The domestic rabbit (Oryctolagus cuniculus) is a burrowing rabbit native mainly to the Iberian Peninsula that digs networks of underground tunnels (warrens) to create living spaces and nests. It has a body length of about 34–50 cm and a body mass of 1–2.5 kg and is herbivorous; it obtains nutrients by reingesting soft feces that have been fermented in the cecum. It is nocturnal to crepuscular and typically lives in small groups. Breeding can occur year-round, gestation lasts about one month, and it usually gives birth to 3–6 hairless young. Wild populations have declined due to infectious diseases and habitat destruction, and the species is classified as Endangered B1 by the IUCN. Conversely, in areas where it has been introduced its high reproductive rate can become problematic and it is sometimes treated as an invasive alien species.