Anna's Hummingbirds at Effie Yeaw

October 15, 2015

Written by Thom Parrish

There is a cottonwood tree close to the river, past where the observation trail fades into cobbles; the bare forked top branches have long been the favorite perch for a certain male Anna’s Hummingbird. The sight of this hummer has been a consistent and reliable one that I’ve come to enjoy keeping an eye out for when taking this trail to the river.

This past Sunday morning I saw him again at his perch chattering away in the wind. The Anna’s Hummingbird has a long breeding season of half of the year, beginning early in the winter and lasting until the end of spring.

The moment before the drop
It appears that my cottonwood Anna friend is hoping to get the season started early. I watched him launch from his perch and soar over 100 feet straight up until he was but a speck against the blue, he paused for moment and then dropped like a dart towards the ground. A few feet from the ground, he arced his trajectory back up, sharply whipping his tail and producing a loud “chirp.” He repeated his “U” shaped courtship dive several times before resting again atop his cottonwood.

Not far from this male Anna’s cotton wood is a series of tall straight eucalyptus trunks that has come to be known as “the pirate ship.” This is sometimes a great spot to see multiple hummers at once in high speed action. Eucalyptus buds are actually one of the Anna’s favorite sources of nectar.

The presence of migratory hummingbirds has long been a part of the American Parkway’s natural history; however the year-round residency of Anna’s in the Parkway is relatively new. Historically the breeding and nesting grounds for the Anna’s were limited to the Baja area of Southern California. The arrival and spread of the Australian eucalyptus tree throughout California as well as widespread planting of garden flowers in the late 19th and early 20th century is largely credited for the Anna’s wide range expansion. By the mid-20th century Anna’s Hummingbirds became a common sight year round in California’s Central Valley. The Anna’s is the most common hummingbird found on the west coast and has the northern most range of any hummer, extending up into Canada. They are the only hummer species in the Central Valley that does not migrate during the cold season. Their conservation status lists them as a species of least concern, LC.

At Effie Yeaw, the Nature Center’s courtyard is another excellent location to view hummers. The red fuchsia planted in front of the Assembly Building is one of their favorite flowers to visit.

The Anna’s Hummingbird, Calypte anna, was named after Princess Anna de Belle Massena, a 19th century French noblewomen for whom famed French naturalist Rene Primevere Lesson collected specimens. The Anna’s are recognizable by their iridescent emerald green back, a pale gray speckled belly and crimson encrusted gorget. The term “gorget” comes from a piece of protective armor worn around the neck, used by knights. The red gorget of the male covers the entire neck, face and crown (the only North American hummingbird whose gorget extends over the crown). The female Anna has a green crown and a smaller red central throat patch.The gorget may not always reflect the brilliant shimmering red, at times it may appear even black. The throat feathers contain thin film-like layers of “platelets,” set like iridescent tiles against a darker background. Sun light reflects and refracts off these tiles creating color in the manner of sun glinting off a film of oil on water. A hummingbird uses the bright reflection from their gorget to signal other hummers as well as in attracting a mate. They can subdue the reflection with a turn of their head when they wish to remain inconspicuous.

Their tiny size and delicate jewel-like appearance is in no way a reflection of their behavior; Anna’s are extremely territorial and aggressive towards one another. They begin to exhibit aggression towards other hummers almost from the moment they take flight and find a source of nectar. Male and female hummers will claim their own separate territories and will defend them against all comers of either sex. When dive bombing threats fail they will resort to aerial combat, attacking with beak and claw, sometimes even falling and scuffling on the ground. That being said, hummers are solitary birds. The only contact between two adult hummers other than when fighting is during mating; even that may last only a fraction of a second, after which both partners part ways with no further involvement. Hummingbirds do not form mated pairs. A male may mate with several female hummers during a season and will never see its own offspring. A female hummingbird will typically make two clutches of two eggs per season. Females will also mate with more than one partner during the mating season, often resulting in each egg being fertilized by a different father. The female will build the nest and care for the young on her own. The egg incubation period is up to 3 weeks and the time nesting before the babies fledge is also 3 weeks. Their nests are typically made on a sturdy horizontal tree or shrub branch 5 to 20 feet above the ground. Females build their nests using soft material often gathered from plant fluff and spider webs then reinforced with moss and lichen. For additional security female hummers have even been known to build their nests near the nest of a hawk. Hawks typically don’t prey on hummingbirds and they keep away birds like scrub jays that are notorious for nest robbing.

Hummers are very curious birds, mostly when it comes to determining whether something is a threat, food source, or competition. Hummingbirds are brave when it comes to predator inspection. I have seen hummingbirds fly dangerously close in front of cats, almost as if taunting. Most of the time a hummingbird can evade a predator with ease, but of all animals cats are the number one killer of hummingbirds. Other animals that make attempts to prey on hummers, especially nesting chicks, include jays and crows. Because of their small size hummingbirds must also worry about large predatory insects. Preying mantises have been known to lay in wait near flowers and feeders to ambush unaware hummers. Dragonflies have also been known to prey on nesting hummingbird babies. Last Monday just outside the Nature Center I observed what I believe was hummingbird predator inspection. I was watching the western screech owl perched in front of its tree cavity in the evening just after 6pm. I was surprised when a hummingbird flew directly in front of the screech and hovered there for a moment. The screech stared back at the hummer with seeming indifference and then the hummingbird darted away. Every ten minutes or so a hummingbird, not always the same one, would repeat this close hovering inspection of the owl. Sometimes the hummingbird would perch on a branch and watch the owl and other times even two hummers at once would hover close to investigate.

My earliest memory of seeing a hummingbird has stuck with me. I remember the breath-taking excitement I felt, watching it hover from one flower to another. I remember the feeling of having just witnessed something supernatural, something magical; a tiny, real-life faerie creature.

Of all the animals that have fascinated the human eye, hummingbirds rank at the top. Like the coyote, the hummingbird is a prominent figure in the mythology, artwork, and religions of ancient Native cultures throughout the Americas. The aerial photo shows a hummingbird geoglyph made by the ancient Nazca people of Peru. To some groups hummingbirds were the bringers of rain and the creators of stars. To others they were a manifestation of deceased loved ones and spirit guides. To the Aztecs the hummingbird was “Huitzilopochtli,” God of war. The Aztecs revered these tiny birds for their ferocity in combat. Aztec kings wore cloaks made entirely of hundreds of their emerald green pelts sewn together, a symbol of their divine status. The first Europeans to arrive in the Americas sent back incredible reports of animals that were a cross between an insect and a bird.

There are over 300 species of hummingbird, all of which are found solely upon the American continents. Emerging from the ancient plateaus of the South American rain forests, the ancestor of the hummingbird took a most unique evolutionary turn. Around 50 million years ago this ancestor began sipping the nectar from flowers for additional energy. The co-evolution of hummingbirds and hummingbird flowers since that time is truly one of the most exciting stories of adapting life on earth. The relationship and dependency between the two has produced the most accomplished animal flyer ever to take the air. The hummingbird is unrivaled as the greatest embodiment of kinetic energy that exists in the animal kingdom. The peregrine falcon has gained high notoriety for speed, but the hummingbird pound for pound is the fastest flying bird, able to reach speeds over 60 mph in straight flight. By keeping their wings rigid and rotating their shoulders in a twisting motion, hummers gain lift with each forward and backward stroke of the wing, enabling them to hover, rotate on the spot, as well as fly backward and upside down with precision. Their wings beat at on average 60-80 times per second. During a mating display some hummer wings beat as fast as 200 times per second!

The primary and secondary wing feathers of an Anna’s Hummingbird.

The wings aren’t the only thing on the tiny bird that hums, in flight their heart beats at an astounding 1,200 times a minute. The hummer’s unmatched aerial prowess however, comes at a great physical cost. Their extreme abilities place them at the edge of what is biologically possible! The world’s most extreme athlete naturally has the most extreme physical needs. Hummers have the highest oxygen demand of all vertebrates, as well as the highest metabolic demand of all warm-blooded vertebrates (with the exception of the shrew). How is the hummingbird able to meet these extreme energy demands? Nectar! Nectar is the life-line to the Hummingbird’s precarious existence. Each day a hummingbird must drink more than its own weight in nectar in order to survive. Their lives revolve around nectar (The average weight for an Anna’s Hummingbird by the way is just over 4g, less than a nickel). Hummingbirds are required to refuel on their precious sugar filled energy drinks on an average of every 15 minutes.

Many flowers that use hummingbirds as the primary messenger for their pollen evolved to be tube shaped and hang downward, like this red Penstemon, in order to make it difficult for insects to land.

Many hummingbird flowers also evolved to be the color red. Originally it was believed the reason for hummingbird plants to have evolved red flowers was because hummingbirds prefer the color red. The reason for the red color was not so much to attract the hummer however, as it was to remain hidden from bees! Because bees and other insects are red-green color blind, they will often skip these flowers leaving more nectar for the intended messenger, hummingbirds. In contrast a hummingbird that can see red may see the red color as a sign saying “no insects here, more nectar for you!” Hummingbirds will become curious and inspect other items that are the color red as well, not just flowers. If you are wearing a brightly colored piece of clothing you greatly increase your chances that a hummingbird will fly in for a close inspection.

Hummingbirds however, cannot live by nectar alone. They require protein to rebuild muscle and replace feathers. To obtain the required protein hummers consume small insects. To conserve energy hummingbirds spend up to 80% of their time perched.

In order to sleep through the night without the constant need to refuel on nectar, hummingbirds all but shut down during the night hours and fall into an extreme form of deep sleep known as torpor. Torpor is basically a nightly hibernation, a slumber nearly as deep as death (which probably sounds lovely to sleep deprived parents).

During torpor the hummer’s metabolic rate drops by as much as 95%. Its body temperature, heart rate and breathing drops to what is barely sufficient to maintain life. People who happen upon a hummingbird during torpor sleep often think the bird is dead. When the sun comes up and temperatures start to rise it may take a hummer up to 30 minutes to come out of torpor and return to normal (still less time than it takes me to fully wake-up most mornings). During torpor sleep is also the time, in which many older hummingbirds pass away, being unable to recover from this nightly near death experience. The average life span for a hummingbird in the wild is but 5 years.

Despite their extreme energy demands there are instances when a hummer can stay in the air for hours at a time. Every year thousands of Ruby-throated Hummingbirds make the non-stop flight across the Gulf of Mexico, a distance of over 500 miles. Exactly how they do this and what routes they take is still largely a mystery. As far as I know no one has ever attached a tracking device to a Ruby-throat to study this migration. There are reports from people who have observed them flying over sections the gulf and according to these reports the hummingbirds fly low over the water, speeding like darts through the wind only inches above the waves. Ruby-throats are not found in California, although there are a number of other migratory hummers that can be found in the Central Valley. These visiting hummers include the Allen’s, Costa’s, Rufous, Calliope, and Black-chinned Hummingbirds. I have not yet seen any of these other hummers at Effie Yeaw myself, but come next spring I will be on the look out!

To make the migration feat of endurance possible a hummingbird must first store up enough energy in fat by rapidly doubling its weight before departure. They do this by in-taking a shit load of sugar. During this time of extra sugar loading, hummers are known to fore-go their aerial dog-fights over nectar sources and even their fear of people in order to fuel up for the long flight. This accounts for the majority of photos and videos you can see online depicting dozens of hummers all sharing feeders together, or also of people feeding hummers nectar from their hand or even with feeders attached to head-gear. A group of hummers together like this is called a “bouquet” or a “charm”.

An amazing variety of humming bird feeders are available. I saw the feeders above for sale online. One looks like the hummingbird is tapping into that kid’s brain fluid. Can you imagine stepping outside and seeing your neighbor wearing this? Ha ha. This feeder helmet device sells for $80. Hummingbird feeders first became commercially available during the 1930’s. When used appropriately an artificial feeder can be a great way to appreciate and observe hummingbirds up close without any harm to bird’s natural way of life. Earlier this month I hung the red glass hummingbird feeder (below) from the porch behind the Nature Center. I saw the feeder take its first customer in less than an hour from putting it up!

What is the reason feeders like this works so well? It is because hummers are smart! Hummingbirds don’t need to be told what this device is for; they will come on their own to investigate. If the feeder nectar goes bad they know not to drink it. If a feeder becomes dry they don’t waste any time waiting for it to refill. Hummingbirds do not become dependent on feeders and they also do not stop migratory hummers from migrating. The level of intelligence in hummingbirds is still largely a mystery as they have not been studied by science as closely as has been done with say ravens and grey parrots, however the hummingbird has the largest brain to body size ratio of any bird. They can remember all the nectar sources they have visited within their territory and which ones contain sufficient nectar for return visits! A hummingbird doesn’t have the time to go around checking random flowers for nectar; their fuel level is always dangerously close to empty, like a small sports car with a one gallon tank. If a flower doesn’t produce enough nectar it simply moves on. Hummingbirds also do not lose out on essential vitamins and nutrients by using a feeder. They will continue to drink nectar from other plant sources as well as obtaining protein from eating small insects.

Hummingbirds have a long, elastic, translucent tongue. To lap nectar they stretch their long tongue down into the liquid. As the tongue stretches and contracts small grooves in the tongue that end in a forked tip carry the nectar up into their mouth like a tiny elastic micro-pump.

The recommended ratio of water to sugar in making feeder nectar is 4 parts water to 1 part sugar. Use of red dye is not recommended because the dye can be harmful to the bird and it is not necessary to attract them to the feeder. It is also recommended to rinse out the feeder once a week with warm water.

The back porch of the Nature Center provides a beautiful view into the preserve for visitors who are unable to do a lot of trail travel. Hanging this feeder from the porch I hope will provide additional magic and excitement for porch viewers as these real-life fairies of the preserve come by to visit.

Left Photo: Immature male Anna’s, with gorget not fully developed.; Right Photo: My Anna’s friend at the river, with gorget subdued.