Effects of temperature and salinity on larval survival and development of the western school prawn Metapenaeus dalli

Abstract

The effects of temperature and salinity on the survival and development of larval Metapenaeus dalli were investigated in two experiments. First, the effects of four temperatures of 22.6, 25.8, 29.4 and 32.6°C on survival and development time were examined from the Nauplius VI to the Mysis I sub-stage. Survival was significantly lower at 32.6°C than at 22.6 and 25.8°C. Development times differed significantly across all temperatures, decreasing linearly with temperature from 161.5 h at 22.6°C to 74.8 h at 29.4°C then decreased slightly to 71.4 h at 32.6°C. Second, the combined effects of three temperatures (21.4, 26.5 and 29.7°C) and three salinities (30, 35 and 40%) on survival and development were quantified over a 48 h period from the Nauplius VI sub-stage. Only salinity was found to influence survival, with peak survival (77.7%) found to occur at the control salinity (*35%). Any increase or decrease in salinity from this value resulted in a decrease in survival, with the lowest salinity tested (30%) having a significantly negative effect on survival (58.4%) when compared to the control. Only temperature was found to influence the rate of development, with significant increases in development index values being recorded as temperature increased. The recommended conditions for optimal survival and development of M. dalli larvae as determined by this study are, therefore, 25.8°C and 35%.

Environmental factors influencing the reproduction of an estuarine penaeid population and implications for management

“…The spawning time of M. dalli and these fish species allows their fertilised eggs to develop in low flow conditions and be retained within the estuary (Potter et al., ; Tweedley et al., ). This time of more stable osmotic conditions may also lead to higher survival rates of penaeid larvae (Crisp, Partridge, et al., ; Preston, ).…”

“…Note that the monthly estimates of egg production assume that each gravid M. dalli recorded will spawn before the next new moon ~28 days later. This assumption was made on the basis that M. dalli of similar ovarian condition spawned within ~48 hr of transfer to an aquaculture facility, without the need for eyestalk ablation (Crisp, Partridge, D’Souza, Tweedley, & Moheimani, ; Crisp, Tweedley, D’Souza, Partridge, & Moheimani, ; Jenkins et al., ).…”

Effect of increase in temperature on the survival and growth of Macrobrachium amazonicum (Palaemonidae) in the Amazon

“…Therefore, these species are sensitive to small changes of environmental temperature. Negative impact on survival of Metapenaeus dalli at the highest temperature of 32.6°C was reported (Crisp et al, 2017).…”

“…This is one of the important factors that determine economic performance in shrimp farming (Moraes-Riodades et al, 2006;Ahmed et al, 2014;Boock et al, 2016), because the metabolic rate increases and survival with optimum temperature (García-Guerrero, 2010). Thus, for commercially cultured crustaceans, the effect of water temperatures on larval growth rates are often incorporated into planning tools, such as degree-hours or degree-days calculations (Crisp et al, 2017). Rising temperature up to certain limit favors aquaculture by reducing the time required to produce marketable sized animal and producing more generations per year.…”

“…Changes in environmental temperatures also greatly influence survival, growth, reproduction and disease susceptibility in freshwater shrimp species (Manush et al, 2004;Ahmed et al, 2014;Boock et al, 2016;Crisp et al, 2017), as this directly affects food intake and the metabolism of animals, causing stress. Survival and molting of Macrobrachium borellii and Palaemonetes argentinus were reduced at temperatures of 15 and 30°C (Montagna, 2011).…”