Butterflies of Tamaulipas
- Northern Prairie Wildlife Research Center listing of species reported in the state.
- http://www.butterfliesandmoths.org/map?dc=5893&_dcc=1

Grutas de Bustamante (Caves of Bustamante)
- Overview and links to information about the huge cave system just outside of Bustamante.
- http://www.showcaves.com/english/mx/showcaves/Bustamante.html

World Institute for Conservation and Environment (WICE)
- List of resident and migratory birds, with common names in English and Spanish.
- http://www.birdlist.org/nam/mexico/tamaulipas/temaulipas.htm

Gómez Farías Region and El Cielo Biosphere Reserve
- Report on geography, flora and fauna, and cultural setting, from Smithstonian Institute's Centres of Plant Diversity.
- http://www.nmnh.si.edu/botany/projects/cpd/ma/ma9.htm