Assessing Status, Capacity, and Needs for the Ex Situ Conservation of the Hawaiian Flora

The flora of the Hawaiian Islands has one of the highest rates of endemism in the world, and over half of all taxa are at risk of endangerment or extinction. When in situ management alone cannot protect plant populations, maintaining viable germplasm using ex situ storage methods will prevent species extinctions. Germplasm collections with high conservation value are genetically diverse, representative of taxa and populations, and have a well-documented history in cultivation. Ex situ facilities and conservation agencies were surveyed to determine if existing ex situ capacity was sufficient to represent Hawai‘i’s species of conservation importance (SCI) and to identify limiting factors. SCI were defined and their representation in ex situ collections quantified, the number of wild plants and populations were estimated, and the attempted ex situ methods were recorded. There are 724 SCI, 528 of which are located in at least one facility. Sixty-four percent of the secured taxa are represented by collections from only 10% or fewer of the wild plants. Seed banks have secured more SCI, and with better in situ representation, than any other ex situ method. Seventy-eight percent of SCI have seeds with long-term storage potential. Existing seed storage facilities are currently inadequate for representing all SCI and should be expanded. SCI with low long-term potential in conventional seed storage can be represented in cryopreservation, micropropagation facilities, nurseries, and botanical gardens. Recommendations include establishing a network to coordinate collections, improve data management, and draft conservation plans with ex situ collection goals. This type of assessment can be applied to other regions that do not have a unified and consistent method of tracking ex situ representation.