BEN-YAMI and GLASER: INVASION OF SAURIDA UNDOSQUAMIS 



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52/53 54/55 56/57 58/59 60/61 



62/63 64/65 66/67 68/69 70/71 



YEAR 



Figure 5. — Changes in the hake — Red Sea lizardfish relationship in catches and the catch-per-unit-effort (cpu) in 

 the Israel trawl fishery in the Mediterranean, 1950-70 (Sarid, 1951-71). A - cpu— all fish, each year starts 1 

 January; B - cpu — (1) lizardfish, (2) hake; C - proportion in catch, percent: (1) lizardfish, (2) hake. BandC — each 

 year starts 1 September. 



lizardfish may indicate that either the lizardfish is 

 a demersal feeder, feeding on clupeoids only when 

 it approaches the bottom of the sea during the 

 hours of light, or that it ascends during the night 

 to the upper water layers where it could feed on 

 these pelagic fish. We favor the first hypothesis, 

 for the lizardfish almost never occurs in the night 

 catches of purse seines in light fishing. This 

 hypothesis is corroborated by observations of 

 Hiatt and Strasburg (1960) of two lizardfishes, 

 Saurida gracilis and Synodus variegatus, of the 

 Marshall Islands. The lizardfish lie motionless, 

 on or partly buried in the sand, and are virtu- 

 ally impossible to detect. Only when small fish 

 come within a distance of a few feet, the lizardfish 

 seize them in a rapid dart. They were rarely ob- 



served to ascend for more than 3 to 4 feet while 

 attacking their prey. 



Hayashi, Yamaguchi, and Hanaoka (1960) and 

 Toriyama (1958) reported on the basis of stomach 

 examinations that S. undosquamis in Japanese 

 waters feeds during most hours of day and night. 

 According to Toriyama, however, feeding activity 

 is most intensive during the early morning hours. 



According to Chervinsky (1959), the lizardfish 

 is cannibalistic. Bograd-Zismann (1961-62) ob- 

 served that the occurrence of lizardfish in 

 stomachs may rather be a result of panicky indis- 

 criminate attacking in the trawl cod end. 



The Red Sea lizardfish in the Levant Basin pre- 

 fers rather shallow waters. It is caught in the cool- 

 er seasons at depths generally not exceeding 45 fm 



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