The Rio Grande Valley landscape uniquely blends temperate, subtropical, coastal, and desert habitats, creating one of the most biologically diverse regions in the continental United States. With at least eleven distinct biotic communities, a mix of wildlife converges like nowhere else, as both Central American and North American species migrate here to the edge of their range.

In addition, the diverse assemblage of habitat gives home to many indigenous species, some even federally-listed as threatened or endangered These include mammals such as ocelots and jaguarundis; birds like the brown pelican, bald eagle, northern aplomado falcon, and piping plover; and plants such as the black lace cactus, star cactus, and South Texas ambrosia.