TWO TYPES OF DIURNAL VERTICAL MIGRATIONS OF COD (Dva Tipa Sutochnykh Vertikalnykh Migratsii Treski),
Abstract
As other carnivores, the cod pursues fishes mainly during the night or at dawn. This has also been demonstrated by aquatorial observations. Capelin, one of the major food items of cod, migrates to higher strata in the evening. The cod, affected by changes in illumination rises to the surface. Thus, it follows the pattern of the first type of vertical migration. The sand eel spawns on the bottom for days. The night carnivore cod hunts for the eel in nighttime. Therefore, trawl catches contain large quantities of cod. In daytime the cod migrates to higher strata, the ones that remain in bottom layer continue to feed on the benthos at somewhat more intense rate than at night. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1970
- Accession Number
- AD0709324
Entities
People
- K. G. Konstantinov
- T. N. Turuk
Organizations
- Naval Oceanographic Office