By Maureen Dietrich

When biologist Sandra Guido is feeling down and out, she heads to her favorite natural sanctuary, the Estero del Yugo. A walk through its three distinct ecosystems of a brackish water lagoon, freshwater basin and low tropical deciduous dry forest is the elixir that refreshes her soul. Her practiced eye scans the forest bed searching for animal tracks or signs of sap awakening in dormant trees. She climbs the observation tower to scour the sky and lagoons for the 200-plus species of birds who call the Estero home. This is her world and she is passionate about sharing it with others. “Twelve years ago,” she says, “there was no preservation plan here. The government didn´t recognize it as a precious wetland and it was going to disappear.” Following a lobbying blitz, the area was given to the Centro de Investigacíon en Alimentación y Desarrollo AC (CIAD) which turned it into a conservation area, building research facilities close by. A natural teacher, Sandra began taking school children on walking tours through the Estero. “We´ve had a long relationship with the Ministry of Education. For me, teenagers are wonderful to work with because they are autonomous