This study aimed to identify juvenile queen conch nurseries in South Eleuthera, Bahamas by conducting transects to locate and measure juvenile conch. The researchers hypothesized that juvenile conch would be found mostly in seagrass and sand habitats. They walked transects measuring habitat variables and recording any conch found, noting location, size, and habitat. Identifying nursery habitats is important for protecting this economically and ecologically significant species, as past studies have shown declining populations due to overfishing and lack of enforcement of fishing regulations.

1. Identifying Juvenile Queen Conch Nurseries in
South Eleuthera, The Bahamas
Noelle
Anderson,
Taylor
Fasolo
,
Charlo2e
de
Vaulx,
Julia
Baker,
Greta
O’Marah,
Tim
Sommerfield
Introduction
Purpose: To
determine
locaCons
of
juvenile
queen
conch
aggregaCons
in
order
to
idenCfy
essenCal
nursery
grounds.
Hypothesis: AggregaCons
of
juvenile
queen
conch
in
South
Eleuthera
will
mostly
be
found
in
habitats
of
seagrass
and
sand.
Fig
2
-­‐
Juvenile
queen
conch
shell,
lip
absent.
Siphonal
lenth
(SL)
indicated
by
red
line
Fig
3
-­‐
Adult
queen
conch
shell,
with
flared
lip
• Formed
a
line
perpendicular
to
the
shore,
and
collected
habitat
variables
• Walked
in
a
straight
line,
holding
onto
a
rope,
3
m
apart,
and
looked
for
conch
(Fig.
5)
Transects
were
18
meters
wide
and
length
differed
by
site
• Recorded
all
discarded
shells
or
change
in
bo2om
type
• When
a
conch
was
located,
LocaCon
marked
on
GPS,
and
siphonal
length
and
lip
thickness
(if
present)
measured
(Fig.
2
&
6)
• At
the
end
of
transect
final
habitat
variables
measured
Methods – juvenile transects
Clark,
S.,
Danylchuk,
A.,
Freeman,
B.
2005.
The
Harvest
of
Juvenile
Queen
Conch
(Strombus
gigas)
off
Cape
Eleuthera,
Bahamas:
ImplicaCons
for
the
EffecCveness
of
a
Marine
Reserve.
Gulf
and
Caribbean
Fisheries
InsCtute
56:
705-­‐713.
Danylchuk,
A.
2005.
Fisheries
Management
in
South
Eleuthera,
Bahamas:
Can
a
Marine
Reserve
Help
Save
the
‘Holy
Trinity’?.
Gulf
and
Caribbean
Fisheries
InsCtute
56:
169-­‐177.
Stoner,
A.
2003.
What
consCtutes
essenCal
nursery
habitat
for
a
marine
species?
A
case
study
of
habitat
form
and
funcCon
for
queen
conch.
Marine
Ecology
Progress
Series
257:
275-­‐289.
Stoner,
A.,
Lally,
J.
1994.
High-­‐density
aggregaCon
in
queen
conch
Strombus
gigas:
formaCon,
pa2erns,
and
ecological
significance.
Marine
Ecology
Progress
Series
106:
73-­‐84.
Ray,
M.,
Stoner,
A.
1996.
Queen
Conch,
Strombus
Gigas,
in
fished
and
unfished
locaCons
of
The
Bahamas:
effects
of
a
marine
fishery
reserve
on
adults,
juveniles,
and
larval
producCon.
Fishery
BulleCn
94:
551-­‐565.
Stoner,
A.,
Davis,
M.,
Booker,
C.
2012.
Abundance
and
populaCon
structure
of
queen
conch
inside
and
outside
a
marine
protected
area:
repeat
surveys
show
significant
declines.
Marine
Ecology
Progress
Series
460:
101-­‐114.
Citations
Fig
1
-­‐
A
juvenile
conch
found
at
Wemyss
Bight
Beach
Fig
4
-­‐
An
example
of
a
conch
midden,
boathouse
cut
Queen
conch
(Strombus
gigas)
are
found
throughout
the
Caribbean
in
warm
temperatures
(18-­‐26
oC)
and
shallow
waters,
with
juveniles
found
in
depths
of
1-­‐4
meters;
juveniles
ojen
aggregate
in
high
densiCes
referred
to
as
nurseries
(Stoner
and
Lally,
1994).
Juveniles
(Fig.
1
&
2)
do
not
have
a
thick,
flared
lip
while
adults
do
(Fig.
3).
Their
preferred
habitats
generally
consist
of
sand,
macroalgae,
and
seagrass
(Stoner,
2003).
Queen
conch
is
economically
important
to
The
Bahamas
because
it
is
the
second
largest
fishery
and
a
major
export
(Clark
et
al.
2005).
Ecologically,
queen
conch
are
integral
to
maintaining
healthy
ecosystems
because
as
grazers
they
keep
seagrass
healthy.
Seagrass
serves
as
a
nursery
ground,
a
sand
stabilizer
and
it
is
key
to
nutrient
transport
(Stoner,
1989).
Despite
their
significance,
past
studies
have
shown
that
conch
populaCons
are
being
depleted
and
they
are
vulnerable
to
collapse
due
to
overfishing
throughout
their
range.
Less
are
being
found,
and
studies
of
middens
(a
group
of
discarded
of
conch
shells,
Fig.
4)
also
show
a
significant
increase
in
the
illegal
harvest
of
juvenile
queen
conch
(Clark
et
al.
2005).
Furthermore,
they
are
not
being
sufficiently
protected
because
there
are
no
marine
protected
areas,
closed
seasons,
adequate
regulaCons,
or
even
enforcement
of
the
current
regulaCons.
(Danlychuck,
2005).
Past
studies
have
shown
that
it
is
inadequate
to
only
protect
adult
conch
because
in
order
to
increase
the
populaCon,
juveniles
must
have
the
opportunity
to
mature
and
reproduce.
However,
studies
also
indicated
that
in
South
Eleuthera,
juvenile
densiCes
in
nursery
grounds
are
relaCvely
high.
This
suggests
that
nursery
grounds
might
be
good
target
areas
to
protect
so
that
conch
have
the
chance
to
fully
mature
(Clark
et
al.
2005).
Methods – midden surveys
• Randomly
selected
20
shells
from
each
midden
• Measured
the
siphonal
length
and
lip
thickness
(if
present)
(Fig.
7)
• Recorded
data
Acknowledgements
We
would
like
to
thank
Claire
Thomas,
Becky
Clough,
Cape
Eleuthera
InsCtute,
The
Island
School,
and
everyone
who
helped
us
with
our
transects.
A
total
of
153
queen
conch
were
found
in
walking
transects
along
shorelines
conducted
in
South
Eleuthera,
The
Bahamas.
Of
the
6
sites,
2
were
on
the
AtlanCc
and
4
were
on
the
Exuma
Sound
side.
The
mean
area
per
survey
was
25,000
m2
off
the
shoreline
and
overall
we
covered
149,328
m2
or
14.9
ha.
Of
the
153
queen
conch
idenCfied,
7
were
adults
and
146
were
juveniles.
The
largest
aggregaCon
observed
was
69
juveniles
in
Half
Sound
North
on
the
AtlanCc
side
(Fig.8
&
9).
Besides
geographic
locaCon,
we
also
looked
at
habitat
and
substrate
type.
According
to
our
findings,
the
highest
densiCes
of
conch
were
located
in
areas
with
bo2om
types
of
seagrass
and
a
combinaCon
of
sand
and
seagrass
(Fig.
10).
Finally,
our
midden
surveys
showed
that
42
(52.5%)
of
the
conch
were
legally
harvested
and
38
(47.5%)
were
illegally
harvested
(Fig.
11).
The
purpose
of
our
study
was
to
observe
where
aggregaCons
of
juvenile
queen
conch
are
located
to
idenCfy
essenCal
nursery
grounds.
We
hypothesized
that
most
juvenile
queen
conch
in
South
Eleuthera
would
be
found
in
habitats
of
seagrass
and
sand,
similar
to
previous
studies
(Stoner,
1989).
The
findings
from
juvenile
surveys
supported
our
hypothesis,
as
most
of
the
observed
juveniles
were
in
habitats
with
seagrass
and
a
mix
of
sand-­‐seagrass
substrate
(Fig.
10;
Fig.
12;
Fig.
13).
Therefore,
sand
and
seagrass
are
the
preferred
bo2om
types
of
juvenile
queen
conch
in
South
Eleuthera,
which
is
novel
informaCon
for
the
area.
TargeCng
these
habitat
types
could
also
potenCally
contribute
to
future
management
plans
or
conservaCon
strategies,
such
as
the
implementaCon
of
a
marine
protected
area.
The
results
from
midden
surveys
provide
supporCng
evidence
that
juveniles
are
being
harvested,
since
almost
half
(48%)
of
the
queen
conch
we
surveyed
were
illegally
harvested
juveniles.
These
findings
emphasize
the
importance
of
protecCng
juveniles
and
their
habitats
from
overharvesCng,
as
well
as
providing
new,
important
data
on
the
prevalence
of
illegal
fishing
in
South
Eleuthera.
Overall,
this
new
data
can
be
used
to
protect
the
juveniles
in
hopes
of
maintaining
or
increasing
current
queen
conch
populaCons.
Future
Direc/ons:
In
the
future,
the
Queen
Conch
Research
Team
can
try
to
increase
awareness
about
conch’s
ecological
importance,
their
decline,
and
the
negaCve
repercussions
of
harvesCng
juveniles
in
local
communiCes.
Research
can
be
done
on
adult
conch
during
the
summer
breeding
months
as
it
is
also
an
important
life
stage
to
protect.
Also,
more
juvenile
surveys
can
be
done,
to
increase
the
area
surveyed
on
the
AtlanCc
side
of
the
island,
and
to
add
this
data
to
the
map
being
used
to
inform
management
on
areas
to
protect.
Discussion
Results
Fig
8
-­‐
The
conch
research
team
in
Half
Sound
North
Fig
5
-­‐
The
conch
research
team
doing
a
transect
on
Sunrise
Beach
Fig
7
-­‐
Measuring
the
lip
thickness
of
a
discarded
conch
shell
Fig
6
-­‐
Measuring
the
siphonal
length
of
a
live
conch
Figures
Figure
10
–
The
number
of
queen
conch
observed
in
each
bo2om
type
(sand,
seagrass,
sand/seagrass,
algae,
and
rock)
in
South
Eleuthera,
Bahamas
in
the
Spring
2013.
Figure
9
–
Map
showing
6
transect
sites
where
juvenile
conch
aggregaCons
were
idenCfied
on
South
Eleuthera,
The
Bahamas
in
Spring
2013
Figure
11
–
Comparing
midden
legally
harvested
(with
a
flared
lip)
to
illegally
harvested
queen
conch
in
South
Eleuthera,
Bahamas
in
the
Spring
of
2013.
0
10
20
30
40
50
60
70
80
Sand
Seagrass
Sand/Seagrass
Algae
Rocky
#
of
Queen
Conch
BoBom
Type
Fig
12
–
A
conch
in
seagrass
substrate
Fig
13
–
A
conch
in
sand
substrate