102
J.H. Choat
body dimensions such as gape, body depth and body length as a proxy for locomotory, foraging and feeding patterns has been verifi ed by more detailed studies on
perciform fi shes that have related body dimensions to functional morphology (Collar
and Wainwright 2009 ) . Body dimensions also infl uence reproductive biology.
Sadovy ( 1996 , Fig. 2.6) established a relationship between reproductive output
and body form demonstrating that fi shes with high levels of lateral compression
(estimated as cross sectional ratio) had lower relative fecundity at any one time than
those with fusiform body profi les at comparable lengths.
The argument that body architecture, size and internal anatomy will constrain
ovary size and be associated with more frequent spawning episodes with smaller
egg releases per episode has been suggested by a number of authors (Robertson
1991 ; Choat and Bellwood 1991 ; Sadovy 1996 ) . In addition, body depth and lateral
compression are linked to habitat associations, maneuverability and swimming
speed in reef fi shes (Fulton 2007 ) . Fishes with high levels of lateral compression
are associated with reef crests, may swim rapidly, primarily with pectoral fi ns
(labriform) and feed on benthic resources. In contrast, representatives of fi sh with
lower levels of lateral compression (snappers and groupers) are associated with
deeper and more sheltered waters and swim primarily by body and caudal fi n movements (sub-carangiform) (Fulton and Bellwood 2005 ; Fulton 2007 ) . Small gape
size in the surgeonfi shes and parrotfi shes is associated with rapid and continuous
feeding and is associated with modifi ed jaw architecture and the capacity to deliver
a more powerful bite (Wainright et al. 2004 ; Konow et al. 2008 ; Price et al. 2010 ) .
The combination of a more elongate body and wider gape has been clearly linked to
a predatory feeding mode with those species at the upper ends of the range being
piscivores (Collar and Wainwright 2009 ) .
The fi rst analysis in this section focuses on morphology and biology relevant to
aggregative spawning; size, body architecture, foraging and swimming mode and
trophic biology. PC 1 was associated with increasing size and explained most of the
observed pattern (Fig. 4.3a ). The analysis retrieved three groups; (1) snappers and
groupers where increasing body length was associated with a loss of laterally compressed body form resulting in fusiform shapes. Smaller snappers (Dory snapper L.
fulvifl amma ) were more laterally compressed than the larger members of this family.
The greatest sizes were achieved by the groupers with a characteristically large gape;
(2) parrotfi shes and (3) surgeonfi shes; these share a small gape relative to head length
with the degree of lateral compression greater in surgeonfi shes which separated from
the parrotfi shes along this axis. Reduced gape was associated with a smaller body
size and a tendency for higher levels of lateral compression.
These patterns identify differences in feeding, swimming and foraging behaviour.
Species with high lateral compression occur in shallow turbulent reef habitats using
pectoral fi n swimming modes to achieve high swimming speeds and maneuverability
(Fulton 2007 ) . Snappers and groupers with a more fusiform body occur in habitats
with less water movement and swim at slower speeds using a sub-carangiform
swimming mode (Fulton 2005, 2007 ; Fulton and Bellwood 2005 ) . However it is
unclear how the different body forms and swimming modes perform under conditions of extended episodes of migratory swimming as seen in many transient spawning
J.H. Choat
body dimensions such as gape, body depth and body length as a proxy for locomotory, foraging and feeding patterns has been verifi ed by more detailed studies on
perciform fi shes that have related body dimensions to functional morphology (Collar
and Wainwright 2009 ) . Body dimensions also infl uence reproductive biology.
Sadovy ( 1996 , Fig. 2.6) established a relationship between reproductive output
and body form demonstrating that fi shes with high levels of lateral compression
(estimated as cross sectional ratio) had lower relative fecundity at any one time than
those with fusiform body profi les at comparable lengths.
The argument that body architecture, size and internal anatomy will constrain
ovary size and be associated with more frequent spawning episodes with smaller
egg releases per episode has been suggested by a number of authors (Robertson
1991 ; Choat and Bellwood 1991 ; Sadovy 1996 ) . In addition, body depth and lateral
compression are linked to habitat associations, maneuverability and swimming
speed in reef fi shes (Fulton 2007 ) . Fishes with high levels of lateral compression
are associated with reef crests, may swim rapidly, primarily with pectoral fi ns
(labriform) and feed on benthic resources. In contrast, representatives of fi sh with
lower levels of lateral compression (snappers and groupers) are associated with
deeper and more sheltered waters and swim primarily by body and caudal fi n movements (sub-carangiform) (Fulton and Bellwood 2005 ; Fulton 2007 ) . Small gape
size in the surgeonfi shes and parrotfi shes is associated with rapid and continuous
feeding and is associated with modifi ed jaw architecture and the capacity to deliver
a more powerful bite (Wainright et al. 2004 ; Konow et al. 2008 ; Price et al. 2010 ) .
The combination of a more elongate body and wider gape has been clearly linked to
a predatory feeding mode with those species at the upper ends of the range being
piscivores (Collar and Wainwright 2009 ) .
The fi rst analysis in this section focuses on morphology and biology relevant to
aggregative spawning; size, body architecture, foraging and swimming mode and
trophic biology. PC 1 was associated with increasing size and explained most of the
observed pattern (Fig. 4.3a ). The analysis retrieved three groups; (1) snappers and
groupers where increasing body length was associated with a loss of laterally compressed body form resulting in fusiform shapes. Smaller snappers (Dory snapper L.
fulvifl amma ) were more laterally compressed than the larger members of this family.
The greatest sizes were achieved by the groupers with a characteristically large gape;
(2) parrotfi shes and (3) surgeonfi shes; these share a small gape relative to head length
with the degree of lateral compression greater in surgeonfi shes which separated from
the parrotfi shes along this axis. Reduced gape was associated with a smaller body
size and a tendency for higher levels of lateral compression.
These patterns identify differences in feeding, swimming and foraging behaviour.
Species with high lateral compression occur in shallow turbulent reef habitats using
pectoral fi n swimming modes to achieve high swimming speeds and maneuverability
(Fulton 2007 ) . Snappers and groupers with a more fusiform body occur in habitats
with less water movement and swim at slower speeds using a sub-carangiform
swimming mode (Fulton 2005, 2007 ; Fulton and Bellwood 2005 ) . However it is
unclear how the different body forms and swimming modes perform under conditions of extended episodes of migratory swimming as seen in many transient spawning