Ecological study of gas fields in the northern Adriatic. 11. Ecological characteristics of the pelagic community
Abstract
On the basis of the studied material from March 1986, as well as previously obtained statistical data, new characteristics of the pelagic community have been shown. Due to their behaviour, organisms of this community were observed on a wider area as to better define the area of IVANA and IKA gasfields.
This paper brings facts on the temporal and spatial distribution of primary production, concentration of chlorophyll a, zooplankton and bacterioplankton.
The main species of small pelagic fish (sardine, sprat, anchovy) were observed bearing in mind the seasonal and spatial movement and their concentration.
The absolute abundancy of sardine stock was determined. Analyses of the catch were performed considering the agregation level of the population.
The length, isometric growth of the length and weight were studied, as well as FOULTON's condition coefficient, and the relations between the sexes of small pelagics.
