Ocean Health Index (OHI)

The Ocean Health Index (OHI) is a scientific framework used to measure how healthy oceans are. It is the first integrated assessment framework that scientifically combines key biological, physical, economic, cultural and social elements of the ocean’s health. The OHI scores reflect how well coastal regions optimize their potential ocean benefits and services in a sustainable way relative to a target, on a scale of 0 to 100. The OHI framework integrates information from all relevant sectors into a single platform and offers various metrics to allow decision-makers to determine the appropriate balance of priorities among multiple uses to ensure that oceans can continue to sustainably deliver a range of benefits and services.

The Ocean Health Index measures the ability of oceans to sustainably provide 10 products or services (called “goals”) that are important to humans (see image below).

The global OHI was first calculated in 2013 for each country using global datasets, and has been updated annually since.

The founding partners of the Index are Conservation International, The National Geographic Society, and The New England Aquarium.


OHI+ assessments use the same framework as the global assessments, but allow for exploration of variables influencing ocean health at the smaller scales where policy and management decisions are made e.g. countries, provinces, or communities.

global OHI scores: Kenya (left) & Tanzania (right)


CORDIO East Africa in collaboration with Conservation International (CI) and national partners are implementing preliminary OHI+ assessments for both Kenya and Tanzania. CORDIO is leading the technical component of the assessments including information gathering, processing and analysis using the OHI Toolbox, as well as stakeholder engagements related to ocean governance. National partners are National Environment Management Authority (NEMA) and Kenya Marine Fisheries Research Institute (KMFRI) in Kenya and Fisheries Education Training Agency (FETA) and Tanzania Fisheries Research Institute (TAFIRI) in Tanzania.

These assessments will incorporate local information and priorities at the necessary spatial scale (national and sub-national) to build on the global assessments already undertaken for each country (Kenya, Tanzania). The process involves phases of stakeholder engagement, technical planning, data gathering, score calculation, and output dissemination to policy and decision makers.