The Beneficial Lady Beetles: Good Luck Bugs or God’s Little Cows

J.B.S. Haldane, one of the founders of population genetics, is credited with saying, “If one could conclude as to the nature of the Creator from a study of creation it would appear that God has an inordinate fondness for stars and beetles.”  Like most quotes attributed to famous people, it is probably apocryphal, but the point is valid.  There are a lot of Coleoptera species in the world, not as many as there are stars in the sky, but 1 out of 4 animal species in the world is a beetle of some sort. Many people experience an inordinate queasiness around insects and other arthropods.  There are a few species, however, that rarely elicit distaste.  Of these the Coccinellidae or  Ladybugs (also called Lady Birds and Lady Bird Beetles) are particularly adored.  The most iconic of these are the jewel-like red and black spotted types, of which there are many.  All told there are some 5,000 species of ladybugs around the world, not all of which are red, around 450 in North America, and approximately 175 species in California alone.  All ladybugs share the endearing, rounded shape that their name, Coccinellidae (meaning “little sphere” – Note: some sources suggest that this name means “scarlet”), derives from.  These are primarily solitary little beetles that are found nearly everywhere there are a lot of plants, especially in gardens, fields, grasslands, and shrublands.

Convergent Ladybug (Hippodamia convergens) on manzanita leaf

Convergent Lady Beetle (Hippodamia convergens) on manzanita leaf

The rounded shape that gives ladybugs somewhat of a bumbling appearance is actually highly effective armor to protect them from ants.  “Why do they need protection from ants?” one might ask.  Well, contrary to their appearance, they are fierce and merciless predators, specializing in aphids.  Hungry ladybugs will eat a wide variety of insects, but to reproduce they must eat aphids and eat large quantities of them.  An adult Convergent Lady Beetle (Hippodamia convergens), a common and easily identifiable ladybug found in the Americas from Canada to northern Bolivia, eats 40-75 aphids a day with the larvae eating only slightly fewer.  Aphids have a special relationship with ants. Aphids by themselves are small, defenseless, and relatively harmless, but, as any gardener or farmer knows and fears, they can very quickly reach immense numbers.  Aphids live off of plant sap, sinking their mouthparts into soft plant tissue like miniature vampires.  Plant sap is high in sugars that the aphids excrete in the form of honeydew.  Ants, like many animals, have an affinity for sugar and collect the sweet honeydew from aphids, in some cases treating them not so differently from the way we treat free range cows.  In exchange for honeydew the ants protect the diminutive aphid herds from predators.  Predators such as the voracious and heavily armored ladybug. Farmers and gardeners have a particular fondness for ladybugs as they can potentially save a whole crop from devastation.  The name “Ladybug” or “Lady Beetle” supposedly derives from vast numbers of ladybugs descending on pest infested fields after villagers prayed to the Virgin Mary to protect their crops.  In Germany one of the names was Mary’s Chicken, in Sweden The Virgin Mary’s Golden Hen, in Spain Gods Little Cow, in Turkey they have the name Good Luck Bug, and in Yiddish they are called Moses’s Little Cow.  In Russia seeing a ladybug indicates that a wish will soon be granted or is an indication to make a wish.  Before Christianity took over northern Europe their name was tied with the Norse goddess Frejya rather than with Mary.  Nearly all the names for ladybugs indicate how well respected and loved they are, though there are a few names reflect the burning aspect of the chemical defense they use to deter larger predators. The Convergent Lady Beetle is particularly favored by farmers in the US as a natural pest control method.  Despite their solitary nature one acre of alfalfa suffering from an aphid infestation can support up to 50,000 ladybugs by Dr. Kenneth Hagen’s estimate.  Many farmers take preemptive steps to control aphid infestations by releasing ladybugs in bulk, purchasing buckets containing between 70,000 and 80,000 individuals per gallon.

Convergent Ladybug (Hippodamia convergens) in a hibernation swarm.

Convergent Lady Beetle (Hippodamia convergens) in a hibernation swarm.

If ladybugs are solitary, how does one collect 70,000 of them?  They migrate; I’ve mentioned insect migration before, but this is not the extraordinary long distance flight of dragon flies or monarch butterflies.  This is a short migration up into the hills and mountains where the ladybugs cluster in protected areas and wait for the weather to warm up. Ladybugs do not fly if the temperature drops below 55ºF (13ºC) and the Convergent Lady Beetle spends the cooler months in diapause, an insect analogue to hibernation.  In California, Convergent Lady Beetles living in the Central Valley head up into the Sierras while those closer to the coast find local hollows and protected areas to gather in.  They often show fidelity to specific sites and, in the Sierras, can gather in vast numbers.  Individual sites can have as much as 500 gallons of ladybugs, or more than 37 million individuals.  Collectors scoop these ladybugs up and sell them to agriculturalists around the country. In the coastal portions of California the distances the ladybugs travel to wintering sites is not as great and they do not gather in the same density.

Hippodamia convergens in Redwood Regional Park

Hippodamia convergens in Redwood Regional Park

One place to see Hippodamia convergens gathering is in Redwood Regional Park in Oakland.  There is one spot that they return to, a glade near one of the streams.  They coat the low growing and dead vegetation, branches, and logs in an intermittent film of slowly moving red gems.

Hippodamia convergens on dead vegetation

Hippodamia convergens on dead vegetation

In some spots they clump like globs of foam stuck to old hemlock stalks, in other areas they gather on lichen covered logs.

Hippodamia convergens on log

Hippodamia convergens on log

They are not completely dormant.  If you sit and watch them for a few minutes you will see them slowly mill about.

Hippodamia convergens on twig

Hippodamia convergens on twig

In a few places they form a nearly even coat over branches.

Hippodamia convergens covering a branch

Hippodamia convergens covering a branch

In other spots they cluster between the stalks of old flower-heads.

Hippodamia convergens on flower head

Hippodamia convergens on flower head

Finding these conglomerations of ladybugs is particularly exciting, in part as it is so shocking even when you are expecting it.  We have so few opportunities to see large numbers of wild animals in their natural environment any more that when we do it is particularly impacting, especially if it is of a type of animal we usually see as solitary individuals.  The ladybugs are also very pretty, which is always a bonus. *** Macro photos taken with a 70-300mm lens and kenko macro-tubes at a high ISO due to the late time of day and shade.

Hummingbirds – miracles of evolution

Of all birds hummingbirds are one of the most fun to watch.  They are fast, colorful, and tiny, the smallest ones roughly the same size as a large moth or butterfly.  They are probably best known for their maneuverability.

Anna’s Hummingbird (Calypte anna) coming in for a landing. Note the small tail, the curve of the body, and the large wing muscles.

These birds are compact and extremely well muscled.  Their tails are short and flexible, notice how the tail of the Anna’s Hummingbird in the above photo is curved to the side and folded to cup the air to assist in guiding the bird in to its landing spot.  Their wings are short with thick muscles covering the limbs and have a range of motion far greater than that of other birds.

The name Hummingbird comes from the noise of their wings beating at 25 beats per second, about 1500 beats per minute. This high wing-beat and the extraordinary wing flexibility allows hummingbirds to hover far more effectively and energy efficiently than any other bird.

To hover they flap their wings in a figure-8 pattern, generating lift on both the down and upstroke.  Approximately 75% of the life of generated on the down-stroke with the remainder on the up-stroke.  The University of Texas has some nice graphs and charts providing more detailed information on how this works.

Anna’s Hummingbird hovering in front of Tobacco Tree (Nicotiana glauca) flowers

In to achieve this maneuverability hummingbirds give up the ability to glide.  In effect they have no low energy flight, they are always running at near full speed.  A 170 pound person would need to eat (and metabolize) 130 pounds of bread a day to keep up with energy output of a hummingbird.  Their energy output is so great that they enter torpor at night, a sort of hibernation.  If they did not do this the hummingbird would starve to death during the night.

Hummingbird flight characteristics are very nearly a blend of bird and insect methods of achieving lift.

Hummingbirds are generally extremely colorful, especially the males.  Like many birds this color is not pigment generated, but is the result of highly specialized feathers light refracting feathers.  Think of oil on water, that rainbow sheen that you see when light reflects from it.  Birds use the same technique, but in a far more specialized way.  Rather than an undifferentiated rainbow of colors the micro-structure of the feathers refracts only specific colors.  The natural color of the feathers is a dark brown, almost black.

Anna’s Hummingbird (Calypte anna) perched on a non-native Tobacco Tree (Nicotiana glauca)

I know I’ve used this photo before, but it illustrates the refraction vs pigment issue well.  The bold purple-pink behind the bird’s eyes is the color we associate with the male Anna’s Hummingbird’s head and gorget (the throat portion).  The dark, almost black, feathers are at the wrong angle to reflect the light and show the natural dark color of their pigment.

The tree in these photos is a Tobacco Tree (Nicotiana glauca), not native to North America, but native to South America, a place where there is a stunning variety of hummingbirds.  This tree and hummingbirds have a long relationship and have mutually evolved to reinforce that relationship.  Hummingbirds and may other birds and insects (and not a few mammals and reptiles as it turns out) drink nectar from flowers.  Not everyone who drinks the nectar will pollinate the plant, thus special relationships evolve.  Plants with long tube-like flowers (penstemon, humming-bird sage, tobacco, monkey flowers, heliconia, etc) are specialized to provide nectar for animals with long tongues that can reach the nectar.

Hummingbird tongue

Hummingbirds not only have long, narrow beaks, they have long, feathery tongues with which to lap up nectar hidden deep inside the tube-like flowers.  As they drink the plant deposits pollen on the beak and sometimes the bird’s head (two photos up you can see the pollen discoloring the hummingbird’s beak).  The next flower the bird visits gets a little pollen from the previous flower and the plant is happy.

A quick look at the shape and color of flowers will often give you a good sense of what type of animal the plant relies on for pollination.

Hummingbird catching insects under a Coast Live Oak

Hummingbirds need protein as well.  Some, such as the Anna’s Hummingbird, catch insects in flight, many others raid spiderwebs for insects.  Here in North America this is a relatively safe prospect, but in parts of South America there are spiders that will happily catch and eat a hummingbird and spin webs more than strong enough to trap the birds.

Hummingbirds have such a need for vast quantities of high energy foods that they are often extremely territorial, engaging in vicious fights and high speed chases.  Like most animals they would rather warn opponents off than waste energy fighting them.  Different species have various methods of letting others know how tough they are.

Anna’s Hummingbird staking out its territory

The little fellow above is marking out territory by fluffing out his head feathers.

One of the most amazing things about hummingbirds to me is that they migrate long distance, some species crossing the Gulf of Mexico in one long flight with no food.  At the shortest distance this is a flight of 480 miles, many birds fly closer to 600 miles to make this open water trip.  For a bird that only weights several ounces, cannot glide, and needs to eat constantly this is a truly remarkable voyage.

On a final note, hummingbirds are far more intelligent than most people realize.  Their memories are phenomenal, allowing them to keep track of individual flowers within their territories and when they were last visited for nectar.  They have the largest brain-to-body size of any bird.

Loons – the clumsy birds

If you’ve spent time on an undeveloped lake in northern North America or Europe you’ve probably seen or heard loons.  Their calls are loud and eerie, ringing out over still water and carrying far before fading amongst the trees.

Here in Vermont the Common Loons (Gavia immer) have finished nesting, the young have hatched, and the adults are teaching their young how to survive.  Over the past few months they’ve flown in from their winter grounds, found nesting spots, defended them, reproduced, and will stay until the first ice begins to cover the lakes.  The adults carry immature young on their backs.

Kevin T. Karlson photography – common loon with chicks

When the time comes for over-wintering loons fly to the oceans.  In the US there is an excellent loon tracking program that allows you to watch the movements of individual loons over the seasons.

Loons are large waterfowl with a distinct black and white pattern, reminiscent of Penguins, Auks, Razorbills, Puffins, Terns, the questionably named Imperial Shag, and a host of others.  These birds are patterned white on the belly and black on the back for the same reason that Orca and other aquatic predators are; from below the white blends into the sky, and from the above the black blends into the water (or ground), providing camouflage from both prey and predators.

Loons are excellent fliers with long, surprisingly narrow wings

Loons are excellent flyer and fantastic swimmers, but have difficulty on the ground.  Their large bodies are front heavy and they cannot stand upright, as a result they push themselves along the ground, sliding on their bellies. The name Loon derives from Scandinavian names for lame or clumsy, “lúinn” in Icelandic and “lam” in Swedish.

Their inability to walk means that their nests must be close to the water and that the nests must be in well protected places, usually islands or extremely wet peninsulas.  As more and more lake sides are developed there is less and less nesting habitat for loons.  In addition a pair of loons needs 5-20 hectares (12-50 acres) of clear undisturbed water on a lake with many small bays and nooks and a healthy fish population.  Boats and swimmers can easily disturb nesting loons and studies indicate large reductions in nesting success in areas where people come into close contact with nesting loons.

There are few places that meet the nesting requirements and loons are highly territorial during nesting season.

Most of the time loons are heard, not seen, and when seen it is usually from at least a mild distance.  Several weeks ago I came across a freshly dead loon on the shore of a small pond.  Finding dead animals is always interesting as you have an opportunity to look at them up close and discover things you wouldn’t otherwise know.

The background of this particular loon is that it was an undersized male, blind in one eye, that (according to the banding codes) was new to the area.  It fought with the male of an established nesting pair and lost the fight.  A fellow from the Vermont Center for Ecosystem Studies moved the loon to a nearby lake where it stayed for several days, seemingly falling into poorer and poorer health until I found it on the beach.  Upon request I collected the loon so that it could be sent to one of the research labs and an autopsy done on it.

Small male loon found dead

Small male loon found dead

The first thing that caught my eye was the sleek iridescence of the feathers, tending towards a blue-purple on the neck and with an oily sheen on the black back feathers, but it was the legs that fascinated me.  Chicken, duck, and most other familiar birds have round legs.  This makes sense, these birds must support their weight while walking, or waddling in some cases.  Loons don’t walk so their legs don’t need to be especially strong side-to side.  They do need to cut smoothly through the water however, and as such they are blade-like in shape presenting a narrow front to reduce drag.

The white neck feathers stand proud from the black feathers

The white feathers that ring the neck stand proud, rising 2-3mm above a background of short, fine, dense black feathers.  Loons are cold weather birds and, like all water birds, they have dense feathers.  I did not realize just how dense those feathers are though.  Loon feathers feel like rich fur, not feathers, almost felt-like in texture and density.

White speckled back feathers

The white speckles on the loon’s back remind me of an Escher print.

Here in Vermont loons are popular animals and there has been some good work done to protect loon habitat.  As a result, loon breeding success is higher in this state than the national average.  Bans on lead sinkers for fishing have helped the loon population as well as fewer individuals are swallowing the lead and getting poisoned from the metal.

Birds, but especially Warblers

Birds occupy a place in our imagination like few other animals.  They are colorful, have beautiful songs, and they can fly!  Who doesn’t wish they could fly?

Young Red-tailed Hawk (Buteo jamaicensis) before the tail turns red

We eat them, decorate our bodies with their feathers, listen to their songs, and keep them as pets.  In westerns the high-pitched keening cry of the Red-tailed Hawk symbolizes the openness and loneliness of the range, setting the mood and implying that the rugged, lone gunman is as comfortable on the dusty range as the hawk is in the air.

Traditional societies have based dances on the mating dances of birds, clothing has been influenced by the color and patterns of birds, and we assign symbolism to specific birds; doves for peace, hawks for aggression, eagles for freedom, the unfortunate dodo as a dead-end in stupidity, and many more.

Here in the US the we chose the Bald Eagle to symbolize our nation, choosing a bird that is at least as much of a scavenger as it is a hunter, over the objections of Benjamin Franklin.  Make of that what you will.

Some birds live only a few years, others like parrots and albatrosses live as long as a healthy human.  Many birds can “fly” under water as well as in the air, the Water Ouzel of the American West, Loons, Cormorants, and Gannets that plunge into the water like falling rockets, diving many meters down to chase fish.  Some birds have given up the air entirely, Penguins retain their flight in the water, but the Ratities, an ancient lineage including Rheas in South America, Ostriches in Africa, Emus in Australia, and the extinct new Zealand Moa returned to their dinosaur origins, running at high speed on the ground, forgoing the air forever.

Corvids, crows and jays, Parrots, and Cockatoos are renowned for their intelligence, problem solving, and in the case of Corvids, tool use.  These birds rival small children and chimpanzees in their mental abilities.

Birds also can tell us about changes in climate and the environment.  Banding them allows for long-term identification of individuals.  Feathers can be analyzed for isotope ratios, telling what the birds have eaten and where.  Populations can be tracked to see how they respond to changes in environmental conditions.

Vermont Center for Ecosystem Studies employee banding a bird on Mt. Mansfield

I am not an ornithologist, I find birds to be largely mystifying.  I don’t seem to have the ear necessary to distinguish species based on their calls, a vital component of birding.  Despite this, I do greatly appreciate birds and try to photograph them when I can, in part to help me learn, in part because they are pretty, and in part because birds are often easier to see and are more prolific than many other animals.

Birding is a popular activity.  Of all groups involved in conservation and outdoor activities, birders have the highest average income, and companies that make the high quality spotting scopes and binoculars necessary for this activity adjust their prices accordingly.  Many of the most interesting and colorful birds are tiny and fast, necessitating patience and luck, or good equipment, or, most often, a combination of the two.

Warblers are popular birds to watch in New England.  New World Warblers are an often colorful group of small passerines, commonly called “perching birds”.  The name derives from their sparrow-like appearance.  Many of the New World Warblers over-winter in the neo-tropics, flying up to New England as the weather warms and food becomes available here.  Most of the ones I see are in the Septophaga genus, meaning “moth-eating”, though this is sometimes misreported as meaning “fly-eating”.  Others fall into the Cardellina and Geothlypis genera.  I am not sure what the origin of Cardellina is.  Several of the birds in this genus are reddish or pink, and others have a lovely song, it may be a comment on a loose similarity to Cardinals.  Geothlypis roughly means “earth warbler”, perhaps reflecting the essential silliness of many scientific names.

Over the last few years I have managed to take photos of a small number of them:

Canada Warbler (Cardellina canadensis)

This lovely little Canada Warbler was on the ridge-line of Shenandoah National Park and didn’t care that I was nearby.  I heard the song and had to hunt a little bit to find him.

Common Yellow Throat (Geothlypis trichas)

This Common Yellow Throat followed me through the woods as I waded through ferns and sedges in a wet wooded meadow near my house.  It didn’t seem afraid of me at all, more curious than anything.  It kept the caterpillars in its beak, suggesting that there was a nest with young close by.

Black-throated Green Warbler (Setophaga virens)

A few months back I heard a soft but rapid twittering in the woods on my morning walk.  Over my head a flock of 5 or so little birds flitted back and forth faster than I could follow.  One of them briefly touched down and held still for just long enough to snap this photo.  From there I was able to figure out that they were Black-throated Green Warblers.

Black-throated Blue Warbler (Setophaga caerulescens)

On our bird-banding day on Mt. Mansfield this little Black-throated Blue Warbler was found in the mist net.

Yellow-rumped Warbler (Setophaga coronata) western subspecies on the sunflower stalk, eastern subspecies held in hands

The Yellow-rumped Warblers may be the easiest of the warblers to see.  They range from California to New England and have been divided into several sub-species that are nearly indistinguishable to my eye.  The eastern variant is known as the Myrtle Warbler (Setophaga coronata coronata) and the western variant as Audubon’s Warbler (Setophaga coronata auduboni), but they are both Yellow-rumped Warblers to me.

Yellow Warbler (Setophaga petechia)

Finally this small Yellow Warbler was in an apple tree in deep shade.  It sat and watched me for several minutes, then flitted away.

Learning these birds has given me a greater appreciation for them, although I must admit that the task of learning these little guys would have been much more difficult if I couldn’t take photos of them and take the time to look closely at their details.

The Mighty Dragonfly

Of all insects there are few that capture our attention and interest the way dragonflies do.  They have, perhaps, the coolest, most evocative name of any group of insects: Dragonfly.  In English there are a great number of other common categorical names: Devil’s Darning Needle, Snake Doctor, and Ear Cutter among others.  Many of these names come from the mystifying apparent fear of nature that crops up over and over in European views of the world.  Many European cultures viewed dragonflies as sinister creatures, servants of the devil, in league with other evils such as snakes and bats.

Other cultures, often more agrarian ones, had a far more benign view of dragonflies, based, perhaps, on the recognition of their fundamental role in controlling populations of pest insects of all sorts.  An archaic name for the Japanese Islands is Akitsushima (秋津島), the Dragonfly Islands, where dragonflies symbolized courage, strength, and happiness.  For some native American tribes dragonflies symbolized clean, pure water, swiftness, and agility.  In the modern world dragonflies are good indicators of environmental heath, indicating a robustly functioning ecosystem.

Libellula quadrimaculata – Four Spotted Skimmer
The Alaskan State Insect

Dragonflies and their close relatives, Damselflies, come in a dazzling array of colors and patterns, ranging in size from less than  an inch long up to the South American Megaloprepus caerulatus with a wingspan of over 7 inches.  The largest dragonfly we know of is from the 300 million year old fossil Meganeura that had a wingspan of over 2 feet.

Dragonflies are powerful hunters, both in their nymph and adult stages.  Dragonfly nymphs are aquatic and prey on any animal or insect they can grab with their claws or their extendible jaws.  Insects, small fish, tadpoles, and small amphibians are all food for these voracious predators.  The nymphs are large, and, in turn, are prey for a wide range of other animals, insects, birds, and fish.  Elva Paulson has some wonderful watercolors of a dragonfly emerging from its nymph stage.  Humans are included as predators, many Asian cultures eating both dragonfly nymphs and adult dragonflies as delicacies.  One of the most tasty things I’ve eaten (from a long list of foods most people would consider to be unusual) was a plate of deep fried dragonfly larvae.  Absolutely delicious.  In Beijing I would sometimes find adult dragonflies candied in liquid sugar, their wings crispy with the hardened sugar.

Unknown green dragonfly – note the barbs on the forelegs for catching prey

The adult phase of a dragonfly’s life is short, in temperate climates only the length of the summer.  This is their mating stage and it takes them between 2 months and 6 years living under water to reach this stage.  Dragonflies are extremely active during this mating phase and must eat often.  They have enormous eyes giving nearly 360 vision, incredibly swift reactions, fast, powerful flight, and wicked barbs on their legs to assist capturing insects in flight.  The inset above shows these barbs.

Libellula exusta – White Corporal (I think)
eating its prey

The common names of dragonflies often reflect their speed or their abilities as hunters.  Meadow-hawk is one of my favorite names, and watching one dart away to catch an insect and return to its roost to devour it definitely brings hawks to mind.

Libellula quadrimaculata – Four Spotted Skimmer
note the different wing heights

Dragonflies are powerful fliers.  They have been clocked at over 35 miles an hour, fast enough to get a speeding ticket in a school zone, and, like hummingbirds, can fly forwards, backwards, sideways, up and down, and hover.  Their backs are sloped where their wings anchor, placing each pair at different heights, allowing for tremendous wing mobility.  Some species of dragonfly migrate, but the scale of some of those migrations has only recently been realized.  One dragonfly species in particular, the Globe Skimmer (Pantala flavescens) flies from India to Africa and back, island hopping cross the Indian Ocean, making open water crossings of nearly 1000km (620 miles) between island stops.  The only places they can breed are at the Indian and African ends of the migration, many of the islands they use as stopover points do not have sufficient freshwater for dragonflies to breed.  This is a stunning feat of flying for an insect and may be a behavior that evolved as a result of plate tectonics splitting India and Africa apart, eventually thrusting India into Asia.  If so, this migration could have begun 135 millions years ago.  Unfortunately, we have no reliable way of telling if this is the case.

Last year was a good year for dragonflies in Vermont, and this year looks like it is shaping up to be a good one as well.  The ecologist in me cannot help wondering why and one idea is that it may be linked to the calamitous drop in bat populations as a result of white-nose disease, a fungus that infects hibernating bats, weakening and eventually killing them.  It may be that adult dragonflies have more to eat with fewer bats and a greater percentage of them are surviving through the summer.  There is a historical precedent for this sort of boom in insect populations.  During the Great Leap Forward, Chairman Mao promoted a policy of killing off all things he thought were eating grain, birds amongst these.  With the crash in bird populations in China the insect population exploded.

Unidentified dragonfly – maybe a Darner of some sort

I am happy to see the dragonflies here.  Their presence means that the water is clean, we will have fewer mosquitoes, midges, and black-flies, and they are extraordinarily beautiful creatures.

Three-hundred twenty-five millions years old and going strong.  They have it figured out!