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For Ornithology class, we were divided into groups to study bird behavior. Our group became intrigued with the competition of feeding behavior among perching birds and ground foraging birds. The main question that continued to arise was whether there was a competitive relationship between these two groups, the first question being whether perching birds attracted foraging birds or not. As birds perch on a feeder and eat, seeds fall from the feeder to the ground. From this fact, our first goal was to examine if there was a correlation if perching birds being at a feeder leads to ground forager or other unrelated groups to come near the feeder and exhibit interspecie competition. Based on this data, our next question was whether there was a level of competition present among each group and between each group. The number of birds were counted in descrete values to observe how birds interacted with one another.

In the article, Potential winter niche partitioning between Tufted Titmice (Baeolophus bicolor) and Black-capped Chickadees (Poecile atricapillus) by Correia, black-capped Chickadee and the Tufted Titmouse competition was compared. Results show that Black-capped Chickadee tended to stay in the niche that was higher in ground than the Tufted Titmice that mostly done ground foraging. Since the Tufted Titmice is larger in size, it is hypothesized that Black-capped Chickadee avoided on purpose not to be on ground so that it would not have to compete. The data was collected by using a JC record to tape the behavior at the bird feeder. The location each bird stayed and forage was taken as data and the dot was used to tell how Black-capped Chickadee and Tufted Titmice interacted with each other.

Our method was to study two feeders; one feeder is in an area that experiences a moderate level of human traffic while the other is on a trail that experiences relatively low human traffic on a daily basis. We wanted to test out whether human traffic would affect the number of birds that were coming to each feeder; we tried to do our data collections around the same time in order to ensure that time would not be a determining factor; however, there was a margin of human error in the form that we all went when we were able to fit the visit into our schedule. Our experimental sites were at the Silvan parking lots forest bird feeder and the forest bird feeder at the path that leads to Orchard Hill. We chose those sites because they are within walking distance from where everyone lives. We plan on conducting our experiments at least four times a week until April 11,  a week before the project is due. We plan on observing bird competition on different days and different times in order to avoid pseudoreplication. We have two sites; they are not that far apart so we will most likely have to find another site because if we use our current two we run a high risk of pseudoreplication. We will also do a variety of individuals and pairs when it comes to data collection; during the pair collection ideally, you collect data individually just to ensure randomization of data.

We hypothesize that there is a strong correlation between the presence and number of perch-feeding birds and the number and presence of ground-foraging birds. We also hypothesize that within interspecific feeding competition between perch-feeding birds as well as the interspecific feeding competition between ground-feeding birds that size and innate behavior will determine dominance, and therefore access to the feeder. Our hypothesis is that size will be the biggest factor in terms of feeding success. It is expected that the species that have a larger body mass, girth, or height and exhibits more aggressive behaviors, such as displaying wings and bills, pecking, or mobbing will be capable of outcompeting smaller and more docile species between the two groups that we are studying.

As a group we became intrigued with the dynamics between perching birds that use feeders as their source of food and foraging birds that rely on food that they find on the ground. The main question that continued to arise was whether there was a competitive relationship between these two groups, the first question being whether perching birds attracted foraging birds. As birds perch on a feeder and eat, seed will be dropped from the feeder to the ground. Understanding that, our first goal was to examine if there was a correlation between a bird being at a feeder and the appearance of a ground forager or if they were unrelated and both groups operated individually from one another. Our next question was whether there was a level of competition present among each group and between each group.  As a result, our group decided to analyze the interspecific feeding competition between perch-feeding birds as well as the interspecific feeding competition between ground-feeding birds.

The essential element required for plant growth depends on which growing stage the plant is in at a certain a specific time. In agriculture, farmers analyse the nutrient concentration in the soil to make sure the plant is in its most desirable condition to maximize their growth. There are two types of analysis used to see both conditions of the plant and the soil. With modern understanding of pollution and climate change, people are favoring organic fertilizers over chemical ones. The organic fertilizer has less nitrogen so it reduces the amount of pollution. The mechanism of how plant take in the nutrients from the soil is by a process called mineralization. Roots will absorb the nutrients deep in ground. Most nutrients are taken in by the roots, however, leaves are capable to absorb some nutrients as well. This discovery gave advantage to the agriculture because the process of absorption is much rapid compared to the root absorption which the rate can change depending on that day’s soil’s condition.  

The element the plants want at a certain time depends on what growing stage the plant is in. In agriculture, farmers will analyse the nutrient concentration in the soil to make sure the plant is in its desirable condition to maximize its growth. There are two type of analysis used to see both conditions of plant and the soil. With modern understanding of pollution and climate change, people are favoring organic fertilizers over chemical ones. The mechanism of how plant take in the nutrients from the soil is by a process called mineralization. Roots usually will absorb the nutrients but leaves are capable to absorb some nutrients as well. This discovery gave advantage to the agriculture because the process of absorption is much rapid compared to the root absorption which the rate can change depending on that day’s soil’s condition.  

Soil is a complex thing after all. It is a heterogeneous mixture with inorganic particles that may have charges on them. Since soil is composed by so many different factors, the pH, temperature, ratio of each element can all be different from one day to another. For the plant to be able to obtain sufficient amount of nutrients without being affected by the soil condition, plants have developed a complex root system. Each plant specie may have a different shape and number of roots, but they all serve the same purpose to get nutrients from the ground. Researchers also claim two hypothesis about roots. One is that each part of the roots absorb different type of nutrient. In other words, the nutrient absorbed at the tip of the root and at the middle part of the root is not the same. The other one says that the entire root surface absorb the nutrient. The two hypothesis are true depending on which plant specie the researcher is talking about.

Biparental care can be easier than being a single parent. But the workload is still massive. In the bird groups that show delayed dispersal, there is a helper male that assists the actual breeding male to protect the territory. For the caring the young, the actual parents will take care of it. But to reduce the stress of protecting the territory while feeding the young, birds such as Siberian Jays learned to have a helper male that did not breed in that year to help them to watch the territory from being attacked. This is a method that did become advantageous allowing the population to survive better. The birds that follow this strategy also show replacement in partners too. If the breeding male dies during the breeding season, there are cases the helping male becomes the new father for the nestlings so they will continue to have biparental care.

About 90% of the birds are monogamous. In order to choose the best fit mate must be done carefully. The quality females look for depends on the species. For example, the red-winged blackbird females will bese their choice depending on how much resource the male has in his territory. The more territory and resources the male has, the more females are attracted. On the other hand, the long-tailed widowbirds females are attracted to males that have a longer tail. The preference of usually is besed on appearance or territory for most females but some species ask for both qualities to be sufficient. Most females will stay with one male and the male will do the same. However, if the female decides that the male is not good enough, she will reproduce with a different male to increase the success in reproducing.