Thermal Limits for Growth and Reproduction in the Desert Pupfish, Cyprinodon N. Nevadensis

摘要

The thermal limits for growth of the desert pupfish (Cyprinodon n. nevadensis) were determined in seven-week laboratory feeding experiments at three rations (1.5, 3.0 and 4.5% body weight day) of Tetra-min prepared food and seven temperatures (12, 16, 20, 24, 28, 32, and 36 C). Curves of specific growth rates (% dry weight gain/day) as related to temperature were skewed to the left at the three rations. Growth was inhibited at 12, 16 and 36 C. Fish at the lower two temperatures were torpid and lacked appetite; the higher temperature fish did not eat sufficient food to match the high metabolic cost. The thermal scope for growth was narrowed as ration decreased and as age/size increased. Taking these factors into account, the thermal limits for growth of immature pupfish feeding at moderate to high rates were 17.5 to 31.0 C with optimum growth achieved at 22.0 C. Successful reproduction depends on egg production and egg viability. (ERA citation 07:012403)