Human-forced climate change significantly threatens the world’s freshwater ecosystems, through projected changes
to rainfall, temperature and sea level. We examined the threats and adaptation opportunities to climate change in a
diverse selection of rivers and wetlands from Oceania (Australia, New Zealand and Pacific Islands). We found common
themes, but also important regional differences. In regulated floodplain rivers in dry regions (i.e. Australia), reduced
flooding projected with climate change is a veneer on current losses, but impacts ramp up by 2070. Increasing drought
threatens biota as the time between floods extends. Current measures addressing water allocations and dam
management can be extended to adapt to climate change, with water buy-back and environmental flows critical.
Freshwater wetlands along coastal Oceania are threatened by elevated salinity as sea level rises, potentially mitigated
by levee banks. In mountainous regions of New Zealand, the biodiversity of largely pristine glacial and snow melt
rivers is threatened by temperature increases, particularly endemic species. Australian snow melt rivers face similar
problems, compounding impacts of hydro-electric schemes. Translocation of species and control of invasive species
are the main adaptations. Changes to flow regime and rising water temperatures and sea levels are the main threats
of climate change on freshwater ecosystems. Besides lowering emissions, reducing impacts of water consumption
and protecting or restoring connectivity and refugia are key adaptations for conservation of freshwater ecosystems.
Despite these clear imperatives, policy and management has been slow to respond, even in developed regions with
significant resources to tackle such complex issues.
Climate change and freshwater ecosystems in Oceania: an assessment of vulnerability and adaptation opportunities.
