Kiholo

Kiholo State Park Reserve encompasses a stunning stretch of the Big Island's Kohala-Kona coastline centered on Kiholo Bay, a turquoise lagoon renowned as one of Hawaii's premier green sea turtle viewing locations. The bay's remarkably clear, mixed fresh and saltwater creates the distinctive turquoise color that makes it instantly recognizable from the highway overlook above. The reserve protects a landscape shaped by the dramatic 1859 eruption of Mauna Loa, which sent lava flowing to the coast and destroyed a massive royal fishpond built by King Kamehameha I. Today, the partially recovered fishpond at Wainanaliʻi, the bay's volcanic shoreline, and the anchialine ponds embedded in the surrounding lava fields create a mosaic of aquatic habitats that support abundant marine life. The reserve is managed collaboratively by the state and community stewardship group Hui Aloha Kiholo.

Kiholo Bay is one of the most reliable locations in Hawaii for viewing Hawaiian green sea turtles, which congregate in large numbers to bask on the smooth pahoehoe lava rocks and feed on algae and seagrass in the shallow waters. The recovering Wainanaliʻi fishpond at the bay's northern end serves as an important feeding, resting, and nursery site for these protected reptiles, with turtles regularly seen both swimming in the lagoon and hauled out on shore and on a small island within the cove. Hawaiian monk seals occasionally rest on the bay's shoreline. The anchialine ponds in the lava behind the bay harbor endemic opaeula (Hawaiian red shrimp) found only in Hawaii's volcanic coastal groundwater systems. Reef fish inhabit the rocky nearshore waters, and spinner dolphins are sometimes spotted in the bay. During winter months, humpback whales pass through offshore waters visible from the shoreline trail.

The vegetation at Kiholo reflects the harsh conditions of a young volcanic coastline, with plant communities ranging from barren lava flows to established coastal strand. Coconut palms and other coastal trees cluster around the bay's sandy areas and the fishpond, creating patches of shade along the otherwise exposed shore. Native naupaka kahakai, beach morning glory, and coastal sedges grow along the beach margins. The surrounding lava fields support scattered kiawe trees and native pioneer species that colonize cracks and depressions in the rock. The anchialine ponds support unique algal communities adapted to the brackish, nutrient-poor conditions of volcanic groundwater pools. The marine environment includes patches of seagrass and various species of limu that provide food for green sea turtles. Restoration efforts by Hui Aloha Kiholo include planting native coastal species and removing invasive vegetation to restore the natural character of the shoreline.

Kiholo Bay's current landscape was dramatically reshaped by the 1859 eruption of Mauna Loa, which produced a lava flow that traveled approximately 30 miles from its vent near the summit to the coast at Kiholo. This eruption, which lasted approximately 300 days, sent molten rock pouring over the shoreline, destroying the massive fishpond that Kamehameha I had constructed and reshaping the bay's configuration. The resulting lava, primarily smooth pahoehoe, now forms the rocky shoreline where sea turtles bask. The distinctive turquoise color of the bay's water results from freshwater springs seeping through the porous basalt and mixing with seawater, creating a brackish layer with unique optical properties. Anchialine ponds formed in collapsed lava tubes and depressions throughout the lava field are connected to both the ocean and groundwater through the permeable volcanic rock, creating tidally influenced pools far from the visible shoreline.

Kiholo Bay benefits from the characteristically dry, sunny climate of the Big Island's leeward Kohala-Kona coast, receiving only about 10 to 15 inches of rainfall annually. The rain shadow created by Mauna Kea, Mauna Loa, and Hualalai shields the coastline from the moisture-laden trade winds that drench the island's windward side. Daytime temperatures range from the mid-70s in winter to the low 90s in summer, with the black lava fields radiating additional heat that can make hiking conditions feel even hotter. Morning hours typically offer calm, clear conditions ideal for turtle viewing and exploring the bay. Trade winds provide afternoon cooling breezes, though the leeward position means winds are generally lighter than on windward shores. The dry climate contributes to the exceptional water clarity in the bay, as minimal runoff keeps sediment levels low.

Kiholo Bay holds significant historical importance as the site of one of Kamehameha I's most ambitious aquaculture projects. In the early 19th century, after unifying the Hawaiian Islands, Kamehameha ordered the construction of a massive fishpond with walls standing 6 feet tall and 20 feet wide, enclosing a lagoon with approximately a 2-mile circumference. A village of several hundred people supported this large-scale fish-farming operation, which demonstrated the sophisticated resource management capabilities of the Hawaiian kingdom. The 1859 Mauna Loa eruption devastated this community, burying the fishpond walls under lava and forcing the abandonment of the village. The destruction of the Kiholo fishpond represents one of the most dramatic examples of volcanic impact on Hawaiian civilization. In modern times, the seven-acre site at the bay's northern end was donated to The Nature Conservancy in 2012 by the Paul Mitchell family, ensuring permanent protection.

Kiholo State Park Reserve was established to protect the bay's exceptional natural and cultural resources, including its role as critical green sea turtle habitat and the archaeological remains of Kamehameha's fishpond complex. The reserve designation reflects a management approach that prioritizes conservation while allowing compatible public access. The collaborative stewardship model, with the community group Hui Aloha Kiholo playing a central role in management alongside state agencies, reflects the Hawaiian concept of malama aina (caring for the land). The Nature Conservancy's involvement following the Paul Mitchell family's land donation added another layer of protection and resources for conservation efforts. The reserve has gained recognition as a model for community-based natural resource management in Hawaii, integrating traditional Hawaiian knowledge and practices with contemporary conservation science.

The primary access to Kiholo Bay involves a roughly 20-minute walk along a dirt road trail from the parking area south of mile marker 81 on Queen Kaahumanu Highway. The trail descends gradually through a lava field to the bay's southern end, where the turquoise waters and volcanic shoreline come into view. The Wainanaliʻi fishpond area at the bay's northern end is the best location for turtle viewing, with groups of green sea turtles frequently visible swimming in the clear water, basking on rocks, and resting on a small island within the cove. An alternative access point between mile markers 82 and 83 leads to the northern portion of the bay via a narrow gravel road. The shoreline provides opportunities for swimming, snorkeling, and wildlife observation. Exploring the anchialine ponds in the lava field behind the bay reveals the endemic Hawaiian red shrimp in these unique volcanic pools. The stunning Highway 19 overlook above the bay is a popular photo stop.

Kiholo Bay is located approximately 30 minutes north of Kailua-Kona along Queen Kaahumanu Highway (Highway 19). The primary parking area is located just south of mile marker 81, from which a dirt road trail leads approximately one mile to the bay. A secondary access point between mile markers 82 and 83 involves a narrow gravel road that is passable by most vehicles except during the final stretch, which may require four-wheel drive. There are no restroom facilities, drinking water, or food services at the bay, so visitors must come fully prepared. The walk to the bay is largely unshaded and crosses black lava, so sun protection and ample water are essential. Visitors should maintain a distance of at least 10 feet from resting sea turtles, as approaching or disturbing these federally protected animals is illegal. The bay is open during daylight hours and there is no entrance fee.

Conservation at Kiholo focuses on protecting the bay's critical green sea turtle habitat, maintaining the health of the anchialine pond ecosystem, and preserving the archaeological remnants of Kamehameha's fishpond complex. Hawaiian green sea turtles are protected under both federal and state law, and visitor education about maintaining safe distances from basking and swimming turtles is a priority for site managers. The anchialine ponds harbor endemic opaeula shrimp that are threatened by introduced fish species and changes in groundwater quality from upslope development. Hui Aloha Kiholo conducts regular monitoring, invasive species removal, and native plant restoration activities. The fishpond restoration at Wainanaliʻi represents both a conservation and cultural revitalization effort, reconnecting contemporary Hawaiian communities with traditional aquaculture practices. Climate change poses long-term threats through sea-level rise that could inundate the low-lying bay and pond habitats, and coral bleaching events that could degrade the nearshore reef ecosystem.