The wildlife operator in Santa Cruz, and the one with something nobody else has: Jaguarland, a private reserve they run themselves, which is about as close to a reliable jaguar sighting as Bolivia offers. Around it they sell the things the eastern lowlands are actually good for — sloths and birds around the city, full-day birding, Amboró, the Lomas de Arena dunes, the Jesuit missions, the Jardín de las Delicias waterfalls — plus the Zongo Valley birding trip on the other side of the country and the Brazilian Pantanal over the border.
They also sell Uyuni and the Rurrenabaque pampas, but that is not why you would book them. They have held a TripAdvisor Certificate of Excellence since 2014 and describe themselves as the number one operator in Santa Cruz, which for once is a claim about a real specialism.
The office is in Equipetrol and open weekday afternoons only, 3 to 7. Two mobiles; the first is the WhatsApp, and their own links to it are mistyped — use the number, not the button.