Collectively called waders, six kinds of large, long-legged birds illustrate convergence; life from different backgrounds shaped by the habitat they live in so they are similar in some characteristics and habits. The six species are great blue herons, great egrets, glossy ibises, wood storks, roseate spoonbills and sandhill cranes. They all have long legs, necks and beaks for getting food. Although each one of these species has its own particular niche, there is overlap among all of them. There is some competition for food. These birds nest in colonies in trees, sometimes in pure groups, but most often in mixed gatherings of at least a few species. Field guides to birds are helpful in identifying these large birds.
Great blue herons and great egrets are in the heron family and have lenghty legs for wading in water. Both these common and wide spread species in North America consume fish, frogs, tadpoles, crayfish and other aquatic creatures. But they also catch and eat snakes, larger insects and field mice in meadows near ponds and creeks. When they catch mice, they dunk their victims in water to slick the fur so they can swallow them easier. Herons fly with their legs stretched out the back, but curved-back necks.
Ibis are related to herons and have similar features, except ibis beaks are curved down to grab prey at different angles than their cousins, perhaps reducing competition with them for the same prey. They fly with necks and legs stretched out.
Wood storks have bare heads and necks, a distinguishing characteristic. They are North America's only stork, living uncommonly in the southeastern part of the United States, but also in South America. They can catch larger prey from the water, swamps and meadows than can the other species noted here because they have larger, thicker, therefore, more powerful beaks. That would reduce rivalry with other waders for food. Wood storks fly with legs and necks extended beyond their bodies and often soar high in the sky.
Roseate spoonbills are also not common in the southeastern United States, but are more common in South America. They are, in fact, the only spoonbills in the western hemisphere. They have bills that are flattened at the tips like paddles. They work their beaks sideways in shallow water and soft mud, all the while opening and closing them, to gather tadpoles, aquatic insect larvae, shrimp, small fish and other small, aquatic critters in ponds and marshes along shorelines and mudflats.
Sandhill cranes are the most terrestrial of all these bird species, but they, too, get some food from shallow water. Sandhills migrate in great flocks, mostly over the prairies and farms of the American mid-west. One of their resting areas on migration is the shallows and flats of the Platte River in Nebraska. This type of bird eats seeds, including corn, but also berries, roots, snakes, mice, insects, frogs and crayfish. In flight, their necks and legs are extended and they often soar in great gatherings of themselves. They have a deep, rolling call when in flight that helps identify them.
These are a few big, long-legged, lengthy-necked birds in the United States that overlap each others habitats, yet have their own niches. Each species is interesting in its own way, adding more enjoyment to the outdoors.
Monday, August 31, 2015
Favorite Feathered Neighbors
Two species of adaptable birds, Carolina chickadees and blue jays, have been my favorite feathered neighbors in our suburban neighborhood for many years for a variety of reasons. And, as I sat in front of our computer about to type this true story, a chickadee fluttered a couple of minutes among twigs of a lilac bush, just outside the window I'm facing, only four feet from my face, as if encouraging me to get on with it and tell its story. What a coincidence! Or was it?
As species, Carolina chickadees and blue jays are woodland birds that have adapted to suburban areas with their many trees and shrubbery, adding another touch of wildness to those suburbs. Happily, both these species of birds are permanent residents in our yard, as many populations of their kinds are throughout much of North America. There has been at least one pair of each species here, continuously and the year around for many years, as long as I have lived here. Each species raises young in our neighborhood and they come to our feeder when we provide bird feed during winter. I never tire of seeing and hearing them among the trees and shrubbery around the house. They are always interesting.
Both these species of birds are attractive. The chicks are smaller than sparrows, mostly gray, but with a jaunty black cap and bib. Their greatest beauty, however, is their lively, seemingly cheerful actions no matter the weather is the year around, accompanied by their "dee-dee" or "chick-a-dee-dee-dee" notes through the year.
Blue jays are mostly blue, with black and white markings. They have a crest on top of their heads and often a raucous calling, including a raspy "jay, jay". They can be brash at times, like their crow relatives, but quiet while raising young, so as to not draw attention to themselves and their offspring. Chickadees hatch youngsters in cavities, including those in trees, abandoned woodpecker holes and erected wren or bluebird boxes. Each female lays about 6 eggs in a clutch. Some summers, the pair of chicks in our neighborhood have reared young in boxes we erected. But, apparently, they hatch youngsters somewhere else in the neighborhood during other years. And, throughout the year, a pair of chicks also enters a dryer vent not used anymore on our house.
A couple places that blue jays have nested on our lawn are high in one of our Norway spruce trees and on top of a eight-foot-tall red juniper tree. I only know they have reared offspring high in a spruce by watching their constant comings and goings in that tree for a few weeks in summer. And I have watched the parents feeding the newly fledged young in our yard. I noticed the jay nursery in the juniper by innocently walking by it one day. An unseen jay jumped out of that juniper and began calling raucously as I walked by. I looked up and saw the cradle at the top of that young tree.
Some years I see the courting of blue jays in our neighborhood. The pair is inseparable and the male offers tidbits of food to his mate. And they engage in much pleasant "conversation".
Chickadees and jays, being dramatically different sized birds, do not compete much for food. The chicks eat invertebrates and their tiny eggs, and small seeds and berries. Jays consume invertebrates, small acorns, like those on pin oaks, corn, seeds and berries. In fall, I see the attractive jays gathering pin oak acorns from among strikingly golden or orange pin oak leaves to bury in the ground or push into tree cavities. The jays will consume some of those hidden acorns in winter when food is scarce. Both species enjoy ingesting sunflower seeds and other grains at bird feeders.
The adaptable Carolina chickadees and blue jays add much beauty and wildness to the tree and bush-studded lawns they live in. They are pleasant and helpful neighbors to have, being attractive, lively and cheery, and eating many insects and weed seeds.
As species, Carolina chickadees and blue jays are woodland birds that have adapted to suburban areas with their many trees and shrubbery, adding another touch of wildness to those suburbs. Happily, both these species of birds are permanent residents in our yard, as many populations of their kinds are throughout much of North America. There has been at least one pair of each species here, continuously and the year around for many years, as long as I have lived here. Each species raises young in our neighborhood and they come to our feeder when we provide bird feed during winter. I never tire of seeing and hearing them among the trees and shrubbery around the house. They are always interesting.
Both these species of birds are attractive. The chicks are smaller than sparrows, mostly gray, but with a jaunty black cap and bib. Their greatest beauty, however, is their lively, seemingly cheerful actions no matter the weather is the year around, accompanied by their "dee-dee" or "chick-a-dee-dee-dee" notes through the year.
Blue jays are mostly blue, with black and white markings. They have a crest on top of their heads and often a raucous calling, including a raspy "jay, jay". They can be brash at times, like their crow relatives, but quiet while raising young, so as to not draw attention to themselves and their offspring. Chickadees hatch youngsters in cavities, including those in trees, abandoned woodpecker holes and erected wren or bluebird boxes. Each female lays about 6 eggs in a clutch. Some summers, the pair of chicks in our neighborhood have reared young in boxes we erected. But, apparently, they hatch youngsters somewhere else in the neighborhood during other years. And, throughout the year, a pair of chicks also enters a dryer vent not used anymore on our house.
A couple places that blue jays have nested on our lawn are high in one of our Norway spruce trees and on top of a eight-foot-tall red juniper tree. I only know they have reared offspring high in a spruce by watching their constant comings and goings in that tree for a few weeks in summer. And I have watched the parents feeding the newly fledged young in our yard. I noticed the jay nursery in the juniper by innocently walking by it one day. An unseen jay jumped out of that juniper and began calling raucously as I walked by. I looked up and saw the cradle at the top of that young tree.
Some years I see the courting of blue jays in our neighborhood. The pair is inseparable and the male offers tidbits of food to his mate. And they engage in much pleasant "conversation".
Chickadees and jays, being dramatically different sized birds, do not compete much for food. The chicks eat invertebrates and their tiny eggs, and small seeds and berries. Jays consume invertebrates, small acorns, like those on pin oaks, corn, seeds and berries. In fall, I see the attractive jays gathering pin oak acorns from among strikingly golden or orange pin oak leaves to bury in the ground or push into tree cavities. The jays will consume some of those hidden acorns in winter when food is scarce. Both species enjoy ingesting sunflower seeds and other grains at bird feeders.
The adaptable Carolina chickadees and blue jays add much beauty and wildness to the tree and bush-studded lawns they live in. They are pleasant and helpful neighbors to have, being attractive, lively and cheery, and eating many insects and weed seeds.
Friday, August 28, 2015
Life Generally Overlooked
On the afternoon of August 25, 2015, I stopped at a tiny shallow tributary of Mill Creek in a sunny meadow about a mile south of New Holland, Pennsylvania to see what wildlife was visible. This little trib of clear water also receives cleaned-up waste water from a food processing plant, which might make that waterway more of a challenge for wildlife to live in. But over the years, I have seen a variety of aquatic plants and creatures thriving in it and that day in August was no exception.
That little brook seemed devoid of animal life when I first arrived, but I knew better than to give up. Within seconds I saw schools of light-brown banded killifish, a minnow-like species, in the inches-deep, clear waterway. Actually, I saw their dark shadows on the muddy bottom of the stream before the fish themselves because they were camouflaged brown above brown, which protects them from herons, kingfishers and other predators on fish. These small fish are also vertically striped, which helps them blend into their austere surroundings
Killifish are long, and thin, streamlined for life in a waterway's current. They are adapted to warmer waters with mud bottoms. They feed on bits of plant and animal debris and small invertebrates in the water and on its surface. And these particular killifish prove that the waste water from the plant is cleansed before it is released into Mill Creek.
By scanning my 16 power binoculars along the tiny, mud shores of the waterway and the grass, sedges and blooming arrowhead plants growing from the shallow water, I saw several male bluet damselflies, singly and in gatherings of several per group. Since I couldn't see their transparent wings, they looked like one-and-a-half long, horizontal blue streaks with black rings perched on the waterside vegetation or hovering like tiny, blue helicopters low over the water. And each one of a few males held a pale-gray female behind her head by the tip of his long, thin abdomen in a spawning embrace as each female deposited eggs in the shallows. There probably were several more female damselflies along that little brook, but being gray and small, they were difficult to see for their own safety. I didn't notice many of them.
In many species of wildlife, males are show-offs with bright colors or sounds to attract females to them for mating, and to intimidate other males into getting out of their breeding areas. And the attractive male bluet damselflies are blue and black-marked for that reason.
The resulting damselfly nymphs from the spawning are thin, brown, and predatory on tiny invertebrates on the muddy bottom of this tributary of Mill Creek. But within a year, those nymphs change to adults with wings, crawl out of the water and look for flying insects to eat and mates.
Several least skippers, a kind of small butterfly, flitted among the grasses and sedges growing on the muddy edges of this little waterway. Their pretty wings were pale-yellow, edged with brown. The ones I saw might have been females ready to lay eggs on the grasses and sedges, their young 's only food.
Several sulphur yellow butterflies puddled in the mud on the shore of this brook. Usually sipping nectar from flowers, as most butterflies do, this species of butterfly, as with many of their kin, get water, salt and minerals from mud, wherever it may be.
No matter how small or seemingly insignificant a species may seem, all life is beautiful and important. All habitats, including human-made ones, no matter how small, harbor interesting life. Some of the most intriguing life is generally overlooked.
That little brook seemed devoid of animal life when I first arrived, but I knew better than to give up. Within seconds I saw schools of light-brown banded killifish, a minnow-like species, in the inches-deep, clear waterway. Actually, I saw their dark shadows on the muddy bottom of the stream before the fish themselves because they were camouflaged brown above brown, which protects them from herons, kingfishers and other predators on fish. These small fish are also vertically striped, which helps them blend into their austere surroundings
Killifish are long, and thin, streamlined for life in a waterway's current. They are adapted to warmer waters with mud bottoms. They feed on bits of plant and animal debris and small invertebrates in the water and on its surface. And these particular killifish prove that the waste water from the plant is cleansed before it is released into Mill Creek.
By scanning my 16 power binoculars along the tiny, mud shores of the waterway and the grass, sedges and blooming arrowhead plants growing from the shallow water, I saw several male bluet damselflies, singly and in gatherings of several per group. Since I couldn't see their transparent wings, they looked like one-and-a-half long, horizontal blue streaks with black rings perched on the waterside vegetation or hovering like tiny, blue helicopters low over the water. And each one of a few males held a pale-gray female behind her head by the tip of his long, thin abdomen in a spawning embrace as each female deposited eggs in the shallows. There probably were several more female damselflies along that little brook, but being gray and small, they were difficult to see for their own safety. I didn't notice many of them.
In many species of wildlife, males are show-offs with bright colors or sounds to attract females to them for mating, and to intimidate other males into getting out of their breeding areas. And the attractive male bluet damselflies are blue and black-marked for that reason.
The resulting damselfly nymphs from the spawning are thin, brown, and predatory on tiny invertebrates on the muddy bottom of this tributary of Mill Creek. But within a year, those nymphs change to adults with wings, crawl out of the water and look for flying insects to eat and mates.
Several least skippers, a kind of small butterfly, flitted among the grasses and sedges growing on the muddy edges of this little waterway. Their pretty wings were pale-yellow, edged with brown. The ones I saw might have been females ready to lay eggs on the grasses and sedges, their young 's only food.
Several sulphur yellow butterflies puddled in the mud on the shore of this brook. Usually sipping nectar from flowers, as most butterflies do, this species of butterfly, as with many of their kin, get water, salt and minerals from mud, wherever it may be.
No matter how small or seemingly insignificant a species may seem, all life is beautiful and important. All habitats, including human-made ones, no matter how small, harbor interesting life. Some of the most intriguing life is generally overlooked.
Wednesday, August 26, 2015
Migrant Raptors in August
The migrations of southbound, diurnal raptors (hawks and eagles) begins in August each year. And ospreys, bald eagles, broad-winged hawks, sharp-shinned hawks, red-tailed hawks and American kestrels are the most common migrants during August, the first month of southbound raptor passages. We know that because people staff rocky look-outs on mountain tops along some of the Appalachian Mountains in Pennsylvania, West Virginia and other states the Appalachians pass through. A few of those watches on mountains in Pennsylvania that come to mind include Hawk Mountain Sanctuary, Bake Oven, Waggoner's Gap and Second Mountain.
People staff those lookouts from the beginning of August through December every year to learn what raptors are coming through this area during their fall migrations, how many there are, whether their populations are increasing or decreasing, and what are their flight patterns in different weather and wind direction circumstances.
Generally, when the wind comes from the northwest or north, it pushes up and over the southwest running Appalachians, pushing the hawks and eagles up with it. Gravity wants to pull the raptors down, so by setting their wings just right, the raptors can soar ahead for many miles with little effort. But when wind comes from the other directions, the raptors don't get the lift they need from the mountains, so they scatter off them and across flat land. Then those hawks and eagles can be spotted most any place.
Ospreys and bald eagles are big and majestic on the wing, causing excitement among many people, as they pass anywhere over Pennsylvania on their way south for the winter. And both of those species can be spotted around larger bodies of water as they watch for bigger fish to catch and eat before going farther south. Their migrations, as species, continue during September and October.
Broad-winged hawks are unique among raptors in the eastern United States in that they migrate south in flocks, often large gatherings of hundreds. Broadies are exciting to see flying and soaring out of the woods they spent the night in and seeking thermals, which are columns of sun-warmed air rising up into the sky. When broad-wings find a thermal, they enter it and it spirals them high into the sky, again with little effort, until they are almost out of sight. When they have gone as high as they can, the broadies peel out of the thermal, by the dozens, scores or hundreds, and head southwest in long lines or sheets of themselves. But gravity pulls them down, bit by bit, and so they are obliged to find another thermal and another, all day, every day of their migration south to Central and northern South America where they spend the northern winter. Broad-wings migrate out of the eastern United States during August and September, with a peak of exodus around September 20th. By the end of September, they have all left this part of North America.
Broad-wings raise young in eastern North American forests and feed them frogs, mice, small birds, larger insects and so on. Because they ingest so many small, cold-blooded critters that aren't available in winter, broadies must winter in the tropics to get food. In fact, birds in general, migrate not to escape winter's cold, but to find reliable sources of food through that harshest of seasons.
The small, stream-lined sharp-shinned hawks, the large, soaring red-tailed hawks and those diminutive falcons, the American kestrels, all migrate through Pennsylvania in good numbers during August and September. Sharp-shins also pass through here during October and red-tails during November and into December. Sharpies prey mostly on small birds, while red-tails and kestrels mostly catch mice, and other rodents in the case of the red-tails.
Red-tails are also stately on the wing, and exciting when many are seen migrating south, one after another, in almost a steady stream. This species is especially appealing on migration in the chilling, thrilling winds of October, November and into December.
Some kestrels pass through here and continue farther south. But others spend the winter here, mostly catching mice and small birds in fields and along roadsides and hedgerows.
This fall, or succeeding ones, watch for migrating diurnal raptors, starting in August. They are handsome, and thrilling riding the winds or thermals to their wintering grounds.
People staff those lookouts from the beginning of August through December every year to learn what raptors are coming through this area during their fall migrations, how many there are, whether their populations are increasing or decreasing, and what are their flight patterns in different weather and wind direction circumstances.
Generally, when the wind comes from the northwest or north, it pushes up and over the southwest running Appalachians, pushing the hawks and eagles up with it. Gravity wants to pull the raptors down, so by setting their wings just right, the raptors can soar ahead for many miles with little effort. But when wind comes from the other directions, the raptors don't get the lift they need from the mountains, so they scatter off them and across flat land. Then those hawks and eagles can be spotted most any place.
Ospreys and bald eagles are big and majestic on the wing, causing excitement among many people, as they pass anywhere over Pennsylvania on their way south for the winter. And both of those species can be spotted around larger bodies of water as they watch for bigger fish to catch and eat before going farther south. Their migrations, as species, continue during September and October.
Broad-winged hawks are unique among raptors in the eastern United States in that they migrate south in flocks, often large gatherings of hundreds. Broadies are exciting to see flying and soaring out of the woods they spent the night in and seeking thermals, which are columns of sun-warmed air rising up into the sky. When broad-wings find a thermal, they enter it and it spirals them high into the sky, again with little effort, until they are almost out of sight. When they have gone as high as they can, the broadies peel out of the thermal, by the dozens, scores or hundreds, and head southwest in long lines or sheets of themselves. But gravity pulls them down, bit by bit, and so they are obliged to find another thermal and another, all day, every day of their migration south to Central and northern South America where they spend the northern winter. Broad-wings migrate out of the eastern United States during August and September, with a peak of exodus around September 20th. By the end of September, they have all left this part of North America.
Broad-wings raise young in eastern North American forests and feed them frogs, mice, small birds, larger insects and so on. Because they ingest so many small, cold-blooded critters that aren't available in winter, broadies must winter in the tropics to get food. In fact, birds in general, migrate not to escape winter's cold, but to find reliable sources of food through that harshest of seasons.
The small, stream-lined sharp-shinned hawks, the large, soaring red-tailed hawks and those diminutive falcons, the American kestrels, all migrate through Pennsylvania in good numbers during August and September. Sharp-shins also pass through here during October and red-tails during November and into December. Sharpies prey mostly on small birds, while red-tails and kestrels mostly catch mice, and other rodents in the case of the red-tails.
Red-tails are also stately on the wing, and exciting when many are seen migrating south, one after another, in almost a steady stream. This species is especially appealing on migration in the chilling, thrilling winds of October, November and into December.
Some kestrels pass through here and continue farther south. But others spend the winter here, mostly catching mice and small birds in fields and along roadsides and hedgerows.
This fall, or succeeding ones, watch for migrating diurnal raptors, starting in August. They are handsome, and thrilling riding the winds or thermals to their wintering grounds.
Jewelweeds
Two species of jewelweeds, spotted and pale, are native to much of the eastern United States, including in southeastern Pennsylvania. Both these closely related, annual plants sprout in moist, mostly shaded soil in April, including in damp woods and along shaded roadside ditches, and reach full size of up to five feet tall and shrub-like by mid-August. They start blooming toward the end of August, reaching the peak of their blossoming early in September.
These jewelweed species have similar leaves in shape and shade of green. But spotted jewelweeds have orange flowers, spotted with red. Pale jewelweed blooms are pale yellow. And the blossoms of both species hang like pendant jewelry and ear rings, hence their common name.
Spotted jewelweeds are more likely to grow and bloom in bushy stands where there is a good bit of sunlight each day, while pale jewelweeds most often flower in shaded areas. However, I sometimes see mixed patches of these two species with their orange and yellow flowers forming wild bouquets of themselves in mostly shaded areas.
Migrating ruby throated hummingbirds, heading south to South and Central America to avoid the northern winter, poke their long beaks into jewelweed flowers to sip sugary nectar. And worker bumble bees and a variety of other insects do so as well, pollinating the blooms in the process.
Both species of jewelweeds are also called "touch-me-nots", but that is a misnomer. When the seeds in jewelweed pods are ripe by late autumn, the pods will snap open at the slightest touch, popping the seeds a few feet from the parent plants. Obviously, it is to the plants' best interests to have their ripened pods touched to spread their seeds onto soil where jewelweeds are not yet growing. People, as well as deer, foxes, birds and other creatures, moving through jewelweed thickets brush against the pods, which releases their seeds. Mice and small birds eat some of those seeds through winter. The surviving seeds sprout the next spring.
It's always an interesting experience to touch a jewelweed pod with a finger tip and watch it project its seeds. A coiled bit of vegetation in each pod twists abruptly like a coiled spring snapping, tearing open the pod with great force for something so small.
Jewelweed stems ooze juice when injured. That liquid, when applied to bare human skin, relieves the burning of stinging nettle chemicals, the irritation of poison ivy and the stings of bees.
Jewelweeds have attractive flowers and practical purposes to wildlife and people. Small wildlife consume their nectar or seeds, and we get relief from burning and itching on our skin. Look for these bushy annuals, and their lovely flowers, in damp, shaded areas from now to about the middle of September.
These jewelweed species have similar leaves in shape and shade of green. But spotted jewelweeds have orange flowers, spotted with red. Pale jewelweed blooms are pale yellow. And the blossoms of both species hang like pendant jewelry and ear rings, hence their common name.
Spotted jewelweeds are more likely to grow and bloom in bushy stands where there is a good bit of sunlight each day, while pale jewelweeds most often flower in shaded areas. However, I sometimes see mixed patches of these two species with their orange and yellow flowers forming wild bouquets of themselves in mostly shaded areas.
Migrating ruby throated hummingbirds, heading south to South and Central America to avoid the northern winter, poke their long beaks into jewelweed flowers to sip sugary nectar. And worker bumble bees and a variety of other insects do so as well, pollinating the blooms in the process.
Both species of jewelweeds are also called "touch-me-nots", but that is a misnomer. When the seeds in jewelweed pods are ripe by late autumn, the pods will snap open at the slightest touch, popping the seeds a few feet from the parent plants. Obviously, it is to the plants' best interests to have their ripened pods touched to spread their seeds onto soil where jewelweeds are not yet growing. People, as well as deer, foxes, birds and other creatures, moving through jewelweed thickets brush against the pods, which releases their seeds. Mice and small birds eat some of those seeds through winter. The surviving seeds sprout the next spring.
It's always an interesting experience to touch a jewelweed pod with a finger tip and watch it project its seeds. A coiled bit of vegetation in each pod twists abruptly like a coiled spring snapping, tearing open the pod with great force for something so small.
Jewelweed stems ooze juice when injured. That liquid, when applied to bare human skin, relieves the burning of stinging nettle chemicals, the irritation of poison ivy and the stings of bees.
Jewelweeds have attractive flowers and practical purposes to wildlife and people. Small wildlife consume their nectar or seeds, and we get relief from burning and itching on our skin. Look for these bushy annuals, and their lovely flowers, in damp, shaded areas from now to about the middle of September.
Monday, August 24, 2015
A Few Insects on our Lawn
During the last several days, starting about the 18th of August, I noticed a few kinds of interesting and attractive insects on our lawn. I've seen these species of insects before in our yard, but not so abundantly as now.
We have a large vine of deadly nightshade on a planted viburnum bush. Right now that vine has several purple-petaled flowers with yellow stamens protruding beyond the petals, and green, yellow, orange and red berries. The different colored berries indicate they don't all ripen at once. And part of the attraction of this nightshade vine are the many furry, black and yellow bumble bees that visit the blooms to sip nectar and collect pollen. These are sterile, female, worker bees that take nectar and pollen from the blossoms to feed their younger, larval sisters in their nests in clumps of grass in the ground, while the mother of them all, the queen, continues to lay eggs in that grassy home in the soil.
Meanwhile that day, I saw several digger wasps feeding on nectar in clumps of tiny, pale lavender spearmint flowers. Digger wasps are three-quarters of an inch long with a one inch wing span. They are black with deep-orange abdomens.
Adult digger wasps visit flowers to sip sugary nectar and females dig in the soil to find the larvae of green June beetles, which live under ground in our yard. Female digger wasps sting each larva they find to paralyze it and lay an egg on top of it. The resulting wasp larva eats the June beetle larva, pupates in the ground through winter and emerges the next summer, ready to feed on flower nectar and reproduce themselves.
But the most intriguing of these interesting insects in our yard are the cicada killers that are in our neighborhood in abundance. There is a colony of female cicada killers that worked together in a patch of clay soil with sparse vegetation to dig out several branching burrows in the soil, each one with a few cells at the end. Each female digs with her front legs and kicks out the soil with her rear ones.
Meanwhile, we have annual cicadas all over our lawn. They had been brown grubs sucking sap from tree roots for at least one year. Then they dug out of the ground during some nights in August, leaving quarter-inch holes in the soil, and climbed trees, shrubs and other objects. After a while, the back of the exoskeleton, or shell, splits open on each grub and the adult cicada, complete with wings and horny plates under their abdomens on the males, emerged. After several days, many empty shells still cling to the objects the grubs climbed up.
The next day, and for several days after, the cicadas fly about in the trees looking for mates. Males vibrate the flaps on their abdomens to make the buzzing, whirring sounds we hear during the day and early evening to attract females to them for breeding.
I see both the chunky, dark cicadas and large, yellowish-orange cicada killers zip about among the trees and bushes. The cicadas are finding mates, but the female cicada killers are trying to locate cicadas to sting and paralyze.
When each cicada killer catches and paralyzes a cicada, she flies the victim to a tunnel, takes it down to a cell, still alive, and lays an egg on it. The resulting wasp larva feeds on the paralyzed cicada, pupates through winter in its cell and emerges the next summer when the cicadas are active.
Those five kinds of insects on our lawn, the bumble bees, June beetles, digger wasps, annual cicadas and cicada killers, are fairly obvious during their time each summer, and quite intriguing to experience. They are all part of food chains of who is eating what.
We have a large vine of deadly nightshade on a planted viburnum bush. Right now that vine has several purple-petaled flowers with yellow stamens protruding beyond the petals, and green, yellow, orange and red berries. The different colored berries indicate they don't all ripen at once. And part of the attraction of this nightshade vine are the many furry, black and yellow bumble bees that visit the blooms to sip nectar and collect pollen. These are sterile, female, worker bees that take nectar and pollen from the blossoms to feed their younger, larval sisters in their nests in clumps of grass in the ground, while the mother of them all, the queen, continues to lay eggs in that grassy home in the soil.
Meanwhile that day, I saw several digger wasps feeding on nectar in clumps of tiny, pale lavender spearmint flowers. Digger wasps are three-quarters of an inch long with a one inch wing span. They are black with deep-orange abdomens.
Adult digger wasps visit flowers to sip sugary nectar and females dig in the soil to find the larvae of green June beetles, which live under ground in our yard. Female digger wasps sting each larva they find to paralyze it and lay an egg on top of it. The resulting wasp larva eats the June beetle larva, pupates in the ground through winter and emerges the next summer, ready to feed on flower nectar and reproduce themselves.
But the most intriguing of these interesting insects in our yard are the cicada killers that are in our neighborhood in abundance. There is a colony of female cicada killers that worked together in a patch of clay soil with sparse vegetation to dig out several branching burrows in the soil, each one with a few cells at the end. Each female digs with her front legs and kicks out the soil with her rear ones.
Meanwhile, we have annual cicadas all over our lawn. They had been brown grubs sucking sap from tree roots for at least one year. Then they dug out of the ground during some nights in August, leaving quarter-inch holes in the soil, and climbed trees, shrubs and other objects. After a while, the back of the exoskeleton, or shell, splits open on each grub and the adult cicada, complete with wings and horny plates under their abdomens on the males, emerged. After several days, many empty shells still cling to the objects the grubs climbed up.
The next day, and for several days after, the cicadas fly about in the trees looking for mates. Males vibrate the flaps on their abdomens to make the buzzing, whirring sounds we hear during the day and early evening to attract females to them for breeding.
I see both the chunky, dark cicadas and large, yellowish-orange cicada killers zip about among the trees and bushes. The cicadas are finding mates, but the female cicada killers are trying to locate cicadas to sting and paralyze.
When each cicada killer catches and paralyzes a cicada, she flies the victim to a tunnel, takes it down to a cell, still alive, and lays an egg on it. The resulting wasp larva feeds on the paralyzed cicada, pupates through winter in its cell and emerges the next summer when the cicadas are active.
Those five kinds of insects on our lawn, the bumble bees, June beetles, digger wasps, annual cicadas and cicada killers, are fairly obvious during their time each summer, and quite intriguing to experience. They are all part of food chains of who is eating what.
Sunday, August 23, 2015
Farmland Swallows and Sparrows in August
This morning, August 23, 2015, as I took a half hour drive through Lancaster County farmland from New Holland to Ephrata, I saw several flocks of post-breeding barn swallows, tree swallows and house sparrows along the rural roads I was on. The mixed groupings of swallows by the scores and hundreds were lined up on roadside wires, perched on corn tassels, bare-ground fields and some of the roadways, or zipping through the air in pursuit of flying insects to eat. Presumably, when the swallows' stomachs were full, the birds would perch to rest, digest and preen their feathers until hungry again. The house sparrows were on the country roads to ingest undigested grain in horse manure, or weeds and fox-tail grass to eat the seeds of those plants. When a vehicle approached, the swallows took to the air and the sparrows flew into the fields of tall corn and perched there until the vehicle passed by. But soon all the birds returned to their original positions to rest or feed again. Those swallows and sparrows made the trip to Ephrata more interesting.
These three species of small birds have adapted well to human-made cropland to their own advantage; hence their abundance everywhere in this county during summer of every year. Milk is big business in this agricultural county and with that livelihood are thousands of cows, and horses, which are the power on the farms of plain people. With those large animals comes manure, and millions of flies that were larvae in the manure. And there are lots of flies on those large farm animals themselves. Many of those flies are food for the swallows.
By mid-August, flies and other kinds of insects, including mosquitoes, had all summer to build up their numbers. Those multitudes of flying insects are abundant enough to feed the hordes of swallows that had also increased their numbers during the same summer and are now gathering in the hundreds and thousands per flock in preparation to migrate south to find flying insects still in abundance beyond the reach of the insect-numbing cold of the northern winter.
Another reason for the abundance of barn swallows and tree swallows in Lancaster County is that both species nest in human-made constructions. Barn swallows hatch young in barns and under bridges while tree swallows raise offspring in bird boxes erected for them and bluebirds. And, of course, in farmland, there is abundant flying insects all summer that feed those swallows.
Though plain in appearance for camouflage, house sparrows in their gatherings on the roads, roadsides and corn fields were interesting to experience, too. They were on the roads and shoulders to eat seeds.
House sparrows, too, rear youngsters in barns, and in crevices of any other human-made structure they can stuff grass into for a nursery. This species adapted to farmland in Europe, long before they were introduced to North America. And because they are seed-eaters and have adapted to sheltering in buildings and planted shrubbery at night, house sparrows are permanent residents wherever they may be. They do not migrate.
Obviously, swallows and house sparrows are not competing for food. Both groups of birds are pre-adapted for what they eat. The swallows have thin beaks, but wide mouths, not for cracking seeds, but for netting insects on the wing. The sparrows have thicker, stronger bills for cracking seeds, but the sparrows are not agile enough to snare a lot of insects in mid-air.
Swallows and house sparrows are small, but big in numbers and impacts on farmland in much of North America every year. People unknowingly have done well by them, by providing them with food and cover. And these little birds add beauty and intrigue to farmland, particularly in summer.
These three species of small birds have adapted well to human-made cropland to their own advantage; hence their abundance everywhere in this county during summer of every year. Milk is big business in this agricultural county and with that livelihood are thousands of cows, and horses, which are the power on the farms of plain people. With those large animals comes manure, and millions of flies that were larvae in the manure. And there are lots of flies on those large farm animals themselves. Many of those flies are food for the swallows.
By mid-August, flies and other kinds of insects, including mosquitoes, had all summer to build up their numbers. Those multitudes of flying insects are abundant enough to feed the hordes of swallows that had also increased their numbers during the same summer and are now gathering in the hundreds and thousands per flock in preparation to migrate south to find flying insects still in abundance beyond the reach of the insect-numbing cold of the northern winter.
Another reason for the abundance of barn swallows and tree swallows in Lancaster County is that both species nest in human-made constructions. Barn swallows hatch young in barns and under bridges while tree swallows raise offspring in bird boxes erected for them and bluebirds. And, of course, in farmland, there is abundant flying insects all summer that feed those swallows.
Though plain in appearance for camouflage, house sparrows in their gatherings on the roads, roadsides and corn fields were interesting to experience, too. They were on the roads and shoulders to eat seeds.
House sparrows, too, rear youngsters in barns, and in crevices of any other human-made structure they can stuff grass into for a nursery. This species adapted to farmland in Europe, long before they were introduced to North America. And because they are seed-eaters and have adapted to sheltering in buildings and planted shrubbery at night, house sparrows are permanent residents wherever they may be. They do not migrate.
Obviously, swallows and house sparrows are not competing for food. Both groups of birds are pre-adapted for what they eat. The swallows have thin beaks, but wide mouths, not for cracking seeds, but for netting insects on the wing. The sparrows have thicker, stronger bills for cracking seeds, but the sparrows are not agile enough to snare a lot of insects in mid-air.
Swallows and house sparrows are small, but big in numbers and impacts on farmland in much of North America every year. People unknowingly have done well by them, by providing them with food and cover. And these little birds add beauty and intrigue to farmland, particularly in summer.
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