The course of Jose Sarasola's life changed 19 years ago when he first came across a Chaco eagle - one that had been killed by a rancher and hung from a railing as a warning to other birds.
The studies he has carried out since then on that endangered raptor made him one of the recipients of the United Kingdom's prestigious Whitley Awards this year.
But Sarasola told EFE in an interview that he is most satisfied at having played a part in changing community perceptions about this large South American bird of prey.
"It's been very gratifying because when we started working with the eagle there was practically no awareness about it," Sarasola said two months after receiving his so-called "Green Oscar" - and a 40,000-pound ($49,640) cash prize - from Princess Anne at a ceremony at the Royal Geographical Society in London.
Sarasola was recognized there for his nearly two decades of conservation efforts, including going door to door and trying to show the modern day gauchos (ranchers) of central-western Argentina why that bird (Buteogallus coronatus), which is also found in parts of Brazil, Bolivia and Paraguay, should be protected.
The dead eagle he found those many years ago had been placed on a railing by a rancher in La Pampa province as a warning to other birds, who were believed to attack young livestock.
It turned out, however, that the perception of that rancher and many others was false: the gray Chaco eagle, also known as the crowned solitary eagle due to its large occipital crest, hunts around 600 different types of prey but all of them are wild animals.
Local inhabitants, however, thought those birds predated livestock, and that belief persisted - and was passed down by word of mouth from one generation to the next - due to a lack of scientific studies.
Sheep were raised in that region instead of cattle many years ago, "and probably in a given moment of that history eagles hunted newborn sheep," Sarasola said.
Nowadays, many ranchers in La Pampa see conservation as a serious issue and help preserve the eagle, said Sarasola, a native of the provincial capital of Santa Rosa.
Ranchers have stopped shooting the Chaco eagle thanks to the biologist's awareness-raising efforts, with no such deaths registered since 2013.
The main square of Santa Rosa features a sculpture of a Chaco eagle, while that bird serves as the mascot for a local sporting competition. Sarasola said he also learned that a boy scouts club has taken the name Crowned Eagle.
Chaco eagles, however face two other major threats: drowning in tanks that ranchers use to store water in that vast semi-arid region and electrocution on power lines.
"With the money from the prize, we're working with the regional energy administration to change the location of 90 power pylons that represent 20 percent of the electrocution deaths over a 150-kilometer stretch," said Sarasola, a biologist with Argentina's National Scientific and Technical Research Council.
"It's difficult to convince the power companies," Sarasola said, though adding that it is "quite economical" for those firms to make changes such as switching cables or using safer materials.
"We hope the prize helps raise this awareness that doesn't exist yet. In Spain, a company is hit with a huge fine if an eagle dies," said Sarasola, who earned his doctorate at the Doñana Biological Station in the southern part of that Iberian nation. EFE-EPA