Disturbance within an environment can have a substantial impact on the abundance of species present. Areas with high disturbance tend to foster low species diversity, while areas with low disturbance that tend to promote higher species diversity. In this study, the bird species diversity in natural settings was compared to that of a habitat with man-made characteristics. It was hypothesized that there would be less species diversity amongst birds found outside of a natural habitat. Four groups were tasked with observing the number of different bird species present within a specified location. In total, there were ten species of bird found in the natural habitats, while there were only eight species of bird found in the man-made habitats. Still, because the value of our statistical analysis was so low, we could not conclude that there was a significant difference in species diversity between the two locations. The results did not support the hypothesis, but this could have been due to the collection of data in one day and the overall adaptation of birds to their environment.

Introduction

Species diversity is exceptionally important in determining the overall health of a community and/or ecosystem. Habitats that contain high species diversity are more likely to withstand disturbances, as opposed to habitats with low species diversity. In a report written by WA Ntongani and SM Andrew, it is cited that researchers Hill et al. , along with DM Green and MG Baker, found habitats that have experienced some type of disruption tend to offer less species diversity in contrast to more resourceful natural habitats (2013). Another study conducted by Reijen et al. , found a lower abundance of bird species to be present in areas that produced significant interference and impeded their ability to communicate (Phipps 2000). The objective of this study was to determine if, within the Winthrop Recreational and Research Complex, bird species diversity in an area that fostered a natural habitat differed from that of a habitat that featured more man-made characteristics. We sought to observe whether or not there was truly any disparity between the two, or whether habitual conditions had little influence on species diversity in our areas of observation. Given the information above, I hypothesized that if a community of birds were located outside of their natural habitat, then there would be less species diversity present amongst the group.

Materials and Methods

Observation Areas

Experimental observations were recorded on the afternoon of September 12, 2018 at the Winthrop Recreational and Research Complex, located near the campus of Winthrop University in Rock Hill, SC. The 325-acre outdoor site consisted of a lake and wetland habitat, a wooded area with three succession plots (known as Winthrop Woods), soccer fields, softball fields, a golf course, a track and a nearby coliseum. The main areas of focus were centered around natural habitats and man-made habitats. We decided to narrow our scope, more specifically, to the lake and wetland habitat, the succession plots of Winthrop Woods, the softball fields and the parking lot of the coliseum. Winthrop Woods was created to serve as an area for students to survey and conduct research studies. In 1989, 50×50 meter succession plots were set aside to be intentionally undisturbed, allowing for future observations of the area (Winthrop Biology). This action was followed by the creation of two more succession plots in the years 1994 and 1999, respectively, to serve the same purpose (Winthrop Biology). The collective area has currently been in succession for about 30 years, to this point, and consists of a climax community of deciduous trees.

Observation Methods

The process began by dividing the class into four separate groups, each responsible for one of the areas shown in Figure 1. Each group contained about five students and was responsible for collecting data in their own respective fields. Groups were properly equipped with two to three sets of binoculars, a smart device consisting of the Merlin Bird ID application (to aid in the identification of birds), and pen and paper. Areas boxed in with different colors indicate the four different locations where observations were made. The parking lot and softball fields are outlined in red and yellow, respectively, while the wetlands and succession plots are outlined in orange and white. Data was only collected for one day, a Wednesday afternoon, for approximately one hour between the time of 3:45 PM and 4:45 PM. The weather was generally clear, with a slight overcast, and it should be noted that a significant storm was due to make landfall over the next couple of days. Over the course of the hour, each group surveyed their respective areas in search of different bird species, using natural eyesight, binoculars and their sense of sound. Individuals walked around the entire vicinity of their section scanning multiple sectors, including the skyline, areas of low ground, tree limbs, marshy wetlands, etc. , and made note of any bird they found. In an effort to make the process more efficient, each group designated two to three individuals to carry the binoculars and serve as observers, while the remaining individuals shared the responsibilities of using the Merlin Bird ID application (to aid in the identification of bird species) and being general note takers.

At the conclusion of an hour, all groups congregated back into the lab and consolidated all of their recorded data. My research group was tasked with surveying the parking lot of the Winthrop Coliseum. Two individuals, as stated above, were primary observers and used binoculars to scour the sky and tree lines that were within close proximity. Once a bird was spotted, general descriptions (color, size, bird calls, etc. ) were given to the note taker and to the individuals with the Merlin Bird ID application to determine the actual species. We began in the northwest corner of the parking lot, and traveled generally southeast throughout the duration.

Results

After combining all of the data from each research group, a total of ten different bird species in the natural habitats, and eight different bird species in the man-made habitats were found. There were three common birds observed in both areas: The Eastern Bluebird (Sialia sialis), the Northern Cardinal (Cardinalis cardinalis), and the Northern Mockingbird (Mimus polyglottos).

To determine if there was any significant species diversity amongst the birds present in the complex, we used the chi squared formula, where = chi squared value, = sum of all values, O = the number of observed bird species and E = the number of expected bird species (Equation 1). With our data, O = 10 for the natural habitat and O = 8 for the man-made habitat, while E = 9 for both. Given that our degree of freedom for this experiment was df=1, we needed to have a chi squared value greater than 3. 84 in order to support the proposition that there would be a difference in bird species diversity between the two areas (Figure 3). This value would correspond to the idea that our observations were not due to a matter of chance, but instead were a result of significant disparity between the two areas of concern. We, however, determined our chi squared value to only be 0. 22, indicating that our findings were not of any significance.

Equation 1. Formula for the calculation of chi squared value. In any given scenario, if you have a chi squared value that falls within the significant range, depending on your degrees of freedom, then you can be confident that your results were not due to chance. In calculating our degrees of freedom (number of groups – 1), we find that we only have 1 degree of freedom. Since our chi squared value falls below 3. 84, we cannot say with certainty that our results are significant.

Discussion

This study revealed that there was actually no significant difference in bird species diversity within the Winthrop Recreational and Research Complex, at the time. Although the natural habitats appeared to have an abundance of species slightly greater than that of man-made habitats, statistical analysis showed that the results were most likely due to chance. Originally, I inferred that there would be more diversity in the natural habitats since they were less disturbed and away from areas of high traffic. However, after only finding minimal difference between the two, and given such a low chi squared value, I do not have enough evidence to support my hypothesis, nor can I reject the null hypothesis.

There are several reasons that could have contributed to the results given above. Bird species within the complex may have adapted to their environment, as disturbed urban dwellings have exhibited the ability to offer a variety of resources, and to be hospitable for multiple species (Melles et al. 2003). Moreover, non-natural disturbance has been found to have a low correlation between the bird species diversity of two given areas (Ntongani and Andrew 2013). One must also consider that our survey was conducted for a single day and over the course of just one hour. This was only a one-time observation; no subsequent observations took place. There was also the impeding noise of individuals conducting the study, as well as no distinct method to survey any of the respective areas. In future studies, I would suggest multiple observations be made over the course of several days, each at different time intervals. I also suggest that each group examines more than one territory, as this would allow for better visualization of each area.

Furthermore, the addition of one standard method for every group to follow would aid in getting accurate results. In doing so, I would still expect to see results similar to the outcome of our study. I believe that bird species at Winthrop’s Recreational and Research Complex are suited to survive in this locale, and are thriving off of the resources that are provided to them.