For the past month, I have been looking for Kioea or Bristle-Thighed Curlew in the ponds at James Campbell National Wildlife Refuge and in the surrounding sand dunes at Kahuku.
Kioea (Numenius tahitiensis) are migratory shorebirds that live in Hawaiʻi and other tropical Pacific islands such as the Marianas, Micronesia, Fiji, Samoa, and French Polynesia for about 8 months of the year. Their most distinguishing feature is their long downward curving bills.
When I learned that kioea were in the ponds at James Campbell National Wildlife Refuge, I called the U.S. Fish and Wildlife office to attend their bird watching tours held on Thursdays and Saturdays.
The James Campbell National Wildlife Refuge covers 160 acres of wetland habitat in Kahuku at the northern most tip of Oʻahu. The refuge is located on Sand Road off Kamehameha Highway where giant windmills tower over shrimp ponds.
We were lucky to have Mike Ord lead the tour. He was well versed in the natural history of the area and the birds at the refuge. He also had a powerful scope that allowed us to see birds close up that were well over a hundred feet away.
Some of the ponds are natural but the largest ones were constructed by Kahuku Sugar Mill as settling ponds. When the mill ceased operations, the land was turned into a wildlife refuge in 1976 to provide habitat for the 4 waterfowl endemic to Hawaiʻi — aeʻo or the Hawaiian stilt, koloa maʻoli or the Hawaiian duck, alae keokeo or the Hawaiian coot, and alae ula or the Hawaiian moorhen. But many other birds benefit from the refuge as well.
We saw many aeʻo wading in the pond as we made our way to the main kiosk which is situated in the middle of several ponds with sand dunes in the background.
Click on Photo to Enlarge
The kiosk provides a 360 degree view of the freshwater ponds. Periodic maintenance is performed to optimize the habitat for waterfowl based on the season. When the breeding season is over, the grass is cut low and the reeds and rushes are removed from the ponds to keep most of the water open.
The kiosk provided a great vantage point to see the many birds at the refuge. I was thrilled when I spotted my first kioea for the season!
Kioea are rather skittish and will often run and fly away. The medium-sized bird is about 18 inches long and has a wingspan approaching 34 inches. Its beak is pink and its plumage is mostly flesh-colored to brown, with dark brown stripes on the head. The upper parts are spotted cinnamon and dark brown, the underparts are streaked buff, and the legs are a pale blue-grey.
Kioea live in Hawaiʻi and other tropical Pacific Islands for about 8 months of the year. Every April-May, the birds fly to Alaska to breed and raise their offspring. Kioea are monogamous and form lifelong pair bonds. The birds nest in the lower Yukon River and in the central Seward Peninsula of western Alaska before flying back to their tropical destinations in July-August.
Adults leave their chicks at about five weeks of age to migrate south. The chicks continue to feed until they are able to make the journey some of which require non-stop flights in excess of 2,500 miles — a feat of strength and endurance. Bristle-thighed curlew were first described scientifically during James Cook’s visits to Tahiti in the 18th century — hence the “tahitiensis” part of its latin name — but was not known to breed in Alaska until 1948. Young curlew remain in their tropical destinations for 3 seasons before flying to Alaska for their first breeding season.
When I watched the birds from the kiosk, I could see kioea flying beyond the boundaries of the refuge to the sand dunes. So I returned a week later to explore the Kahuku coastline to see if I could sneak up and get a closer look at them.
Starting from Kahuku Golf Course I made my way to the coast and then hiked to the sand dunes behind the man-made ponds where I saw a number of natural ponds ringed with naupaka. And then I saw them!
Several curlew were on the fence that separates the ponds from the grassy field and sand dunes along the coast. When I approached, one of them whistled their characteristic “kioea” call. The Hawaiians named the bird after its call.
The worldwide population of kioea is estimated at 3,500 breeding pairs. While the birds are not on the federal list of endangered species they are a threatened species. Kioea are unique among shorebirds in that they are flightless when they molt in the autumn months which makes them vulnerable to dogs, cats, mongeese, and other predators.
One of the more interesting aspects about kioea is their affinity for Molokai. Fossils indicate that the birds were found on all of the main Hawaiian Islands, but kioea were especially abundant on Molokai. Even today, flocks of kioea live on the outskirts of Kaunakakai with some individuals choosing to remain year-round.
Kioea were so important to the people and culture of Molokai that the birds are in the place names and proverbs of the island. The shoreline near Kalama‘ula homesteads is called “Ho‘olonokioea” or “listen to the kioea call” and Kiowea Park uses a spelling variation of kioea. Olelo noeau (proverbs) from Molokai include “Pa‘akea, ka la‘i o ke kioea – Kapa‘akea” or “the tranquil spot of the kioea” referring to the name of the marsh and the peacefulness of the birds and “kioea ‘ai pua ‘i‘i o Hīlia” or the “kioea that eats the fish spawn of Hïlia”.
The historic bond between kioea and Molokai was reaffirmed in 2011 when kioea was adopted as the official bird of Kaunakakai — just like how the white fairy tern or manu-o-Kū was adopted as the official bird of Honolulu in 2007.
Time passed quickly as I hid behind a mound of naupaka to watch this pair of kioea which appeared to be a mated pair. Kioea have unique personalities and are fun to watch. As I hiked back to my car, I could not help but be amazed at the great distances these fascinating shorebirds fly and how they love to kick-back and hang-out on Molokai. What amazing birds!
Bristle-thighed Curlew (Numenius tahitiensis), Kioea, Division of Forestry, Department of Land and Natural Resources, State of Hawaii
Kioea, Bristle-thighed Curlew, Declared Official Bird of Kaunakakai, Moloka‘i, ‘Elepaio, Vol 71, Number 8, December 2011, Elepaio Journal of thew Hawaii Audubon Society
Rare bird: Kauanakakai to declare special bond, The Maui News
James Campbell National Wildlife Refuge, US Fish and Wildlife
Life History of Bristle-thighed Curlews, Shorebird Research, US Geologic Service
Bristle-thighed Curlew (Numenius tahitiensis), Bird Conservation, Audubon WatchList