Spanish mackerel, continued 



Habitat 



Type: 



Larvae occur most frequently offshore over the inner 

 continental shelf (1 2 to 34 m) in polyhaline to euhaline 

 waters (Wollam 1 970, McEachran and Finucane 1 978). 

 Abundance appears to be greatest in the northeastern 

 Gulf of Mexico (Lukens 1989). The most frequent 

 collections of larvae are made in water depths ranging 

 5.0 to 1 2.8 m, but larvae have been found in waters as 

 deep as 91 .5 m (Dwinell and Futch 1 973, Lyczkowski- 

 Shultz 1987). 



Juveniles are found offshore and in beach surf. They 

 are sometimes reported from lower river outflows, 

 estuaries, sounds, bays, lagoons, and marshes, but 

 are generally not considered estuarine dependent 

 (Gunter 1945, Baughman 1947, Reid 1956a, Reid 

 1 956b, Zimmerman 1 969, Swingle 1 971 , Franks et al. 



1972, Christmas and Waller 1973, Dwinell and Futch 



1973, McEachran and Finucane 1978, Benson 1982, 

 Lukens 1989). They occur in oligohaline to euhaline 

 salinities, but appear to prefer euhaline water (Gunter 

 1945, Reid 1956, Franks et al. 1972, Christmas and 

 Waller 1 973, Dwinell and Futch 1 973, McEachran and 

 Finucane 1978). Most juveniles are collected from 

 waters 9.1 to 18.3 m deep, but collection depths can 

 range from the surface down to 91 .5 m (Franks et al. 

 1972, Dwinell and Futch 1973). 



Adults are typically found offshore in neritic waters and 

 along coastal areas, usually very near barrier islands 

 and particularly their passes. They frequent shallower 

 depths and are seldom found deeper than 73.2 m (Earll 

 1883, Higgins and Lord 1926, Gunter 1945, Klima 

 1 959, Springerand Woodburn 1 960, Pew 1 966, Franks 

 et al. 1 972, Christmas and Waller 1 973, Rice 1 979). In 

 Florida, most inhabit coral reefs, off-shore currents, 

 and tide rips of clear tropical waters (Klima 1 959, Moe 

 1 972). Adults are seldom taken near river mouths or in 

 low salinity waters (Earll 1883), but one study from 

 Florida reports that they enter tidal rivers on flood tides 

 to feed on shrimp migrating seaward (Tabb and Man- 

 ning 1961). One fish has also been captured in the tidal 

 portion of a south Texas river (Bryan 1 971 ). They will 

 enter estuaries and bays, especially high salinity ar- 

 eas, during seasonal migrations, but are considered 

 rare and infrequent in many Gulf estuaries (Reid 195.6a, 

 Simmons 1957, Klima 1959, Parker 1965, Pew 1966, 

 Zimmerman 1969, Powell 1975, Benson 1982). They 

 are collected from salinities ranging from oligohaline to 

 euhaline with an apparent preference for euhaline 

 waters (Gunter 1 945, Reid 1 956a, Franks et al. 1 972, 

 Christmas and Waller 1973, Dwinell and Futch 1973, 

 McEachran and Finucane 1978). 



Substrate : Juvenile mackerel seem to prefer clean 

 sand (Benson 1982), but substrate preferences for 

 other life stages of this pelagic fish have not been 

 reported. 



Physical/Chemical Characteristics : 

 Temperature: This species prefers warmer waters, 

 and generally favors water temperatures 20° C or 

 greater (Shipp 1986). Larvae are found in the north- 

 western Gulf of Mexico from 19.6° to 29.8°C, and are 

 reported to prefer ranges of 21 ° to 27°C and 20.2° to 

 29.8°C (McEachran and Finucane 1 978, Benson 1 982). 

 They have been found in Florida from 28.4° to 30.5°C 

 (Dwinell and Futch 1973). Juveniles occur over a 

 range from 10° to 34.9°C (Gunter 1945, Perret et al. 

 1971, Wang and Raney 1971, Franks et al. 1972, 

 Christmas and Waller 1973, Dwinell and Futch 1973, 

 Perret and Caillouet 1974). The occasional appear- 

 ances of juveniles in Texas bays seem to be limited to 

 waters above 24°C (Zimmerman 1969), and they are 

 most abundant in samples at 25°C or higher (Perret et 

 al. 1971). Adults have been reported occurring over a 

 range of 21 ° to 32°C and to seldom enter waters below 

 1 8°C (Earll 1 883, Gunter 1 945, Springerand Woodburn 

 1960, Fritzsche1978). 



Salinity: Salinities at larvae collection sites range from 

 28.3 to 37.4%o (Dwinell and Futch 1973, McEachran 

 and Finucane 1978, Benson 1982), and larvae are 

 most abundant at 28.3 to 34.4%o (McEachran and 

 Finucane 1 978). Juveniles can be found over a salinity 

 range of 0.21 to 37.4%o (Kelley 1965, Dugas 1970, 

 Bryan 1971, Perret et al. 1971, Swingle 1971, Wang 

 and Raney 1971, Franks et al. 1972, Christmas and 

 Waller 1973, Dwinell and Futch 1973, Perret and 

 Caillouet 1974), but occur most often in salinities 

 exceeding 10%o (Perret et al. 1971, Swingle 1971, 

 Benson 1982). Adults are generally associated with 

 marine salinities (Fritzsche 1 978), and reported salini- 

 ties range from 31.1 to 36.7% in Texas and Florida 

 (Gunter 1 945, Springer and Woodburn 1 960). 



Movements and Migrations : This species migrates 

 seasonally. Its movements are along coastlines and 

 can be extensive, depending on water temperature 

 (Powell 1975, Moe 1972, Benson 1982, Collette and 

 Nauen 1983). Three major migration routes are hy- 

 pothesized: along the Mexican-Texan coast; along the 

 northern Gulf of Mexico coast and west coast of Florida; 

 and along the Atlantic (Johnson 1 981 ). In the eastern 

 Gulf, these fish move northward in the Gulf during late 

 winter and spring appearing off the central west coast 

 of Florida about the first of April (Moe 1 972, Sutherland 

 and Fable 1 980). Movements continue westward and 

 terminate along the northern Gulf coast. During fall, 

 migration is back southward to the wintering grounds in 

 south Florida waters (Moe 1 972, Sutherland and Fable 



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