2.3 Black Jack Reef, south Vieques Island, PR
arcía et al. (2004) reported on the existence of a deep hermatypic reef, locally known as
lack Jack, located south of Vieques Island, PR. Black Jack is an outer shelf promontory, or
seamount that lies close to the shelf-edge, at about two nautical miles off from Ensenada
Bay (Figure 2). The seamount rises from a depth of 51 m to a reef top at 30 m. At the
seamount pinnacle, the reef exhibited moderate abundance of soft corals, including many
large colonies. Stony corals were found mostly as encrusting and mound-shaped colonies
interspersed among the reef top without providing much topographic relief. Great Star Coral
(Montastrea cavernosa) was visibly the most abundant coral. Boulder Star Coral M.
s of 36 - 40
eclin sharply n ab
tony oral cov r increases
ubstantially. A digital photo album of Black Jack Reef is presented as Plates 4-9.
04) provided
ntitative assessment of the benthic co
ity at Black
f based on five, 10 m long video-transects within a depth range of 36 – 40 meters
e deeper terrace. A total of 25 species of scleractinian corals, t
g 12 within video-transects. Live
ged 28.8 % ( ge 25
40.4 %) within video-transect a s. Bou
Star C
u
ran
as the dominant coral species in terms of
substrat
9
pre
g 76 % of the total live coral
at dep
between 36 – 40 meters (Table 3). Boulder Star Coral exhibited laminar, or flattened
th
with closely
s
der
ze and low relief. Corals grow
a pedestal of
unknow
la
otective habitat underneath the coral.
aminar
growth p
e
aptation for opt
light ut
that prese
ve
ve
d that were present in at leas
out of
transects
th
star
Coral (
s astreoides), G
’s She
urf algae was the dominant biological assemblage in terms of substrate cover with 57.4 %.
(Halimeda copiosa) were also present
gorgonians presented a mean abundance of 2 colonies per transect in the deep terrace and
G
B
annularis) and Lettuce Coral (Agaricia sp.) were also part of the main stony coral
assemblage at the reef top. The reef slopes down to a deeper terrace at depth
meters where soft corals d
e
i
undance and s
c
e
s
García et al. (20
a qua
mmun
Jack Ree
(120 – 132 feet) on th
wo
antipatharians and one hydrocoral were identified, includin
coral cover avera
ran
.0 –
rea
lder
oral (Montastrea ann laris- f ksi) w
e cover (mean: 21. %), re sentin
cover
ths
grow
spaced colonie of mo ate si
from
n origin, creating a rge pr
The l
attern appears to b an ad
imum
ilization. Other coral species
nted substrate co r abo 1% an
t four
five
surveyed include e Mu
d Hill
Porite
raham
et
Coral (Agaricia grahamae) and Great Star Coral (Montastrea cavernosa). One large colony
of the bushy black coral (Antipathes caribbeana) was present in the deep terrace of Black
Jack Reef.
T
Fleshy (Lobophora variegata) and calcareous algae
within transect areas. The combined cover by benthic algae was 64.2 %. Encrusting
sponges were present in all transect surveyed with a mean cover of 5.8 %. Erect
26
arcía et al. (2004) reported on the existence of a deep hermatypic reef, locally known as
lack Jack, located south of Vieques Island, PR. Black Jack is an outer shelf promontory, or
seamount that lies close to the shelf-edge, at about two nautical miles off from Ensenada
Bay (Figure 2). The seamount rises from a depth of 51 m to a reef top at 30 m. At the
seamount pinnacle, the reef exhibited moderate abundance of soft corals, including many
large colonies. Stony corals were found mostly as encrusting and mound-shaped colonies
interspersed among the reef top without providing much topographic relief. Great Star Coral
(Montastrea cavernosa) was visibly the most abundant coral. Boulder Star Coral M.
s of 36 - 40
eclin sharply n ab
tony oral cov r increases
ubstantially. A digital photo album of Black Jack Reef is presented as Plates 4-9.
04) provided
ntitative assessment of the benthic co
ity at Black
f based on five, 10 m long video-transects within a depth range of 36 – 40 meters
e deeper terrace. A total of 25 species of scleractinian corals, t
g 12 within video-transects. Live
ged 28.8 % ( ge 25
40.4 %) within video-transect a s. Bou
Star C
u
ran
as the dominant coral species in terms of
substrat
9
pre
g 76 % of the total live coral
at dep
between 36 – 40 meters (Table 3). Boulder Star Coral exhibited laminar, or flattened
th
with closely
s
der
ze and low relief. Corals grow
a pedestal of
unknow
la
otective habitat underneath the coral.
aminar
growth p
e
aptation for opt
light ut
that prese
ve
ve
d that were present in at leas
out of
transects
th
star
Coral (
s astreoides), G
’s She
urf algae was the dominant biological assemblage in terms of substrate cover with 57.4 %.
(Halimeda copiosa) were also present
gorgonians presented a mean abundance of 2 colonies per transect in the deep terrace and
G
B
annularis) and Lettuce Coral (Agaricia sp.) were also part of the main stony coral
assemblage at the reef top. The reef slopes down to a deeper terrace at depth
meters where soft corals d
e
i
undance and s
c
e
s
García et al. (20
a qua
mmun
Jack Ree
(120 – 132 feet) on th
wo
antipatharians and one hydrocoral were identified, includin
coral cover avera
ran
.0 –
rea
lder
oral (Montastrea ann laris- f ksi) w
e cover (mean: 21. %), re sentin
cover
ths
grow
spaced colonie of mo ate si
from
n origin, creating a rge pr
The l
attern appears to b an ad
imum
ilization. Other coral species
nted substrate co r abo 1% an
t four
five
surveyed include e Mu
d Hill
Porite
raham
et
Coral (Agaricia grahamae) and Great Star Coral (Montastrea cavernosa). One large colony
of the bushy black coral (Antipathes caribbeana) was present in the deep terrace of Black
Jack Reef.
T
Fleshy (Lobophora variegata) and calcareous algae
within transect areas. The combined cover by benthic algae was 64.2 %. Encrusting
sponges were present in all transect surveyed with a mean cover of 5.8 %. Erect
26