384 
Fishery Bulletin 113(4) 
ing the values of DCP abundance found in the 24,000- 
m 2 areas surveyed within cells to estimate the number 
of DCPs in each square kilometer of open water, we 
computed a mean of 105 DCP/km 2 in open water in the 
6 waterbodies that produced 61-74% of the commercial 
hard-shell crab catch in 2006-2008 in North Carolina 
from Core Sound south to the South Carolina border. 
Extrapolated DCP densities in open water for each wa- 
terbody ranged from 6 DCP/km 2 in the Newport River 
to 301 DCP/km 2 in Topsail Sound (Fig. 3). Two-way 
ANOVA revealed that estimates of DCP densities dif- 
fered significantly by waterbody (F ( 3)=4.18, P=0.007) 
but not by habitat type (Fq)= 0.043, P=0.84), and re- 
vealed no interaction between these factors (F(g)=0.448, 
P= 0.89) (Fig. 3). Likewise, we did not detect differences 
in DCP density (P>0.37) by habitat type when analyzed 
within each waterbody. 
During our sampling of the 201 1-km 2 cells over 23 
survey days from April to November 2010, 1211 AF- 
CPs were observed concurrently with DCPs (Table 1), 
yielding a mean AFCP density of 19 AFCP/km 2 in open 
water. The densities of AFCPs in open water ranged 
from 8 AFCP/km 2 in Cape Fear River to 32 AFCP/ 
km 2 in Bogue Sound (Fig. 3). Using 2-way ANOVA, 
we did not detect differences in the densities of AF- 
CPs by waterbody (F( spO.232, P= 0.87) or by habitat 
type (F(d= 0.627, P= 0.26), and any interaction between 
these factors (F< gpO.66, P=0.73) (Fig. 3). As with the 
DCPs, the density of AFCPs did not differ significantly 
(P>0.29) by habitat type when analyzed within each 
waterbody. 
Of the 201 cells sampled, 23 cells represented 2 dif- 
ferent habitat types (accounting for 46 of 201 samples 
because they were sampled twice) and 155 cells rep- 
resented only 1 habitat type. A 2-way ANOVA of the 
155 cells that represented only 1 habitat type yielded 
results similar to those of the analyses that included 
all 201 cells. For the subset of 155 cells, DCP densi- 
ties differed significantly by waterbody (F ( 3)=3.56, 
P=0.012) but not by habitat type (F ( d=0.18, P- 0.89), 
and there was no interaction between these factors 
(F(8)=1.06, P=0.39). In contrast, for this subset of cells, 
we detected no differences in ACFP densities by water- 
body (F(3)=0.50, P= 0.66) or by habitat type, (F(i)=0.77, 
P=0.38) and no interaction (F( gp0.72, P= 0.67) between 
these factors. Additionally, we detected no differences 
in DCP density or AFCP density among habitat types 
within waterbodies. 
Characterization of derelict crab pots 
Of the 106 DCPs found during field surveys, 92 (86.8%) 
were retrieved. These 92 DCPs were in the water for an 
estimated mean of 2.09 years (SD 1.30). For retrieved 
DCPs, condition was ranked on a scale ranging from 1 
to 10 with a mean value of 6.8 (SD 2.74) (see ranking 
system in Table 2; see Fig. 2 for examples of DCPs in 
poor [rank value of 9] and fair [5] condition). Of these 
pots, 34 DCPs (37%) were functional and capable of 
trapping organisms (Fig. 2), and these DCPs had no 
markings or floats that would make visual detection 
possible from the surface. About 51% or 47 of the 92 
DCPs were buried in estuarine sediments and had a 
mean burial depth of 7.87 cm (SD 10.57) measured 
from pot bottom. With organisms, such as macroalgae, 
soft corals, sponges, tunicates, bivalves, and bryozoans 
growing on their walls, 27 DCPs supported fouling 
communities. 
Bycatch of derelict crab pots 
Of the 92 DCPs retrieved for analysis of bycatch (Ta- 
ble 3), 38 DCPs (41.3%) contained bycatch organisms. 
A total of 45 taxa were identified in or on these pots. 
Of these 45 identified taxa, 18 species (Table 4), repre- 
sented by 531 individuals, were bycatch, inhibited from 
leaving the DCP. The most abundant bycatch species 
of fisheries interest were blue crab and Florida stone 
crab; sheepshead (Archosargus probatocephalus) and 
black sea bass ( Centropristis striata) were also among 
DCP bycatch (Fig. 4). 
Of the 25 blue crab found as bycatch, all were con- 
sidered adults (CW >5.6 cm [point to point], the mini- 
mum size of mature females as defined in NCDMF 9 ; fe- 
males also had to exhibit a rounded abdominal apron), 
10 were dead, and 11 were of legal market size (males 
>12.7 cm CW and females >17 cm CW [NCDMF 9 ]); for 
3 of these 25 crab, size was estimated allometrically 
from claw size. Of the 69 Florida stone crab found as 
bycatch, only 1 was dead and 23 (33%) were juveniles 
(CW: 1.25-3.00 cm; Lindberg and Marshall 10 ). 
Blue crab bycatch abundance did not differ signifi- 
cantly among waterbodies (F ( 2)=1.50, P=0.23) or among 
habitat types (Fq)= 0.06, P=0.80) (Fig. 4). The interac- 
tion between these factors was significant (F(g)= 2.66, 
P=0.02) as a consequence of relatively high numbers 
of blue crab found in estuarine edge habitat in Core 
Sound and in marsh creek habitat in the Cape Fear 
River. The relative proportions of available estuarine 
edge and marsh creek habitats in these respective wa- 
terbodies did not explain patterns in abundances of 
blue crab in DCPs. Bycatch abundance of Florida stone 
crab did not differ significantly among waterbodies 
(F(2)=0.37, P=0.70) or among habitat types (Fq)= 2.74, 
P=0.10) (Fig. 4). The interaction between these fac- 
tors was not significant (F ( 6>=2.16, P=0.056), yet it 
was influenced by the relatively high abundance of 
Florida stone crab found in estuarine edge habitat in 
Core Sound, which was dominated by juveniles, and in 
marsh creek habitat in Bogue Sound. 
The most important bycatch species of conservation 
interest were 5 diamondback terrapin and 1 clapper 
rail ( Rallus crepitans). Other abundant nonfishery spe- 
cies were mud crabs (family Xanthidae), portly spider 
crab ( Libinia emarginata), blennies (suborder Blennioi- 
dei), pinfish (Lagodon rhomboides), and oyster toadfish 
( Opsanus tau ). Eastern oyster ( Crassostrea virginica ) 
had recruited to 16 of the 92 pots retrieved, and re- 
cruitment of northern quahog ( Mercenaria mercenaria) 
was also substantial. Several species of bryozoans (phy- 
