Waterfall-climbing Fish Showcased in Puerto Rico Study


Photo of Sirajo goby by Patrick Cooney, NC State University


This post is part of a special National Geographic news series on global water issues.

The first comprehensive study of Puerto Rico’s freshwater fishes and their habitat has raised awareness of some “hidden gems that have largely been ignored,” according to researchers from North Carolina State University.

The research is “a huge first step in conserving and protecting these fish and their habitat,” says NC State biology professor Thomas Kwak, who led the study. “Many of these fish are very charismatic — they are unique and really worthy of conservation,” he said in a statement.

For example, Kwak points to Puerto Rico’s native Sirajo goby — “a brilliantly colored fish that has evolved sucker-like pelvic fins that allow it to climb steep waterfalls and even the sheer faces of some artificial dams.”

Puerto-Rico-goby-2.jpgThe study focused on identifying features that support native fish populations, and distinguishing those features that make a system susceptible to invasion by exotic species.

The researchers investigated 81 streams and identified 24 fish species (10 native) and 15 crustacean species (11 shrimp, 3 crabs, 1 crayfish).


The most abundant fish species were Agonostomus monticola (mountain mullet), Poecilia sphenops (Mexican molly), Poecilia reticulata (guppy) and Sicydium plumieri (Sirajo goby).


“The research will likely have a significant impact on how the Puerto Rican government makes decisions on issues ranging from fisheries management to water use and habitat management,” Kwak says.

Kwak also hopes that the study raises the profile of the freshwater fishes in Puerto Rico both on the island itself and abroad as part of Puerto Rico’s natural heritage. “Just letting the world know the fish are there is an accomplishment.”

The Puerto Rico Department of Natural and Environmental Resources funded the research with federal Sport Fish Restoration funds, and an overview of the study was presented at the American Fisheries Society (AFS) Annual Meeting in Ottawa, Canada, earlier this year.

Photos of river goby (top) and Sirajo goby by Patrick Cooney, NC State University


  1. Rob Wegbrands
    July 1, 2014, 7:23 am

    …and I thought I was safe from these critters higher up!! Definitely, not a lizard 🙂

  2. Kayla Tennant
    St. Thomas, U.S Virgin Islands
    November 12, 2013, 11:48 am

    Great this is at there, especially in Puerto Rico. I would love chat! I am a graduate student at UVI in St. Thomas I will be studying these fish species in the ghuts or freshwater streams on St. Thomas! Great pics:)

  3. Victoria
    September 3, 2013, 9:19 am

    This fish is pretty I love that blue that it is. I love pictures of Puerto Rico and I am Puerto Rican . Nice job.

  4. Susan Cooney
    Lake Oswego, OR
    November 10, 2011, 5:59 pm

    Not only great photographs Patrick Cooney, but excellent research that you accomplished in Puerto Rico. Congratulations on being published with National Geographic! Mom