Introduction
There is a global decline in amphibian population that is affecting many species of amphibians. The causes of this decline are habitat destruction, introduced species, over exploitation, climate change, UV-B radiation, chemical contaminants, disease, deformities, and synergisms. Habitat destruction is limiting the number of amphibians that can live of that land because of lack of natural resources. Introduced species are nonnative species that have been brought to an area of land and invade it. Over exploitation is when people come in and extract the animals and sell them as pets or for products of medicine. Climate change these small changes in weather effect the extremely sensitive amphibians and change breeding behavior. UV-B radiation the increase in this radiation can directly lead to the death on amphibians. Chemical containments are thing like pesticides, corroded metal, and acidification these can harm the habitat and kill amphibians. Disease is a very common reason for this which there are many of these diseases that can lead to sub lethal or even lethal results. Deformities have had a recent wide spread increase in amphibians and are now considered a major environmental problem. Synergisms which is multiple of these factors at a non-lethal level can cause damage at a lethal level. Amphibian decline is a serious problem and we are going to find a way to help.
National Statistics have shown amphibians decline in the past years thirty two percent of the amphibians in the world are threatened with extinction in the near future. And forty three percent of amphibian’s population are declining. South America has the most amphibian species in the world with 2231 which doubles the second most in a region. These statistics seem to be continually increasing which suggest that the rates will continue to rise. These rates are especially high in salamanders. These declines were also shown at high elevation in mountainous areas among 274 wetlands.
This research is important because we will be able to track how the egg mases increase and decrease amongst these upcoming years. And with the variety of project topics we will hopefully be able to find the ideal breeding conditions for these amphibians. This is important info because then we will be able to raise the number of embryos that the amphibians make. While rising the rate of the embryos that survive. If we are able to identify and act upon these slight preferences then we may be able to stop the decline in amphibian population. This will greatly impact the conservation of amphibians while helping the local community and parks like gulf branch.
Site Description
Gulf Branch Nature Center (GBNC) is located in Arlington, VA the vernal pool is located approximately one kilometer away from the Potomac River and is managed by Arlington, VA Parks and Recreation management. The GBNC vernal pool is .0231 hectares large while the whole nature center is 120 hectares. The vernal pool studied is located at 38” 55′ 09.5′ N in latitude and 77” 07′ 07.1′ W longitude, and is off of Military Road in Arlington, VA. The vernal pool at its deepest point is 48 cm deep. The forest cover of the Nature center is primarily Red Maple (Acer Rubrum), American Beech (Fagus Grandifolia), Red Oak (Quercus Borealis), Lizard Tail (Houttuynia Cordata), and Jewelweed (Impatiens Capensis). The forest is very densely canopied and the park has many hills. The vernal pool is relatively small and also located approximately one hundred meters away from Military Road in Arlington VA. Gulf Branch Nature Center was first established in 1966 the parks history has gone from living lands of Native Americans to a woodland retreat to now a public nature center. It was a woodland retreat after it was Native American land up until 1920 when it was sold, then forty years later was turned into a public nature reserve which it still is today.
Procedures
We arrived at gulf branch on March 23 of 2018, put on our hip waders, and got in the water. We went through a gridded vernal pool section by section. We counted the number of egg masses in each section. Then we took nine samples at different spots in the vernal pool and at different depths. We took two samples at the near end of the vernal pool, one at 5 cm deep and one at the bottom of the vernal pool. We took two samples on the right side; one 5 cm in depth and one at the bottom of the vernal pool. Then we took two samples on the left side; one at 5 cm in depth and one at the bottom of the vernal pool. Two samples were also taken at the far end of the vernal pool 5 cm deep and one at the bottom of the vernal pool. The other sample we took was a collective sample taken from a plankton tow that was pulled throughout the vernal pool to get a universal sample of the pond. We brought the samples back to school and tested each of the samples four times for their ph. Then we entered the data into a table that we used to compare the pH to the number of egg masses in the respective area on the vernal pool.
Primary Articles
According to Sherman and Van Munster, 2012, during their study of Acid Tolerance, and Water Preference in Newts of Vermont, they said that the different types of newts had different pH preferences and that some did not have a preference. The Taconic mountain newts choose the higher pH water 72% of the time and did show a preference of a high ph. But the Green mountain newts showed no preference to a high or low pH but ended up in the high pH water 70% of the time. This was interesting and could affect the two species living conditions because of density dependent factors. This research project used six different ponds in different ponds in Vermont testing pH of different areas and they were constantly monitoring pH levels and where the newts were. They collected pond water for the newts and put the newts they collected in tanks with pound water no older than 3 days prior.
According to Benjamin A. Pierce, John B. Hoskins, And Elizabeth Epstein, 1984 in an article about Acid Tolerance in Connecticut Wood Frogs. Less than 1% of wood frogs survived in solutions with a pH of 3.5 or below and that at a pH of 4.0 and below the surviving embryos commonly developed abnormalities. This study used a single breeding pond that was 110 meters in length and 27 meters in width and maximum water depth is 1 meter. The results showed that the most Lithobates sylvatica eggs were found in a pH of 7.2 to 7.6 but closely followed by the ones found in a water with a pH of 4.0. But the eggs had the highest hatching percent in waters with a slightly acidic pH between 6.0 and 5.0 with hatching rates between 82.6% and 72.3%. This data showed that the majority of the embryos were found in a slightly basic pH although the best hatching percentage was in a slightly acidic to neutral ph. The experiment was conducted at Bolles Road Pond which is ‘110 m in length and about 27 m in width’.