Behavioural and evolutionary ecology of fishes: conflicting demands during the breeding season

Constructed a series of 3 stochastic dynamic-programming models that explore conflicting demands in terms of tradeoffs between present and future reproduction. State variables were parental state (energy reserves) and nest state (number and age of offspring). Tradeoffs were built in as behaviour dependent coefficients that reduce parental and offspring survival, and as behaviour dependent increments or decrements to parental energy reserves. As parental energy reserves increase, courtship and parental care both increase, whereas feeding decreases. However, as offspring number or age increases, parental care increases, and mating and feeding both decrease. Thus, with respect to parental state, feeding is traded off against reproduction (mating and caring); but with respect to nest state, mating and caring are traded off against each other. -from Author