Birding Panama, The Canopy Tower

Green Honeycreeper, Chlorophanes spiza

 

I arrived in Panama at dusk with just enough time to go through customs, locate the driver, and arrive at the Canopy Tower in time for the introductory dinner to the WINGS tour.  The other 9 guests, hailing from throughout the U.S. and U.K., had beat me to this famous birding destination and were clearly excited at what they had already seen in just a few daylight hours.  My catch-up birding had to wait until dawn.  The plan was to meet on the observation deck at sunrise for a pre-breakfast session.

The Canopy Tower

It was a little like a childhood Christmas Eve–I couldn’t sleep.  So about 5:30AM I lugged my camera and telephoto lens, binos, and scope up several flights, through the dining area, and up the ship-style stairs and hatch, onto the observation deck.  It was still dark but I could barely make-out the canopy below.  I was alone, but someone had stationed several pots of hot coffee there.  This was going to be a great week.

Dawn on the deck

Sunrise brought out the other guests, the guides, and of course the birds.  They came fast and furious, the birds that is; almost too much of a good thing.  It was difficult to keep up with all the sightings called out by fellow birders and guides alike.  The laser pointer was a great help in locating the often sleuthy birds hiding in the thick canopy.  I saw our familiar migrating warblers, now in their winter home, but the real treats were the colorful tropical residents I had never seen or photographed.

Golden-crowned Spadebill, Platyrinchus coronatus

The tower is a reclaimed former U.S. Air Force radar site built in 1965 and abandoned when the Canal Zone was transferred to Panama.  Luckily Raul Arias de Para had a vision for this “giant beer can” and acquired it in 1996, transforming it into a mecca for birders and ecotourism.  The lower floors are for lodging, each room with a window opening to the rain forest.  The upper floor houses a large dining room, lounge, and library.  The tower sits on top of a tall hill within the Soberania National Park, about 2 miles from the canal.

Breakfast in the Tower

Gartered Trogon, Trogon caligatus

Ants figure prominently in the taxonomy of Panamanian birds.  There are Antbirds, Antpittas, Antshrikes, Ant-Tanagers, Antthrushes, Antvireos, and Antwrens.  What’s their schtick?  Even the tropical novice trudging through the rainforest can’t help but notice the numerous ant highways traversing the trails.  At first you see a long line of upright leaves, seemingly moving by magic.  Closer inspection shows the leaves are carried by Leafcutter Ants, heading to who knows where.

Spotted Antbird, Hylophylax naevioides

The birds don’t eat the crusty ants themselves, but have learned to follow the ant swarms, ambushing the other hapless creatures that are fleeing the marauding Army Ants.  We birders in turn seek the birds, that seek the insects, that escape the ants.  Some claim that you can hear an approaching ant swarm as their million of feet rustle the leaves on the jungle floor.  In short, when encountering an ant swarm, get ready.  The birds can’t be far behind.

Red-capped Manakin, Pipra mentalis

I was in Panama this November, near the end of the rainy season.  Rain, sweat, dew, puddles, mud, humidity, and any other form of moisture you can imagine were part of the experience.  No AC, nothing stays dry, just get use to being hot and damp in order to enjoy birding in the rainforest.  I even had difficulty keeping my eyeglasses and lenses from fogging, often when that special “rare bird” was making an infrequent appearance.  You can’t win them all.

Shining Honeycreeper, Cyanerpes spiza

Shining Honeycreeper, (female)

What is it about the tropics that fosters so much spectacular color in its resident birds?  Oh, we have our Cardinal and Jays, but most of our residents pale against the tropical gems.  The Blue Cotinga, various Manakins, Trogons, Motmots, and Honeycreepers startle one when first seen.  Then there are the iridescent Hummingbirds–we saw 10 species of these beauties during the week.

Blue-chested Hummingbird, Amazilia amabilis

Snowy-bellied Hummingbird, Amazilia edward

Birding in the thick jungle, and bird photography in particular are difficult.  Good guides are invaluable, and we had two of the best.  Gavin Bieber, from Tucson Arizona, has been guiding in Panama several times a year for 10 years.  His patience and expertise were readily apparent, and several in our group had birded with him before.  I particularly appreciated his knowledge and discussion of avian taxonomy, explaining in the field how a particular birds fits into the greater classification scheme.  His birding banter, both serious and in jest, made these day-long jaunts wonderful.

Whooping Motmot, Momotus subrufescens

Common Tody-Flycatcher, Todirostrum cinereum

Our local guide was Danilo Rodriquez Jr., a member of the Canopy Tower staff.  How does such a young person become such an expert birder?  His whistles and tweets could seemingly mimic and call-in any species.  I still can’t figure out how he spotted that Black-and-White Owl high in the tree, or that Great Potoo hugging the trunk.  Between Gavin and Danilo I felt we were birding among the giants of their profession.

Slaty-tailed Trogon, Trogon massena

The Tower was our base of operation for the week, but the guides also took us to famous near-by hotspots including the Pipeline Road, Ammo Dump Pond, Gamboa, Colon, and the amazing Hummingbird House of Jerry and Linda Harrison.  I’ll have to leave a description of those to another day and post.

White-necked Jacobin, Florisuga mellivora

I know, it’s not about the numbers, but they are impressive.  Panama, a small country at the narrow intersection of two continents, has recorded sightings of 978 bird species, many more than the entire U.S.  Many of our northern birds reach the southern limit of their ranges at the isthmus, and likewise, many of the South American birds reach their northern limits in the same area.  This creates an inviting avian menagerie in Panama.  My total count for the trip was 211 species, (I would have seen a few more except for foggy glasses) and my life list jumped by 148, but who’s counting.

The Flight of Birds; Fair or Foul?

I was minding my own business at the desk by the window when WHACK, a Cardinal crashed into the glass.  I rushed outside to look for a body in the hedge, or at least a stunned bird, but found nothing, not even a red feather.  He must have survived.  It got me thinking about flight.  It’s marvelous and amazing and we terrestrial-bound species are jealous of the birds, but it does come with risks and at a price.  What are the risks and what exactly have the birds given up when they evolved this specialized skill.

Northern Cardinal, Cardinalis cardinalis

I count five groups that have acquired the ability to fly, (omitting the gliding frogs and squirrels).  They are the myriad insects, the extinct dinosaurs–Pterosaurs, the mammalian bats, the birds, and Homo sapiens, since Kitty Hawk.  You must admit that at least with insects and birds, flight has been a successful strategy, with Aves flying around for 150 million years since Archaeopteryx, and insects for even longer.  This compares with a meagre 20 million years for Hominids on earth, with flight mastered by us just 115 years ago.

Brown Pelican, Pelicans occidentalis

There are, of course, obvious advantages of bird flight.  They can get from point A to point B quickly, whether its to find food, escape a predator, or chase a prospective mate.  The destination may just be across the yard or a migration of thousands of miles. Their flying skills include, hovering, take-offs and landings, on either land or water, soaring, gliding, and high speed dives.  They can catch a fly on the wing and even copulate in mid-air.  Very impressive.

Red-shouldered Hawk, Buteo lineatus

There are, however, obvious physical risks to flight.  My office window, multiplied by millions is an example.  Add to that the glass of towering skyscrapers, burgeoning wind farms, and power lines, and you have some real flight hazards.  Fall migration itself takes a huge toll on the young birds.  That’s why the spring migration is less crowded, returning to us just the survivors.

Limpkin, Aramus guarauna

But I’m more interested in the anatomic and physiologic adaptations that have evolved and made flight possible, and what price Aves have paid for this specialization.  The upper extremity of birds has reduced the five digits of its ancestors to three and these serve as the anchors for the primary flight feathers.  The wing is a wonderful and highly specific adaptation for flight, but useless for grasping a tool or playing the piano.  No matter; birds have evolved a flexible neck and versatile beak and tongue to partially offset these deficits.

Rose-ringed Parakeet, Psittacula krameri

What about size?  It does matter for birds.  Flight requires the birds to be relatively small and light.  When you double the length of a bird you increase its weight 8-fold.  Even though the large Golden Eagle only weighs 15 pounds it requires an 8-foot wingspan to fly.

Black Vulture, Coragyps atratus

The physics of flight applies to the birds, just as it did for the Wright brothers.  There must be air flowing over the wing or airfoil to create enough lift to overcome the drag.  Flapping adds greatly to the lift, but weight is still a limiting factor.  Just recall the spectacle of the heavy swan or goose, beating its wings while running across the pond, in its onerous fight to become airborne.

Osprey, Pandion haliaetus

Experts debate how the Pterosaurs and ancient birds “learned” to fly.  One camp suggests a “tree-down” approach, falling or gliding from a height, similar to flying squirrels.  Another group suggests a “ground-up” technique, running or leaping into the air, similar to our struggling swan.  I doubt we’ll ever know for sure.

Laysan Albatross, Phoebastria immutabilis

Birds have also solved the weight issue by their light, hollow bones, ideal for flight but lacking somewhat in strength–another compromise.  “Light as a feather”, the saying goes.  The evolution of the feather figures centrally in the history of flying animals.  Experts now believe feathers evolved long before flight.  Once we pictured dinosaurs as hairless, leathery reptiles, but now learn that some were actually adorned with colorful feathers.  The only question is whether their feathers were for insulation or for sexual ornamentation, but clearly they were not, at least initially, useful for flight.

Belted Kingfisher, Ceryle alcyon

The weight restrictions of flight also require that a bird brain remain relatively small, and surrounded by only a thin skull.  Most of its brain is devoted to eyesight, so highly perfected in raptors, and much of the rest to the regulation of basic functions and the intricate movements of flight.  Although much has been written about the intelligence of birds, (primarily the Corvids), don’t get carried away.  They will not be writing a Beethoven symphony any time soon, or even running for political office.

Prairie Warbler, Dendroica discolor

The warm-blooded, hyperactive, flying birds are massive consumers of energy.  Their high metabolic rates require a never-ending search for food (using energy in the process) for both themselves and their young.  It is a bird’s greatest mission everyday.  The avian respiratory system is also a unique and complicated adaptation of rigid lungs, multiple air sacs, and unidirectional air flow, all designed to supply richly oxygenated blood to meet their high energy demands.

Sandwich Tern, Sterna sandvicensis

It’s interesting that some birds have given up flight completely.  You wonder why.  For Penguins the rudimentary wings are now used for swimming, while the large Ostriches of the savannas of Africa use their downy feathers and wings for shade.  The flightless Dodo birds of the Mauritius Island in the Indian Ocean were doing just fine on the ground until discovered by Dutch sailors in 1598.  The vulnerable bird was easy prey for man and his contaminants and the Dodo is now extinct.  Unfortunately its name has become synonymous with naiveté and stupidity.

Wood Stork, Mycteria americana

So the birds have paid some price for their lives in the sky.  We humans need to keep this in mind as we stretch our frontiers upward, even to the Moon and Mars.  I consider Homo sapiens now a flying animal, similar to the birds.  We are part of nature and not just an outside observer looking in.  Never mind that our “wings” are metal and rivets and computers; they are merely our adaptations, the products of our brains, and our unique ticket to the wonders of flight.

The Wright brothers, Homo sapiens, 1903