Dr. Rivero obtained a Bachelor of Science in Agronomy from the University of Puerto Rico at Mayagüez in 1945.
From 1959 to 1960 he served as director of the Biology Department and from 1962 to 1966, as dean of arts and sciences, oversaw the work of over 200 faculty members and a two million dollar annual budget.
Between 1966 and 1968, he served as a research associate at Harvard University and visiting scientist at the Venezuelan Institute of Scientific Investigation.
In addition to founding the Mayagüez Zoo, Puerto Rico's only zoological garden, it was named after him in 1998.
He was the founder and first president of the Puerto Rico Zoological Society, as well as of the Association of Island Marine Laboratories.