Almost nothing is known about the behaviour of Newton's parakeet, but it is probable that it was similar to that of other members of its genus. Leguat mentioned that the parrots of the island ate the nuts of the bois d'olive tree ("Cassine orientalis"). Tafforet also stated that the parrots ate the seeds of the bois de buis shrub ("Fernelia buxifolia"), which is endangered today, but was common all over Rodrigues and nearby islets during his visit. Newton's parakeet may have fed on leaves as the related echo parakeet does. The fact that it survived long after Rodrigues had been heavily deforested shows that its ecology was less vulnerable than that of, for example, the Rodrigues parrot.