Land of the Lost: An Owl? In Hawai'i?

I opened this blog series on the birds of Hawai'i by discussing the nene, the Hawaiian goose species. The nene is descended from Canada Geese that ended up off course on their migrations south from Canada. It's not too surprising that they could survive the trip because the geese were strong fliers and could rest every so often. It is a great deal more surprising to see a native owl on the island. It's hard to imagine an owl surviving a journey of more than 2,000 miles over open ocean. But somewhere in fairly recent time it happened. A Short-eared Owl arrived. Accounts differ as to whether they were present when the Polynesians colonized the islands, but they were certainly present soon after. The Short-eared Owl is a common and widespread species across the planet, being found on every continent except Australia and Antarctica. The native owl in Hawai'i, the Pueo or Hawaiian Short-eared Owl, is considered a subspecies of the widespread Short-eared Owls (Asio flammeus sandwichensis). In other words, the birds have not accumulated enough evolutionary changes to be considered a separate species, although there are differences with their continental cousins. The owls are revered by the native Hawaiians, and numerous stories are told about them.

The photos above are the only clear shots I've taken of this fascinating and poorly-known bird. On a 2009 field trip with my students in Kauai, we were driving down the hill from Waimea Canyon (the "Grand Canyon of the Pacific"). I had been on the lookout for native birds all day, and had little success. As we drove by the lower end of the canyon, I was shocked to see an owl on a tree top just a short distance off the highway. I didn't know at the time that it was a rare opportunity, as they are not seen all that often, so much so that their numbers in the wild are unknown. They are considered endangered, though, because they nest on the ground and are subject to predation by mongooses, cats, dogs, and rats. They get hit by cars distressingly often, and they have been affected by the use of pesticides. Habitat loss is also a serious problem.

If you travel the islands, you may very well see another species of owl. The common Barn Owl was introduced to the islands in 1958 to help control the rodent population, especially in the sugar cane fields. As often happens in such situations, the owls made no quantifiable difference in the rat population, but instead developed a taste for some of the endangered native bird species. A controversial plan has been proposed to remove them from Hawai'i.

Bird of the Day: Pueo, the Short-eared Owl of Hawai'i

My serious interest in birds started with my travels in Hawai'i a bit more than a decade ago. The Hawaiian Islands are a marvelous laboratory for understanding the process of evolution. Few places in the world are more isolated. Bird species that make their way to the island find themselves truly isolated, with new and different food sources, different (or no) predators, and a different climate than their place of origin. Those that survive the changes in their environment gradually adapt, both in habit and in morphology. There are dozens of native species on the islands, although most of them are under siege, and many have gone extinct. The problems began with the arrival on the islands of humans along with rats. Later on, more humans came, with cats, mongooses, and mosquitoes. Avian malaria, transmitted by the mosquitoes, has done in many. People have also introduced many other bird species, as escaped pets, and as purposeful releases. The natives have been driven into marginal environments, especially the high altitude rainforests that are too cool for the mosquitoes to thrive. Few of the natives are ever seen in the cities.

On a 2009 field trip with my students in Kauai, we were driving down the hill from Waimea Canyon (the Grand Canyon of the Pacific). I had been on the lookout for native birds all day, and had little success. As we drove by the lower end of the canyon, I was shocked to see an owl on a tree top just a short way off the highway. It was a Hawaiian Short-eared Owl (Asio flammeus sandwichensis), a subspecies of Short-eared Owls found on all continents except Antarctic and Australia. Called Pueo by the native Hawaiians, the bird is revered as one of their ancestral spirits.

The owls are having a hard time of it. They nest on the ground and thus are subject to predation by the hated mongooses, rats, and cats. Mongooses were never introduced on the island of Kauai, so the owls are doing somewhat better there.

It was a thrill to see one relatively close, and willing to have a few photos taken. I hope to get back to the islands soon. I truly miss them (it's been four years...).