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Climate change has been the topic of much research in the last few decades, however information on its impacts — particularly on remote small island nations — remain scant. Yet, through centuries of observation of their natural environment, Pacific islanders hold a wealth of knowledge of the sky, land, and sea. Sadly, with a shift towards a more western lifestyle on some of these islands in recent decades, this local knowledge is at risk of being lost because it is not passed down to younger generations; recognizing this, Climate Change Cook Islands of the Office of the Prime Minister conducted a questionnaire survey on most of the Cook Islands from January to April 2014. The aim of the survey was to collect information on changes in various biological and physical systems over people’s lifetimes to understand climate variability in this region.

Coral atolls are natural laboratories within which to examine ecological processes (Sachet, 1967; Lee, 1984). They are often isolated, in some cases little disturbed, and have a geologically recent history of terrestrial plant colonisation. Reef islands around the rim of most atolls are Holocene in age. They are composed of biogenic skeletal sediments and have developed since reef growth caught up with sea level which stabilized after post-glacial sea-level rise. Plant colonisation of most of these islands must have occurred over a period of no more than 6000 years.

Rarotonga and Aitutaki form the summits of separate volcanic masses rising from depths of 4000 m, at which depth the cones are 45-55 km in diameter (Summerhayes and Kibblewh 1966, 1967).The lower slopes of the cones average 15-25 increasing to 30 in the upper 750 m and becoming very steep the surface reef is approached. The Mauke-Aitutaki line of islands is thought to be of early Tertiary age: the surface volcanics are much eroded, with a subdued topography, or are capped with limestones (Wood, 1967; Wood and Hay, 1970). On Rarotonga, where the relief is much stronger (maximum altitude 640 m), radiometric ages of 2.3-2.8 million years date the 1 as Pliocene (Tarling, 1967). Mangaia, with a cap of Oligoce Miocene limestones, must be much older (Marshall, 1927). Evi dence from the deep-sea drilling programme indicates that th ocean floor in the area of the southern Cooks is Paleogene (22.5-65 million years) in age (Winterer, 1973), thus provid a maximum age for the islands. It is probable that the gross history of the Cooks resembles that of other, better-known reef-capped Pacific volcanic cones known to have been initia in the early Tertiary.