Some species of Acartia are known to exhibit a diapause, a resting period when the species is dormant, as a part of their life cycle. These species produce "resting eggs" when environmental conditions are unfavorable for the development and growth of nauplii. Individual females can switch between producing resting eggs and subitaneous eggs (eggs that hatch immediately) as environmental conditions change. Resting eggs accumulate in the sediment and hatch when conditions are optimal. Production of resting eggs is driven by water temperature variations. Some species (A. hudsonica) produce resting eggs when water temperatures rise above a certain threshold, while others (A. tonsa, A. califoriensis) have been observed to produce resting eggs when water temperatures fall below a certain threshold. Hatching and development of the species occur when the water cools (A. hudonica) or warms (A. tonsa, A. califoriensis). Additionally, A. califoriensis is known to be adapted to anomalous water temperature variations. Hatching is only followed by a period of steady water temperatures in the favorable range. This ensures that a generation of the species is not killed off by a momentary warming followed again by colder temperatures.
