Directed Research Projects
Long-term dynamics of the Pūkorokoro wetland in response to climate change
Coastal wetlands are ground zero for the effects of climate change. They exist in a narrow band of physical and ecological factors that can be radically altered by small changes in sea level, precipitation, temperature, or storm frequency. The Pūkorokoro wetland, located near EcoQuest’s field centre on the Kaiaua coast, is one of the only active chenier plain systems in the world. It also one of the last remnants of the extensive and ecologically significant coastal wetlands that once surrounded much of the Firth of Thames. In January 2018 a major coastal inunudation (driven by a combined spring tide, storm surge, and strong onshore winds) inundated this wetland and much of the surrounding Kaiaua coast with seawater. Events such as these are predicted to become more common over the next century, and the response of the wetland ecosystem to this single event can help us understand how it will response to the pressures of climate change in the future.
In April 2018, EcoQuest established permanent transects in the wetland and carried out ecological and hydrographic surveys that record the state of the wetland in the aftermath of the inundation. These surveys were repeated in 2019, and together they form a dataset that both shows the process of recovery from a single inundation event, and forms a baseline for future surveys.
Vegetation composition and Relative abundance of native birds on Motuihe
Motuihe is one of a growing number of islands in the Hauraki Gulf that are free of mammalian predators. Vegetation surveys are carried out on a 5-year cycle. Bird surveys every two or three years. We use seven native bird species as bioindicators of changes resulting from eradication of mammalian pests and habitat restoration through planting and natural regeneration of vegetation. This work is a part of a longitudinal monitoring study that began in 2005. There are only a few small pockets of old growth forest left on the island, and bird species which rely on these habitats are largely absent. The regeneration of native vegetation is characterised by relatively rapid growth of pioneer species. Bird species respond to the changes in vegetation structure, as well the changes in abundance of (seasonal) food.