July 6, 2009
In the morning mists, a new world is revealed.
Posted by Danelle Haake at 8:08 AM
March 25, 2008
The weather may still be chilly, but the birds are telling us that spring is here. The Cardinals are belting out their "chew chew chew" calls, the chickadees are singing and the woodpeckers are busy drumming their territory on tree trunks.
Spring also means the commencement of the nest box season. Carolina Chickadees, Eastern Bluebirds and Eurasian Tree Sparrows may begin nesting as early as mid-March (though April is usually the month the eggs begin appearing) and the boxes were already showing signs of activity the first week in March. After checking boxes yesterday it is safe to say that the nest building portion of the breeding season is underway. More than half the boxes contained material and several times I witnessed birds leaving the boxes. I was lucky to capture this photo of a Eurasian Tree Sparrow entering a box with some nesting material.
Many have asked me if any of the nest boxes contained evidence of Eastern Bluebird activity and sadly the answer is no. Though the Bluebirds are not true migrants and stay in the same spot year round, I think they only pass through our prairies for food before flying to a nearby area to breed. There are at least 2 golf courses near LREC and it has been my experience that Bluebirds find this type of habitat favorable for raising their young. Late last summer Malinda Slagle and I discussed possible ways to encourage Bluebirds to use the nestboxes and this past winter she and the Friday volunteers moved the boxes located on the woodland edge into the prairie. Time will tell if this entices the Bluebirds into our nestboxes. I do plan to continue research additional ways to encourage the Bluebirds to nest in our prairie.
However, Litzsinger Road Ecology Center is one of the few places in the United States that have a breeding colony of Eurasian Tree Sparrows. Back in 1870, German Immigrants homesick for the birds from their homeland released 20 Eurasian Tree Sparrows in Lafayette Park. Since then these birds have spread through St. Louis and St. Charles Counties and Madison and Calhoun Counties in Illinois. These sparrows are found nowhere else in the United States and birdwatchers from all over will make a special trip to St. Louis just to see them. Being an avid birdwatcher myself, I feel truly fortunate to have been able to check the boxes and handle these unique birds over the last 2 years.
The Eurasian Tree Sparrows were not the only birds active at LREC. One of our resident Red-shouldered hawks was seen flying around between the barn and the classroom.
A pair of Canada Geese were grazing on the pasture prairie.
And there were dozens of Robins foraging on and near the burned prairies.
Spring is a busy time of the year and there will be a great deal of growth and activity in the next few months. Be sure to stay tuned for further updates on the nest boxes and other spring sightings!
Posted by Colleen Crank at 11:41 AM
December 4, 2007
This recent cold snap got me thinking about our feathered friends. Winter is a difficult time of the year for the birds. Not only do they have to deal with cold temperatures, but limited food and water supplies. Many fruits and berries are gone and bugs and insects are hard to find. A lack of rainfall has diminished water resources and cold temperatures have frozen most existing water supplies.
Most bird species will switch from a diet of insects and fruits to a diet of seeds and grains during the cold winter months. Chickadees, Titmice, Downy and Red-bellied Woodpeckers and White-breasted Nuthatches will store insects and nuts for winter consumption and join flocks that contain several bird species to forage for food.
You can help those seed-eating birds by putting birdfeeders up in your yard and there are some seed that are better than others to feed during the winter. Oil sunflower seed has high fat and protein content and most birds can eat this seed due to its thin outer shell. Cardinals, Blue Jays, chickadees and woodpeckers are especially fond of Black oil sunflower seed.
Of course variety is the spice of life and you can include a good seed mix to attract other birds. Many seed mixes include Black Oil Sunflower Seed, Striped Sunflower Seed, Safflower Seed and Millet. It will not be unusual to find Mourning Doves, Carolina Wrens, Chickadees, Cardinals, Blue Jays and Sparrows dining on a good seed mix. Just be sure that any seed mix you purchase does not contain milo, as this is a filler and the birds will simply toss it to the ground. Goldfinches and House Finches enjoy Thistle. Thistle is a tiny seed that needs a special feeder but can easily be found in grocery, feed, department and bird feeding specialty stores.
And don’t forget those ground-feeding birds! White-throated Sparrows, House Sparrows, Mourning Doves, Dark-eyed Juncos (and Cardinals too!) usually forage for seed on the ground beneath the feeders. I usually place a healthy amount of millet under my feeders for these birds, but you can avoid the mess and purchase a ground feeder that has been made for this purpose.
Suet is also an excellent source of fat for our feathered friends, especially since the birds need a high number of calories to keep their bodies warm. Suet is rendered beef fat that is prepackaged and sold in grocery, feed, department and bird feeding specialty stores. Sometimes the suet will contain other ingredients, such as peanuts, peanut butter, seed, insects and fruit. You can also make your own suet and recipes are easily found on the Internet. The base ingredient for most homemade suet is peanut butter, but Crisco or lard is a great substitute for those with peanut allergies.
Woodpeckers are especially fond of suet, but you may also find Carolina Wrens, Chickadees, Titmice and Blue Jays flocking to your suet feeder.
Whole Peanuts are another source of high fat and protein. You can either buy a peanut feeder or string them with yarn on your feeder or in the trees. And the same birds that enjoy suet will snatch those peanuts up to eat.
Water is just as important to these birds as food. Obviously water is prone to freezing this time of year, but hardware stores and bird feeding specialty stores sell immersion heaters and there are birdbaths that have built-in heating units.
Not only do the birds benefit from the seed and water, but you do as well! It’s fun to watch our feathered friends hop and flit about the feeders. You can keep a tally of the different bird species you see at the feeders, watch their eating behavior or see how often the birds go the water for a bath or a drink. You can also participate in Cornell Lab of Ornithology’s Project Feeder Watch or Great Backyard Bird Count as a citizen scientist.
Whether you decide to keep it simple or get involved with observations, make sure you feed the birds this winter!
Posted by Colleen Crank at 2:13 PM
September 3, 2007
What bees live at LREC? That's exactly what Malinda wants to find out. Malinda has been capturing pollinators by netting them, but this summer she tried something new. She drew on the help of our summer program students to collect bees using a fun, new protocol that was developed by Sam Droege of the USGS Native Bee Inventory and Monitoring Lab.
In the a.m. of the day of the research project, Malinda set up two transectsone in the prairie and one in the woods. (A transect is a straight line used for sampling, such as to count the occurrence of a species in order to estimate its population size.) Along each transect she placed a plastic cup, or "bee bowl," every 5 meters. The cups alternated in color (white, blue, yellow) and were filled with soapy water. The idea is that the bees are attracted to the color and can't help themselves from flying into the soapy water.
The captured bugs were placed in specimen bags that were carefully labeled with the transect name (PRAIRIE or WOODS). A piece of paper inside the bag recorded other information, such as the date and the color of the cup.
The next step was to dry the bees. The students did so by spinning the bees in salad spinners. Why? To give lift to the bees' hairs. If the hairs are matted, the bees are even more difficult to identify.
Posted by Heather Wells-Sweeney at 12:17 PM
April 22, 2007
Spring has sprung at Litzsinger Road Ecology Center. Several woodland flowers are in bloom, the trees and bushes have leafed out and a chorus of birdsong fills the air. Out in the prairie the Eurasian Tree Sparrows are busy at work in the nestboxes. Our feathered friends have been building nests, laying and incubating eggs and now raising chicks! There are chicks in 7 of the 12 boxes scattered across the Litzsinger property. By March 1st there was already nesting material in the boxes and the chicks have hatched at least one week earlier than last year. Because this is only our second year monitoring the boxes in earnest, (I posted an entry last year. See it here) we do not know whether or not the birds’ early activity is due to the unseasonably warm weather we had back in February and March. It will be interesting to watch the trends in nesting and chick activity in the years to come.
This is the youngest clutch and they are no more than a day old. These tiny birds will grow quickly and leave the nest in another 2 weeks.
Photo by Lyndell Badewall
In this photo you can see what a different a few days can make. These little birds are probably about 5 days old.
Photo by Lyndell Badewall
This chick is probably about a week old.
Lyndell Badewall, a fellow LREC volunteer and undergraduate UMSL student has been assisting me in my monitoring endeavor and through Lyndell we are going to be able to band these birds. Each bird receives 3 color-coded bands. The site’s designated color (orange for LREC) goes on the left leg and 2 different colored bands go on the right leg. Each color combination is unique and makes it easy for us to track the bird’s movement habits, nesting activity and even its age through observation of the colored bands.
Last week we banded 4 chicks and this week we plan to band 6 more clutches worth of chicks. It will be interesting to keep up with our feathered friends and their day-to-day habits. If you happen to see a Eurasian Tree Sparrow in the upcoming weeks and months, look for the colored bands and report your sightings. We’ll be happy to share your enthusiasm for our special friends.
This looks to be a promising season so I will post notes on the blog this spring and summer on continued activity in the nest boxes.
Posted by Colleen Crank at 4:12 PM
April 13, 2006
As you may have noticed, there are several bluebird nestboxes scattered across the LREC property. The horticulture staff and volunteers worked hard earlier this spring in building and placing these boxes around the prairie and forest edge and for the last month, I have been checking these boxes.
I have checked nestboxes in other areas in St. Louis in the past and based on my previous experience, I was eager to check these nestboxes because I had several questions in mind. Who would use these boxes and if there were competing bird species, which would be the dominant species? How sensitive to human disturbance would these birds be? What would happen if I opened the box and caught the adult sitting on the nest? Would that bird decide to abandon its nest? How suseptible to predation are these nestboxes and do the ventilation holes in some of the boxes make a difference in nest mortality rates?
Some these questions will not be answered immediately, but what I can tell you is that 10 out of the 12 boxes are occupied by Eurasian Tree Sparrows. As of today, the remaining 2 boxes have some nesting material at the bottom of the box but it is too soon yet to determine the species that is making the nest.
I am rather excited that the Eurasian Tree Sparrows are occupying the boxes. St. Louis is only one of a few places in the United States that supports a population of these birds. While the Eurasian Tree Sparrow is a non-native species, they do not appear to be aggressive like their cousin the House Sparrow. In fact, Eurasian Tree Sparrows will move out of areas where there are House Sparrows. House Sparrows and European Starlings vigorously compete with other birds for nesting sites and it is not uncommon for these 2 non-native species to kill native birds or boot them out of a prime nesting location. As I have stated earlier, Eurasian Tree Sparrows will simply move to another location to find good nesting spots.
I've developed a process to checking the boxes. I usually check the area immediately around the nestbox. I know there's a good chance a nestbox is occupied if I see a bird leave the box prior to my arrival or I see or hear a pair of birds fussing at me from a nearby tree.
Then I open the box and peer inside. At times, opening the lid to these boxes is similiar to opening a Christmas present because you never know what you are going to get. I've learned the hard way to NEVER open a box and blindly stick a hand inside. The first and only time I stuck my hand into a box without looking, my hand came back covered in ants. NOT a pleasant experience. In the past I have found frogs, mice and even a snake sitting in nestboxes and have had to back off from hornet's nests.
The next step in checking a box is determining who is occupying the box based on the nest that is inside. Most of the time the bird will be long gone by the time I arrive but identifying the nest is relatively simple process. Bluebirds have tidy nests composed of twigs, plant stems and some feather down. Chickadees also create a nice neat nest, but theirs is composed mostly of moss. Eurasian Tree Sparrows however, create an orb-shaped nest and cram the box full of dry grass, sticks and feathers with the inner portion lined with down. As you can see here, it can be difficult to stick a hand inside.
This is the point where I will blindly feel around for eggs or birds. (It is usually safe at this point to poke around blindly, since I have determined there will be no unpleasant surprises) The birds create a narrow tunnel from the entrance of the box down to their eggs while the remainder of the box is filled to the gills with plant stems and such. It is amazing how crammed full these boxes can get.
Eurasian Tree Sparrows have oval, creme-colored eggs that have varying degrees of brown spots and speckles.
Eurasian Tree Sparrows will usually begin nesting in April and can have up to 3 clutches of eggs during the breeding season, which lasts into August. These birds will lay 4-6 eggs that will hatch after 11-14 days of incubation. The young birds will leave the nest 12-14 days later.
After a month of checking the boxes, I have come up with more questions. Why are the Eastern Bluebirds not using the nestboxes? Both the Bluebirds and Tree Sparrows begin nesting around the same time. Are the Eurasian Tree Sparrows reaching the boxes first, before the Bluebirds? Or are there enough natural cavities for the Eastern Bluebirds to use for nesting sites so they are simply not interested in the boxes? Have the Bluebirds used the boxes in the past, or has it always been the Eurasian Tree Sparrows? Or, is it possible that the LREC property just isn't quite a prime location for Bluebirds to raise young? These questions will require a few years of nestbox observation and birdwatching before they can be answered.
In the meantime, keep your eyes peeled for young Eurasian Tree Sparrows. They will be coming!
Baicich, Paul J, 1997, A Guide to the Nests, Eggs and Nestlings of North American Birds. San Diego: Natural World Academic Press.
Sibley, David Allen, 2001, The Sibley Guide to Bird Life and Behavior. New York: Alfred A. Knopf Publishing.
Posted by Colleen Crank at 4:27 PM
March 13, 2006
Bird life is abundant at LREC. You can hear the busy chatter of the Eurasian Tree Sparrows around the parking lot or sit on the deck and watch the steady stream of Cardinals, Blue Jays and Woodpeckers that frequent the feeders. A visit to the prairie will reward you with the sight of brightly colored Goldfinches hopping from flower to flower and you may hear the cry of a Red-Shouldered Hawk as he soars overhead in the sky.
This activity falls with the setting sun but in the hush of twilight a different set of birds emerge from the shadows. The Owls. Owls are remarkable creatures that have many impressive adaptations that help them live and hunt under the pale light of night. We are fortunate to have Great Horned Owls, Barred Owls and Eastern Screech Owls living on or around the LREC property. Here we will shed some light on the mysterious world of our owl friends.
ADAPTATIONS FOR HUNTING
As you may have noticed, owls have large eyes and if our eyes were to be just as big, they would be the size of softballs!
These huge eyes gather in a great deal of light, allowing the birds to see 10–100 times greater than humans do in poor light. Like humans, owls have forward-facing eyes that give them an increased depth perception when hunting and looking for places to perch. But unlike humans, owl's eyes are fixed in their sockets and they must move their heads to focus on different objects. To compensate for this limitation, owls have an extra bone in their neck that allows them to rotate their heads 270 degrees in either direction. So that means, if an owl were to turn his head to the right, he could continue to turn his head until it rested on his left shoulder!
An owl's sense of hearing is just as important as his sight and is so keen that it is possible for this bird to hunt by sound alone. The disc of feathers around an owl's face gathers in and funnels sound into the ear canals, which are located just behind the eyes.
The ear openings are asymmetrically placed on the owl's head, giving the bird a sense of three-dimensional hearing. When a potential prey item is spotted, the owl will bob his head up and down and from side to side, taking in sound from all directions as he triangulates the precise location of his next meal.
Once the owl has sized up his prey item, he will swoop down in silence on that unsuspecting rabbit or mouse. You may be wondering how that creature did not hear the owl's approach and the answer lies in the feathers. Each feather on the owl's wings have softened serrated edges and a fuzzy upper surface, muffling sound as these feathers move through the air.
An owl's talons are also adapted for successful hunting. These birds have zygodactyl feet which means that the outer toe on each foot can swivel back and forth, giving the owl the option to have 2 toes in the front and 2 toes in the back, providing a strong, even grip on its squirming prey. When the owl has captured his prey, he will either tear it apart with his powerful beak or swallow it whole, gulping down the prey headfirst. The owl's digestive system will take the bones and fur of its prey and compact it into a pellet, which the owl will regurgitate at a later time.
Owls, particularly the Great Horned Owls, are probably the earliest nesting birds in the St. Louis area. Great Horned Owls begin courtship as early as November and begin nesting in January and February.
Adult Great Horned Owl
Young Great Horned Owl
The Barred Owls begin breeding in February and March.
Adult Barred Owl
Young Barred Owl
Screech Owls nest later in the spring, starting in March and continuing through the month of May.
Adult Eastern Screech Owl (Red Phase)
Young Eastern Screech Owl
The owls do not build their own nests; rather they will reuse a nest, such as an abandoned hawk or squirrel's nest. Great Horned Owls prefer a platform-type nest over a cavity nest but Barred and Screech Owls will use tree cavities and nestboxes to raise their young. Owls lay their eggs every 1–2 days but will not begin incubation until after the second egg is laid. The male primarily delivers food to the nest but the female will assist her mate once the owlets grow older. There is some variation in the length of time the different owlet species remain in the nest, but most of these young birds begin fledging about a month after they have hatched. The owlets will rely on their parents for food for several weeks after they have left the nest.
CHALLENGES TO SURVIVAL
There are several obstacles the owl must overcome in order to survive and a big challenge they face today are pesticides. An owl may not be directly affected by the consistent consumption of a poisoned mouse or insect, but the indirect effects of pesticides can be costly. Abnormal eggs, small clutches and owlets with birth defects are some of the secondary effects of pesticide use. The widespread use of pesticides also diminishes the owl's constant food source. Habitat loss, automobile traffic and outdoor cats are other factors that affect owl mortality. Loss of habitat affects the availability of nesting sites for the owls and it is not uncommon for owls to collide with cars while hunting at night. Cats are problematic because they kill owlets and the smaller owl species.
There are many ways people can help the owls survive. Retaining large trees and even old buildings is helpful because owls often use these structures as nesting sites. You can also build or purchase nest boxes for Eastern Screech Owls and Barred Owls. Limiting the use of pesticides and other poisoned baits, keeping cats indoors and reporting people who shoot or steal owls to Operation Game Thief are ways you can make life easier for these birds.
This entry has only scratched the surface on the mysterious world of the owls. Be sure to check out the books, nestcams and websites listed below to learn more about these fascinating birds!
Eastern Screech Owl Nest cam
Great Horned Owl Nest Cam
MO Department of Conservation
Building Nest Boxes
Baicich, Paul J, 1997, A Guide to the Nests, Eggs and Nestlings of North American Birds. New York: Academic Press.
Sutton, Patricia and Clay, 1994, How to Spot an Owl. Vermont: Chapters Publishing Ltd.
Sibley, David Allen, 2001, The Sibley Guide to Bird Life and Behavior. New York: Alfred A. Knopf Publishing.
Posted by Colleen Crank at 6:16 PM
November 9, 2005
A few weeks ago when I parked my car on the LREC parking lot, I noticed a bustle of activity in the bush directly in front of me and found a half dozen Eurasian Tree Sparrows. I smiled and continued to watch the birds hop around in the bush, foraging for seeds and chipping to their neighbors. Before my time with the LREC, I had checked songbird nestboxes for two summers and there were two locations where Eurasian Tree Sparrows used these boxes. I fell in love with these birds and watching them develop from naked tiny baby birds into fully feathered functioning birds of an avian community made the days of walking in the hot sun, trudging through stinging nettle and poison ivy and dodging wasps that inhabited the nestboxes worthwhile.
During that first year of checking the boxes, I learned that the Eurasian Tree Sparrows were found only in the St. Louis area (though now I have since learned that there are small populations as far north as Iowa) and serious birders from all over the country came to our city to get a glimpse of these birds. You can only imagine my excitement when I learned there was a small population of Eurasian Tree Sparrows on the LREC property.
The Eurasian Tree Sparrows can be easily distinguished from their House Sparrow cousins by the presence of a black dot on their white cheek patch. They also have a rusty brown cap and lack the black bib commonly found on the House Sparrow.
Eurasian Tree Sparrows are native to Europe, Asia, China, Japan, Siberia, northern India, Taiwan and southeast Asia. These little birds do not belong to the sparrow family but rather the weaver family and there are at least 33 subspecies of Eurasian Tree Sparrows found within its wide range.
In April 1870, 20 Eurasian Tree Sparrows were released in Lafayette Park. During this time, it was common for immigrant residents to release European birds to control insect populations and fulfill their desire to see the birds from their homeland. The House Sparrow, another European bird released in the eastern portion of the United States, began its encroachment into the St. Louis area around 1878, forcing the Eurasian Tree Sparrows out of their established territories. While the House Sparrow populations exploded over the United States, the Eurasian Tree Sparrow numbers remained small but steady in the St. Louis area and surrounding counties.
Today the Eurasian Tree Sparrow is commonly found in St. Louis County and City, the floodplains of eastern St. Charles County and in Calhoun and Madison counties of Illinois. These sparrows prefer to live on farmland and other open, cultivated areas but will move into parks and suburbs to avoid living in close proximity of their aggressive House Sparrow cousins.
Eurasian Tree Sparrows are primarily seedeaters, eating weed, corn, millet, wheat, and sunflower seeds, grass and seed shoots though the adult sparrows will feed their young offspring a diet of insects and spiders. Eurasian Tree Sparrows mate for life and will nest in colonies during the breeding season, raising their young from nestboxes, tree cavities and even the crooks and eaves of houses and buildings.
The Eurasian Tree Sparrow creates an orb-shaped nest with the outer layer composed of coarse grass material while the inner portion of the nest is lined with down and finer vegetative matter. The eggs hatch after about 2 weeks of incubation and the young birds fledge at 15-20 days of age.
Why is it that the Eurasian Tree Sparrows have remained in a limited area, while other introduced European birds such as the Rock Pigeon, European Starling and House Sparrow have flourished all over the United States? There is no definite answer, though there are several possibilites. It is common knowledge that House Sparrows are much more aggressive than Eurasian Tree Sparrows and dominate food and nesting sources where the territories of the two species overlap. Studies have also shown that Eurasian Tree Sparrows do not migrate and the newly fledged offspring do not wander far from the nest to establish their territories.
There are several places to find these St. Louis specialty birds. Keep in mind these birds like open land, will perch in shrubby areas and nest in big thick tree cavities. Be forewarned that finding these birds may be no easy task. Birding is like fishing. Both require a great deal of preparation, patience, tenacity and the ability to deal with disappointment if the day doesn't go as planned. Eurasian Tree Sparrows are easier to find during the fall and winter months, where they flock in fairly large numbers to feed and forage on the ground. Spring and summer are a hit-and-miss time of the year as the birds are busy breeding and raising their young.
There have been consistent sightings of the birds on the floodplains found on Aubuchon and Missouri Bottom Roads. Marais Temp Clair Conservation Area in St. Charles, the Riverlands Environmental Demonstration Area and the gravel road leading into the Edward "Ted" and Pat Jones - Confluence Point State Park, both in West Alton, are sure places to find the sparrows during the winter. You can also find Eurasian Tree Sparrows in Sioux Passage Park and St. Stanislaus Park in North County, Grafton Ferry Road and North River Front Park in north St. Louis. In Illinois, Eurasian Tree Sparrows have been spotted at Horseshoe Lake and the Brussels Ferry in Calhoun County.
The Webster Groves Nature Study Society leads weekly bird walks and have created a website that is rich with information on St. Louis wildlife. They have also published an excellent book, Birds of the St. Louis Area: Where and When to Find Them that include information on the Eurasian Tree Sparrow. You may also want to call their birding hotline to find out the latest bird sightings (314) 935-8432
For those of you who visit the LREC site with your students, look for the Eurasian Tree Sparrows in the shrubs next to the parking lot, at the feeders on the deck and along the south prairie. You may even want to try your luck and put up a bird feeder or a nestbox at your school. Good luck and I hope you get a glimpse of the bird found only in the St. Louis area.
Sibley, David Allen. 2001. The Sibley Guide to Bird Life and Behavior. New York: Alfred A. Knopf, Inc.
Webster Groves Nature Study Society. 1998. Birds of the St. Louis Area: Where and When To Find Them. Missouri: Murray Print Shop, Inc.
Posted by Colleen Crank at 6:44 PM
October 29, 2005
There's no question that fall has arrived at the LREC. The morning air carries a crisp chill, the last of the prairie flowers have died and the trees have begun to change colors.
Have you ever wondered what causes the leaves to turn those brilliant shades of red, orange and yellow, and why it seems that the autumn foliage is more colorful some years than others?
Let's begin with the leaf.
The carotenoids, the pigment responsible for the fall colors, is already present with in the leaf but is concealed by the green color of chlorophyll, the component essential for photosynthesis. The base of each leaf contains a special layer of cells, known as the separation layer, where the exchange of water and food between the leaf and tree takes place.
The leaves are responsible for providing food for the tree and it performs this duty through photosynthesis. In photosynthesis, the leaves use water and carbon dioxide to produce carbohydrates for the tree and oxygen is the by-product of this process. On any given day, the average tree will take in 1-1/2 pounds of carbon dioxide and release about a pound of oxygen into the atmosphere. The leaves also produce more food than is needed and the tree will convert the excess sugar into starch to consume during the winter months.
The shorter hours of daylight and cooler temperatures trigger a reaction that allows the leaves to reveal their autumn colors. During this time, the cells within the separation layer form a cork-like material that cuts the exchange of water and glucose from the leaf. The chlorophyll within the leaf disappears when the water supply is cut off, revealing the hidden oranges, reds or yellows.
The orange leaves are produced from carotene pigments,
yellow leaves are a result of xanthophyll pigments
and anthocyanin create the red and purple leaves.
Interestingly enough, not all trees produce anthocyanin and this pigment is only made during the fall months.
Contrary to popular belief, rainfall is not the only factor responsible for the colors of autumn. Sunlight, cloud cover, temperature and soil acidity also determine the intensity and duration of fall's colorful show. For example, bright light produces anthocyanin. The brighter the sunlight, the more vivid the red and purple leaves. A warm wet spring followed by a summer that is neither too hot nor too dry that leads into a fall with warm sunny days and cool nights will produce a dazzling leaf display.
Now that you know the work the leaves put into their visual displays, I hope you get a chance to go outside and enjoy the last days of Autumn's splendor.
Jonas, Gerald. 1993. The Living Earth Book of North American Trees. New York: The Reader's Digest Association, Inc.
King, John. 1997. Reaching For the Sun: How Plants Work. New York: Cambridge University Press.
Stern, Kingsley. 2000. 8th Edition. Introductory Plant Biology. Boston: McGrawHill.
Posted by Colleen Crank at 7:28 PM
October 15, 2005
The woods and the prairie at the LREC are teeming with life. On any given walk you may see a squirrel scamper across your path or hear the chatter of a Belted Kingfisher as he hunts for food on the creek. On the prairie you can admire the vibrant Purple Coneflower and watch the bees walk across the goldenrod in search of pollen and nectar.
We tend to focus on the flora and fauna that is immediately and easily visible to our senses. But have you thought about the life that is hidden within a rotting tree, under the leaves or in the ground? There's a whole other world down there, where the decomposers, also known as the detritivores abound. What may seem like a dead tree at first glance is actually a tree teeming with life.
There are decomposers hidden within the crevices of the bark, working hard to break the wood down into material small enough for microscopic bacteria to break that matter further down into good, fertile soil material.
And who are these decomposers? Let's take a look under a tree stump and find out.
The sowbugs are usually the first decomposers you will notice under a rotting tree stump.
These bugs are also known as pill bugs and roley poleys. They enjoy hiding in dark, moist places such as our tree stump. They mostly eat dead plant material and have a sturdy exoskeleton that protects them from harm.
The slug is another decomposer you may find under the rotted tree log. The slugs are members of the gastropod class and they eat leaves, dead plant matter and fungus. The slug moves via its muscular foot and produces two different types of mucus to aid in its movement. The mucus also helps the slug retain much-needed moisture and protects it against potential predators.
There are several critters that enjoy the taste of a slug and these include Beetles, Centipedes,Lizards, Mice, Shrews, Moles, Frogs, Toads, Birds and Fox.
The snails, also in the gastropod class, share several characteristics with the slugs. They move by the same muscular foot, depend on moisture for survival, produce mucus for locomotion and protection and live in the same habitat.
There are a few differences between snails and slugs. Snails have shells that provide protection and a place to retreat during a dry spell. During those times when no water is available, the snail will retreat into its shell and go into a state of estivation, which is similar to hibernation. When rain moistens its immediate environment, the snails come out of their shells and resume their task of eating dead plant material, bark and young plant shoots.
I wanted to include this picture to show you just how tiny these snails were. There is a snail on either side of my finger. Can you find both of them?
These beautiful mahogany-colored wood roaches are quite different from the roaches you may find in your home. These roaches feed exclusively on wood and they contain tiny microorganisms within their digestive tracts that help them break down the wood material they eat. The adult wood roaches feed their offspring, as their young initially lack the beneficial bacteria to help break down their food.
If you find these roaches in your house, it is because they have stumbled in purely by accident. They will do no harm to your house as they much prefer their damp homes within the woods.
Isn't this a shiny, beautiful beetle? These Patent Leather Beetles live within old logs and eat the decaying wood. Their trees of choice are the black and white oaks, American Elm, Yellow Poplar, American Beech and Sweet gum. These beetles live in colonies and within their wood homes they dig tunnels, creating "galleries" where they lay eggs and rear their young. The young beetles stay in the larval stage for about a year and their parents feed them fecal material mixed with wood chips.
There are a lot of other animals in the forest that dine of these beetles. Wood Frogs, Toads, Mice, Snakes, 5-lined Skinks, Moles, Opposums, Wild Turkeys and Woodpeckers.
The centipedes are one of the prime predators of the decomposers. These fast-moving venomous insects eat cockroaches, spiders, termites and a variety of other insects. They have one pair of legs per segement and have claws that aid them in catching their prey.
I found this gem under a rotted tree stump in the woods of LREC. Isn't it beautiful?
Well, that concludes our brief exploration of the hidden life of decomposers. I've only touched on the surface of these fascinating creatures. I didn't even talk about the millipedes, spiders, termites and other recyclers of the environment. Explore them for yourself and have fun learning!
Pechenik, Jan A., 2000. Biology of the Invertebrates. 4th ed. New York: McGraw Hill
Posted by Colleen Crank at 10:17 PM
October 10, 2005
On September 27, I made a special trip out to the Ecology center with my camera. I wanted to capture the last colors of fall before winter's cold set in. Here are my thoughts and pictures from that day.
Before the Europeans set foot in North America, over half of the state of Missouri was covered in Prairie grasses. The soil was loamy, silty and fertile for the taking. Over time, Missouri's native habitat was transformed into farmland and urban development. Today less than 2% of natural prairie remains but there is a new movement within the Natural Sciences community to rebuild prairie habitat. The Missouri Botanical Garden here in St. Louis is doing a fantastic job of recreating prairie habitat. The MO Botanical Shaw Nature Reserve out in Gray Summit MO has some impressive prairie habitat and the Litszinger Road Ecology Center has a wonderful small piece of prairie land as well.
There is so much life out in the prairie of the Litszinger Road Ecology Center. (LREC) Right now most of the flowers are past their prime and beginning to die off, but some colorful blossoms remain.
Right now the Goldenrod is abundant and a flurry of life surrounds these beautiful prairie flowers.
The prairie is a harsh place and the grasses, flowers and animals that inhabit the land must adapt to a dry, hot climate. Prairie plants have roots that grow deep in the earth, deeper than other plants to be able to reach water. American Goldfinches nest later in the summer, past the time when all the other birds have raised their young. These birds time their nesting activity around the blooming of thistle and coneflowers so that they have a good food source for themselves and their young.
Goldfinches also lose their bright yellow feathers and take on a more drab appearance once Autumn sets in. Here are a few pictures of a female American Goldfinch.
As of September 27 a few hummingbirds were still found lingering around the feeder set at the edge of the prairie. But most of our ruby-throated gems have migrated south now.
This is life on the prairie during Autumn. I look forward to watching the land and its inhabitants change with the seasons. Stay tuned!
Posted by Colleen Crank at 9:46 PM