Abundance, Behaviour and Distribution Pattern

Metabolic rhythms underlie population dynamics, behaviour and distribution, despite their complicated nature. As a corollary, the influences of abundance and complex behaviour patterns on metabolism are equally important. The relationship between metabolism and population dynamics appears to be simple. Nikolsky (1974) regarded recruitment, adult stock, total mortality and food supply as interdependent parts of the whole. 

Recruitment of a species depends on the abundance of the brood. Abundance, in its turn, is influenced by the fertility of the population and by the quality of the reproductive products. Such quality comprises specific features of the genome and the content of plastic (proteins, phospholipids and cholesterol) and energy (triacyl-glycerols, wax esters and glycogen) 

An increased stock of recruits, resulting from the effects of a better food supply on the parent fish, will deplete the food supply available to the population. This poorer food supply will reverse the entire process, reducing energy stores, growth rate of the fish, quality and quantity of reproductive products and, finally, the total numbers of the population. The reduced numbers of fish, assuming that the food supply remains more or less stable, are then able to eat 

Excessive depletion of lipids, adenyl nucleotides and proteins during wintering may result in mass mortality, especially if the temperature is very low. Many workers have reported a relationship between the energy reserves at 

In the section devoted to daily rhythms, we introduced the idea of a biological clock . Here we deal with a biological calendar over the annual period. It is based on an ecological trigger which launches each stage, the key factor here being the photoperiod. Any population, be it of fish, birds or other 

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