birds

Nature – Creatures of the Air

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“Oh that I had wings like a dove! then I would fly, and be at rest.”  Psalm 55:6

In the domain of hawk, gull and sparrow, physiology and aerial prowess are synonymous. A bird is simply a masterpiece of engineering—the perfect flying machine—supremely crafted by God and endowed with the attributes for a life in the skies. Its breast muscles, which operate its wings, are enormous, in some birds, comprising 33% of their total body weight. At the same time, a bird’s skeletal system is incredibly light. The bones of a pelican, with a wingspan of nearly six feet, weigh only about five ounces, yet they are strong and flexible enough to withstand the constant stress of maneuverable flight.

Add to this package highly efficient digestive and respiratory systems, a large and powerful heart, and feathers that streamline, insulate, and provide the necessary lift for wings and tail, and it is easy to understand how a bird in the air is described in Proverbs 30:18, 19 as a sight “too wonderful for me.”

The methods and techniques of flight generally fall into a few basic categories. Flapping or power flight involves a strong downward stroke that results in rapid lift and forward thrust. Generally, the larger the bird the slower it flaps its wings. In contrast, the hummingbird will beat its wings up to 80 times a second while performing what has been called the most versatile display of aerial skill in all of God’s creation. The tiny bird can hover or fly in all directions—forward, backward, or to the side, depending upon its needs. Its rigid wings move in a unique figure 8 motion, powered by exceptionally strong muscles and a flexible swivel joint at its shoulder. The tail works as a rudder controlling the direction of movement. Not surprisingly, the hummingbird expends tremendous amounts of energy and to survive, must consume twice its body weight in food every day.

Gliding and soaring are far less demanding forms of flight, yet once again, the elements of aeronautical design are clearly seen. The turkey vulture soars, riding on air deflected upward from cliffs as its wings work in harmony with the surrounding wind currents, while a heron spreads its enormous wings in a slow approach to its nest. Large primary feathers at the end of each wing offer precise control of both speed and direction. A similar design enables a condor to ride for hours on spirals of warm air. Again, a huge wing surface allows for effortless gliding as the bird of prey searches the valley floor for food.

But for all the soaring wonder and power that so abundantly fills the skies, perhaps the supreme testimony to the Creator’s gifts of flight and life itself is written on the tissue-thin wings of the Monarch butterfly. Its wings are driven by powerful muscles designed into the insect’s upper body, the thorax, essential for migration. Advancing steadily, they ride on rising columns of warm air that can elevate them thousands of feet. These expert gliders can travel more than 50 miles a day, flying upwards of 3,000 miles to reach their winter home.

God reveals Himself to man through the things He has made. Each day in the wonders of land, sky, and sea He presents us with a vivid picture of His existence and character. It is a continuing revelation, as exciting and diverse as the creatures He has brought into being. In the majestic grace of a bird or a butterfly in flight an eternal truth shines clear—the God of all creation is real and alive, His power and wisdom are without limit, and He cares and provides abundantly for the life that He has made.

Wonders of God’s Creation, Animal Kingdom: Great are Thy Works, ©2004.

Nature – Why Birds’ Feet Don’t Freeze

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A quick glance at a winter weather forecast is enough to make most of us grateful for our warm homes and thankful for those who work outdoors in these brutal conditions.

For the wildlife in our communities, there is no escaping the harsh realities of winter. In fact, many of these animals must spend time each day out in the snow and ice to find the food necessary for survival. Take the Canada goose, for instance. They are a familiar sight at our local lakes and ponds, whether they are frozen solid or not. How do they do it?

Like people and all mammals, birds are warm-blooded. Their body temperature remains constant—about 106 degrees. To maintain their body heat in freezing temperatures, their bodies have been designed with several specialized mechanisms.

Birds’ feet are little more than bone, sinew and scale, with very few nerves, and for birds such as geese, ducks, and other waterfowl that spend time on ice or in cold water, keeping their legs and feet warm is essential for survival. Birds rely on a vascular system called rete mirabile designed to keep their feet warm. In this system, the arteries and veins in the legs and feet are close together, allowing the blood to be warmed and cooled quickly.

Here is how it works. As warm, oxygenated blood leaves the heart in arteries moving toward the bird’s feet, it passes in close proximity to veins returning oxygenated blood back to the heart. This allows for a concurrent heat exchange. The exchange allows the warmth from the arterial blood to increase the temperature of the blood returning in the veins, which is colder after circulating to the bird’s extremities. The warmer arteries heat the cooler veins and the veins cool the arteries. And since the temperature of the bird’s feet is closer to the environmental temperature, they don’t lose as much heat as they would if they were at body temperature. Also, birds’ feet lack sweat glands, so they stay dry with no danger of freezing to a perch.

The heat exchange is just one way birds stay warm in winter. Many birds have a winter plumage with more feathers to better insulate their bodies. Some species, such as finches, add fat in winter to both better insulate themselves and provide an energy source.

Many small birds, though, cannot bulk up too much because it would affect how they fly. For these birds, such as chickadees, shivering helps them stay warm. Shivering in birds isn’t quite like it is for humans. When birds shiver, they are able to activate particular muscle groups that work in opposition to one another. This causes muscle contractions that allow the birds to better retain their body heat.

All of the interaction between the several parts of the different systems in a bird’s anatomy only reinforces the certainty that birds did not evolve, but were instead created by a loving God who cares deeply for all of His creation, great and small.

“But now ask the beasts, and they will teach you; and the birds of the air, and they will tell you; or speak to the earth, and it will teach you. Who among all these does not know that the hand of the Lord has done this, in whose hand is the life of every living thing, and the breath of all mankind?” Job 12:7–10

Sources: reconnectwithnature.org (including Audubon Society, Smithsonian, Popular Science); Michael Stein for Bird Note

Nature – Creatures of the Air

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“Oh that I had wings like a dove! then I would fly away, and be at rest.” Psalm 55:6

In the domain of hawk, gull, and sparrow, physiology and aerial prowess are synonymous. A bird is simply a masterpiece of engineering – the perfect flying machine – supremely crafted by God and endowed with the attributes for a life in the skies. Its breast muscles, which operate its wings, are enormous, in some birds, comprising 33% of their total body weight. At the same time a bird’s skeletal system is incredibly light. The bones of a pelican, with a wingspan of nearly six feet, weigh only about five ounces, yet they are strong and flexible enough to withstand the constant stress of maneuverable flight.

Add to this package highly efficient digestive and respiratory systems, a large and powerful heart, and feathers that streamline, insulate, and provide the necessary lift for wings and tail, and it is easy to understand how Solomon could describe a bird in the air as a sight “too wonderful for me” (Proverbs 30:18, 19).

The methods and techniques of flight generally fall into a few basic categories. Flapping or power flight involves a strong downward stroke that results in rapid lift and forward thrust. Generally, the larger the bird the slower it flaps its wings. In contrast, the hummingbird will beat its wings up to 80 times a second while performing what has been called the most versatile display of aerial skill in all of God’s creation. The tiny bird can hover or fly in all directions – forward, backward, or to the side, depending upon its needs. Its rigid wings move in a unique figure 8 motion, powered by exceptionally strong muscles and a flexible swivel joint at its shoulder. The tail works as a rudder controlling the direction of movement. Not surprisingly, the hummingbird expends tremendous amounts of energy and to survive, must consume twice its body weight in food every day.

Gliding and soaring are far less demanding forms of flight, yet once again, the elements of aeronautical design are clearly seen. Fulmars slope soar, riding on air deflected upward from cliffs as its wings work in harmony with the surrounding wind currents, while a heron spreads its enormous wings in a slow approach to its nest. Large primary feathers at the end of each wing offer precise control of both speed and direction. A similar design enables a condor to ride for hours on spirals of warm air. Again, a huge wing surface allows for effortless gliding as the bird of prey searches the valley floor for food.

But for all the soaring wonder and power that so abundantly fills the skies, perhaps the supreme testimony to the Creator’s gifts of flight and life itself is written on the tissue-thin wings of the Monarch butterfly. Its wings are driven by powerful muscles designed into the insect’s upper body, the thorax, essential for migration. Advancing steadily, they ride on rising columns of warm air that can elevate them thousands of feet. These expert gliders can travel more than 50 miles a day flying upwards of 3,000 miles to reach their winter home.

God reveals Himself to man through the things He has made. Each day in the wonders of land, sky, and sea, He presents us with a vivid picture of His existence and character. It is a continuing revelation, as exciting and diverse as the creatures He has brought into being. In the majestic grace of a bird or butterfly in flight, an eternal truth shines clear – the God of all creation is real and alive, His power and wisdom are without limit and He cares and provides abundantly for the life that He has made.

Wonders of God’s Creation, Animal Kingdom: Great Are Thy Works, ©2004.

Nature Nugget – Feathered Jewels

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Hummingbirds, the second largest family of birds in the Western Hemisphere, are found from Patagonia at the southern tip of South America all the way north to Alaska. There are 338 species of hummingbirds, which range in size from the 2.5 inch Cuban Bee Hummingbird, the world’s smallest bird, to the 8.5 inch Giant Hummingbird of the Andes Mountains in South America. Not only are hummingbirds the smallest birds in the world, many weigh less than a penny, they are also among the most colorful and are often referred to as “feathered jewels.”

Hummers, as they are frequently called, are the only birds that can fly backwards. They can even fly upside down! Famous for their aerial acrobatics, they are capable of all flight maneuvers except soaring.

Hummingbirds can beat their wings up to an incredible 78 beats per second. Because of this, hummingbirds burn up energy very quickly. To supply their high energy needs, hummingbirds feed mainly on nectar from flowers and consume about 50 percent of their weight in sugar daily. They also feed on small invertebrates such as insects and spiders, which supply them with protein, minerals, vitamins, and fats. When flowers are scarce, they can survive for short periods of time on just invertebrates. Some have learned to feed on honeydew excreted by certain insects. Hummingbirds also visit sap wells created by sapsuckers on trees, feeding on the insects trapped there and possibly on the sugary sap as well.

Hummingbird bills come in a variety of shapes and sizes and are adapted to the particular feeding habits of each species. They can be straight or decurved or even curved upward and may be red, yellow, or black in color. Hummingbirds feed with their tongues, using a licking motion at a rate of about 13 licks per second. Their tongues are very long and can be greatly extended, if needed, when feeding.

The gaudy colors of hummingbirds are caused by two things: pigments and feather structure. The iridescent colors, such as red, green, and violet, are structural and are caused by light refraction or interference. Refraction is what causes rainbow colors when light passes through a prism. Interference is what causes the colors on thin films such as soap bubbles and oil slicks. These structural colors are especially represented in the hummingbird’s gorget and crown.

To get an idea of the incredible variety of jewel-like colors found on hummingbirds, consider their names: Ruby Topaz, Flame-rumped Sapphire, Sapphire-spangled Emerald, Garnet-throated Hummingbird, Brazilian Ruby, Jewelfront, Horned Sungem, and Purple-throated Mountain-gem, to name a few.

God’s word speaks of jewels. Solomon says, “. . . lips of knowledge are a precious jewel” (Proverbs 20:15) and “the lips of the wise disperse knowledge . . .” (Proverbs 15:7). In Proverbs 3:13–15 he speaks of wisdom and understanding as being better than silver and gold and more precious than rubies.

But how do we get wisdom, knowledge, and understanding? “The fear of the Lord is the beginning of wisdom: and the knowledge of the holy is understanding.” Proverbs 9:10. “. . . of Christ; In whom are hid all the treasures of wisdom and knowledge.” Colossians 2:2, 3. “If any of you lack wisdom, let him ask of God, . . . and it shall be given him. But let him ask in faith, nothing wavering.” James 1:5, 6. “So then faith cometh by hearing, and hearing by the word of God.” Romans 10:17.

Nature Nugget – Pelagic Tubenoses

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Tubenoses are a group of marine birds that spend the majority of their lives at sea, only coming to land to nest. Members of this group include the well known albatrosses and the lesser known shearwaters and petrels.

The name tubenose is derived from the presence of tubular nostrils running along the top of their bills. Their kidneys alone cannot filter out all the salt in the diet of these birds, so a pair of glands near the nasal passages in the front of the head helps secrete excess salt that would otherwise poison the system. The duct from each of the salt glands carries the salt solution into the nasal cavity where it is then discharged through the tubular nostrils where it drips off the tip of the bird’s bill. The system works only when excess salts accumulate, such as after feeding or drinking. The ability to drink seawater is a very important adaptation for being a sea bird. So adapted are they to their environment that they require salt water and will die of thirst when only fresh water is available.

Among the few birds with an acute sense of smell, tubenoses are attracted to oily scents from as far away as 30 km (19 miles). Tubenoses prey on marine animals with the larger species feeding on fish and squids and the smaller species on plankton. Most are scavengers and will commonly follow marine mammals, schools of large predatory fish, and even ships, feeding on scraps and refuse generated by their feeding and fishing activities.

Albatrosses and shearwaters have extremely long narrow wings. Their type of flight requires continuous winds. These winds, which do not carry them very high, give them enough lift over the waves to make a long wind-pushed glide until they descend to wave level, where they then turn into the wind and are again lifted like a kite for the next glide. Albatrosses, which have the longest wingspan of any bird, are the greatest gliders and can fly for hours without flapping their wings. The Wandering Albatross is the champion, with a wingspan of up to 12 feet.

Compared to albatrosses, shearwaters appear energetic, rapidly flapping and gliding over the sea, usually close to the surface. Shearwaters get their name because their pointed wings appear to slice the sea as they skim through troughs between ocean waves.

Ornithologists estimate that petrels are probably the most numerous birds in the world. Their flight is very energetic also, with rapid flapping followed by short glides. The Storm-Petrels appear to walk on water, as they tend to have their webbed feet extended downward to the water’s surface while picking small marine organisms from the surface during flight.

Just as the Lord has provided a way for the tubenoses to rid their bodies of the excess salts which would be toxic to them if not eliminated, so has He provided a way for us to rid our lives of sin which is toxic to us. “For the wages of sin [is] death; but the gift of God [is] eternal life through Jesus Christ our Lord.” Romans 6:23. “If we confess our sins, he is faithful and just to forgive us [our] sins, and to cleanse us from all unrighteousness.” 1 John 1:9. Praise God for the gift of His son!

Nature Nugget – Shorebirds Talents

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Shorebirds are a diverse avian group consisting of four families: plovers, avocets and stilts, oystercatchers, and sandpipers. Most North American shorebirds migrate over incredible distances from the arctic, where they breed, to coastal and interior wetland areas in South America, where they winter. Shorebirds need to eat up to one-third their body weight a day. Some can store fat reserves of up to 30 percent of their body’s weight in preparation for migration. Most shorebirds are closely associated with wetland areas where they feed on various shoreline habitats, mudflats, and marshes, in both fresh and saltwater environments.

Shorebirds have an amazing variety of bill shapes and sizes allowing them to feed in various habitats from dry soil to shallow water. Differences in bill length and shape and in leg length allow various species to flock together for protection without seriously competing with each other for food. These differences allow each species to find food at a different depth or location in the substrate. Some pick prey off the surface of the ground; others probe various depths underground, while others prey on aquatic creatures in the water and others on the surface of the water. Some feed at tideline, while others follow the waterline, and others feed in shallow water.

Plovers feed by picking, and have large eyes by which they locate their food. They feed above the waterline on wet to dry ground. Plovers are also known to use a technique called “foot patting” where the bird patters its feet on loose sand or mud, causing its prey to come to the surface. A well-known plover species in North America is the Killdeer, which is commonly found in pastures and farmland.

Oystercatchers have a long, triangular bill that is a cross between a knife and a chisel. They use it to stab into open bivalves, such as mussels and clams, severing the muscles that close the shell, or they smash open the shell if it is closed.

Avocets and Stilts have long legs and can feed in deeper water than most other shorebirds. Avocets have long, thin, upcurved bills, which they use as a scythe, sweeping it back and forth in the water stirring the bottom, and snatching up insects and crustaceans thus exposed.

The Sandpiper family constitutes the largest group of shorebirds. Body size, leg length, and bill size and shape are highly variable from one species to another. Sandpipers vary in size from the tiny 6-inch Least Sandpiper, which probes shallowly with its short bill, to the 23-inch Long-billed Curlew, which uses its long, decurved, forceps-like bill to probe deep into the burrows of marine worms. Two very odd members of this family are the Turnstones and Phalaropes. The Turnstones use their short upturned bills to flip over rocks and debris in search of food. Phalaropes gather their food in an ingenious way. They spin in circles on the surface of the water creating a whirlpool beneath them, which sucks up bottom dwelling insect larvae to the surface, where the Phalarope pick them off with their needle-like beaks.

Just as the Creator has given shorebirds a diversity of bill shapes and sizes and leg lengths, to allow them to exploit a variety of habitats and food sources, so He has provided mankind with a diversity of talents for use in His work. “To every person is committed some peculiar gift or talent which is to be used to advance the Redeemer’s kingdom.” Testimonies, vol. 4, 618. “In the Lord’s plan there is a diversity in the distribution of talents. . . . These talents are not bestowed capriciously, but according to the ability of the recipient.” Counsels on Stewardship, 116. “We must be always on the watch for opportunities to use for God the talents He has given us.” Testimonies, vol. 8, 27.

David Arbour writes from DeQueen, Arkansas.

Nature Nugget – Are Bluebirds Truly Blue?

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The light visible to our eyes is composed of many colors of light, each with its own distinct wave length. For example, red light has a long wavelength of around 700 nm, while blue light has a much shorter wavelength of around 400 nm. When light strikes an object, it either absorbs or reflects the various wavelengths. The particular wavelength or wavelengths reflected strike the retinas of our eyes and determines the color we perceive. When an object absorbs all wavelengths of light with none being reflected back, we perceive that object as being black. On the other hand, when an object reflects all wavelengths of light with none being absorbed, we perceive it as being white.

Most avian feather coloration is the result of different types of chemical compounds called pigments that are embedded in the feather during its development. The pigments absorb and reflect various wavelengths of light and thus determine the colors we see. The red of cardinals and the yellow of goldfinches are good examples of pigment color. Some species of birds, such as flamingoes, rely on carotinoids and other natural pigments obtained in their diet to maintain their color. When deprived of their natural diet of small planktonic crustaceans and algae, such as when they are kept in captivity, flamingoes lose their pink color and turn gray or dull buff, unless special formulas or artificial red dyes are added to their prepared food.

The blue coloration of most blue-colored birds such as bluebirds and white birds such as egrets is not from pigments but from structural coloration called schemochromes. This is a result of small changes in feather structure that alters their light reflective properties and results in a preferential scattering of light. Since blue light has a very short wavelength, it is selectively reflected more easily than other colors with longer wavelengths. If the red feather of a cardinal is ground to a powder, the color of the powder will be red due to the presence of red pigments. If you do the same thing with a blue feather from a bluebird, the powder will be dark instead of blue. Blue and green pigments are virtually unknown in birds except for the turaco family of Africa. The green coloration of most green birds is created by a combination of structural blue coloration and yellow carotinoid pigments in the feathers.

Iridescent colors, as seen in purple martins and grackles, is a physical phenomenon similar to structural blue color. Highly modified barbules on the feathers produce a differential reflection of wavelengths when they are rotated, so that a flat surface faces the incoming light. The structure of the barbules reflects some wavelengths of light and absorbs others, with the reflected wavelength changing with the angle of reflection. So as the bird moves around, the angle of reflection and wavelengths change, producing a change of color to the eye.

Blue is a very important color in the Bible, as it was chosen to represent the Ten Commandments. The color stands for truth and is where we get the term “true-blue.” The color blue was used in the sanctuary and was also worn as a ribbon of blue on the border fringes of the Israelites’ garments. This was a reminder for them to keep God’s Law. (See Numbers 15:38–40.) The color blue should still be important to us today as a reminder to keep God’s Ten Commandments! Even though a bluebird is truly not blue, the color we perceive from it is real and should remind us every time we see one that we are still obligated to keep God’s Law.

David Arbour writes from his home in DeQueen, Arkansas. He may be contacted by e-mail at: landmarks@stepstolife.org.

Nature Nugget – The Bird-watcher’s Lifelist

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There are approximately 9,730 species of birds worldwide, of which a little over 800 have been recorded in North America, north of Mexico. A few new species are still discovered every year in remote areas of the world, such as in the rainforests of South America and Southeast Asia. Birds are found literally everywhere on this planet, from smog-choked cities to remote wilderness areas, and from high, snow-covered mountains to open, high seas thousands of miles from land. Because of their beauty and easy accessibility (just step out into your backyard), birds have been an object of man’s interest since creation. Now, more than ever, due to the inventions of quality binoculars and spotting scopes, and identification field guides that now cover every region of the earth, watching birds has become very popular. Often all one has to do is see a Painted Bunting or a Purple Gallinule, and he or she is hooked!

Over 60 million Americans will grab their binoculars and field guides to do a bit of bird watching this year! Most only watch birds in their own backyard at bird feeders or while on vacation, but some regularly travel many miles to observe birds in different parts of their own states, country, or various countries of the world, and there are various degrees of interest and participation between these extremes.

Bird watching or “birding,” as many prefer to call it, is often considered a sport, and is now the single most popular hobby on the North American continent. In Great Britain, the term “bird-watcher” is preferred over “birder,” and the term “twitcher” is used for the serious “bird-watcher.” The term “twitcher” was coined to describe the uncontrollable spasms of excitement the “bird-watcher” exhibits when seeing a new bird for the first time.

Most “birders,” as the more serious prefer to call themselves, keep lists of the birds they see in various places. They keep lists of species seen in their country, state, county, and yards. They keep day lists and trip lists. Some keep lists for other states and countries they visit. The most important list for the serious birder is his Lifelist. The Lifelist is a running list kept of all new species encountered that one has never seen before. When a “birder” encounters a “Lifer,” as new species are called, he records in a log book its name, date seen, and location. For instance, my last “Lifer” was a Cocoa Woodcreeper seen on February 3, 2004, at Lancetilla Botanical Gardens near Tela, Honduras. In Great Britain, the adding of a species to one’s list is called “ticking.” It is quite a sight to see a “twitcher” in the act of “ticking”!

Heaven keeps a “Lifelist” also. It is not a list of birds, but rather a list of souls that have surrendered their lives to Christ. “The names of all those who have once given themselves to God are written in the book of life, and their characters are now passing in review before Him. Angels of God are weighing moral worth. They are watching the development of character in those now living, to see if their names can be retained in the book of life.” “Ellen G. White Comments,” Seventh-day Adventist Bible Commentary, vol. 7, 960. “All who persevere in obedience, all who will not sell their souls for money or for the favor of men, God will register in the book of life.” Ibid., 950.

“Glorious will be the deliverance of those who have patiently waited for His coming and whose names are written in the book of life.” The Great Controversy, 634.

David Arbour writes from his home in DeQueen, Arkansas. He may be contacted by e-mail at: landmarks@stepstolife.org.

Nature Nugget – Dove Invasion

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The Eurasian Collared-Dove is a medium-sized, pale grayish-brown dove with a black collar on the back of the neck. It was originally native to the Indian subcontinent with a slight extension over to Turkey. During the sixteenth century, the Collared-Dove spread through Asia Minor and the Balkans. Recently, it has undergone an explosive range expansion throughout Europe and most of North America.

Over a 44-year period during the past century, the Collared-Dove expanded its range westward by 1,800 miles, covering most of Europe at an average rate of 41 miles per year. They now occur as far north as Iceland and above the Arctic Circle in Norway. Colonization occurred in jumps of several hundred miles at a time with subsequent back filling. It is currently still expanding its range into Russia and the Iberian Peninsula.

During the early 1970s, an order was placed to Great Britain from the Bahamas for some Ringed Turtle-Doves, a similar looking domesticated relative of the Collared-Dove. Unable to fill this order, the supplier sent Eurasian Collared-Doves instead. In 1974, as the result of an aviary break-in, about 50 of these birds were released into the wild. Over the next ten years, their population reached around 10,000 birds, and they started spreading to other islands. By the mid-1980s, they reached Miami, Florida, on the North American mainland. From there, their colonization of North America has been very rapid. Now, almost 20 years later, they currently have an almost continuous population extending from Florida north to Indiana and west through the Great Plains. They are still spreading north and west, and there are now records of sightings as far away as Minnesota, Washington, and Nevada. There is a separate introduced population in coastal southern California that is starting to spread also.

Fortunately, the Eurasian Collared-Dove does not seem to be competing with the native North American doves but seems to be occupying an empty ecological niche in our environment created by man. They prefer suburban areas of towns and cities where they frequent bird feeders and ornamental plantings found in people’s yards. They feed on agricultural grains, leaves, fruits, and seeds. They also occur in the country around farms with grain bins.

“Have you ever watched a hawk in pursuit of a timid dove? Instinct has taught the dove that in order for the hawk to seize his prey, he must gain a loftier flight than his victim. So she rises higher and still higher in the blue dome of heaven, ever pursued by the hawk, which is seeking to obtain the advantage. But in vain. The dove is safe as long as she allows nothing to stop her in her flight, or draw her earthward; but let her once falter, and take a lower flight, and her watchful enemy will swoop down upon his victim. . . .

“We have before us a warfare,—a lifelong conflict with Satan and his seductive temptations. The enemy will use every argument, every deception, to entangle the soul; and in order to win the crown of life, we must put forth earnest, persevering effort. We must not lay off the armor or leave the battlefield until we have gained the victory, and can triumph in our Redeemer. As long as we continue to keep our eyes fixed upon the Author and Finisher of our faith, we shall be safe. But our affections must be placed upon things above, not on things of the earth. By faith we must rise higher and still higher in the attainment of the graces of Christ. By daily contemplating His matchless charms, we must grow more and more into His glorious image. While we thus live in communion with Heaven, Satan will lay his nets for us in vain.” The Youth’s Instructor, May 12, 1898.

David Arbour writes from his home in DeQueen, Arkansas. He may be contacted by e-mail at: landmarks@stepstolife.org.

Nature Nugget – Brood Parasitism

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About one percent of the 9,000 plus bird species on this planet does not construct nests and raise their own young. These birds pawn this job off onto birds of other species. They do this by laying their eggs in other birds’ nests, letting them do the incubating and rearing for them.

In North America, the three species of cowbirds are well known for this behavior. Bronzed Cowbirds are found in the southwestern United States and along the Gulf Coast as far east as Louisiana. The Shiny Cowbird is native to the Caribbean area and is currently expanding its range through Florida and along the Gulf Coast as far west as Texas. The Brown-headed Cowbird is found throughout the United States and most of Canada. It is known to parasitize the nests of more than 200 bird species and lay up to 40 eggs per year.

When a cowbird parasitizes a nest, it removes one of the host species’ eggs and replaces it with one of its own eggs. The cowbird egg has a shorter incubation period, which means it will usually hatch before the other eggs do. The cowbird young also grows faster than the host species’ young and will dominate the food brought to the nest. If there is a plentiful supply of food, all the young will survive. If not, only the cowbird young will survive.

Brown-headed Cowbirds are birds of open country, preferring to feed around livestock. In spite of being an open country bird, they will penetrate dense forested areas a short distance to lay their eggs in the nests of birds living there. But woodland birds living deep in the forests far from open areas are safe from the cowbirds. Before the settling of North America, the eastern part of this country was heavily forested, and the Brown-headed Cowbirds were found only on the Great Plains where they followed buffalo herds around and were not very common.

Most species of birds that occurred with the cowbirds on the Great Plains were used to the cowbirds parasitizing their nests and were not easily fooled by a strange egg showing up in the nest. They would usually respond by either abandoning the nest, removing the cowbird’s egg, or building a new nest layer over the top of the cowbird egg. Enough birds were fooled to keep a small population of cowbirds surviving.

With the settling of eastern North America, the vast forests were opened up and fragmented for farming and livestock. This allowed the cowbird to invade the area, where it quickly adapted to feeding around livestock in place of buffalo. The eastern forest birds in this area were not used to the cowbird’s nest parasitism and were easily fooled by them, resulting in a population explosion for the cowbirds and a decrease in the host species populations. Only the birds that lived deep in the few large, unfragmented-forested areas left were safe from the cowbirds. Most of the eastern host species are slowly adapting to the cowbirds, but a few species are not and are threatened or endangered because of habitat loss and cowbird brood parasitism.

Just as the only birds that are safe from the cowbird’s attack are the ones living deep in the forests out of their reach, so the only people who are safe from Satan’s attacks are those who dwell in the arms of Jesus. “Dangers and perils surround us; and we are only safe when we feel our weakness and cling with the grasp of faith to our mighty Deliverer.” Testimonies, vol. 3, 473. “Our only safety is in keeping fast hold of Jesus. Never are we to lose sight of Him.” Selected Messages, Book 2, 59.

David Arbour writes from his home in DeQueen, Arkansas. He may be contacted by e-mail at: landmarks@stepstolife.org.