Saturday, March 23, 2019
The unprecedented rate of decline for frog populations worldwide is one of the most significant environmental problems of the 21st century. Reasons include the individual or synergistic effects of key drivers such as habitat destruction/modification, infectious disease, pollution, over exploitation for food and trade (pet, lab use), invasive species and climate change. Frogs are one of the oldest vertebrates to abandon water habitation and settle on land nearly 300 million years ago. Regarding their ecological role, frogs hold a very special position on the food web as they are an important diet of many animals. They check unwanted population of ticks, flies, mosquitoes and disease-borne vectors. Frogs are very critical to pollution in aquatic communities as their moist skin easily absorbs anything within the contact of water. Thus, scientists regard them as bio-indicators of the environment. It’s a matter of shame for the entire human race how such historically tough and resilient species are disappearing rapidly due to our irresponsible actions and currently, one-third of the global amphibian species (7,899) are threatened with serious risks of extinction.
Starting in 1995, cases of malformed frogs and missing limbs caught scientists’ attention in Minnesota and on the shores of Vermont’s Lake Champlain. Following that, mass abnormalities came into the lime light in the United States and Canada. Scientists’ noted that pollutants had lethal to sub lethal impacts on frogs leading to suppressed growth and development, while making vulnerable to the emerging diseases. The impacts were noticeable when mostly frog habitats exposed to waste water pollutants, especially nitrogenous chemicals from farmlands.
An infectious disease called Chytridiomycosis, caused by the chytrid fungus (Batrachochytrium dendrobatidis), is wiping out frog populations from the global map with the incidence reported in all six continents and over 40 countries. Chytridiomycosis has been detected as far north as Alaska and as far south as Tasmania, as high as 5348 meters and as low as nearly sea level. The disease has already put 200 species of frog to extinction until now, in less than 30 years of its discovery. Scientists trace back the emergence of chytrid fungus in late 1930s, when African clawed frogs were shipped globally for research and used in pregnancy testing. While there is lack of evidence on how chytrid fungus propagate naturally across geographies, huge portion of the infected frogs are reported from the frog trade industry. Frogs are exported heavily from China, Indonesia and other Asian nations to meet the global demand of frog leg’s consumption, for educational and scientific purposes.
It is now abundantly clear that the Earth’s climate is changing in response to anthropogenic greenhouse-gas emissions. Average annual global temperature has risen by 1°C since the last century and expected to grow 1.5°C by 2040 (IPCC report). The rate of increase has been greatest in the latter part of the century. The effects of escalated temperature can alter oxygen uptake, mating cycle, inhibit development and metamorphosis, induce tadpole mortality and sex reversal in frogs. Temperature increase will also affect distributions of species seeking higher elevations. Alterations in precipitation pattern have obvious negative consequences seen in shrinking breeding habitats and delay in reproductive behaviors. Even excess rainfall is detrimental to frogs that are dependent over aquatic habitats with lesser flow. The large scale impact of these changes will have implications on the food web structure and even interactions between species in the community. Species like American Bullfrog and Cane Toad are a serious threat to all native amphibians around the globe because of their easy dispersal capability anywhere in the world. These exotic species compete with the native populations for common resources and wipe out them so quickly off its natural habitat.
While frogs are being pushed to the brink of extinction, we can still help them out and reverse the decline that requires trade-off between environmental, economic and social pillars of growth. Infrastructural development like roads in the vicinity of frog habitat could fragment populations and even facilitate the spread of invasive species by disrupting native communities and changing physical habitats. Hence, environmental consideration should be taken while planning for road development. Level of pollution and pesticides should be controlled in farmlands and runoff in pools/streams/creeks as we can see exceeding level could have dire consequences in frogs. The disease management programs should be regularly monitored and significant learnings to be incorporated ultimately. A well-defined Frog Conservation Action Plan has to be a part of a broader national conservation effort and integration of outreach programs among the general public.
Tuesday, August 14, 2018
Wednesday, August 8, 2018
Wednesday, May 9, 2018
Rapporteur: Ms Bandana Adhikari, EGH Coordinator
Amphibians are ectothermic animals providing the evolutionary link between fish and reptile. They are divided into three orders: Gymnophiona, Caudata and Anura. All frogs and toads fall under Anura. The total number of recognized species has increased by over 60% since 1985. In Nepal, there are 53 species of amphibians (1 newt, 4 toads, 47 frogs and 1 caecilian). Over 2,000 amphibian species are threatened with extinction i.e. one-third population and about 200 species have already been extinct since 1979. Amphibians play a significant role in the functioning of ecosystem. Amphibian populations have suffered widespread declines and extinctions in recent decades. The amphibians of Nepal have been facing severe threats of extinction mainly due to rapid deforestation, soil and water pollution, land use changes, habitat loss, unplanned resource extraction and exploitation in the academic sector. The major cause of the decline in the population of amphibians is due to the ignorance of people and lack of awareness about the importance of amphibians. So, every year on the last Saturday of April since 2008, the amphibians admirers celebrate “Save The Frogs Day” in different parts of the world with the main aim to protect amphibians and encourage the public to conserve amphibians and respect nature and wildlife.
This year the 10th Annual Save The Frogs Day was marked in Nepal on 28th April at Indreni Food Land, New Baneshwor, Kathmandu, with the financial help from SAVE THE FROGS! USA and support from Resources Himalaya Foundation and Environmental Graduates in Himalaya (EGH). The main motive of the program was to discourage frog dissection practice in biology labs. The event had a wider participation of college and university students, zoology teachers, conservationist, academicians and media person. Mr Biraj Shrestha, Research Officer at Resources Himalaya Foundation (RHF) and SAVE THE FROGS! volunteer was the event coordinator and supported by volunteers from EGH.
The program started with a welcome note by Ms Binita Pandey, Research Assistant at RHF, and presentation of short video clip about the decline in the number of frog’s species. After that, there was the keynote presentation of Mr Biraj Shrestha, Research Officer at RHF on the topic entitled “The Downside of Frogs Dissection” where he highlighted the importance of frogs and their role in the ecosystem and the decline of frogs due to several threats. He further disseminated the role of dissection in the decline of the number of frogs and said that dissection is one of the major threats to some frog’s species in Nepal. He concluded that alternatives can be brought in practice to solve the problem of dissection.
The program was then followed by discussion among the participants. Mr Khubi Ram Adhikari, Deputy Director of Curriculum Development Centre, assured that it’s high time to revamp the curriculum and apply the substitutes if possible. Mr Rishi Shah, Academician of NAST, expressed his view about the frog’s day and its importance. He highlighted the need of cooperation among all to further work together in the field of conservation. Ms Shristi Singh Shrestha, Project Manager of The Jane Goodall Institute, expressed her sincerest support in ending cruelty to frogs in the name of dissection and Mr Shailendra Pokharel, Executive Chief of CODEFUND, shared his idea about the conservation of amphibians.
The discussion round was followed by poster release from Ms Shristi Singh Shrestha that contained the message of frogs decline due to dissection and the alternatives to dissection.
Dr Dinesh Raj Bhuju, General Secretary of RHF, had his concluding remarks about the evolution of frogs and their role in the ecosystem. He highlighted the shortcomings of dissections and said that the modern education has been misled and urged everyone to understand the importance of frogs and start loving them.
We are very much thankful to SAVE THE FROGS, USA for providing financial support to execute the event and also thanks to our volunteers of EGH and Ms Bandana Adhikari, EGH Coordinator for their dedication. We wholeheartedly are grateful to all the people who participated in the event and helped us to spread the message of amphibian conservation.
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