Enhancing populations of loulu and kokio keokeo in the upper limahuli preserve – project will establish genetically diverse populations of hibiscus waimeae subsp

The National Tropical Botanical Garden (NTBG) received a $100,999 Cooperative Agreement from the U.S. Fish and Wildlife Service under the Partners for Fish and Wildlife Program (CFDA 15.631), effective October 1, 2025 through September 30, 2027. The project focuses on enhancing populations of two endangered Hawaiian plant species—Hibiscus waimeae subspecies hannerae and Pritchardia napaliensis—within the 400-acre Upper Limahuli Preserve ungulate exclusion fenced area. NTBG will propagate and outplant 75 individuals of H. waimeae subspecies hannerae and 100 individuals of P. napaliensis using genetically diverse specimens from its conservation seed bank and living collection. Both species face critical survival threats; approximately 200 adult H. waimeae subspecies hannerae individuals remain in the wild with minimal regeneration, while P. napaliensis has fewer than 90 wild individuals remaining.

The project delivers comprehensive habitat restoration and species protection services including propagation of seedlings in NTBG's conservation nursery, installation of predator management infrastructure (Goodnature traps for rat control and baiting protocols for slug and snail management), and monitoring systems for invasive coconut rhinoceros beetle threats. NTBG will implement an integrated pest management plan adapted from its South Shore Gardens operations to protect the outplanted populations. These coordinated conservation activities support the Partners for Fish and Wildlife Program's mandate to restore habitat and conserve federal trust species through cost-effective, partnership-based initiatives benefiting endangered flora in Hawaii.

Hannerae (e) and pritchardia napaliensis (e) within the 400-acre ungulate exclusion fenced area. Approximately 200 adult individuals of h. Waimeae subsp. Hannerae remain in the wild in three valleys, with little or no regeneration observed. The latest USFWS 5-year review of the taxon recommended establishing new, genetically diverse populations and managing the threats of ungulates and rats. Ntbg has already made strategic crosses between a mother plant from limahuli lower preserve and a father from pohakuao. The seeds of these crosses are currently stored in ntbgs conservation seed bank. Plants will be propagated in our conservation nursery using seeds from our seed bank as well as through cuttings from individuals collected from throughout the native range in northwest kauai that are present in ntbgs living collection. Pritchardia napaliensis has fewer than 90 individuals remaining in the wild. These plants are similarly threatened by seed predation from rats and ungulates, as well as habitat degradation and the new threat of coconut rhinoceros beetle. CRB monitoring traps in lower limahuli valley will be checked regularly. If CRB is detected in the valley, the integrated pest management plan for CRB that was recently developed and currently being implemented for ntbgs south shore gardens will be adapted for and implemented in limahuli. Ntbg currently has 477 seedlings of p. Napaliensis from wild collected seeds growing in our nursery. We propose to enhance and expand the ULP populations of both taxa by planting 75 individuals of h. Waimeae subsp. Hannerae and 100 individuals of p. Napaliensis into an area of the ULP that will be managed and protected from several key predators. All outplants will be protected from rats via goodnature traps and from slugs and snails by baiting the area upon outplanting. Signs of slug and snail damage will be monitored every six months and bait RE-applied as needed.