A qualitative and quantitative investigation of the behaviour of the longhorn sculpin, Myoxocephalus octodecemspinosus (Mitchill 1815), with special reference to feeding

Behavioural observations of Myoxocephalus octodecemspinosus were made by diving at two locations on the Avalon Peninsula. Qualitative descriptions of the daily activity were compiled with two fundamental postures, REST and ALERT, and four behaviours, rooting, agonism, locomotion, and feeding, being...

Full description

Bibliographic Details
Main Author: Jenkins, Bruce Wayne
Format: Thesis
Language:English
Published: Memorial University of Newfoundland 1974
Subjects:
Online Access:https://research.library.mun.ca/7336/
https://research.library.mun.ca/7336/1/Jenkins_BruceWayne.pdf
https://research.library.mun.ca/7336/3/Jenkins_BruceWayne.pdf
Description
Summary:Behavioural observations of Myoxocephalus octodecemspinosus were made by diving at two locations on the Avalon Peninsula. Qualitative descriptions of the daily activity were compiled with two fundamental postures, REST and ALERT, and four behaviours, rooting, agonism, locomotion, and feeding, being observed. A behavioural profile for the longhorn sculpin was derived from these descriptions. -- Feeding behaviour occurs in a stereotyped pattern, similar in its basic form to the feeding of other marine and freshwater predators. Despite these behavioural characteristics, the longhorn is an ineffective predator of smaller benthic fish species. Field observations indicated that the longhorn is primarily a visual feeder. Laboratory experiments however, revealed that this species also employs other sensory modes for the detection of food. -- Stomach contents, intestinal contents, and occurrence of digestive stages in specimens caught over a 24 hour period, indicated cyclic feeding during the capelin (Mallotus villosus), spawning period. However, an Analysis of Variance (MANOVA), revealed that time was not the most important factor affecting ingestion. -- Caloric analysis of selected prey organisms indicated that capelin, with a value of 5341 calories per gram dry weight, is the most energy rich food resource for inshore populations of the longhorn sculpin. Large scale movements of M. octodecemspinosus to shallower, inshore waters of Newfoundland during the early summer are suggested to be a phenomenon related to the availability of this food resource.