What are mangroves worth? There’s no easy answer
Our existence depends on flows of goods and services delivered by a stock of natural resources – our ‘natural’ capital. But as we have degraded the planet’s ecosystems, we’ve lost huge stocks of this natural capital and we are starting to feel the pinch.
Photo: Bob Fisher/IUCN
People have long depended on natural systems for our survival and development, nowhere more visible than in our history of extracting minerals and fuel products. However, we have also started to see the importance of healthy ecosystems for providing essential goods and services, especially as these stocks of natural capital disappear.
In response, action is being taken to restore and protect ecosystems, including global efforts aimed at estimating the economic value of the Earth’s natural capital – in hard numbers. Knowing the economic worth of ecosystem services can help ensure that those who rely heavily on ecosystems – from governments to industries and businesses to all of us as citizens – see their value and can account for restoration and conservation in their planning and use.
Mangrove ecosystems in particular provide a multitude of goods and services, including: provision of food and clean water (provisioning services), influence climate regulation, soil composition regulation and disaster risk reduction (regulating services), and recreational and spiritual space (cultural services). The natural capital of mangroves thus has immense worth not only in sustaining lives and livelihoods of millions of people along the world’s coasts, but also in real economic terms.
Determining this value, however, is tricky and depends on the type of goods and services considered as well as the method of valuation. Their value is strongly context-dependent (space, time, land use, and land management) as well as scale-dependant. Here are some things to keep in mind when thinking about the value of mangroves:
1. Mangroves’ value can be reflected in the market price of what is produced
Provisional services represent tangible goods people use for multiple purposes. They are usually valuated by the market and priced according to specific markets. For instance, mangrove fisheries and forestry products are prominent mangrove resources for which market values are readily estimated. The market price includes the value of nature contribution, costs of fishing, collecting, or harvesting, as well as earnings. When goods are not bought or sold on the market (e.g. timber collected for firewood, or seafood or honey used for subsistence purposes), the value can be inferred from other market values or the cost of replacing what nature provides with a nearest substitute.
2. Mangroves’ value as incentive for the tourism sector
Mangroves offer great opportunities for wildlife viewing and other recreational activities such as fishing and diving. They also often grow in close proximity to other tourist attractions such as coral reefs and sandy beaches. Therefore revenues from tourism-related spending can provide special incentives for restoration and conservation of mangroves as pristine habitats. The current rise in tourist demand for sustainable options (ecotourism) could provide stakeholders with good opportunities for capitalising on intact and species-rich mangrove ecosystems.
3. Mangroves’ value often isn’t appreciated until they are gone
Mangroves function as a natural infrastructure for resilient coasts, especially by reducing storm surge and waves. These benefits are often felt most acutely once mangroves have disappeared – either when property owners attempt to replace these lost services with breakwaters and seawalls or when property and lives are lost because of flooding and storm damage. Both can result in large out-of-pocket costs. In fact, protecting and restoring whole mangrove ecosystems has shown to be less costly than paying for the building and maintenance of artificial storm protection.
4. Mangroves’ value is understood by the insurance sector
The role that mangroves play in protecting property is increasingly understood by the insurance industry. If insurers lower premiums to reflect the cost-savings provided by healthy mangrove forests, then insured property owners will have an incentive to protect mangroves and insurers can avoid some of the large payouts that result from cyclones and other wave events.
5. Mangroves’ value is increasingly reflected in the carbon market
Due to their ability to sequester and store carbon, mangroves are increasingly in the focus of climate mitigation actions. Conservation projects that restore and protect mangrove forests (such as Mikoko Pamoja in Kenya) have used new methodologies to measure the carbon content in these systems, and to receive payments through the accredited sale of carbon credits (unit of sequestered carbon per tonne).
There are different methods of estimating the economic value of mangrove ecosystems which may serve to demonstrate the significant potential of wealth increase with the conservation of natural mangrove capital. However, few estimates of value can adequately capture the entire value of mangrove forests. The grand total of benefits derived from mangroves is likely greater than what is reflected in the estimated values of its parts. It is ultimately up to the stakeholders and decision makers to treat these numbers as illustrative and to proceed with caution in order to make informed and ethically responsible decisions.
This article series on mangrove restoration is written by Juliet Blum and Dorothée Herr from IUCN's Global Marine and Polar Programme with the support of Germany's International Climate Initiative (IKI) through the IUCN Global Forest and Climate Change Programme. Philippe Puydarrieux (IUCN Science & Knowledge Unit) and Gerard Bos (IUCN Global Business and Biodiversity Programme) contributed to this article.