DAHLBERG: ECOLOGICAL STUDY OF GEORGIA COASTAL FISHES 



lected at low salinities. Salinity and tempera- 

 ture ranges were 6.8 to 34.0%. and 7.0° to 32.2°C. 

 The last three cyprinodonts listed on Table 2 

 are freshwater species characteristic of the 

 Coastal Plain. The bluefin killifish {Lucania 

 goodei) is also common in fresh water on Sapelo 

 Island. 



Poecilidae - livebearers 



The euryhaline mosquitofish (Gambusia af fin- 

 is) occurred at seven habitats and was abundant 

 at the freshwater, oligohaline creek, and low-sa- 

 linity tidal pool stations. It was collected on the 

 beach only when the salinity was 6.8%o, but it 

 was not uncommon at higher salinities. Salinity 

 and temperature ranges were to 34%p and 7.3° 



to 30.7°C. 



The least killifish {Heterandria formosa) is 

 a freshwater species that occasionally wanders 

 into estuarine waters. The highest salinity rec- 

 ord was 4.0%o. 



The sailfin molly (Poecilia latipinna) was 

 common in the shallow protected waters of the 

 tidal pools, tidal ditch, and an artesian well on 

 Sapelo Island. It occasionally occurred in the 

 high marsh, beach, and oligohaline creek habi- 

 tats. Temperature and salinity ranges were 7.3° 

 to 32.2°C and to 34%t>. 



Atherinidae - silversides 



The rough silverside {Membras martinica) 

 was common at the beach and high marsh habi- 

 tats. It was attracted to artificial lights at night 

 and collected in large numbers with a dip net in 

 the lower reach. Because of their pelagic nature 

 and small size, only one was collected in a trawl. 



The Atlantic silverside (Menidia menidia) 

 was found in the four high salinity habitats and 

 in the middle and upper reaches of the estuary. 

 This silverside was common only at high salin- 

 ities, but it occurred at a sand bar in the middle 

 reach when the salinity was 0.9%. on 4 September 

 1969. Although collected at a temperature range 

 of 7.0° to 31.5°C, this silverside left the sand 

 bars of the middle and upper reaches at temper- 

 atures below 12°C, 



The tidewater silverside {Menidia beryllina) 

 was common in the freshwater and oligohaline 

 creek habitats at salinities of to 7.9%c. It 

 ranged to the middle reach when the salinity was 

 0.1%f. One was collected at Sapelo Beach when 

 the sahnity was 6.8 to 7.7%.; this was the only 

 occasion the two species of Menidia were col- 

 lected together although their habitats and sa- 

 linity tolerances overlap. 



ORDER GASTEROSTEIFORMES 



Syngnathidae - pipefishes and seahorses 



One lined seahorse {Hippocampus erectus) 

 was collected by trawl in Johnson Creek (station 

 4) in May 1969 at a salinity of 27.1%. and a tem- 

 perature of 22.3°C. The northern pipefish 

 {Syngnathus fuscus) was taken sporadically by 

 trawl and seine throughout the year. It occurred 

 in four habitats at a salinity range of to 31.3%c. 



The chain pipefish {Syngnathus louisianae) 

 was uncommon in all six habitats where it was 

 found. It was taken by trawl and seine through- 

 out the year, but was less common than the 

 northern pipefish. The chain pipefish was col- 

 lected only 12 times and at a salinity range of 

 0.7 to 31.6%o. 



ORDER PERCIFORMES 



Centropomidae - snooks 



The snook {Centropomu^ undecimalis) was 

 represented by young (23-81 mm) collected in 

 protected waters of the tidal pools and tidal 

 ditch. These were collected from June to No- 

 vember at salinity and temperature ranges of 

 to 22.1%. and 23.0° to 28.6°C. Linton and Ric- 

 kards (1965) collected 64 juveniles (24.1- 

 74.9 mm long) at Sapelo Island in 1963 and 1964. 

 Their low temperature record of 18°C occurred 

 in November. 



Serranidae - sea basses 



Of the diverse serranids found on the Georgia 

 coast, only two species range inshore to the estu- 

 ary. Young of the black sea bass {Centropristis 

 striata) and rock sea bass (C. philadelphica) 



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