Mechanisms of benthic prey capture in wrasses (Labridae)

Teleost fishes capture prey using ram, suction, and biting behaviors. The relative use of these behaviors in feeding on midwater prey is well studied, but few attempts have been made to determine how benthic prey are captured. This issue was addressed in the wrasses (Labridae), a trophically diverse lineage of marine reef fishes that feed extensively on prey that take refuge in the benthos. Most species possess strong jaws with stout conical teeth that appear well-suited to gripping prey. Mechanisms of prey capture were evaluated in five species encompassing a diversity of feeding ecologies: Choerodon anchorago (Bloch, 1791), Coris gaimard (Quoy and Gaimard, 1824), Hologymnosus doliatus (Lacepède, 1801), Novaculichthys taeniourus (Lacepède, 1801) and Oxycheilinus digrammus (Lacepède, 1801). Prey capture sequences were filmed with high-speed video at the Lizard Island Field Station (14°40′S, 145°28′E) during April and May 1998. Recordings were made of feeding on pieces of prawn suspended in the midwater and similar pieces of prawn held in a clip that was fixed to the substratum. Variation was quantified among species and between prey types for kinematic variables describing the magnitude and timing of jaw, hyoid, and head motion. Species differed in prey capture kinematics with mean values of most variables ranging between two and four-fold among species and angular velocity of the opening jaw differing seven-fold. The kinematics of attached prey feeding could be differentiated from that of midwater captures on the basis of faster angular velocities of the jaws and smaller movements of cranial structures which were of shorter duration. All five species used ram and suction in combination during the capture of midwater prey. Surprisingly, ram and suction also dominated feedings on attached prey, with only one species making greater use of biting than suction to remove attached prey. These data suggest an important role for suction in the capture of benthic prey by wrasses. Trade-offs in skull design associated with suction and biting may be particularly relevant to understanding the evolution of feeding mechanisms in this group.

[1]  K. Liem,et al.  Fishes of the suborder Labroidei lPiscesc Perciformesrc phylogenyc ecologyc and evolutionary significance , 1982 .

[2]  M. Graham,et al.  Statistical significance versus fit: estimating the importance of individual factors in ecological analysis of variance , 2001 .

[3]  M. Alfaro,et al.  Motor Patterns of Herbivorous Feeding: Electromyographic Analysis of Biting in the Parrotfishes Cetoscarus bicolor and Scarus iseri , 1999, Brain, Behavior and Evolution.

[4]  M. Westneat,et al.  Feeding mechanics of teleost fishes (Labridae; Perciformes): A test of four‐bar linkage models , 1990, Journal of morphology.

[5]  Cook,et al.  Ontogeny of feeding morphology and kinematics in juvenile fishes: a case study of the cottid fish Clinocottus analis , 1996, The Journal of experimental biology.

[6]  G. Lauder,et al.  Aquatic prey capture in ray‐finned fishes: A century of progress and new directions , 2001, Journal of morphology.

[7]  S. Norton A functional approach to ecomorphological patterns of feeding in cottid fishes , 1995 .

[8]  P C Wainwright,et al.  Evaluating the use of ram and suction during prey capture by cichlid fishes. , 2001, The Journal of experimental biology.

[9]  Shaw,et al.  Morphological basis of kinematic diversity in feeding sunfishes , 1999, The Journal of experimental biology.

[10]  D. Bellwood,et al.  A functional analysis of grazing in parrotfishes (family Scaridae): the ecological implications , 1990, Environmental Biology of Fishes.

[11]  J. S. Nelson,et al.  Fishes of the world. , 1978 .

[12]  E. Brainerd,et al.  CONVERGENCE IN THE FEEDING MECHANICS OF ECOMORPHOLOGICALLY SIMILAR SPECIES IN THE CENTRARCHIDAE AND CICHLIDAE , 1993 .

[13]  P. Wainwright,et al.  Predicting patterns of prey use from morphology of fishes , 1995, Environmental Biology of Fishes.

[14]  E S Hobson,et al.  Feeding relationships of teleostean fishes on coral reefs in Kona, Hawaii , 1974 .

[15]  R. Tedman Comparative study of the cranial morphology of the labrids Choeroden venustus and Labroides dimidiatus and the scarid Scarus fasciatus (Pisces : Perciformes) I. Head skeleton , 1980 .

[16]  M. Muller,et al.  A quantitative hydrodynamical model of suction feeding in fish , 1982 .

[17]  J. S. Nelson,et al.  Fishes of the World, 3rd Edition , 1994 .

[18]  R. Tedman Comparative study of the cranial morphology of the labrids Choeroden venustus and Labroides dimidiatus and the scarid Scarus fasciatus (Pisces : Perciformes) II. Cranial myology and feeding mechanisms , 1980 .

[19]  G. Lauder,et al.  Feeding biology of sunfishes: patterns of variation in the feeding mechanism , 1986 .

[20]  David R. Bellwood,et al.  Ecomorphology of feeding in coral reef fishes , 2002 .

[21]  W. Rice ANALYZING TABLES OF STATISTICAL TESTS , 1989, Evolution; international journal of organic evolution.

[22]  J. E. Randall,et al.  Fishes of the Great Barrier Reef and Coral Sea , 1955 .

[23]  P. Sale Coral reef fishes : dynamics and diversity in a complex ecosystem , 2002 .

[24]  K. Liem Aquatic Versus Terrestrial Feeding Modes: Possible Impacts on the Trophic Ecology of Vertebrates , 1990 .

[25]  D. W. Strasburg,et al.  Ecological Relationships of the Fish Fauna on Coral Reefs of the Marshall Islands , 1960 .

[26]  Peter C Wainwright,et al.  Feeding mechanism of Epibulus insidiator (Labridae; Teleostei): Evolution of a novel functional system , 1989, Journal of morphology.

[27]  M. Westneat FEEDING, FUNCTION, AND PHYLOGENY : ANALYSIS OF HISTORICAL BIOMECHANICS IN LABRID FISHES USING COMPARATIVE METHODS , 1995 .

[28]  J. E. Randall Food habits of reef fishes of the West Indies , 1967 .

[29]  D. Bellwood,et al.  Modulation of prey capture kinematics in the cheeklined wrasse Oxycheilinus digrammus (Teleostei: Labridae). , 2001, The Journal of experimental zoology.

[30]  S. Norton Capture Success and Diet of Cottid Fishes: The Role of Predator Morphology and Attack Kinematics , 1991 .

[31]  J. H. Zar,et al.  Biostatistical Analysis (5th Edition) , 1984 .

[32]  P. Wainwright,et al.  Motor Basis of Suction Feeding Performance in Largemouth Bass, Micropterus salmoides , 1997 .

[33]  W. K. Gregory Fish Skulls: A Study of the Evolution of Natural Mechanisms , 1933 .

[34]  Mark W. Westneat,et al.  Linkage Biomechanics and Evolution of the Unique Feeding Mechanism of Epibulus Insidiator (Labridae: Teleostei) , 1991 .

[35]  Németh Modulation of buccal pressure during prey capture in Hexagrammos decagrammus (Teleostei: Hexagrammidae) , 1997, The Journal of experimental biology.

[36]  S. L. Sanderson Versatility and specialization in labrid fishes: ecomorphological implications , 1990, Oecologia.

[37]  M. Westneat,et al.  Transmission of force and velocity in the feeding mechanisms of labrid fishes (Teleostei, Perciformes) , 1994, Zoomorphology.