The Secretariat of the Pacific Community estimates the region's population is growing by about the size of Samoa every year.
It says the regional population will reach nine and a half million this year, 180 thousand more than last year.
The SPC says the population of Papua New Guinea will reach nearly six and a half million this year, taking the total throughout Melanesia to eight million 300 thousand.
It says the average growth across the Pacific is one point nine percent, with the fastest growing, Guam at 2 point eight percent, Solomon Islands at two point seven and Vanuatu at two point six.
It also notes continuing population decline on Niue falling two point four percent due to continuous migration to New Zealand, and the Northern Marianas down one point seven, due to the closure of many garment factories.