1. Damselfly Biodiversity in the Peconic River
Briannan Green, Kylie Harrison, Maheen Safian, Andrew Serres
Mentor: Mr. Robert Bolen
Eastport South Manor Jr-Sr High School
Abstract
This project was based on the objective of attempting to find a change in biodiversity in our local Peconic River, and to detect any fluctuations in it from previous years. Our 17 out of 20 samples were processed and identified in the barcode system. We found a complete lack of diversity in the various damselfly species inhabiting the Peconic River. Additional studies will need to be completed to determine if there is an underlying environmental factor impacting damselflies. The effect of specific, multiple species being missing from the Peconic ecosystem has the potential to have a harmful effect on humans living in the community around it. For instance, damselflies eat “nuisance” insects that exist in the area. A decrease in the biodiversity of the species means that there is a high probability of disease transmission, unknown changes in the food chain, and a decrease in the quality of the river system.
Introduction
Biodiversity is the variety of life and organisms in a particular habitat or ecosystem. It is the foundation of an ecosystem that has been impacted by human life. The biodiversity of the Peconic River has been relentlessly tampered with by daily human activities. This, in turn, has caused significant consequences for the environment. Instances such as fluctuating nitrogen levels, harmful uncontrolled Algal blooms, and concentrated pollutants such as stormwater and cesspool remains leaking into major waterways have contributed to the loss of biodiversity in the Peconic River. Damselflies are predators throughout their whole life, and prey on particular insects like mosquitoes and macroinvertebrates, specifically, mosquito larvae. This largely contributes to the reason as of why they are so important and vital to our ecosystem. Without damselflies, there would be an increase in the mosquito population thus intensifying the transmission of diseases. Through DNA barcoding, we sought to achieve these goals:
Identify the species of damselflies we collected in the Peconic River.
Compare characteristics and genetics of different damselfly species.
Find similarities and differences between their similar parallel, the dragonfly.
Establish a baseline of the biodiversity in the Peconic River for future studies.
Materials & Methods
DNA samples were taken from the Peconic River and collected from algae, mud and other growth from the pilings to collect more specimen.
We cut and extracted the DNA from the abdomen, then applied primers that recognized the gene COI in order to isolate the COI (cytochrome oxidase 1) gene.
The primer and DNA solution had dideoxynucleotides added to the tube so that additional copies of the CO1 gene could be produced using Polymerase Chain Reaction (PCR) sequences were then compared to known DNA sequences using DNA Subway to compare our sequences to the Genbank database using the NCBI tool BLAST.
Discussion
Our question was, what is the extent of biodiversity of Damselflies in the Peconic River estuary? Our results from this research project were shocking and more than surprising. Alarmingly, there was little to no biodiversity in the samples we randomly collected from the Peconic river. Only three species were identifies out of the 17 samples. This indicates that a factor in the area may be eliminating specific strains of damselflies or that there may be intense competition. Damselflies serve as an important predator in the food chain, eating nuisance insects such as mosquitoes that aid in disease transmission, eventually harming humans. The decrease in these damselflies will hopefully remain on close watch after our research to make sure their decline does not continue at unnatural rates throughout the years. Low diverse numbers in damselfly species suggest that there may be a certain reason why some species do not survive. It is unknown why but it can be inferred that the surviving species of damselflies have adaptations that allow them to not be affected by what is killing off the others. Over the passage of the next three years, there is a chance the biodiversity might fluctuate and differ again, indicating the restored balance.
Results
The DNA subway alignment viewer shows the percentage of various samples in our project. Out of 20 sequenced samples, 17 samples produced sufficient DNA for sequencing using gel electrophoresis. Through BLAST on DNA subway, we were able to determine bit scores and the number of mismatches for each sample. Typically, a high bit score and a high number of mismatches showed a new species. Although these samples did not reveal a new species, three species were able to be identified. One sample (006) is potentially novel due to the high number of mismatches with a 91% sequence similarity. Additional sequencing will confirm the novelty of this sequence.
References:
"Biodiversity & Human Well-being." 1. Biodiversity: What Is It, Where Is It, and Why Is It Important? N.p., n.d. Web. 09 Dec. 2016
"DNA Learning Center Barcoding 101." DNA Learning Center Barcoding 101. N.p., n.d. Web. 13 Dec. 2016
@PondRiverStream. "Damselflies - Freshwater Habitats Trust." Freshwater Habitats Trust. 4- N.p., n.d. Web. 09 Dec
Damselflies. N.p., n.d. Web. 09 Dec Smoke, Chanelle. "How Humans Affect Our Ecosystem In Positive And Negative Way." 6 Prezi.com. N.p., 11 Nov Web. 09 Dec
"What Is DNA Barcoding?" What Is DNA Barcoding? – IBOL. N.p., n.d. Web. 09 Dec
"The Xerces Society » Ecology and Conservation of Dragonflies and Damselflies." The Xerces Society » Ecology and Conservation of Dragonflies and Damselflies. N.p., n.d. Web. 09 Dec
Acknowledgements
The Polaris team at ESM would like to thank our mentor Robert Bolen, in addition to Barcode LI staff for running additional PCR reactions for our group. Thank you to Sharon pepenella for delivering supplies and retrieving DNA samples for sequencing.
Figure 1: First run of samples revealing three definitive species of damselfly and a potentially novel sequence
Figure 2: Results of our second run of samples revealing only two species
Enallagma signatum (Orange Bluet):
samples 004, 009, 013, 014, 015,
016, 018, 019
Photo courtesy: dragonhunter.net
Enallagma divigans (Turquoise Bluet):
samples 010, 011, 012, 018, 020
POTENTIALLY NOVEL Sample 006 with BLAST hits below
Lestes rectangularis (Slender Spreadwing) or Lestes unguiculatus (Lyre-tipped Spreadwing)