Urban wetlands play key role in sustaining communities

As Oahu prepares to celebrate 2018 Worldwide Wetlands Day this week, it is fitting to look at Hawaii’s wetlands, what they do for our communities and what we can do to steward and protect these lands.

Wetlands are land areas that are saturated or flooded with water either permanently or seasonally. People often equate wetlands with wasteland — a place to be drained, burnt off and repurposed. In fact, research shows that 64 percent of the world’s wetlands have disappeared since 1900 and up to 87 percent since 1700.

In Hawaii, the estimated statewide wetland loss is 15 percent of its pre-settlement wetlands. Oahu has lost 65 percent of its wetlands, making up 55 percent of losses for all of Hawaii. The major driver of this loss has been draining for residential and urban development.

Wetlands ensure fresh water for all, enhance our food supply and purify water before it reaches the ocean protecting our coral reefs. Wetlands also help mitigate natural disasters, store carbon, are critical for biodiversity and create sustainable products.

Less than 3 percent of the world’s water is fresh, and most of that is frozen. Yet each of us requires five to 13 gallons of water a day for basic drinking, cooking and cleaning. Wetlands help to provide our water needs and replenish the groundwater aquifers that provide most of Hawaii’s fresh water.

Individual wetlands in Hawaii hold endemic species, plants and animals that are unique to the islands. These include the ‘alae ‘ula (Hawaiian gallinule), ae‘o (Hawaiian stilt) and ‘alae ke‘oke‘o (Hawaiian coot).

‘Alae ‘ula do best in protected areas where their young are safe from invasive predators, and where invasive plants are prevented from destroying their wetland habitats. These habitats are scattered widely across Oahu and support small numbers of the endangered water bird. In order to keep such isolated populations from going extinct, their habitats must be connected by the movement of the individual ‘alae ‘ula between wetlands — allowing for continuous gene flow between small populations.

Wetlands also protect Hawaii from the forces of nature, acting as a natural buffer against severe storms. Coastal wetlands are protective barriers against waves, storm surge and tsunamis. Meanwhile, inland wetlands function like sponges, absorbing and storing excess rainfall and reducing flood surges. Wetlands can speed up the recovery process following a disaster by acting as natural water filters and nutrient restorers.

By reaching out and engaging the community, we can make a lasting impact on the fate of wetland ecosystems and the endangered species that depend on them. We want to combine public participation with cutting-edge science, bringing scientists together with a passionate and active community and government collaborators to achieve high-impact and enduring conservation results.

As we look toward the future of wetlands, we must ask: What can be done to help slow, stop and reverse the trend of loss of wetlands?

Urban wetlands should be: integrated into a city’s sustainable future planning and development, included in disaster coping strategies, and adopted into policies and actions to help conserve and promote urban wetlands.

Individuals and communities can actively contribute by organizing or joining a wetland clean-up, practicing sustainable fishing, tourism and agriculture, using water more sparingly and avoiding toxic products that drain into wetlands.

This year’s World Wetlands Day, themed “Wetlands for a Sustainable Urban Future,” is the time to engage the community in the important role of wetlands for sustainable urbanization and its contribution to making cities liveable. The public is invited to attend Hawaii’s celebration this Saturday at Keawawa wetland in Hawaii Kai (see Livable Hawaii Kai Hui on Facebook for information).

Elizabeth Reilly is president of Livable Hawaii Kai Hui; Charles van Rees is an advisory ecologist for the group.