It is well known by now that frogs
are great indicators of environmental changes because of their skin. Every element
of nature that they come into contact with, they are affected by. Atrazine
found in water can alter the internal reproductive organs in male frogs. There
are two other water pollutants that are a cause of concern for frogs: birth
control pill and parasites.
Every time someone takes birth
control or other forms of estrogen such as skin creams and prostate cancer
medication, they are excreting the chemicals through their urine and into waste
water or other ground water resources. For a long time it was thought that only
Atrazine, the herbicide used in farming, was the only culprit for finding male
frogs containing both testes and ovaries. This is not true. A study done in
various water resources around Connecticut are proving that birth control is another
contributing factor found in our water that is polluting our frogs’ fragile
bodies.
Ecologist and associate dean at Yale
University, David Skelly, is heading the research being done in Connecticut to
understand why birth control is getting into water resources. During Skelly’s
research he found that frogs living “in agricultural areas, only 7 percent of
the frogs show these deformities” and frogs in “urban and suburban areas, it’s
about 20 percent” (Burgeson, 2010). This is important because it means that
birth control and estrogen medication is a problem for frogs living in urban
and suburban areas.
When medications are being disposed
of either through the body or being flushed in whole down the toilet, they are
not always finding their way to sewer systems where they can be treated and
eliminated from drinking water. John Herlihy, director of water quality and
environmental management for Aquarion Water Co,. states that “it’s because
those water bodies are receiving wastewater discharge” (Burgeson, 2010). This
means that there are flaws in the water treatment that ends up in the
groundwater or drinking water. When we add medication to the mix, it is
extremely hard to eliminate every single chemical because it would be awfully
expensive for cities to do so. In addition, water treatment centers are not
aware of what people are flushing down the toilet and that is why they campaign
and stress to people to not do so.
One way the
EPA is trying to do their best by removing estrogen in drinking water is by adding
chlorine or powdered activated carbon (Burgeson, 2010). This is not the best
way to go about but so far it is one of the only few alternatives until either
other forms of birth control are used or other alternatives are found to do
away with estrogen in our water which harms our frogs. Skelly brings up a good
point when he mentions that “we could end up medicating the natural world, and
even re-medicating ourselves” (Burgeson, 2010).
Those humans who do not take estrogen medications should not be introduced
to it through their drinking water and nor should our frogs reproductive organs
be in jeopardy.
Another alarming introduction to our
water source is the introduction of harmful parasites that are deforming our
four legged amphibians. In various water sources in Minnesota and the
Midwest, there is an increase of a specific snail species that is a host to a
parasite called trematodes. The increase of snail population is due to nitrogen
and phosphorus used in farming sites. Trematodes are harmful to the frogs
because “larvae burrow into tadpole limb regions and form cysts that disrupt
normal frog and toad leg development, causing extra or missing limbs” (Johnson,
2012). Missing limbs, extra limbs or deformed limbs are hazardous to the frogs’
survival because if they cannot escape from their prey, they will decline at a
faster rate. Or vice versa, if they cannot hunt for food because they are not
fast enough they will starve to death.
The life cycle of the trematodes is
serious. An increase of snails means a decline in frog population. As the frogs
who are deformed fall victim to prey by birds, the birds then excrete the
parasite and then find their way to a host and the cycle starts all over again
(Johnson, 2012).
On a lighter note, there is some
good that frogs can do to help the environment without losing their life or
altering internal organs. In countries where there is very little financial
assistance to help protect, preserve or control water quality, frogs are now
seen as a safe alternative to test unsafe polluted drinking water.
Dr. Tyrone Hayes has discovered that
in Ethiopia and Uganda the reed frog in males’ skin changes when the water
quality is poor. The males are normally green but took the appearance of the
females. Thousands of experiments were
conducted on frogs to prove Dr. Hayes theory that “During the metamorphosis
from tadpole to adult, frogs are very sensitive to changes in their
environment, including chemicals in the water or their food supply. So the
changes in coloration indicated that the frogs’ extremely thin, sensitive skin
was reacting to the contaminants in the water” (National Geographic). Dr. Hayes
was correct and had an idea for developing countries to test their water.
The reed frogs could be a low-cost solution to countries where lack of government assistance or environmental organizations can test the quality of water. If the local people raise the frogs and observe color changes in male frogs, then they would know that the water has pollution, plastic by-products, pesticides or synthetic hormones (National Geographic). This could be a good solution provided the only adverse effect to the frogs is just color change and nothing else that would lead them to extinction.
Sources:
Burgeson, J. (2010, Feburary 28). For frogs, and perhaps humans, there’s something strange in the water. Retrieved from http://www.ctpost.com/news/article/For-frogs-and-perhaps-humans-there-s-384390.php
Johnson, P. (2012, May 22). Richer parasite diversity leads to healthier frogs, says new cu study. Retrieved from http://www.colorado.edu/news/features/richer-parasite-diversity-leads-healthier-frogs-says-new-cu-study
National Geographic. (n.d.). Explorers bios- tyrone hayes . Retrieved from http://www.nationalgeographic.com/explorers/bios/tyrone-hayes/