Journal of Fish Biology,
Journal Year:
2024,
Volume and Issue:
unknown
Published: May 9, 2024
Abstract
Marine
predators
are
vital
to
the
healthy
functioning
of
coastal
ecosystems,
but
understand
their
roles,
it
is
necessary
elucidate
movement
ecology,
particularly
in
relation
one
another.
A
decade's
worth
acoustic
telemetry
data
(2011–2020)
from
Algoa
Bay,
South
Africa,
was
investigated
determine
how
two
mesopredatory
species
(teleosts:
dusky
kob
Argyrosomus
japonicus
,
n
=
11,
and
leervis
Lichia
amia
16)
top
predatory
(sharks:
ragged‐tooth
sharks
Carcharias
taurus
45,
white
Carcharodon
carcharias
31)
used
shared
this
bay
ecosystem.
Multi‐annual
seasonal
fidelity
exhibited
by
all
species,
differences
residency
were
observed
among
species.
Similarly,
space
differently—the
teleosts
moved
less
had
movements
restricted
central
western
inshore
regions
bay.
Conversely,
roamed
more,
detections
concentrated
part
for
C
.
eastern
Social
network
analysis
showed
that
segregated
time
on
a
fine
scale.
However,
there
some
interaction
between
L
varying
degrees.
This
likely
because
strong
habitat
preferences
each
predator–prey
relationships
these
guilds.
Results
highlight
sheltered
marine
Bay
resource‐rich
environment,
supporting
multiple
with
different
hunting
strategies
albeit
similar
prey
preferences.
Finally,
afforded
protection
current
Greater
Addo
Elephant
National
Park
Protected
Area
vulnerable
fishing
pressure
when
they
leave
Journal of Fish Biology,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 3, 2025
The
great
hammerhead
shark
(Sphyrna
mokarran)
is
a
highly
mobile
species
whose
population
in
the
United
States
declined
dramatically
through
early
2000s.
Their
spatial
ecology
poorly
understood,
creating
challenges
for
effective
conservation
of
this
enigmatic
marine
predator.
Using
acoustic
telemetry
and
network
analyses,
we
describe
movement
patterns
15
mature
sharks
(207-331.5
cm
fork
length)
primarily
within
waters
southeastern
from
April
2019
to
December
2022,
including
identifying
corridors,
core
use
areas
seasonal
shifts
habitat
use.
Great
hammerheads
exhibited
partial
migration;
some
undertook
consistent,
repeatable,
round-trip
migrations
between
tagging
site
Florida
Keys
northern
points
Gulf
Mexico
Atlantic
coast.
Conversely,
others
remained
year-round.
Network
analysis
coupled
with
community
detection
algorithms
revealed
that
individual
displayed
oceanic
basin
affinity,
favouring
migration
either
Ocean
or
Mexico.
shifted
their
seasonally
inshore
channels
(spring
summer)
offshore
artificial
reefs
natural
reef
tract
(summer
winter).
These
may
be
driven
by
prey
availability,
as
often
corresponded
known
locations
spawning
aggregations
fish.
data
fill
an
important
knowledge
gap
migratory
can
improve
management
strategies
historically
overexploited
species.
We
discuss
importance
drawing
upon
multiple
management,
particularly
designation
essential
fish
habitat.
Canadian Journal of Fisheries and Aquatic Sciences,
Journal Year:
2024,
Volume and Issue:
81(5), P. 600 - 619
Published: Feb. 9, 2024
Regulated
waterways,
interconnected
by
navigation
barriers
(locks
and
dams),
are
uniquely
difficult
to
manage,
given
interest
in
enabling
native
species
connectivity
while
minimizing
invasions.
Canada's
historic
Rideau
Canal
Waterway,
a
202
km
navigable
route
located
eastern
Ontario
connected
24
lockstations,
embodies
this
challenge.
The
lock(s)
water-control
dam
that
compose
each
lockstation
may
respectively
offer
pathway,
though
what
extent
is
unclear.
We
used
acoustic
telemetry
(native
largemouth
bass
(
Micropterus
nigricans)
northern
pike
Esox
lucius),
invasive
common
carp
Cyprinus
carpio);
n
=
224)
evaluate
fish
relative
lock
operations
environmental
data
over
three
years
(2019–2021).
Thirty-five
passages
23
fishes
were
recorded,
with
49%
of
through
locks.
No
detected;
movements
indicate
they
favour
higher
flow
areas
downstream
dams,
regions
no
pathway
upstream.
Most
and,
concern
obligate
upstream
migrators,
we
found
multi-flight
higher-lift
locks
appear
impassable
movements.
Our
results
suggest
these
lockstations
limit,
but
not
entirely
restrict,
connectivity.
Journal of Fish Biology,
Journal Year:
2024,
Volume and Issue:
unknown
Published: May 9, 2024
Abstract
Marine
predators
are
vital
to
the
healthy
functioning
of
coastal
ecosystems,
but
understand
their
roles,
it
is
necessary
elucidate
movement
ecology,
particularly
in
relation
one
another.
A
decade's
worth
acoustic
telemetry
data
(2011–2020)
from
Algoa
Bay,
South
Africa,
was
investigated
determine
how
two
mesopredatory
species
(teleosts:
dusky
kob
Argyrosomus
japonicus
,
n
=
11,
and
leervis
Lichia
amia
16)
top
predatory
(sharks:
ragged‐tooth
sharks
Carcharias
taurus
45,
white
Carcharodon
carcharias
31)
used
shared
this
bay
ecosystem.
Multi‐annual
seasonal
fidelity
exhibited
by
all
species,
differences
residency
were
observed
among
species.
Similarly,
space
differently—the
teleosts
moved
less
had
movements
restricted
central
western
inshore
regions
bay.
Conversely,
roamed
more,
detections
concentrated
part
for
C
.
eastern
Social
network
analysis
showed
that
segregated
time
on
a
fine
scale.
However,
there
some
interaction
between
L
varying
degrees.
This
likely
because
strong
habitat
preferences
each
predator–prey
relationships
these
guilds.
Results
highlight
sheltered
marine
Bay
resource‐rich
environment,
supporting
multiple
with
different
hunting
strategies
albeit
similar
prey
preferences.
Finally,
afforded
protection
current
Greater
Addo
Elephant
National
Park
Protected
Area
vulnerable
fishing
pressure
when
they
leave
