San José, Costa Rica, since 1956

Global Warming Affects Frogs, Other Species

The effects of global warming mayseem distant – like biblical previews to anapocalypse not expected for many generationsto come. According to some scientists,however, rising temperatures havealready left irreparable marks on the world,and they are not far from home.A recent article in the U.S.-basedNational Wildlife magazine lists CostaRica’s golden toad, a native species thatdisappeared from its mountaintop habitatof Monteverde in 1989, as the “first speciesextinction attributed to global warming.”Biologist Allan Pounds, from theTropical Science Center of the privateMonteverde Cloud Forest Preserve, saidscientists believe the extinction of at leasttwo species of amphibians in Costa Ricacan be attributed to climate change.“We believe the golden toad (Bufoperiglenes) and the harlequin frog(Atelopus sp.), two species endemic toMonteverde, were wiped out by globalwarming in the late 1980s,” he told TheTico Times. Another 18 species of highlandfrogs have not been sighted for nearlytwo decades, though scientists have notlabeled them extinct yet, he said.Luis Diego Marín, the director of theprivate nonprofit Association for thePreservation of Wild Flora and Fauna(APREFLOFAS), said amphibians are themost susceptible species to global warming.“Amphibians are particularly affectedby climate changes because of their sensitiveskin and their incubation process,”Marín said.According to Pounds, amphibians area better indicator species of climate changethan other species, such as lizards, whoseprotective scales make them less sensitiveto climate changes.IN the past century, reported worldaverage temperatures have risen by 0.6degrees Celsius (1 degree Fahrenheit),according to Pounds.Scientists are predicting even warmertemperatures in the coming years.In Costa Rica, average temperaturesare expected to increase by 1.2 degreesCelsius (2 degrees Fahrenheit) by the year2030, and 3.4 degrees Celsius (6.1 degreesFahrenheit) by 2100, according to a studyby the San José-based Regional HydricResources Committee (CRRH).“This increase is based on an intermediatescenario, where measures to reduceconsumption of fossil fuels and alternativeenergy options are implemented but do notoperate at an optimal level,” said committeemeteorologist Patricia Ramírez.“IT is alarming – some natural systemsare not able to adapt to change thatexceeds 1 degree Celsius (1.8 degreesFahrenheit) in periods of less than 50years,” Ramírez added.A joint study by the NationalMeteorological Institute and the committeeis showing a consistent pattern of increasinglywarmer nights in Costa Rica andCentral America in the last 30 years –although results won’t be released for anotherthree months.Increased global warming results froma change in the retention of energy inatmospheric gases – a condition attributedto human activity, according to meteorologistRoberto Villalobos, from the meteorologicalinstitute.“As gases like carbon dioxide and nitrogenoxide accumulate and retain more heat,they generate climatic changes,” he said.IN 1987, approximately 50 of the 174species of amphibians in Costa Rica underwenta severe population crash that mayhave been caused in part by global warming.Frog fauna in Monteverde wasreduced by almost 40% and 20 specieswent missing, Pounds said.“The 1986-87 ‘El Niño’ effect, combinedwith a long-term global warmingtrend, brought on particularly warm conditionsthat year,” he said.“Climate change makes (amphibian)populations more vulnerable to disease,particularly to chytrid fungus, a type offungus that grows on their skin,” saidPounds, a U.S. citizen who has become anaturalized Costa Rican.IN 2003, the harlequin frog surprisedexperts with what some have called a“reappearance” at the RainmakerConservation Project near the centralPacific town of Parrita.According to the daily Al Día, the harlequinfrog was believed extinct until twoU.S. researchers identified it at Rainmaker.However, according to frog expertPounds, fairly recent DNA evidence suggeststhe “Rainmaker” harlequin(Atelopus varius) is a lowland speciesthat does not belong to the same speciesas the extinct Monteverde harlequin(Atelopus sp.), whose scientific namemeans “in progress.”CLIMATE change also appears toaffect many other species.“Changes in birds, reptiles and plantscorrelate to climatic changes. Species infoothills are moving up mountain slopesseeking lower temperatures,” Pounds said.The biologist cited the example of thekeel- or rainbow-billed toucan (Ramphastossulfuratus) not native to the cloud forestthat moved there apparently seeking thecooler temperatures.While some animals are able to adaptto new conditions, many cannot. Poundssaid a study of more than 1,000 speciesfrom around the world predicts one fourthcould disappear because of global warmingby the year 2050.

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