A Study of a Short Term Behaviour Cycle Creeping Through in the Three-Spined Stickleback (Gasterosteus Aculeatus L.) Part 2
Authors: Hart M. 't 
Published: April 2008

A male stickleback with a nest but without eggs in the nest will creep through its nest fairly regularly. When a female in a glass tube is presented to the male, there is a increased chance of Creeping Through. If the female is removed after Creeping Through, the male will creep through in such way that the intervals between the Creepings Through increase in a geometric progression. If the female is not removed (and if it is impossible that she follows the male to the nest), then the intervals between the Creepings Through have the same length. If in this situation the duration of Creeping Through is shortened, either by shortening the nest, or opening the roof of the nest, or interruption of the action of Creeping Through, then the Inter Creeping Through Interval after this shortened Creeping Through, is shortened directly proportional to the shortening of the duration of Creeping Through. If the duration of Creeping Through is lengthened, either by lengthening the nest or by putting a glass-rod on the nest during Creeping Through, the length of the subsequent Inter Creeping Through Interval is not changed. There is a soll-wert for the duration of Creeping Through and the male tends towards this value even when the nest is not of normal length. In a shortened Inter Creeping Through Interval the behaviour is changed in such a way as if the first part of the normal Inter Creeping Through Interval is skipped. Because of the fact that the duration of Creeping Through is determining the length of the subsequent Inter Creeping Through Interval (if not longer than normal), we must assume that the male stickleback is able to register very precisely the duration of Creeping Through. This makes it possible to investigate which form of stimulation could be responsible for this very accurate registration. Five possible forms of exteroceptive and propioceptive stimulation which could be responsible for this registration, (and hence for the refractory period for Creeping Through) were investigated. 1. It was found that if a stimulus-situation which is more or less comparable to the stimulus-situation in the nest during Creeping Through, is presented to the male at the moment Creeping Through has to occur, this does not cause a refractory period for Creeping Through. There is only a refractory period for Creeping Through if the male creeps through a nest, but it is not necessary that the male creeps through its own nest. 2. The refractory period for Creeping Through is not caused by some form of a feedback from either reduction or accumulation during the Inter Creeping Through Interval of a secreted substance which was accumulated or reduced during Creeping Through. 3. Changing of the mechanical pressure of the nest has the effect of interrupting Creeping Through instead of affecting the rate of change of the factor which causes the refractory period for Creeping Through. 4. Tail-beating is not the proprioceptive factor which causes the refractory period for Creeping Through. A male may show less tail-beating than normal during Creeping Through but the subsequent Inter Creeping Through Interval is not shortened in proportion to the decrease of tail-beating but only in proportion to the decrease in the duration of Creeping Through. 5. The possible sensory stimulation of pharynx and/or underside of the body seems to be important in so far as it guarantees that normal Creeping Through behaviour is carried out but this stimulation is not absolutely necessary to produce a refractory period after Creeping Through. It is therefore concluded that no extero- or proprioceptive stimulation could be found which could be responsible for the registration of the duration of Creeping Through.