Field Observations:
July 21, 2013
It was a cool morning as I rode my bike out to the prairie to make my weekly observations. With a temperature of 73 degrees Fahrenheit and the wispy clouds keeping the sun at bay, I managed to make it there without breaking out in a sweat. Dressed in jeans, ready to tromp through the tangle of plants, I was thankful for the reprieve from the hot temperatures that the previous week had provided. Riding my bike past the length of prairie on S 650 W I observed the flutter of life that was occurring within this small patch of land. Small Cabbage Whites danced between the flowers never stopping for more than a second on a single bloom. I had planned to turn left onto W 100 S and travel to the opposite corner of the prairie. I figured I would make my way in amongst the flowers to see if I uncovered any major differences in the species found on that side.
Although this had been a great plan, my short attention span meant a change in action. As I parked my bike in the ditch amongst the grasshoppers that had made their home in this frequently mowed long grasses I soon became distracted. Perhaps it was a new awareness gained from our class experiences helping to bird band this week, or it could have just been the birds were as grateful for the cool air as I was, but I could not help notice their very active behavior. I made my way in a little ways and found a nice place to sit amongst the flowers. There, I sat so I could watch and listen.
The first thing that drew my attention was a little critter flitting around in the tree on the edge of the prairie. I couldn't help but think he was boisterously expressing his lack of approval with me being in his territory. He kept chirping at me, for lack of a better word. Short little bursts of sound, always taking care to stay hidden within the tree. After several minutes I was able to catch sight of him as he flew to a new branch, flashing his bright red patch on his wing to let me know he was not happy. Having figured out this mystery bird was none other than a Red-Winged Black Bird I turned my attention to the other choir of birds that were singing away. Amongst the many calls I could tell there were several birds I did not know. I did however recognize the distinct ping-pong ball dropping sound of the Field Sparrow.
After several minutes I noticed that not only were the birds calling much more this morning, but they were also showing off their wonderful aerial acrobatic skills. Two Goldfinches danced together near the telephone wires, their distinct yellow flashing against the black of their wings. They dive-bombed at each other, taking each others place on the wires, seeming to enjoy a playful banter between each other. There was also a small flock of what appeared to be a species of swallows. They had a distinct forked tail, but without a bird guide along to help me identify them further I was at a loss. At least next week I will know how to prepare before heading out to visit my new friends amongst the prairie. This week will be spent studying up on the bird calls commonly found in a prairie, and a field guide for birds will be tucked into my backpack. Although there is much more to discover in the future I rode away having uncovered several more secrets of the prairie.
Species Identification:
Pasture Thistle (Cirsium pumilum)
This biennial plant begins its first year by creating a rosette of prickly leaves. The next year the stem that shoots up will reach heights of 1-3 feet. This plant is fairly recognizable because of its irregular purple shaped flower head. The flower head is approximately 2'' in diameter and is made up of numerous disk florets.
Aside from the recognizable flower the deeply lobed leaves that are quite spiky would let any curious person know what family this plant belongs in. The leaves are alternating along the stem measuring up to 9'' long and 3'' across. One distinguishing feature of this plant is that the top of the leaf is green, whereas the bottom appears to be a powdery white due to the minute hairs there. Also, as can be seen in the picture, the stem of this species does not have spikes.
This hardy plant is able to survive in more disturbed habitats, but can also be found in many prairies. Its preference is full sun with mesic moisture levels in the soil. During times of drought the bottom leaves will turn yellow and fall off to help the plant conserve its energy. Tufts of white hair develop on the achenes which helps this flower spread its seeds through wind dispersal.
"Pasture Thistle (Cirsium discolor)."Illinois Wildflowers. N.p., n.d. Web. 22 July 2013. <http://www.illinoiswildflowers.info/prairie/
Common Eastern Bumble Bee (Bombus impatiens)
There is some suggestions that this bee is named for the flower that he frequently visits, the Impatiens, but after my observations of this little species I'd agree more with the assumption that he is the "impatient" bumblebee. A male bee of this species measures at 12-17 mm. It is recognizable by its pale T1 and all black T2. It is also known for its medium tongue length.
Being the most often encountered bee across most of Eastern NorthAmerica this species has several adaptations that have given it a competitive edge. These include its large colony size and long flight season. This species is particularly important to the prairie ecosystem since it acts as one of the key pollinators amongst the flowering plants.
"Species Bombus Impatiens - Common Eastern Bumble Bee." Welcome to BugGuide.Net! - BugGuide.Net. N.p., n.d. Web.
21 July 2013.
Cabbage White ( Pieres rapae)
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| Photo Source: Unknown |
With a smaller wingspan of only 4.5-5.8 cm this butterfly is a mere flash of white as it flutters from bloom to bloom. If it were not for the immense number of them present they may have been more difficult to spot. This species ability to survive in a variety of habitats including weedy areas, garden areas, roadsides, and even cities make them quite prolific. This probably is influenced by the fact that they will nectar from a wide array of plants including dandelion, mustards, asters, and mints. The host plant, where they lay their eggs, is species in the mustard family.
The white wings of this species make it easy to recognize along with the black tip. This sex of this species of butterfly can be determined by examining the number of submarginal black dots. A female will have two whereas the male will only have one.
"Attributes of Pieres rapae." Butterflies and Moths of North America. N.p., n.d. Web. 21 July 2013. <www.butterfliesandmoths.org/species/Pieris-rapae>
American Goldfinch (Dominiquito viajero)
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| Photo Courtesy of: The Cornell Lab of Ornithology |
This bird is quite distinguishable due to his bright yellow color and black wings with white wing bars. The female is a duller version of the male, but both birds have a drab coloring for their winter foliage.
A small bird, its conical beak is a sign of its food source, which is why he was likely hanging out in the prairie. The plethora of flowers from sunflowers, thistles, grasses, and the splattering of trees around the edges of the prairie provide plenty of sources of seeds for the goldfinch to indulge on.
Being the only finch that molts twice in a year, its newly bright feathers in late winter is a welcome sign that spring is coming. Breeding later than most birds, they do not nest until July when their food source is more bountiful. Interestingly it has been found that their strictly vegetarian diet has proven to keep the Brown-headed Cowbird who lays their eggs in other birds nests from surviving in their brood and outcompeting their young.
" American Goldfinch, Life History, All About Birds - Cornell Lab of Ornithology ." Your online guide to birds and bird watching . N.p., n.d. Web. 22 July 2013. <http://www.allaboutbirds.org/guide/americ
A Second to Consider Succession:
This small piece of prairie is considered to be in its second stage of succession. Since it was once farmland, the use of the field for crops would be considered the initial disturbance. The plowing of the field and constant planting of different species for harvesting would have disrupted the natural fauna that would have been present. As the farmer may have noticed throughout his crops there is always a rich seed bank waiting for the opportune time to grow which is the first stage in succession. A farmer's annoyance with these species has coined them obnoxious weeds, but for a more positive connotation in terms of nature retaking what was once hers we will use the term pioneer species. As soon as a farmer quits working to eliminate these plants they will quickly take over. The many seeds created for wind-pollination means these plants are ever present and can quickly take root and sprout.
The second stage in succession comes with appearance of biennial plants. The first year these plants make their appearance they will only be present with their basal leaves. These plants have the unique adaptation of putting all their energy into a strong root system which will give them the upper-hand over the annuals the following year since they will already be established. The buzz of life we hear within the prairie could clue us into this stage without even glancing at the plant life there since we know these biennial plants depend on insect pollination.
If left to nature's course, eventually woody perennials and shrubs would take advantage of the higher moisture levels created from the plant life already growing there and would soon begin to grow. With conservations efforts to conserve prairies a burn regimen is usually put into place. Prairie burns take place in the early spring. The biennial plants with their established root system go unaffected by the burn and gain the upper hand over any plants that may be pushing towards further succession.
Jackson, Marion T. (Ed.). (1997). The natural heritage of Indiana. Bloomington, IN: Indiana University Press.
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