Bird of the Day: The Western State's Only Native Ibis, the White-faced

We are starting to keep tabs on our local bird refuges as we approach the winter season. Today was a leisurely exploration of the Merced Unit of the San Luis National Wildlife Refuge, where we were looking in on the early arrivals of species on the migratory flyway. The Ross's and Snow Geese aren't showing up yet, but there were plenty of other birds out and about, including a flock of American White Pelicans, and thousands of Sandhill Cranes. It was the White-faced Ibis (Plegadis chihi) that stole the show for me today.

The White-faced Ibis is the only Ibis found in the western United States. It closely resembles the Glossy Ibis, a species found worldwide, including Australia, Asia, Africa, South America, and Europe. The White-faced Ibis is thought to have evolved from an early incursion of the Glossy Ibis into the Americas. They were isolated in the Western United States and Central America, with a second habitat in Brazil and Bolivia. The second wave of the Glossy Ibis  occurred in the 19th century, and was initially confined to the southeastern United States. Apparently they are spreading rapidly. The territories of the two species overlap in places like Texas and Louisiana, and hybrids sometimes occur.

The individuals we saw today weren't terribly concerned about us driving by on the auto tour route (a lot of the other birds were pretty skittish). They were preening and looking for food, using their long curved beaks to probe the mud. They eat all manner of worms, salamanders, frogs, and insects.

The White-faced Ibis as a species is apparently doing okay, but was in deep trouble in the 1970s because of DDT poisoning and habitat destruction (especially the draining of wetlands; this has been particularly bad in the Great Valley). I hope to see more of them around in the future!

Bird of the Day: A Different Canada Goose, the Cackling Kind. Evolution on the Continent

If you've ever been accosted by a Canada Goose at the local park, pictures like these might give you the shivers. If one of them can deliver a nasty bite, just imagine what a few thousand of them can do. But take heart, these scenes are no nightmare. They aren't even Canada Geese. The birds occupying this field in the San Joaquin National Wildlife Refuge west of Modesto are Aleutian Cackling Geese (Branta hutchinsii). It's true, though, that before 2005 they were Canada Geese. Allow me to explain.

The Canada Goose lives in many environments, and in some cases particular flocks broke away and colonized different islands or territories (see yesterday's post for an extreme example). The presence or lack of food sources or differences in the nature of predators favored certain traits (size and behavior, for instance) in the young. The geese who summered on the Aleutian Islands were long recognized as a smaller subspecies of the Canada Goose, but recent DNA analysis has led researchers to consider these birds an entirely different species. And so these birds are not Canada Geese, they are the much smaller Aleutian Cackling Geese, which are genetically distinct from the Canada Goose.

The Cackling Geese winter by the tens of thousands in the wildlife refuge a few miles west of my home. It is a stunning sight to see so many of the birds in one place. From the observation deck on Beckwith Road, one can see and hear thousands of birds taking off and landing, and in general making a racket (cackling, as it were). They have been encouraged to stay here instead of nearby agricultural fields through the planting of corn and other food plants. In April they will pick up and leave, headed north to breed in the Arctic.

The refuge is also home to thousands of lesser Sandhill Cranes. We could just make out a flock of them in the far distance. Snow Geese also winter in the area. There were five of them among the thousands of Cackling Geese yesterday, looking mildly confused. They usually arrive in large numbers in late November or early December.

"George, are you SURE this is the right place? Shouldn't you have asked directions in Oregon?"

As we were standing and watching the flocks there was a tremendous BOOM, and thousands of the geese immediately took flight. A huge dust plume over to the west revealed where the explosion had come from. And why.

It was a huge net. Several dozen of the birds had been trapped and for the next few minutes we could see Fish and Wildlife employees tagging them.

As usual, the picture quality from YouTube sucks (the compression process I suppose), but you can get a sense of the cacophony of sound from the flying geese from the short video below.

Bird of the Day: What Happens if a Canada Goose goes on a Tropical Vacation? nene!

Perhaps 500,000 years ago, a pregnant Canada Goose, or a small flock of geese took a wrong turn. A really wrong turn. Somehow, flying along the coast of North America, the leader maybe decided to take a short cut, and it went poorly. Soon the shoreline was lost to view, and for days, not a single bit of land could be seen. I can imagine the flock becoming smaller and smaller as the weaker members fell behind and were lost.  After days of nothing but ocean, an island came into view. The tired geese landed and began looking for food. None of the plants were particularly familiar, but some proved edible and a few of the geese survived. For all we know, some of them rested up and left for further journeys, but a few stayed around. They took up residence on the volcanic island in the tropics of the Pacific Ocean, a vastly different environment than their summer home in the Canadian Arctic. The isolated volcanic edifices are today called the Hawaiian Islands.

During the millennia that followed, different flocks of geese took up residence in different ecological niches, such as lava flows, grassy slopes, and woodlands. Isolated groups began to diverge, and before long at least three species developed on the islands. One of them, the Giant Hawaiian Goose (species name not yet established), was big, almost four feet long. A lack of predators on the island made flight an energy-intensive but unneeded luxury, so the wings became smaller as the bird evolved to larger size. The goose was flightless. This worked fine for a long time, but humans ultimately arrived on the islands, and probably exterminated them, either by hunting, or by introduction of egg-eating rats, or by habitat destruction.

The second species was the nene-nui (Branta hylobadistes). It was also a big bird, but had larger wings so that it was still capable of weak flight. Like the Giant Hawaiian Goose, it became extinct soon after the arrival of humans on the islands. It has been characterized as a bird in evolutionary transition, in the midst of losing the ability to fly, but it went extinct first. Possibly because it couldn't fly well.

I didn't mean that as a flippant remark. Evolution is a process that has provided the incredible diversity on our planet, and isolated islands have provided the crucible in which much of the planet's diversity has arisen. But birds and other animals that have adapted to very specific situations are vulnerable when those situations are changed. The two extinct Hawaiian geese species were secure on the Hawaiian Islands, but the arrival of humans changed their environment too much and too fast. They were certainly easier to capture than a bird that could escape by flying.

The flying goose, the one that survived was the nene (Branta sandvicensis). The nene's wings were smaller than its Canadian ancestors, because it didn't need to migrate thousands of miles during the change of seasons. But it retained enough flying ability to escape from the island's human invaders. It differed from the Canada Goose in several other respects, including longer legs, reduced webbing between its toes, and a more erect posture. It is adapted to living on lava flows and grasslands, and was less dependent on wetlands than other geese.

It survived, but no longer thrived. Rats ate their eggs and chicks, and later on cats and mongooses were brought to the islands. The species was devastated, dropping from an estimated 25,000 when first European contact was made in 1778 to thirty individuals in 1952. A captive breeding program began, and populations were established on their ancient habitats on Maui and Kauai (where mongooses were never introduced). The wild population is now around 800, with another thousand or so in captivity. They are still highly endangered, but their prospects are slowly improving. They have been named the state bird of Hawaii.

My travels in Hawaii were part of the inspiration for my new-found love of bird watching and bird photography. I've seen the nenes (pronounced "nay-nay") on Maui at Hosner Grove (the top picture), and on the flank of Kiluaea in Hawaii Volcanoes National Park on the Big Island (the other two pictures). It is awe-inspiring to observe the descendants of a few very unlucky Canada Geese (or lucky?) who made a wrong turn 500,000 years ago and survived a terrifying journey over a very large ocean. I'm glad we're trying to help them survive, instead of driving them to extinction.

Are you interested in learning a bit more about these fascinating creatures? Here is a link for a National Geographic article on the evolution of the Hawaiian geese and their Canadian cousins, and the scholarly article of the research into the vanished species:

 http://news.nationalgeographic.com/news/2002/02/0206_020206_canadiangeese.html

 http://www.pnas.org/content/99/3/1399.full

Bird of the Day: Another Foreigner, the Eurasian Collared Dove

In the mid 1970s, the Eurasian Collared Dove (Streptopelia decaocto) was only present in the western hemisphere as a pet.  In Bermuda, the burglary of a bird shop led to the release of several doves, and for some reason the owner let the other 50 go. In the 1980s, the first Eurasian Collared Doves arrived in Florida, and now have spread across the continent, except for the Great Lakes and New England. They were in California by 2001.

I've only been at this for about a year, so I thought the doves in my neighborhood were all of the mourning kind, but I've come to realize that most of them are the Eurasian species. It's not clear if they have displaced other birds the way the European Starlings have, though. The doves are mostly taking advantage of food sources related to urban and suburban development, including feeders.

I remember the most stunning fact of birding on the Hawaiian Islands is how hard it is to actually see the native species there. The escaped pets and accidental/purposeful introductions of invasive species have simply overwhelmed the natives in the urban parts of the islands. The rapid spread of the Starlings and Collared Doves in the continental United State is concerning.

In any case the doves, if not exactly tame, are tolerant of walkers with cameras and are usually easy to photograph. I caught the first image this morning while walking in the pasture near my house. The second picture was taken in December around the same field. The birds are apparently permanent fixtures around here, despite their fairly recent arrival. And they are pretty to look at.

Bird of the Day: Raven at Happy Isles in Yosemite Valley

When the human species ceases to exist, I'm pretty sure the Ravens (Corvus corax) will take over the top spot in the world habitat pecking order. Sure, they've expanded their territory in the world by following humans, but when we go, they'll be smart enough to deal with it. I see ravens in some of the most inhospitable environments on planet Earth. In particular, they are one of the most visible birds at Death Valley National Park, the hottest and driest place in North America. They are also common in national parks across the west. The bird in today's picture was in Yosemite Valley at the Happy Isles Nature Center. I couldn't help but notice that it was hanging out next to the Hot Dog Stand.

They truly are smart. A friend of mine told me a story of a German tourist feeding some sparrows at an American Park (Yosemite, maybe?). She kept shooing off the Raven that wanted a share, so the Raven went a short distance away and waited. When the sparrow wasn't looking, the Raven swooped in...and grabbed the sparrow! The tourist was indignant...

Though mistaken for crows sometimes, the Ravens are distinctly different. They are much larger, and much less sociable, mostly hanging out in pairs. Their calls are much deeper. They range across much of the United States, in habitats ranging from alpine peaks to the hottest deserts. They are sometimes pests, but they are almost always fascinating to watch.

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...).

Bird of the Day: California's Endemic, the Yellow-billed Magpie

Today's bird is one of my favorites. The Yellow-billed Magpie (Pica nuttalli) is found only in California, mostly in the Great Valley, making it one of the few truly endemic bird species in the state. Some of the others include the Nuttall's Woodpecker (whose range includes a bit of Baja), and the Island Scrub Jay which lives only on Santa Cruz Island in Channel Islands National Park.

The Yellow-billed Magpie closely resembles the Black-billed Magpie that is widely distributed across western North America, except that it has...a yellow bill (and yellow eye-rings). The birds are genetically close, but were isolated from each other by the Sierra Nevada Mountains during the ice ages, perhaps a few hundred thousand years ago.

The birds survived a near-miss a decade ago when the West Nile Virus arrived in California. Nearly half the population was killed off in just two or three years, dropping from an estimated 180,000 individuals to only 90,000 or so. The survivors had some resistance to the virus, so the population has rebounded in recent years. It would have been a real shame to lose these beautiful and unique birds. I've enjoyed watching the flocks in my neighborhood pasture and on the west campus as well.

The last picture is not a great one (I'm working on getting a better one), but the birds in flight remind me of one of the most ancient of bird species, the Archaeopteryx. There is no close relationship, but the long tail feathers make me think of the long boney tail of the Jurassic creature that resembled the transitional species that led from dinosaur to bird (the Archaeopteryx also had teeth, a trait that only appears in bird embryos these days). I guess I'm not the only one to notice, because when I referred to the Wikipedia article on the ancient birds, they also noted the resemblance.

The Magpies on campus and in the pasture are usually pretty suspicious of me (a good trait), so I was pleased when they hung around during my walk earlier this week in the pasture near my house, and again on Tuesday when I walked the West Campus perimeter. There are several dozen individuals in each flock, which is an improvement over the last few years. It had got way too quiet when the virus was destroying the flocks. I'm glad they're back. Look to see them again soon on these pages.