SHORT COMMUNICATION
Previous exposure to novel prey improves the feeding
success of hatchery-reared spotted seatrout,
Cynoscion nebulosus (Cuvier, 1830) within habitat
structure
Lauren A Jackson
1
, Chet F Rakocinski
2
& Reginald B Blaylock
2
1
Southeast Fisheries Science Center, NOAA, NMFS, Pascagoula, MS, USA
2
Department of Coastal Sciences, The University of Southern Mississippi, Ocean Springs, MS, USA
Correspondence: C F Rakocinski, Department of Coastal Sciences, The University of Southern Mississippi, 703 East Beach Drive,
Ocean Springs, MS 39564, USA. E-mail: chet.rakocinski@usm.edu
As a popular recreational sportfish in the Gulf of
Mexico, the spotted seatrout (Cynoscion nebulosus)
is probably being managed at close to its maxi-
mum sustainable level (Fulford & Hendon 2010).
Consequently, the feasibility of stock enhancement
is being evaluated in Mississippi as part of a com-
prehensive management strategy for this species.
The success of stock enhancement depends on the
ability of newly released hatchery-reared (HR) fish
to acquire the necessary survival skills in terms of
feeding, habitat use and predator avoidance (Hun-
tingford 2004; Leber 2004; Liao 2004). As the
hatchery setting is devoid of natural stimuli, the
ability of HR fish to acclimate to the natural set-
ting requires critical assessments (Olla, Davis &
Ryer 1998; LeVay, Caralho, Quinitio, Lebata, Ut &
Fushimi 2007). Thus, the role of complex habitat
structure should also be considered when evaluat-
ing foraging abilities of HR fish (Salvanes & Brai-
thwaite 2005, 2006).
Unfamiliarity with natural prey and habitat
may impede the survival of HR spotted seatrout by
hindering their feeding success upon release into
the wild. Prior exposure to natural prey may alle-
viate unfamiliarity with foraging under natural
conditions, including structured habitat. To assess
this possibility, the effect of previous exposure to
novel natural prey on the feeding success of HR
fish was evaluated as a treatment effect, crossed
with the presence or absence of structured habitat.
Our objective was to assess the feeding success of
juvenile HR spotted seatrout on novel live prey
(grass shrimp; Palaemonetes spp.) both in the pres-
ence and in the absence of emergent Spartina alter-
niflora within the context of a mesocosm
experiment.
Juvenile spotted seatrout were reared in a recir-
culating system at the USM GCRL Thad Cochran
Marine Aquaculture Center where they had been
maintained on a pelleted diet. All experimental fish
came from the same hatchery cohort and were
163 days old (mean TL and Wt, 17.5 cm and
58.22 g). A predominant food item in the wild,
grass shrimp (Palaemonetes spp.) (Jackson, Rako-
cinski & Blaylock 2013) was used as prey in this
study. Grass shrimp were collected from local
marsh edge habitat for the experiment. Carapace
lengths of one hundred of 720 grass shrimp used
averaged 22.84 Æ 3.72 SD mm.
The experiment was conducted outdoors under
a 5-m-high, 55% shade cloth and maintained at
ambient photoperiod and temperature. The design
comprised twelve 680-L round fibreglass tanks,
each filled with ~500 L of saltwater. To account
for any systematic spatial variation, the spatial
layout was subdivided into three randomized
blocks (i.e. four tanks representing all four
treatments). Tanks within each block were ran-
domly assigned to one of the four treatment com-
binations: (1) experienced fish with no Spartina;
© 2014 John Wiley & Sons Ltd 1
Aquaculture Research, 2014, 1–5 doi: 10.1111/are.12438