OLLA and SAMET: COURTSHIP AND SPAWNING BEHAVIOR OF TAUTOG 



studying the cleaning wrasse, Labroides 

 phthirophagus, and Potts (1974) studying the 

 corkwing wrasse, Crenilabrus melops, suggested, 

 may have served as one of the first important vi- 

 sual cues to the male. In addition, the development 

 of the female tautog's saddle, even in its most 

 rudimentary state 2 to 7 wk before the first spawn- 

 ing of each study could have played an important 

 role in identifying the reproductive state of the 

 female. More specifically, the daily transient 

 changes in the saddling would have served to iden- 

 tify the readiness of the female to spawn right up 

 to the moment of spawning. 



The existence and development of reproductive 

 shading patterns in the female tautog is in distinct 

 contrast with the situation found in other labrids 

 in which the conspicuous or bright appearance, 

 when present, is usually found in males (see Roede 

 1972, for review and discussion). Substantiation of 

 the female tautog's spawning pattern was made 

 during an observation with scuba at approxi- 

 mately 1500 (EST) on 26 May 1976 near the Fire 

 Island Coast Guard Station. An adult, gravid 

 female (approximately 45-50 cm) with a well- 

 developed saddle was observed swimming in mid- 

 water along with a dark gray male (A. D. Martin 

 pers. commun.). (Turbidity and the fact that the 

 pair moved away from the diver prevented any 

 further observations.) 



Another major difference between tautog and 

 other labrids regarding coloring or shading is that 

 the shading change of the female was a dynamic, 

 transient process each day. This kind of shading 

 change in tautog falls within the category of 

 physiological color changes discussed by Roede 

 (1972), which reflect rapid alterations in shading 

 and which are also reversible processes. Con- 

 versely, the descriptions of color patterns in other 

 labrids all appear to reflect morphological color 

 changes, which develop only gradually within 

 each individual and particularly within discrete 

 life phases or stages. 



In concert with these shading changes were ac- 

 tions of the female that apparently served to en- 

 hance or facilitate the male's perception of these 

 visual stimuli. For example, the final sustained 

 erection of the female's dorsal fin further enlarged 

 the white area of the saddle. Lifting of the female's 

 caudal fin, occurring when the saddle and caudal 

 pattern were maximally developed, was mani- 

 fested in the final moment before spawning. This 

 lift, coupled with the female's swimming near the 

 male in such a fashion as to expose the dilating 



vent, provided another stimulus towards which 

 the male could orient. 



Visual shading cues arising from the dominant 

 male appeared to be minimal except perhaps for 

 the lightening of its face and lips. These features 

 may have provided a stimulus to the female indi- 

 cating the male's motivation to court and spawn, 

 particularly during rushes directed at the female's 

 head. The stimulus value of the male's white lips 

 during courtship displays in Crenilabrus melops 

 has also been suggested by Potts (1974). 



The obvious visual cues of the male, arising 

 from its rapid approach during a rush, were quite 

 likely a primary source of stimulation to the 

 female. It is also possible that there was a second- 

 ary, lateral-line stimulation, created by the force 

 of the water currents as the male rushed by and 

 which may have enhanced the overall response of 

 the female. Other potential stimuli arising from 

 either of the mates may have been chemosensory 

 in origin. We have no basis at this point to conjec- 

 ture whether or not the animals released and/or 

 perceived any chemical products (i.e., phero- 

 mones), which may have functioned to facilitate 

 reproduction. 



An important indicator of the approaching onset 

 of the reproductive season was the change in be- 

 havior of the dominant male towards the female. It 

 gradually ceased being aggressive to the female, 

 initiated courtship rushes, and permitted her un- 

 restricted access to any area of the tank. This 

 behavioral transition from aggressive to courtship 

 activities is very similar to that observed in Cren- 

 ilabrus melops (Potts 1974). In this species, which 

 pair spawn at a nest site, the nesting male is ag- 

 gressive to both males and females at the onset of 

 the reproductive period. Eventually, however, in- 

 stead of approaching a female to chase or bite her, 

 the male performs an exaggerated courtship, 

 swimming around the female which apparently 

 stimulates her to approach the male and his nest. 



As with many other species, each of the court- 

 ship activities of the tautog seem to serve one 

 major purpose, which was the gradual excitation 

 and synchronization of the partners prior to the 

 spawning each day. In the extended period before 

 the very first spawning of the season, the domi- 

 nant male appeared to assume the more physically 

 active role in the early courtship, primarily by 

 rushing the female. While the female did occa- 

 sionally follow after or rest near him, she did not 

 perform any obvious (ritualized) activities. 

 Nevertheless, even the slight shading changes in 



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