Courtship, locomotion, feeding, and miscellaneous behaviour of pacific bonito (Sarda chiliensis)
| Autor: | John H. Prescott, John J. Magnuson |
|---|---|
| Rok vydání: | 1966 |
| Předmět: |
Male
Movement Sexual Behavior media_common.quotation_subject Sarda chiliensis Captivity Zoology Yawn Courtship Swimming behaviour Agonistic behaviour medicine Animals Ecology Evolution Behavior and Systematics media_common biology Pacific bonito Fishes Direct observation Anatomy biology.organism_classification Food Female Animal Science and Zoology medicine.symptom Locomotion |
| Zdroj: | Animal Behaviour. 14:54-67 |
| ISSN: | 0003-3472 |
| DOI: | 10.1016/s0003-3472(66)80011-8 |
| Popis: | Summary Establishment of Pacific bonito ( Sarda chiliensis (Cuvier) in captivity at Marineland of the Pacific, Palos Verdes, California, has made it possible to study and describe in detail their swimming, feeding, courtship, and miscellaneous behaviours. The oval tank in which the fish were kept was 33 m long, 16·3 m wide, and 11 m deep at the deepest point. Sea water was pumped from the ocean and was held at 22°C. Fish were viewed through 170 windows in the sides of the tank. The oval tank was part of a public display, a circumstance which limited experimental manipulation of the fish. Swimming speeds and tail-beat frequencies were measured from movie films and direct observation. Frequencies of behaviour patterns were recorded either as the numbers observed among all fish by a stationary observer over 10 min periods or the number observed for a single fish for periods of time averaging 71 sec. With the latter method, data were kept separately for individual fish. They swam continuously against the current at an average speed of 88·2 cm/sec and at a tailbeat frequency of 1·42 beats/sec when not feeding or courting. The linear regression of speed ( y ) in body lengths/sec on the number of tail beats/sec ( x ) was y=0·4905+0·6394 x among feeding S. chiliensis . When food (frozen osmerids) was tossed onto the surface, S. chilensis was the first species to reach and ingest it. During feeding, schooling was disrupted, and each S. chiliensis took on a vertically barred coloration and a yellowish middorsal stripe. Courtship included temporary pairing, aggressive defense of females by males, and a sequence of behaviour leading to the simultaneous and adjacent release of gametes. A wobbling swimming motion by a female released a following by males, and likewise, if a male swam immediately behind a female, she began a wobbling type of swimming. Sexual discrimination was mediated by the wobbling and following movements. If more than one male was in the following position, agonistic behaviour occurred which included the transient vertically barred coloration observed in both sexes at feeding time. During courtship, only males assumed the coloration. Gametes were released during a circle swimming behaviour in which the female with the male in tandem swam in a circular path about three body lengths in diameter. If aggression occurred during the wobbling-following portion of the sequence, the sequence usually terminated and did not result in circle swimming and spawning. S. chiliensis had nine miscellaneous behaviour patterns: mouth closure (long), mouth closure (short), snap, yawn, quick swim, lean, bend, jerk, and defecation. Often such movements have been considered as comfort movements, but in the present paper each was discussed separately in terms of association with some vital process of the fish. Mouth closure (long) movements may be associated with olfaction or gill ventilation; snaps following a yawn or a quick swim may be a drinking movement; leans may be a social releaser in schooling; and bends and jerks may be associated with passage of food through the alimentary canal. |
| Databáze: | OpenAIRE |
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