year, rather than the annual averages are used. 

 Neither the data presented in this paper nor other 

 available pertinent data have been statistically 

 processed. Therefore we have limited ourselves 

 to seek only most general patterns based on the 

 most obvious dramatic changes and to point out 

 apparent or likely correlations. 



THE RED SEA LIZARDFISH 

 The Invasion 



Prior to 1954, two species of lizardfish (Synodon- 

 tidae) occurred rather infrequently in the catches 

 of the Israeli Mediterranean trawlers: Synodus 

 saurus (Linnaeus), a tropical Atlantic and 

 Mediterranean species (Fowler, 1936), and the 

 Red Sea lizardfish, an Indo-Pacific species. The 

 latter was first reported from the Mediterranean 

 as Saurida grandisquamis (Gunther) by Ben- 

 Tuvia (1953, in press), who found it for the first 

 time in December 1952. At that time, neither 

 species was of commercial value, and S. undo- 

 squamis was much rarer than Synodus saurus 

 (Ben-Tuvia, 1953, in press; Oren, 1957). 



Ben-Tuvia (in press) observed that as early as 

 August 1953 the lizardfish was fairly common in 

 trawl catches taken in the Gaza-El Arish area, 

 with 10 to 20 specimens caught usually in each 

 haul. 



In the winter of 1954-55, together with other 

 changes in the composition of trawl catches, the 

 proportion of the Red Sea lizardfish increased to 

 such an extent that the fishermen attempted to 

 market them as a food fish (Ben-Yami, 1955). Con- 

 sequently, in 1955 lizardfish appeared for the first 

 time in the statistics of landings (Sarid, 1956). 



In the summer of 1955, unusual numbers of 

 fingerlings were found in the cod ends of trawl 

 nets. The bulk of them consisted of two Red Sea 

 species, the yellow-striped goatfish and the 

 lizardfish (Ben-Yami, 1955). 



In 1955-56, the lizardfish became one of the 

 main commercial fishes in Israel; its proportion in 

 the total landings of Israel's marine fishery 

 reached 11% (Sarid, 1956), and in the trawl fishery 

 landings approximated 20% (Figure 5). Catch 

 data collected during 1955 and 1956 (Oren, 1957) 

 indicate that the Red Sea lizardfish made its first 

 significant appearance in the trawl catches in the 

 fishing grounds off the Gaza Strip and North 

 Sinai. By the end of summer and autumn of 1955 



FISHERY BULLETIN; VOL. 72, NO. 2 



it had expanded all over Israel's fishing grounds. 



During the period 1952-60, most Israeli trawl- 

 ers fished in the summer months in the north- 

 eastern part of the Mediterranean (Gulf of Tarsus 

 and neighboring waters). The Red Sea lizardfish, 

 however, was not found in those waters in 1952 by 

 Gottlieb and Ben-Tuvia (1953), who produced a 

 detailed list of 52 fish species caught in a trawl 

 catch. By summer 1956, it was common in the 

 trawl catches in the Bay of Tarsus (Ben-Tuvia, 

 pers. comm.), and since then it has become well 

 established and is one of the most important com- 

 mercial fish in that area. 



The quantity of lizardfish caught by the trawl- 

 ers continued to increase until 1959 when almost 

 400 tons (20% of the total trawl catch) were landed 

 (Sarid, 1960). This was followed by a 4-yr reces- 

 sion. In 1963, the catches dropped to an approxi- 

 mately 120-ton low, and since then, they appar- 

 ently stabilized near this level with "normal" an- 

 nual fluctuations. 



Food and Habitat 

 of the Red Sea Lizardfish 



The lizardfish is a demersal piscivore. Its food in 

 the Levant Basin was studied by Bograd- 

 Zismann (1965) and by Chervinsky (1959). 

 Bograd-Zismann examined some 1,500 stom- 

 achs, of which 859 contained food. Of these, 

 77.3% contained fish; the rest contained inverte- 

 brates, mostly crustaceans, and digested matter. 

 Chervinsky examined some 500 stomachs, of 

 which 131 contained identifiable food. Large in- 

 vertebrates were found in only 16 stomachs; the 

 rest contained fish. Both authors indicate that the 

 most frequent prey of the Red Sea lizardfish are 

 clupeoid fish-according to Chervinsky (1959) an- 

 chovy, and according to Bograd-Zismann (pers. 

 comm.) mostly anchovy, but also some sardines. 



The second important group in the food of the 

 lizardfish are fish of the family Mullidae 

 (Bograd-Zismann, 1965; Chervinsky, 1959). 

 Other important groups in the lizardfish food are 

 Gobiidae, Centracanthidae (listed as Maenidae 

 by Bograd-Zismann, 1965, and by Chervinsky, 

 1959), and Leiognathus klunzingeri (Stein- 

 dachner) (Bograd-Zismann, 1965; Chervinsky, 

 1959; Ben-Tuvia, 1966). 



No direct information is available on the 

 diurnal-nocturnal feeding activity of the i 

 lizardfish in the Levant Basin. Nonetheless, the 

 high proportion of anchovy in the food of the ' 



364 



