondback 
terrapins ( Malaclemys terrapin ) and the commercial fishery 
for peeler blue crabs (Callinectes sapidus), 13 p. North 
Carolina Sea Grant Project no. 03-FEG-18. [Available from 
North Carolina Sea Grant, 303 College Circle, Morehead 
City, NC 28557.] 
14 Hooper, M. 2010. Personal commun. Hooper Family Sea- 
food, Smyrna, NC 28579. 
15 Purifoy, J. 2010. Personal commun. Inst. Mar. Sci., Univ. 
North Carolina Chapel Hill, Morehead City, NC 28557. 
a trawl fishery in 2010, and traditional crab potting 
areas bordered the trawl areas. Perhaps peer pressure 
from other fishermen or inadvertent collection and re- 
moval by trawlers was responsible for the unexpected 
low number of DCPs in Jarrett Bay. 
Bycatch or residents? 
What motivates organisms to occupy DCPs? Of the re- 
trieved DCPs, 41% contained bycatch, most of which 
was alive. A separate but relevant study (senior author, 
unpubl. data) in Bogue Sound, North Carolina, found 
that scavengers quickly take remains of organisms that 
die in crab pots. Dead bycatch is either consumed or 
becomes so fragmented that it is washed out of the pot 
through the mesh. Only chitinous components and large 
bones remain for >4 days; therefore, deaths attributable 
to DCPs are generally underestimated when using only 
the counts of bycatch found in recovered pots. 
Living blue crab and Florida stone crab were found 
as DCP bycatch in every waterbody and every habitat 
type (Florida stone crab found in the cell in Newport 
River that was sampled for our DCP recruitment study 
were not part of the quantitative survey and therefore 
not included in the bycatch data set). Of the crabs 
found in DCPs, 44% of blue crab and 67% of Florida 
stone crab were of marketable size. 
The range of the Florida stone crab has expanded 
northward into the region of our study. Warming sur- 
face water temperatures in North Carolina estuaries, 
such as the 1.4°C increase in the daily mean surface 
temperatures in Bogue Sound from 1985 to 2005 (Mi- 
cheli et ah, 2008), have probably facilitated the pole- 
ward expansion of populations of Florida stone crab. 
Populations of Florida stone crab have become well es- 
tablished as far north as Pamlico Sound (just north of 
our study area), where salinities are higher than 15, at 
population densities similar to densities observed for 
the Florida Panhandle (Rindone and Eggleston, 2011). 
Habitat changes may have also contributed to the in- 
crease in Florida stone crab abundance in our study 
area. We found more Florida stone crab in estuarine 
edge habitats compared with the abundance observed 
in marsh creek or adjacent ICW habitats (Fig. 4), a pat- 
tern that may be related to the presence of abundant 
rock revetments along shorelines that abut estuarine 
edges. Hard rock and crevice substrate is a favorable 
habitat for Florida stone crab and growing use of rocks 
to stabilize estuarine shorelines may have increased 
abundance of Florida stone crab in such areas (Wong 
et ah, 2010). The degree to which Florida stone crab 
use DCPs and, perhaps, other structural marine debris 
as refuge habitat is unclear. 
Some blue crab and Florida stone crab may escape 
from DCPs; however, as long as they are trapped they 
are not available to the fishery. Nonetheless, increases 
in abundance of Florida stone crab indicate a poten- 
tial for commercial and recreational fisheries of Florida 
stone crab in North Carolina. Although not historically 
developed as a commercial fishery in North Carolina, 
