Saturday, October 27, 2012

Ducks!

Yes, I live in a desert, and no, we don’t have a coastline here in southern AZ. But we are fairly close to the Gulf of California, and we get a lot of shore birds passing through and/or spending the winter right here in Tucson and in other parts of southern Arizona.

If you like ducks (and who doesn’t?) there are a number of places in the Tucson area where you can see them.        

Ducks in Reid Park, Tucson, Arizona

Sweetwater Wetlands, a sewage treatment plant fairly near my home,  does not smell sweet but harbors water birds all year round, and particularly in the cool/cold months. Water birds also frequent Aqua Caliente Park, a beautiful nature preserve in the far eastern part of Tucson, that is fed by natural warm springs. The city of Tucson itself is graced with a number of large city parks with ponds and artificial waterfalls and fountains.

I visited one of these parks, Reid Park, twice in the last ten days. Reid Park, which also has a zoo and a golf course, is in the center of town. Its two large ponds not only attract ducks, they also draw migrating and overwintering waterfowl of many different sorts. Last week, for example, I saw a cormorant, a great blue heron, and a seagull! The park itself is grassy and dominated by large evergreen, palm, and eucalyptus trees, which many of the waterfowl seem happy to perch in.

Here are some of the beautiful birds I saw on my recent visits:

Great Egret neck 10-16-2012 9-26-32 AM 1021x2681                 Great Egret best 10-16-2012 9-26-43 AM 2821x2588

These photos are of a Great Egret that was visiting the pond. I watched it swallow a fairly large fish, which you could follow down that long, slender neck. It’s a gorgeous bird that seems to like to roost in a eucalyptus tree.

Ring-necked duck best 10-25-2012 9-13-58 AM 1608x1158                 Coot 10-25-2012 9-04-23 AM 928x1384

These are two of my favorite ducks, the ring-necked duck on the left, which I like because it is beautiful and because it has a prominent ring on its bill (a much fainter one on its neck); and the coot, which is beautiful shiny black and has blue feet with weird-looking toes, padded for walking on marshy ground. The first time I saw a coot’s feet, I thought they looked like blue crayfish.

Finally, I saw a large, gorgeous bird I had never seen before, a black-crowned night heron, which posed both in a tree and beside the pond:

Black-crowned night heron in tree 10-25-2012 9-10-43 AM 1939x2487             black-crowned night heron on ground 10-25-2012 9-14-57 AM 2403x2257

Friday, October 19, 2012

Mid-October Birding at Tohono Chul Park

Today was a terrific day for a bird walk in the Park: clear blue skies and temps in the low seventies. I was greeted almost as soon as I arrived by white-crowned sparrows, which I had not seen since early spring.

white-crowned's crown 12-20-2010 9-41-10 AM 732x591

In the front of the Park, a rare treat: a cactus wren building a nest in the saguaro at the top of the trail that enters the Park!

                      Saguaro with nest at TCP 10-19-2012 8-49-26 AM 2299x2421

Cactus wrens build messy, football-shaped enclosed nests throughout the year. Nobody knows why they build multiple nests—possibly some of them are decoys. It’s not unusual in any given month to see a cactus wren with nesting material in its beak.

Cactus Wren Building Nest in Saguaro

  This wren repeatedly selected material from either side of the path, flew up into the cactus, added the new nesting materials, arranged them carefully, then flew back to the ground to repeat the process. Here is a brief video showing the bird’s efforts.

Cactus wren building nest in saguaro at Tohono Chul Park, Tucson AZ

Sunday, October 14, 2012

Why do hummingbirds fight?

“Cool it, guys! There’s plenty for everybody!”

Yes, I do talk to my birds, and often exhort the hummers to play nice with one another and stop fighting over the feeders. These fierce little jewels always ignore my advice. I recently read a discussion on a hummingbird mailing list that goes a long way toward explaining this aspect of hum-behavior.

According to Lanny Chambers, a hummingbird expert whose excellent website, Hummingbirds.net, is packed with photos and information on hummingbirds, hummers fight because:

 Anna flying

…they treat feeders essentially the same as flowers. A good patch of wildflowers in the middle of nowhere will provoke chases and battles, as one bird tries to defend the territory against all intruders. So, the real question is, "why are hummingbirds so territorial?"

The answer for adult males in spring is easy: the birds with the best territories attract the most females, and get the most sex. Hens want strong genes for their chicks, and they know where to find them: the nastiest, meanest, most evil-tempered studs will be successfully holding down the most desirable food resources.

Outside of that scenario, each flower contains a tiny amount of nectar, replenished slowly over time. A hummer doesn't want another bird to get the nectar first, since it will have to wait until the flower produces more, so the resource is jealously guarded. I don't think a hummingbird has any concept of unlimited supply, so they defend feeders for the same reason.

There are some occasions on which hummingbirds will share food. I myself have observed this, most often at the end of the day or during a cold snap. A couple of years ago two young male Costa’s hummingbirds uneasily co-guarded my patio feeder, as I described here. But this behavior is very rare.

Costas2 5-25-2011 5-01-54 PM 2447x1044

Nancy L. Newfield of Louisiana, author and hummingbird expert, believes the hummingbirds’ perception of the rarity of nectar is “the crux of the whole matter.Every drop of nectar is regarded as the last drop of food on Earth.  They defend their food source because their very life depends on food.” 

Adds Sheri L. Williamson, another expert, who is author of the indispensable Peterson’s Field Guide to Hummingbirds of North America, “It’s all about that limited resource and walking (well, hovering) a very fine line between survival and starvation.”

Sunday, October 07, 2012

Butterfly Sex Notes

Birds do it, bees do it, and butterflies do too. Early fall is butterfly heaven in Tucson, and Tohono Chul Park is jam-packed with many beautiful species of butterflies. 

Here are some beautiful queen butterflies, sampling the delights of ageratum:

             butterflies and ageratum2 great 9-7-2010 8-53-49 AM 3616x2712

The butterflies are males (as evidenced by the black-enclosed white dot on their hindwings), and they are imbibing an alkaloid that will help them produce a pheromone that some references say “aids in mating.” My butterfly app says that the pheromone enables them to “subdue the female,” so you might think of it as a butterfly date drug.

These pipevine swallowtails were caught mating in the top of a palo verde tree:

Pipevine Sex best 9-24-2010 8-40-29 AM 442x339

Two days ago, while on a bird walk, my buddy Sue and I saw a young butterfly emerge from its chrysalis. In this brief video you can see the flashes of color appear:

It was a beautiful Gulf Fritillary,

Gulf fritillary 1 9-10-2010 9-07-02 AM 3616x2712

but we had to move on before it had dried out and pumped up its wings.

The very early life of a butterfly is fraught with peril. See how I rescued one in my earlier post on Butterfly First Aid.