National Geographic : 1988 Apr
Tune inSunday, April ~... for a rare view of puffins, curious and little-known seabirds that live in the open seas and return annually to the Atlantic coast to nest. Sunday, April 10, prowl through Minnesota wood- lands as EXPLORER tracks the behavior and interaction of wild black bears. Sunday, April 17, dive to the seafloor where, from a submarine, scientists observe and photograph the elusive six-gill shark. And, Sunday, April 24, soar over the jungle canopy in a tree- top trolley that transforms scientists into arboreal aviators.