[2] It is a locally common, diurnal species found near fast-flowing small streams and creeks in lowland rainforest.

To attract females and to defend their territories, males of A. franciscus use advertisement calls, not visual displays as typical for Atelopus.

Moreover, this species lacks an external vocal sac, so can only produce low-intensity calls that propagate short distances (<8 m).

Nevertheless, it has a well-developed inner ear and has been shown to respond acoustically to the calls of conspecifics in the field.

[3] Male territories are closely spaced, only 2–4 m apart on average, and despite the handicaps discussed above, acoustic communication appears sufficiently efficient at these short distances.