The 65-year-old, who used to run an animal feed business, originally took photographs of birds and is now a key figure in the world of Colombian butterflies. Jaramillo is the co-author of an inventory that led to Colombia being recognized as having the widest variety of butterfly species in the world.
The list he worked on was published in the British Natural History Museum in London – which has the world's largest collection of butterflies – in June. The Checklist of Colombian Butterflies identifies 3,642 different species in the Andean country, which makes up 19.4% of the known global varieties.
But Jaramillo is keen to point out he is not a collector.
Like bees, butterflies are pollinators vital to the ecosystem. They are also an important source of food for birds and snakes. Yet their habitats are under threat from deforestation, agriculture and global warming.
Jaramillo, who lives in the southwestern Antioquia department of Columbia, has an archive of 220,000 photos of butterflies and has captured images of 1,500 different species.
The signing of a historic 2016 peace accord between the government and the Marxist guerrilla Revolutionary Armed Forces of Colombia after more than half a century of armed conflict sparked hope areas previously off-limits would become safe for scientists and naturalists. But it was not long before armed rebels and drug-traffickers returned.
"I want to go to many places but there are some I don't go to out of fear," said Jaramillo.
When he does venture out, Jaramillo takes with him a camera, tripod and a container of pink liquid he prepares every morning: shrimp bait. Having tried various other types of bait, he found shrimp bait worked best.
He spreads the foul-smelling bait on rocks and leaves by a rushing stream, and even lays out cotton balls soaked in the liquid.
"That's how I make them think it's bird droppings. When the butterflies land on a leaf they stay there for quite some time ... they're almost like models," he explained. "Without the bait, it would be impossible to see certain species in the woodland because they live in very tall trees."
Another potential barrier is the weather.
"If there's no sun, there are no butterflies."
"In Colombia, I think there are about twice as many species of butterflies as birds," American Kim Garwood, Jaramillo's fellow inventory author, told AFP.
"In the Andes, I have been told there is about 10%-15% of the (world's) butterfly species that is (yet) undescribed. We have many photos of undescribed species."