What Does it Mean to Have a World Without Frogs? — Global Change and the Living World

Author: Hien Thach, Edited By: Autumn Berlied

Frogs have a substantial role in the ecosystem; they control the insect population as well as serve as a source of food for mammals. Frogs also can benefit humans through the compounds secreted through their mucus-covered skin. Researchers have found that some secretions were used to produce new antibiotics and painkillers. Frogs are sensitive to water pollution and acidic rain. These issues are anthropogenic changes, meaning we as humans caused them. While they are good study organisms for determining how climate change impacts them as a single species, it also goes to show how crucial they are to their ecosystems. If frogs are affected by either water pollution or acid rain, it can cause anything from deformed limbs to feminized male sexual organs in frogs (1). Of course, the biggest long-term threat to frogs is climate change...not predators. All frogs are ectothermic, which means that all frogs rely on the external environment to control their body temperature. Chytrid fungus is a major threat to frogs, especially Rabbs’ fringe limbed tree frogs (1).

Rabbs’ Fringe Limbed Tree Frogs

Now, you are probably wondering what are Rabbs’ fringe limbed tree frogs? Rabbs’ fringe limbed tree frogs are considered “critically endangered” by the IUCN Red List and possibly extinct. Rabbs’ fringe limbed tree frogs, also known as Ecnomiohyla rabborum, are large, nocturnal frogs that feed on insects and can use their webbed hands and feet to glide in the forest canopies of central Panama when they feel threatened. The chytrid fungus (Batrachochytrium dendrobatidis) causes an emerging infectious disease called chytridiomycosis (2). The fungus colonizes to form vegetative masses on the skin of amphibians, such as frogs. The fungus then collects energy from the keratin in the skin of the amphibian. We are not sure exactly why or how the fungus kills the frogs, but there are two prevailing theories that exist: the fungus produces lethal toxins or due to the presence of the fungus, exchange of oxygen and carbon dioxide through the skin is interfered. The decline in the population of frogs is a huge issue. To help out with this situation, you must know that frogs love (1) water - frogs have spent their early life cycle in water and (2) shelter - the skin is not waterproof, so the passage of gases may be affected. The rise in climate changes fuels the chytrid fungus potentially by the control of water loss in frogs (4). This explains that the fungus has a strong, indirect role with frogs.

Figure 1. This is an Ecnomiohyla rabborum in the forest canopy of central Panama (3). https://en.wikipedia.org/wiki/Ecnomiohyla_rabborum — Figure 1. This is an *Ecnomiohyla rabborum* in the forest canopy of central Panama (3). https://en.wikipedia.org/wiki/Ecnomiohyla_rabborum

What does it mean to have a world without frogs? It means that the food chain would crumble, less scientific research and testing, an increase in insect populations, an overall increase of greenhouse gas emissions, and even potential disease outbreaks. Frogs are a species in our ecosystem that function as a natural population control (5). We are all living in an amphibian crisis! Increasing our efforts in factors that we are able to control such as reducing carbon emissions and extending our research and knowledge on infectious diseases is a great start.

Citations:

(1) Wilson, T. V. (2008, February 5). How Frogs Work. Retrieved from https://animals.howstuffworks.com/amphibians/frog5.htm.

(2) IUCN SSC Amphibian Specialist Group 2019. Ecnomiohyla rabborum . The IUCN Red List of Threatened Species 2019: e.T85341796A54357363. https://dx.doi.org/10.2305/IUCN.UK.2019-1.RLTS.T85341796A54357363.en. Downloaded on 13 February 2020.

(3) Ecnomiohyla Rabborum. Wikipedia, Wikimedia Foundation, 8 Nov. 2019, en.wikipedia.org/wiki/Ecnomiohyla_rabborum.

(4) Wilson, Tracy V. “How Frogs Work.” HowStuffWorks, HowStuffWorks, 5 Feb. 2008, animals.howstuffworks.com/amphibians/frog6.htm.

(5) Mendelson III, J. R. (2011). Lessons of the lost. American Scientist, 99(6), 438-442.

(6) Mendelson, J. R. (2011). Shifted baselines, forensic taxonomy, and Rabbs’ fringe-limbed treefrog: the changing role of biologists in an era of amphibian declines and extinctions. Herpetological Review, 42(1), 21-25.