ABLE and MUSICK: LIFE mSTORY AND BEHAVIOR OF LIPARIS INQUILINUS 



length of L. atlanticus during the winter to the 

 replacement of smaller adults by larger adults as 

 the spawning season progressed. This may occur 

 for L. inquilinus , but it seems more likely that 

 sexually immature fish moving inshore in No- 

 vember, December, and January may continue 

 to grow as they become sexually mature. In the 

 laboratory, fish continued to feed during spawn- 

 ing periods. Although the range in total length 

 for collections for each month is large, the varia- 

 tion about and between the means is small (Fig- 

 ure 1). This probably indicates that a single year 

 class is present in each sample. 



Spawning in L. inquilinus probably peaks in 

 March and April. A single collection of L. in- 

 quilinus eggs was made on 9 March 1973, approx- 

 imately 3.5 nautical miles off Holgate, Long 

 Beach Island, N.J. Also, the adult fish rep- 

 resented in Figure 1 were examined for sexual 

 maturity. The percentage of sexually mature fish 

 increased from 12% in January, to 44% in Feb- 

 ruary, and to 67% in March, but decreased to 33% 

 in April, although this last sample was small. 

 Hatching times for other Liparis vary from 22-30 

 days for L. atlanticus (Detwyler 1963) to 6-8 wk 

 forL. liparis (Breder and Rosen 1966). Therefore, 

 the occurrence of L. inquilinus larvae averaging 5 

 mm in May (Figure 1) infers that spawning prob- 

 ably takes place in March and April, and this is in 

 agreement with the time of occurrence of sexually 

 mature adults in inshore waters. 



In the laboratory, reproductive activity and 

 egg laying occurred over many months. During 

 1969, females distended with eggs and performing 

 prespawning behavior (see below) were present 

 from January through August. Eggs with eyed lar- 

 vae were first found in late April and egg masses 

 were found through June. Successful hatching oc- 

 curred only in May. The extensive period of egg 

 deposition and reproductive behavior observed 

 in the laboratory does not agree with the limited 

 reproductive period inferred from field collections. 

 These differences may be attributable to the occa- 

 sional power failures which affected photoperiod, 

 water temperature, and water quality in the 

 laboratory aquaria or simply to laboratory 

 confinement. 



It is likely that the average size of sexually 

 mature males and females is similar and that the 

 sex ratio is 1:1. A single collection of 143 L. in- 

 quilinus (off New England Creek, 7 m, 22 Feb- 

 ruary 1933) contained 75 mature and maturing 

 males (mean 55.3 mm TL, range 37.1-69.6 mm 



TL) and 68 females (mean 54.3 mm TL, range 

 44.3-65.7 mm TL). Neither the ratio of males to 

 females nor the average total length was sig- 

 nificantly different. 



PLANK TONIC 

 LARVAE 



JUVENILES IN 

 SEA SCALLOPS 



Eggs 



407 7 



i t 



JAN FEB MAR APR MAY JUN JUL AuG SEP OCT NOV DEC 



FIGURE 1. — Length-frequency distribution of Liparis inquili- 

 nus collected from the Mid-Atlantic Bight. For each sample, the 

 range is represented by the vertical line, mean by the horizontal 

 line, one standard deviation on each side of the mean by hollow 

 rectangles and two standard errors on each side of the mean 

 by solid rectangles. Numbers above figure are sample sizes. 

 A single collection of L. inquilinus eggs is noted on the hori- 

 zontal £Lxis. 



Female L. inquilinus may spawn more than 

 once. In the laboratory, the abdomen of individual 

 fish was observed to decrease in size as more egg 

 masses were found in aquaria and increase again 

 later. Also the egg diameters in ovaries of females 

 from 16 March 1932 and 1933 usually had two 

 well-defined modes. Fourteen ovaries were ex- 

 amined and most eggs were either 1.00-1.30 or 

 0.01-0.50 mm in diameter. The largest eggs were 

 clear and contained several oil globules and these 

 were more abundant in the center of the ovary. 

 When egg diameter modes in the ovary were not 

 well-defined, egg distribution by size was often 

 random. Counts for the larger eggs ranged from 

 105 to 1,135 (mean 447) in seven ovaries from 

 females raised in the laboratory and from 231 to 

 563 (mean 342) for females collected off New Jer- 

 sey. The high count for females raised in the 

 laboratory may have been due to the failure of the 

 female to spawn and continued development and 

 accumulation of the eggs in the ovary because of 

 disturbances in the laboratory. There seemed to 

 be no correlation between fish size and egg num- 

 bers. The average number of eggs is less than the 

 475 to 700 eggs reported for L. atlanticus (Det- 

 wyler 1963), a larger species. 



411 



