researcher rafael reina has set up motion-triggered cameras at ten sites like this. he wants to know exactly which animals -- whether bird species, tapirs, or jaguars -- come to drink, and how often, and how their numbers change from year to year. there are only 450 jaguars left here. rafael: many endangered species depend on these watering holes, which are e impermanent and unpredictable. some years they're full, in others they dry up. every time we investigate, it's clear how important they are for wild and threatened d animals. reporter: reina has the support of the g.i.z., a german development agency. g.i.z. provides cross-border financing of various long-term studies, and coordinates projects in guatemala, belize, and mexico. florian: data has to be made more freely available, including across bororders. that's where we have a lot of potential to affect change with our project. reporter: the goal -- providing cross-border biodiversity conservation in the selva maya. in mexico, the g.i.z. has equipped park rangers with digital smart technology. the software works