Remarks:
This is how W. J. Schaldach Jr., acclaimed Tuxtlas birding authority now deceased,  describes the island:
If the trip to visit Isla Terrón is possible today, ..... we will board our launch to run along the coast, passing numerous basalt
cliffs and headlands where Peregrine Falcons winter (Sept – early May) to arrive at Cape Roca Partida (Split Rock). Just
offshore from the cape (about 1 Km.) is the rocky island we are seeking, in shallow water, surrounded by a coral reef. Here,
on the rocks and low shrubs, five species of sea birds rest: Brown Pelicans, Frigate Birds, Laughing Gulls, Royal Sandwich
and Least Terns. During peak migration periods, flocks of herons, anhingas, Franklins and Bonapartes Gulls, terns and
passerines (including enormous flights of Great – Tailed Grackles) pass over and around us (a glorious spectacle!).

The best times are the months of September and April. The species which nest here do so from March to May, but the frigate
birds and Brown Pelicans nest again from September to November in most years.
Terron Island
significance on the coast of the Sierra de Los Tuxtlas
Located  in San Andrés Tuxtla, west of Roca Partida,  the
island may be visited by charter boat from Arroyo de Lisa
or Toro Prieto.

The small volcanic island is a haven for seabirds and is
uninhabited.