ʻĀhihi-Kīnaʻu Natural Area Reserve facts for kids
ʻĀhihi-Kīnaʻu Natural Area Reserve was created in 1973. It's a special place on the southwest coast of Maui, Hawaii. This reserve protects a coastal lava field and the ocean around it. It covers about 1,238 acres (501 hectares) on land and 807 acres (327 hectares) in the ocean. This area stretches along 3 miles (4.8 km) of Maui's coastline.
The reserve has many cool spots for snorkeling and diving. It also holds important cultural and geological sites. Many rare and endangered animals and plants live here. The main goal of the reserve is to protect three things: the newest lava flow on Maui, amazing coral reefs, and unique anchialine ponds.
You can find the reserve at the end of Mākena Road. It's south of Makena State Park and north of La Perouse Bay. Its exact location is 20°36′18″N 156°26′7″W / 20.60500°N 156.43528°W.
Contents
Climate and Weather
The amount of rain here changes depending on the season. Most of the rain falls during winter storms. Along the coast, about 15 inches (38 cm) of rain fall each year. Further inland, it gets about 24 inches (61 cm).
The highest point in the reserve is Kalua O Lapa, which is 520 feet (158 meters) tall. The deepest water in the reserve is 115 feet (35 meters) deep. This area gets a lot of sunshine. The dark lava rocks soak up the sun's heat. This makes the reserve warmer than the areas around it.
Geology and Land Formations
The reserve covers four traditional Hawaiian land divisions called ahupuaʻa. These divisions stretch from the mountains to the sea. They are Onau, Kanahena, Kualapa, and Kalihi. The reserve is named after the land and sea around Cape Kīnaʻu, which is at the southern end of ʻĀhihi Bay.
The reserve was designed to protect the rugged, young lava flows from the Haleakalā volcano. Much of the land is rough ʻaʻa lava. There are also some smooth pahoehoe lava flows. These flows came from the Kalua O Lapa cinder cone. They form Cape Kīnaʻu and cover the nearby ocean floor.
There are also older lava flows in the reserve, called the Kanahena flows. Scientists believe the Kalua O Lapa lava flowed between 1419 and 1621 AD. The Kanahena lava flows are even older, likely from between 1024 and 1183 AD.
Amazing Marine Life
The coral reefs in this reserve are some of the best in the main Hawaiian Islands. The reefs near Kanahena have actually grown more coral in recent years. Scientists have found at least 33 types of coral here. They also found 53 kinds of sea invertebrates and 75 types of fish. Seventeen of these fish species are found only in Hawaii.
Five protected marine animals often visit the reserve:
- The Hawaiian monk seal (Monachus schauinslandi)
- The hawksbill turtle (Eretmochelys imbricata)
- The green turtle (Chelonia mydas)
- The spinner dolphin (Stenella longirostris longirostris)
- The humpback whale (Megaptera novaeangliae)
The ocean part of the reserve is also part of the Hawaiian Islands Humpback Whale National Marine Sanctuary. The Hawaiian monk seal, hawksbill turtle, and humpback whale are all considered endangered.
Land Habitats and Plants
The Kalua O Lapa lava flow created lava tubes and dips in the ground near the coast. Some of these dips go below sea level. This allows salt water to seep in and form shallow ponds. These features create four different land habitats:
- Areas on bare lava where wind shapes the environment.
- Lava tubes and underground spaces.
- Coastal areas.
- Places where seabirds nest.
The reserve is mostly bare lava. However, there are some "kipukas." These are like green islands of plants surrounded by lava. They have native plants mixed with non-native trees. The plants here are used to very dry seasons and changing wet seasons.
Six native plant groups live here. These include naio (Myoporum sandwicense) and maʻo (Gossypium tomentosum). The wiliwili (Erythrina sandwicensis) is the main tree in the native dry forest areas. These native plants are in danger from weeds and wild animals like goats.
Twenty-one plant species and fourteen animal species are native to this area. Three plant species and five animal species are rare. One native insect, Blackburn's sphinx moth (Manduca blackburni), is endangered. The reserve is a very important home for this moth.
Anchialine Pools: Unique Water Homes
Anchialine pools are special pools of brackish water. This means they are a mix of fresh water and salt water. They get their water from underground sources, not from a surface connection to the sea. The word "anchialine" means "close to the sea" in Greek.
These pools are rare around the world. Hawaii has the only natural ones in the United States. It also has the largest number of them globally. Cape Kīnaʻu has 12 groups of these pools, including the biggest one in Hawaii.
The pools have the greatest variety of shrimp species known in the Indo-Pacific region. Five of the ten shrimp species found here are candidates for endangered species protection. These pools also provide homes for water birds, shorebirds, and birds that migrate. Native plants and algae also grow here. The endangered aeʻo or Hawaiian stilt (Himantopus mexicanus knudseni) finds food and nests in some of these pool areas.
Cultural History
The reserve holds many important historical sites. These include Hawaiian village sites from before and after Europeans arrived. There are also heiau (religious sites), burial grounds, trails, shelters, caves, and loko iʻa (fish pond) complexes. Old ranching walls and a lighthouse site are also present.
Nine site complexes are listed on the Hawaii Register of Historic Places. These include the Maonakala Village Complex and the Kualapa Cluster. Hawaii law protects all the cultural and historic sites in the reserve.
Reserve History
20th Century Changes
During World War II, the U.S. Military used south Maui for training. They built bunkers along the coast. Some of these structures can still be seen at Oneloa Beach in Mākena State Park. From 1945 to 1946, Cape Kīnaʻu was used for bombing practice by the Navy. Some old military items are still present on Cape Kīnaʻu.
The Kanahena Parking Area in the reserve was once a dump site for metal debris, like barbed wire, from the war. A popular surfing spot in the reserve gets its name, "Dumps," from this old site.
From 1980 to 2000, Maui's population grew a lot. The area near the reserve, from Kīhei to Mākena, also changed. It went from a quiet rural area to a busy tourist spot. With more people and a paved road to La Pérouse Bay in the 1990s, the reserve became very popular. In 2001, about 805 people visited the reserve each day. By 2010, even with partial closures, about 700 visitors came daily.
What is a Natural Area Reserve?
ʻĀhihi-Kīnaʻu was Hawaii's first "Natural Area Reserve." It's still the only one that protects both land and ocean resources. It's also the only place on state land where an entire lava flow, from its source to the sea, is protected.
One important rule here is a fishing ban, though it's not always perfectly followed. Walking through the reserve can be very hard because the lava is rough and uneven. This makes the reserve a great outdoor classroom. It helps people learn about the geological forces that created the Hawaiian islands.
ʻĀhihi-Kīnaʻu is one of 19 reserves in Hawaii's Natural Area Reserve System (NARS). These reserves cover over 109,651 acres (44,374 hectares). The Department of Land and Natural Resources (DLNR) manages NARS. Being a Natural Area Reserve gives the land very strong legal protection.
The NARS mission is to protect Hawaii's unique natural resources. Many reserves are far away and don't get many visitors. But coastal reserves like ʻĀhihi-Kīnaʻu are easy to reach and are used a lot by the public.
Being a reserve means you cannot remove, hurt, or kill any living thing. You also cannot damage, disturb, or remove any geological features or cultural sites.
Because of heavy use, the environment in ʻĀhihi-Kīnaʻu was starting to get damaged. Visitors sometimes got lost or hurt crossing the lava fields. Efforts to control human impact were not working well. However, a 2007 survey showed that the coral reef here was the only one in Hawaii that was not shrinking.
Advisory Group for the Reserve
An Advisory Group was created in 2002. This group gives advice about the reserve. For example, they advise on things like using kayaks or commercial activities in the area. The group includes people with different interests. These include educators, Native Hawaiians, local residents, landowners, tourists, fishers, and scientists.
The DLNR's Division of Conservation Resources Enforcement (DOCARE) helps enforce the rules. Hawaii's Historic Preservation Division also reviews any plans that might affect historic sites.
Partial Closure and Future Plans
Starting August 1, 2008, Hawaii closed access to most of the reserve. This included unofficial trails to popular spots like Kalua o Lapa and Kalaeloa ("the Aquarium"). A main reason for this closure was to protect the anchialine pools. These wetlands were threatened by non-native animals like fish or prawns, and by human activities.
The northern parts of the reserve, which are most used by the public, stayed open. These include Waiala Cove and the coast along ʻAhihi Bay, including the "Dumps" surf spot.
DLNR staff watch the reserve to see how the closure helps. The closure was originally planned to end on July 31, 2010.
After the Closure
An advisory group suggested keeping the closure going. In October 2010, the first plan for the area was released. It aimed to balance protecting the reserve with allowing human activities.
DLNR keeps monitoring the marine, geological, and cultural resources. This helps them plan for the reserve's future. The plan has taken longer than expected to finish. This is partly because ʻĀhihi-Kīnaʻu has so many cultural and archaeological sites. Budget challenges have also played a role.
Instead of fully opening the reserve, other ideas are being considered. These include guided hikes, entry permits, or special commercial tours. Guided hikes have been on hold because emergency radios and cell phones don't always work well in the area.
