effects of entrainment (87, 89), but there are no such studies that include 
marine fish larvae from first feeding to metamorphosis stages. 
During the past 15 years temperature responses often have been investigated 
in conjunction with effects of other environmental factors, usually variations in 
salinity for embryos and yolk-sac larvae (e.g. 66, 86). Multi-dimensional 
analysis has led to use of response surface models which permit evaluation of 
interacting effects such as between temperature, salinity, oxygen, and dose 
time (1). However, most of this research has dealt with the egg, embryo, and 
pre-feeding larval stages (e.g. 2, 3, 4, 5, 68). 
Salinity 
The developing eggs and yolk-sac larvae of many marine teleosts are known 
to tolerate wider ranges of salinity than they are likely to encounter under 
natural conditions (e.g. 2, 5, 36, 38, 68, 77, 86), but there are few studies 
dealing with salinity tolerances of typical pelagic marine fish larvae during the 
actively feeding stages. 
In unaltered environments, the effect of changes in salinity on larval survival 
may be minimal, since pelagic larvae usually will be retained within a water 
mass that does not undergo extreme salinity changes. In the lower latitudes, 
where time for larval development to metamorphosis is short, the probability 
of an extreme salinity change that might cause mortality seems even less 
probable than in higher latitudes. Holliday (36), in reviewing data on salinity 
tolerances of Atlantic herring and plaice, observed that newly hatched larvae 
had a wider tolerance range for salinity than did metamorphosed juveniles. 
Tolerance to high salinities decreased from about 60°/oo at hatching to about 
40°/oo after metamorphosis, while low salinity tolerance changed little during 
development, ranging from about 2-8°/oo for both species. Kurata (55) 
obtained similar results for Pacific herring, C. harengus pallasi larvae which 
could tolerate a salinity range of approximately 2-60°/oo at 10 days after 
hatching, but only 2-42°/oo at 20 days. 
There are several investigations on salinity tolerances of non-typical or 
non-pelagic marine fish larvae, from which conclusions about tolerances of 
marine fish larvae in general perhaps can be inferred. For mummichogs 
Fundulus heteroclitus the range of salinity tolerance was very wide, 
0.39-100.00°/oo (51). California killifish larvae F. parvipinnis also had a wide 
salinity tolerance, but the tolerance for low salinities decreased with age (76). 
Two atherinids, the California grunion Leuresthes tenuis and the Gulf grunion 
L. sardina , were tested for salinity tolerances during the larval stage (78, 79). 
Gulf grunion had a wider salinity tolerance range than did California grunion, 
but in both species the tolerance range decreased with age. A reasonable 
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