with that of the pink pigeon (Nesoenas mayeri), the Mauritius bulbul (Hypsipetes olivaceus), and the Mauritian flying fox (Pteropus niger). The echo parakeet is only territorial during the breeding season and defends the area around the nest tree. Their territoriality is inconsistent and not vigorous, and birds are in loose association with their breeding areas outside the season. They may direct their territorial aggression at both conspecifics and other species, many encounters being subtle and hard to recognise. Both sexes take part in defence before laying, but the male takes a dominant role afterwards. They first react by calling, which may be enough to discourage an intruder, but if the interaction becomes more intense, one or both members of the pair will approach the intruder by cautiously jumping between tree limbs, and will circle slowly around the trees near the nest, as the intruder gets closer. Fights are rare, although on one occasion two males were observed fighting in low bushes and then on the ground; one male broke free and flew away, and neither appeared to be seriously injured. The rose-ringed parakeet (of the subspecies P. k. borealis) was introduced to Mauritius around 1886 and is now flourishing there. Its population is estimated at 10,000 birds and it is widespread across Mauritius. Closely related to the echo parakeet and physically similar, though no hybrids have been recorded, they compete for nest-sites and probably some food, but are usually passive towards each other outside the breeding season; they have been seen pursuing each other as well as flying together and feeding in the same trees. While the rose-ringed parakeet has much broader feeding requirements (and may be ecologically separated), it may have excluded the echo parakeet from expanding and adjusting its feeding ecology to the changing environment by entirely occupying this more generalised niche. The most serious form of competition between the echo parakeet and the rose-ringed parakeet is over nest-sites; the introduced species often takes over cavities used by the native parakeets. Echo parakeets are reportedly easily frustrated when defending their nest-territories and have been seen relinquishing them without physically defending them. Two out of seven echo parakeet nest cavities were taken over by rose-ringed parakeets in 1974, and only rose-ringed parakeets were nesting in the Macabé Ridge area for several years. Status Decline There are believed to have been seven endemic Mascarene parrot species; all but the echo