Tuesday, January 29, 2013

Hawk Attack



For years I have fed songbirds at the feeder. It seems like the right thing to do and it’s fun to watch the antics of the little guys, as they cluster around the feeder holes, vying for access to its cornucopia. I know I’m offering them vital nutrients in these cold months, but I’ve also been concerned about predators attacking them and how I may be setting up the little guys.

A bunch of tasty morsels crowding around the feeder must create a tremendous attraction for hawks. I have suspected that sharp-shinned hawks might be lurking in the vicinity. I’ve read that they are a major predator around feeders, but had never spotted one…until a few days ago.

There have been numerous occasions when I’d notice that all the songbirds near the feeder had instantly transformed themselves from jerky little acrobats who were constantly on the move into feathery statues. It was as if some magic hand had waved and suddenly turned them into taxidermy figures. For several minutes the only move they’d dare make was an occasional blink of an eye. My guess is that a hawk had entered the arena and they knew that their survival lay in stillness. I never was able to spot a hawk, however, and soon the little guys would resume their furious activity.

It can be crucial to the survival of a tiny songbird to ingest a sufficient amount of food energy, especially on cold days. Their tiny bodies rapidly radiate heat, so they must eat an enormous amount to stay alive. The expression to “eat like a bird” is very misleading. They gorge themselves. A tiny chickadee requires some 16 calories a day. Now, that might not sound like much, but scale that bird up to a 150 pound human, and you get the equivalent of over 6,000 calories! Try eating that much every day and still try to fly—let alone waddle across the room!

In order to gobble up that many calories, a little songbird in the wild must be scouting for food nearly every waking hour. It needs to find several hundred bugs a day to survive. On a cold January day, that’s an overwhelming task. If, instead, the bird has access to a feeder that is stocked with black oil sunflower seeds, just a few dozen seeds a day provides all the nutrients it needs. It’s in bird heaven!

So I’m helping the little songbirds survive the harsh winter. But am I also setting them up for a hawk’s meal? Maybe so. As yet I haven’t actually seen a hawk, nor any tell-tale pile of feathers on the ground—signaling the remains of its birdie feast. I also know that many songbirds gathered together provide each other a degree of safety, since many eyes on the lookout can spot a foe quicker than one pair.

A few days ago I was finally witness to a spectacular hawk attack. I happened to be standing still near the feeder, when there was a sudden flurry of activity in the trumpet vine next to the feeder. I looked over to see a sharp-shinned hawk dive repeatedly at two chickadees who were receding as fast as they could into the protection of the vine’s branches. The much larger hawk could not get in to grab them, though he tried several times in the split second I watched the attack. It then spotted me and streaked off to a nearby tree, where it landed on a limb and balefully eyed me, as if resenting my interference.

I inched slowly toward the hawk, hoping to get a better look. What a beautiful bird! It turned its back on me, unceremoniously pooped, and flew off into the forest—leaving me trembling in wonder. Wow! I was torn between a sense of relief that he failed in his attack (my birdies were safe for now) and knowing that this beautiful raptor needed to eat too.

I regretted not having a camera at the ready, but so many of nature’s gifts that I receive pass too quickly for a photo. I may not have captured a picture of this delightful bird, but the vision is surely permanently seared into my memory. I was graced.

Monday, January 28, 2013

My Dog Has Fleas

I bought a microscope and have been having fun with it. Here is a head shot of a flea picked off my dog, at 200X.

Thursday, January 24, 2013

Brain Drain



An article in the 11/25/12 Washington Post by writer Emily Matchar is a soberingif not ominousaccount of how an increasing number of educated Americans are moving abroad, primarily to find decent employment. Today theres an all-time high of over six million Americans studying or working abroad. Young educated people are 3-5 times more likely to move abroad than they were just a few years ago.

These employment migrants are not leaving out of choice, but because they find a stifling employment environment in their home country. They graduate from college with a huge debt, often cant find a decent job in the field they studied, and face healthcare costs that are very steep, with inadequate coverage. If they do find employment in their chosen field, they too often face an atmosphere that discourages innovation and entrepreneurship.

More and more of these young professionals are discovering far better opportunities abroadespecially in fast-growing Eastern countries. They often get a higher salary, excellent healthcare, an exciting and challenging job in the field they studied, excellent and affordable housing, decent working hours, happy co-workers, and good public education for their kids.

A parallel trend is occurring for foreign students who come to America for a good college education. Many of them in the past have stuck around and built a career heremaking a positive contribution to our society. An increasing number of these graduates are now returning to their native countries, because employment opportunities are better there.

These are disturbing trends. Americas greatness is largely due to the opportunities we have historically offered people who came here from around the world. This country has been enriched by millions of capable, dedicated, and talented people who have migrated here for hundreds of years.

Have we now changed, so that we are no longer welcoming? Are we not the land of opportunity we have been, for so long? Its hard to find optimistic answers to these questions, as we continue to dumb down our public education, deny our citizens good healthcare, and stifle the creative atmosphere in our professions.



Tuesday, January 22, 2013

Bloated Tick

This was picked off my dog yesterday. It could have gotten twice this size or more, if left to suck longer. It shows the underside of the tick. Note the six legs on the left...they would have surrounded the tick's body, before bloating. Note the brown piece of the dog's skin still gripped in the tick's mouth. Note the various strings of dog hair that came out with the skin. Click on image for enlargement, if your stomach can take it.

Wednesday, January 16, 2013

After Masting Aftermath



As I was composing the earlier masting story ("Masting Aftermath", posted 2-3 weeks ago) about our local oak trees, I read an article in the autumn 2012 issue of Living Bird magazine (from Cornell University), on a similar process that is unfolding in the western US. Its another fascinating tale about the close relationship between animals and trees that periodically mastthis time in the higher elevations of Arizona and New Mexico. Its a very intimate alliance that has been forged for millions of years between two species that even share the same name: the pinyon pine and the Pinyon Jay. (Its an interesting byproduct of scientific custom that the birds name merits capital letters, while the tree must suffice with lower case letters.)

The symbiotic partnership between the bird and the tree has evolved over time, to the point that today, neither one of them can survive without the other. It is referred to by biologists as a mutualistic relationshipwherein each species derives benefit from their interdependence. The Pinyon Jays beak is long and sharp, having evolved specifically to extract seeds from pinyon pine cones. The seeds are very nutritious, but when not available, the birds nearly starve and their chicksif they have any that yearwill not survive.

As part of its bargain, the bird will plant the tree’s large seeds at distant locations, caching thousands of them during the years when the pines mast. The Pinyon Jay has evolved a special throat pouch, into which it can stuff over four dozen seeds! (And any one seed nearly fills its bill!) Monogamous mates will jam their pouch with the plentiful seeds and then fly off, wing-to-wing, and carefully cache the seeds, poking them into the ground. They specifically choose a location where no pinyon pines currently grow. (If that’s not a wonderful example of inherent intelligence, I don’t know what is!) Even though the birds memory is so good that researchers have determined it later retrieves some 95% of all its hidden seeds, a few do get forgotten, and some pinyon pines may later sprout in a new location.

This old partnership is in peril, howeverthreatening both the tree and the jay. Pinyon pine habitat is dramatically diminishing, as development, forest fires, and climate change take their toll on the trees. Recent dry years have fostered more fires; and those fires have worsened because of mistaken forest management in the west, that has discouraged forest fires in recent years and allowed an abundance of dry tinder to accumulate. Conservationists have monitored an alarming decrease in the population of both bird and tree.

The situation is aggravated by climate change—which is causing droughts and heat to worsen. The fates of the Pinyon Jay and the pinyon pineinextricably linked to each otheris shaky. There is a ray of hope here, however. The mutualistic connection between bird and tree has existed for millennia, and as climate change occurred in past eras, the pines were moved to more favorable locations, thanks to the propensity for the Pinyon Jay to cache seeds in virgin territory.

Will the Pinyon Jay be smart enough (they are a corvid, like crows, and are very intelligent) to find favorable new habitat for the pine, as climate change increases? The future is very uncertain for these two intertwined species. Its just one more example of the threat to many of natures species, as the globe warms and weather becomes increasingly chaotic.

Saturday, January 12, 2013

Senescent Cosmos



Most of us know that the universe is oldvery old. In fact, only in the last few years has science been able to nail down the birth date of the universe with any accuracy. We now know it all began 13.7 billion years ago. In fact, cosmologists are certain enough that theyre confident it wasn't 13.6 or 13.8 billion years ago, but quite exactly 13.7. Just a few years ago, cosmologists weren't sure but what the Big Bang's birthday could have been as little as eight billion years or more than 20 billion years ago. Progress occurs. Isn't it comforting to know just how long this universe has been around? Don't we all want to know our true age?

Science is always refining its knowledge. That's why it appeals to me. We humans think that we are the smartest kid on the planetary block—and maybe we are, but we need to stay humble enough to acknowledge that's there's always room for improvement in our understanding. That's what science is all about: constantly working to improve our limited understanding...realizing that if we keep our minds open and our questioning active, our knowledge will certainly grow.

A British team of cosmologists recently expanded our knowledge of star birth across the universe—and the news can be a little depressing, if we let it. Their bottom-line result: as of this date in the life of our universe, 95% of all the stars that will ever come alive have already been born. Forget how old the cosmos is or how much longer it has to go, it'll only see another measly 5% of its stars come into existence.

Just think if we were to say the same for the human race. We've been around as a unique species for only about 200,000 years. Of all the billions of people who have existed, if we were to have only another 5% to go, that's frightening! Terrifying! It says that we only have just another couple of hundred years to go, and that's the end of humans. Senescence has caught up with us and we are done!

Well, the same is true of the cosmos. What can ease our propensity to panic is that the stars live so incredibly much longer than we do. While Homo sapiens might last a few score years, your average star will hang around for billions of years. Time is relative.

Although cosmologists have nailed down the birth date of the universe, they have yet to get a handle on how long before it winks out. They are sure we have at least 100 billion years to go, and maybe trillions, before that last star dies. Well, that's a time span we flash-in-the-pan humans cannot begin to comprehendlet alone fret about.

Still, it's a sobering thought. Those British cosmologists determined that peak star formation in the universe was about 10 billion years ago, when the cosmos was just a 3.7 billion-year-old baby. At that point, half of all the stars that would ever be formed were burning. It's been downhill ever since. Go out and take a gander at the starry sky soon. In a few billion years it'll be a lot more sparse.