A Northern Cardinal...in Hawai'i? The Very Definition of Non-native Species

So...you're walking down a tree-lined street in St. Louis, Missouri, and you see a flash of red in the branches. It's a Northern Cardinal (Cardinalis cardinalis)! You could have the same experience walking through the desert around Phoenix, Arizona. You see them on sports monograms. It's all normal stuff if you live in such places. That's where the bird occurs naturally.

But what if you are walking through an ancient kipuka (an island of unburnt vegetation within a lava flow) on the Big Island of Hawai'i? Well, that becomes strange. What is a bird of the eastern US hardwood forests and the desert southwest doing on an island more than 2,000 miles from the mainland? In the last few posts I've been exploring some of the non-native bird species of the islands, and how they have upended the original ecosystem. The alterations and changes began more than a thousand years ago, but the rate of change increased exponentially after European colonization of the islands. New bird species were purposely brought to the islands more than 150 years ago, and they brought new diseases that the natives had no resistance to. Bird species continued to be introduced throughout the 1900s, sometimes as cage releases of pets, but sometimes on purpose. The Northern Cardinals arrived about 1928, and they spread quickly to all of the main islands, and many of the minor islands as well.

It's always a shock to see a Northern Cardinal flitting through the rainforest. The bright red color really stands out against the vegetation. I saw this individual in a tree no more than 30 feet or so from the trail I was walking through the kipuka. Kipuka Puaulu is a unique place, an ancient forest of Ohia and Koa trees that managed to miss being overrun by a fairly recent basalt flow from Mauna Loa. I recently told the story of this kipuka and one other, and to me the story is absolutely fascinating; it even includes what may be the rarest plant in the world (at least for the couple of years when none existed).

It's unclear the effect the cardinals might be having on the native birds. They spread farther and higher than some of the other introduced species. In the meantime, they are beautiful birds in a spectacular setting, even if it is far removed from the original home of the species.

Red-crested Cardinals on Oahu

In 1928 or so, the coastal towns and farmlands of Hawai'i were bereft of native bird species. Non-native species brought to the islands for a number of reasons had carried in their blood the parasite that caused avian malaria. Mosquitos transferred the disease to the native birds, and they were largely extirpated from the coastal lowlands. Most of the natives only survive above 4,000 feet where it is too cold for the mosquitos to thrive.

It wasn't that there were no birds at all in the lowlands. The Common Myna, introduced in the 1850s to control pests in the sugar cane fields, was...uh...common. There were also Spotted Doves, House Finches, and European Sparrows. But these weren't enough for some of the residents. In the 1930s, a bird club called Hui Manu devoted itself to introducing colorful and interesting birds to the islands. The effort was well-meaning, but misguided as one could imagine. Some of their introductions spread well beyond the coastal forests and spread into the higher forests where the native birds struggled to hang on. The new competition didn't help matters.

In any case, a number of the introduced birds were naturalized, and have spread widely. These are the birds most likely to be seen by tourists who stay in the coastal cities. And some of them are very colorful, literally a delight to the eye. Among them most be counted the Red-crested Cardinals (Paroaria coronata). The red head and crest seem to throw off the color balance on my camera sometimes. I saw them all over Oahu, but got the closest when we visited Waimea Valley on the North Shore, and at Kualoa Regional Park west of Kailua. Kualoa is one of the most beautiful shorelines on Oahu.

The Red-crested Cardinals rarely venture above 1,200 feet, so they probably can't be regarded as one of the "bad" invasive species that threaten the livelihood of the native species of Hawai'i. They certainly add a splash of color to the urban and developed areas of the islands.

Bird of the Day: Budgerigars in the Pastures!

This morning's walk had a big surprise. For a year I've been walking around the pasture a few blocks from my house looking for native species to photograph. I've seen 35-40 species so far, but today there was such a bright flash of fluorescent green and blue that I knew I as seeing something new.

It was immediately evident that I was not looking at a native species, because the only native parrots in the United States were extirpated nearly a century ago (the Carolina Parrot and the Thick-billed Parrot). There is a chance we may one day see the Thick-billed Parrot in the wild again, but the Carolina Parrot is gone forever. The birds in the pasture today are obviously Budgerigars (Melopsittacus undulatus), or the Common Parakeet. They are clearly escaped or released pets, because they are native to Australia.

I have no idea if this pair is naturalized or feral. It seems to me I would have noticed if they'd been around over the last year. Normally I'd be concerned about feral non-natives, but as many birders point out, these are birds that are occupying habitats made by human intervention. The native birds are already gone for the most part in the urban environment, and the parrots would disappear if we did.

In any case, the two birds I saw today provided a bright splash of color on an overcast gloomy day. I was cheered because the two were together. They are social birds, and I have a lot of empathy for any creature that is alone and separated from others of its kind.