First report of captive New Guinea dingo (Canis dingo hallstromi) den-digging and parental behavior.

New Guinea dingoes (NGDs) (Canis dingo hallstromi; Troughton [1957] Proc Roy Soc new South Wells 1955-1956:93-94) have been kept in zoos since 1956. Almost nothing is known of their wild behavior. These observations of a captive pair are the first documentation of natal den-digging and parental behavior for this taxon. The main den, excavated near the top of a 1.5 m hill, consisted of a rounded chamber about 50.8 cm deep, with an entrance about 30.5 cm high and 40.6 cm wide. The dam frequently moved the pups from the natal den to secondary locations for short periods during the day and then back to the den, starting when the pups were 2 weeks old. When the pups were between 5 and 12 weeks of age, both parents regularly regurgitated for them. The sire expressed escalating threat behavior toward the male pup starting when the pup was 5 months old, and the female began threatening the female pups at about 6 months of age. Rejection of same-sex offspring is usual for captive NGDs as the next breeding season approaches.