by the International Dark-Sky Association. This designation is given for sites in very remote locations to increase awareness of their dark sky characteristics and promote long term conservation. At the time, it was the third International Dark Sky Sanctuary to be designated, and the first island sanctuary. Population Barrier Islands statistical area, which includes Little Barrier Island and Mokohinau Islands although they have no permanent inhabitants, covers and had an estimated population of as of with a population density of people per km2. Barrier Islands had a population of 930 at the 2018 New Zealand census, a decrease of 3 people (−0.3%) since the 2013 census, and an increase of 63 people (7.3%) since the 2006 census. There were 531 households, comprising 501 males and 429 females, giving a sex ratio of 1.17 males per female. The median age was 52.6 years (compared with 37.4 years nationally), with 138 people (14.8%) aged under 15 years, 90 (9.7%) aged 15 to 29, 477 (51.3%) aged 30 to 64, and 225 (24.2%) aged 65 or older. Ethnicities were 91.3% European/Pākehā, 20.6% Māori, 2.6% Pacific peoples, 1.3% Asian, and 1.9% other ethnicities. Percentages may add up to more than 100% as people may identify with more than one ethnicity. The percentage of people born overseas was 18.4, compared with 27.1% nationally. Although some people chose not to answer the census's question about religious affiliation, 62.6% had no religion, 24.5% were Christian, 1.3% had Māori religious beliefs, 1.0% were Buddhist and 1.6% had other religions. Of those at least 15 years old, 144 (18.2%) people had a bachelor's or higher degree, and 144 (18.2%) people had no formal qualifications. The median income was $21,300, compared with $31,800 nationally. 48 people (6.1%) earned over $70,000 compared to 17.2% nationally. The employment status of those at least 15 was that 279 (35.2%) people were employed full-time, 168 (21.2%) were part-time, and 57 (7.2%) were unemployed. Settlements The population lives mostly in coastal settlements. Tryphena, in Tryphena Harbour at the southern end, is the largest settlement. Other communities are Okupu and Whangaparapara in the south-west, Port Fitzroy and Okiwi in the north, and Claris and Medlands in the south-east. The population swells substantially from October to May. The island has become a favourite holiday destination in the darker months, due its superbly dark sky and the astrophotography and stargazing opportunities this offers. In 2017 the island was