TY - JOUR
T1 - Prey capture in long-jawed butterflyfishes (Chaetodontidae)
T2 - The functional basis of novel feeding habits
AU - Ferry-Graham, Lara A.
AU - Wainwright, Peter C.
AU - Bellwood, David R.
N1 - Funding Information:
We thank J. Grubich, T. Waltzek, D. Hulsey, D. Bolnick, A. Carroll, S. Schenk, M. Graham and one anonymous reviewer for insightful discussions and helpful feedback on this manuscript. M. Foster, J. Grubich and A. Carroll assisted with collecting video data. P. Motta loaned us valuable specimens and made insightful comments on the manuscript and at several stages of this research. We thank River City Aquatics (Sacramento, CA, USA), and Quality Marine Tropicals (Los Angeles, CA, USA), B. Squire of Cairns Marine Aquarium Fish (Cairns, Australia), R. Tunin and T. Waltzek for their advice and assistance in locating specimens. I. Hart skillfully produced the anatomical drawings. The Adaptive Optics video system used in Australia was purchased under NSF grant IBN-9306672 to PCW, and this research was supported by a grant from the Australian Research Council to DRB and PCW. [SS]
PY - 2001/1/31
Y1 - 2001/1/31
N2 - Several species of butterflyfishes (Chaetodontidae) possess extremely elongate jaws, and feed mostly by probing the benthos and biting off pieces of attached invertebrates. In contrast, Forcipiger longirostris, the longest-jawed chaetodontid, exhibits a novel pattern of prey use, feeding almost exclusively on small caridean shrimp, a mobile and highly elusive prey type that lives within the structure of coral reefs. We explored the functional basis of this novel pattern of prey use by comparing prey capture kinematics in this and four other butterflyfish species, including two other species that possess elongate jaws. High speed video recordings of feeding events on live adult brine shrimp were analyzed from individuals of five species: Forcipiger longirostris, F. flavissimus, Chelmon rostratus, Heniochus acuminatus, and Chaetodon xanthurus. We focused on a comparison among species of the relative contribution of "suction", measured as the amount of movement of the prey toward the predator's mouth, and "ram", measured as the distance moved by the predator toward the prey during the strike. All five species utilized a combination of suction and ram while feeding on brine shrimp. The contribution of suction did not differ significantly among species. However, F. longirostris exhibited a ram contribution to the strike that was more than twice that seen in any of the other species, permitting this species to initiate strikes from the greatest initial predator-prey distance. F. longirostris is known to possess a major structural novelty in the feeding mechanism that permits anterior movement of the entire jaw apparatus. The ability of this species to feed successfully on elusive prey appears to be related to exceptional jaw protrusion, resulting in greater use of ram during prey capture. This ability to protrude long, slender jaws toward the prey may allow it to move the jaws without detection within close enough proximity of the prey to then permit the effective use of suction. The use of extensive ram in this manner by small-mouthed fishes may be more widespread than previously thought.
AB - Several species of butterflyfishes (Chaetodontidae) possess extremely elongate jaws, and feed mostly by probing the benthos and biting off pieces of attached invertebrates. In contrast, Forcipiger longirostris, the longest-jawed chaetodontid, exhibits a novel pattern of prey use, feeding almost exclusively on small caridean shrimp, a mobile and highly elusive prey type that lives within the structure of coral reefs. We explored the functional basis of this novel pattern of prey use by comparing prey capture kinematics in this and four other butterflyfish species, including two other species that possess elongate jaws. High speed video recordings of feeding events on live adult brine shrimp were analyzed from individuals of five species: Forcipiger longirostris, F. flavissimus, Chelmon rostratus, Heniochus acuminatus, and Chaetodon xanthurus. We focused on a comparison among species of the relative contribution of "suction", measured as the amount of movement of the prey toward the predator's mouth, and "ram", measured as the distance moved by the predator toward the prey during the strike. All five species utilized a combination of suction and ram while feeding on brine shrimp. The contribution of suction did not differ significantly among species. However, F. longirostris exhibited a ram contribution to the strike that was more than twice that seen in any of the other species, permitting this species to initiate strikes from the greatest initial predator-prey distance. F. longirostris is known to possess a major structural novelty in the feeding mechanism that permits anterior movement of the entire jaw apparatus. The ability of this species to feed successfully on elusive prey appears to be related to exceptional jaw protrusion, resulting in greater use of ram during prey capture. This ability to protrude long, slender jaws toward the prey may allow it to move the jaws without detection within close enough proximity of the prey to then permit the effective use of suction. The use of extensive ram in this manner by small-mouthed fishes may be more widespread than previously thought.
KW - Functional morphology
KW - Jaw protrusion
KW - Prey capture
KW - Ram feeding
KW - Specialist
KW - Suction feeding
UR - http://www.scopus.com/inward/record.url?scp=0035977592&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0035977592&partnerID=8YFLogxK
U2 - 10.1016/S0022-0981(00)00312-9
DO - 10.1016/S0022-0981(00)00312-9
M3 - Article
AN - SCOPUS:0035977592
SN - 0022-0981
VL - 256
SP - 167
EP - 184
JO - Journal of Experimental Marine Biology and Ecology
JF - Journal of Experimental Marine Biology and Ecology
IS - 2
ER -