(of an organism or tissue) living in the absence of air or free oxygen. pertaining to or caused by the absence of oxygen.
Parakeets can breed year round if conditions are right in their environment. Normal breeding season begins early in the year and continues until fall. It is very rare to see parakeets mating, but a male and a female must mate to keep the eggs fertile.
Groundhogs have to know just when to emerge from hibernation to mate so that their offspring will have the best chance of survival. âMost matings happen in a ten-day period in early March,â says Zervanos.