OLLA and SAMET: COURTSHIP AND SPAWNING BEHAVIOR OF TAUTOG 



Beginning anywhere from 2 to 5 min before 

 spawning, the female began swimming back and 

 forth along the length of the tank close to the sand 

 using only the pectoral fins, a behavior we defined 

 as a run. A run was usually accompanied by a full 

 and constant erection of the dorsal fin and the final 

 shading development in which all of the white 

 areas of her body (i.e., the saddle, caudal stripes or 

 white portions of the checkerboard pattern, the 

 "eyebrows," and the anterior half of the dorsal fin) 

 were almost totally blanched, sometimes colored 

 with a yellowish hue. Then, as a run was either 

 beginning or in progress, the caudal fin was rigidly 

 flexed upward one final time (Figure lc), exposing 

 the maximally dilated vent, while at the same 

 time the head was tilted downward. The female's 

 swimming in this position seemed awkward, re- 

 sulting in her moving with a characteristic wobble 

 or wiggle. The female made one or two runs alone 

 which apparently served to heighten the attention 

 of the dominant male, for he would break off other 

 activities (e.g., chasing the subordinate male, 

 swimming randomly about the tank) to usually 

 rush her first and then to follow her (Figure 2a). 



As the female continued on the runs, the male 

 tended to swim more in a parallel alignment with 

 her. Eventually he swam just slightly behind with 



his head moving closer to the female's operculum 

 or midsection, 30 to 40 cm away from her ( Figure 

 2b). Then suddently, while increasing her speed by 

 changing from pectoral swimming to caudal 

 thrusts, the female swam rapidly toward the sur- 

 face, with the male immediately accelerating in a 

 similar manner to keep apace with her i Figure 2c). 

 The angle of their ascent was anywhere from 40° 

 to 70°. When the fish were less than a meter from 

 the surface and while still swimming rapidly, they 

 turned their bodies so that their ventral areas 

 faced toward each other. On those occasions when 

 the fish's movements were perfectly coordinated, 

 the pectorals of the male appeared to be embracing 

 the female (Figure 2d). With the animals in con- 

 tact, they arched their bodies into U-shapes and 

 released gametes either before reaching the sur- 

 face or as they broke the surface (Figure 2e). Then 

 the pair separated and swam downwards (Figure 

 2f ), with the female coming to rest on the sand 

 where the male usually rushed her 2 or 3 times 

 within 5 to 10 s following the spawning. After a 

 spawning, the female's shading usually regressed 

 to just a thin saddle within a few minutes. 



The spawning as we have described it appeared 

 to comprise the prevalent mode of gamete release. 

 However, there occurred slight variations in the 



FIGURE 2. — Final sequence of behaviors leading to spawning in Tautoga onitis: a) male approaches female; b) they swim parallel with 

 female slightly ahead; c) male and female move upwards in the water column; d) the pair orient to each other in a ventral-to-ventral 

 alignment; e) with bodies flexed the pair release gametes as they break the water surface; f )the fish separate and move downwards. 



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