The World Of Jack Dempsey Cichlids

TECHNICAL INFORMATION – Jack Dempsey cichlid fish

 

Technical Information – Jack Dempsey cichlid fish

 

Salinity Tolerance:
   This species appears to have a limited salinity tolerance. Dial and Wainright (1983) reported Jack Dempsey present in waters of up to 8 ppt, and absent from contiguous waters of higher salinity in Brevard County, Florida.

Temperature Tolerance:
   The lower lethal temperature of Jack Dempsey was estimated at 8C/46F by Shafland and Pestrak (1983), upon which they placed Jacksonville as the probable northern limit for their range expansion in Florida. Jennings (1986), observed Jack Dempsey dying from cold stress, in a small creek in Alachua county, at 10-11°C

 

Reproduction and Fecundity:
   Jack Dempsey are biparental substrate spawners. Females are more active early on in development, and are highly aggressive, even towards males, when guarding the egg clutch (Zvorykin, 1995). Approximately 500-800 eggs are spawned per clutch (Riehl and Baensch, 1991; Sakurai et al., 1992). Males become more active in guarding the fry as time goes on (Zvorykin, 1995). Both male and female are extremely aggressive towards other fish (Riehl and Baensch, 1991). Jennings (1986), believed the introduced population in Alachua county, Florida spawned in Spring.

 

Trophic Interactions:
   Jack Dempsey are omnivorous. In Florida, this species has been described both as herbivorous, feeding mainly on filamentous algae (Lee et al., 1980), and as omnivorous, opportunistically feeding on insect larvae and adults, crayfish, molluscs and fish.  ♦