▁those ▁of ▁territorial ▁authorities ▁( second ▁tier ). ▁Regional ▁authorities ▁are ▁primarily ▁responsible ▁for ▁environmental ▁resource ▁management , ▁land ▁management , ▁regional ▁transport , ▁and ▁bio security ▁and ▁p est ▁management . ▁Territ orial ▁authorities ▁admin ister ▁local ▁road ing ▁and ▁res erves , ▁waste ▁management , ▁building ▁cons ents , ▁the ▁land ▁use ▁and ▁sub div ision ▁aspects ▁of ▁resource ▁management , ▁and ▁other ▁local ▁matters . ▁ ▁The ▁Ch ath am ▁Islands ▁is ▁not ▁a ▁region , ▁although ▁its ▁council ▁oper ates ▁as ▁a ▁region ▁under ▁the ▁Resource ▁Management ▁Act . ▁There ▁are ▁a ▁number ▁of ▁out lying ▁islands ▁that ▁are ▁not ▁included ▁within ▁regional ▁boundaries . ▁The ▁Ker made cs ▁and ▁the ▁sub ant ar ctic ▁islands ▁are ▁inhab ited ▁only ▁by ▁a ▁small ▁number ▁of ▁Department ▁of ▁Conserv ation ▁staff . ▁ ▁Population ▁ge ography ▁ ▁The ▁South ▁Island ▁contains ▁a ▁little ▁under ▁one - qu arter ▁of ▁the ▁population . ▁Over ▁three - quarters ▁of ▁New ▁Zealand ' s ▁population ▁live ▁in ▁the ▁North ▁Island , ▁with ▁one - third ▁of ▁the ▁total ▁population ▁living ▁in ▁the ▁A uck land ▁Region . ▁A uck land ▁is ▁also ▁the ▁fast est ▁growing ▁region , ▁account ing ▁for ▁ 4 6   percent ▁of ▁New ▁Zealand ' s ▁total ▁population ▁growth . ▁The ▁majority ▁of ▁the ▁ind igen ous ▁M ā ori ▁people ▁live ▁in ▁the ▁North ▁Island ▁( 8 7   percent ), ▁although ▁a ▁little ▁under ▁a ▁quarter ▁( 2 4   percent ) ▁live ▁in ▁A uck