(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.
Hummingbird Breeding. Mating is a very interesting time to observe the behaviors of the Hummingbird. Most species are mature when they are just a few months old. They typically have breeding grounds that they return to year after year. The season for breeding varies based on the climate in that given region.