Check out this essay from our 2025 graduate intern, Elizabeth Allen. She supported several critical projects on Hawaiʻi Island, including marine debris removal in Kaʻū, coastline surveys, native seed collection, invasive species control, and anchialine pool restoration projects. We really enjoyed working with you, Elizabeth!
My name is Elizabeth Allen, and I’m a graduate student in the Tropical Conservation Biology and Environmental Science program at the University of Hawaiʻi at Hilo. For my master’s degree, I completed a series of internships with conservation organizations across Hawaiʻi Island, working my way from montane rainforest all the way down to the coast.
HWF graduate intern, Elizabeth Allen, contributed to several coastal conservation and management projects. PC: University of Hawaiʻi at Hilo
Hawaiʻi Wildlife Fund was a natural fit for me because of its hands-on, community-driven approach to protecting the places and species that make this island so special. I was immediately drawn to HWF’s work with anchialine pools, which are unique ecosystems I had never encountered before, and quickly became fascinated by. These landlocked ponds are fed entirely by groundwater seeping up through porous volcanic rock, which means they have no surface connection to any river or the ocean. Hawaiʻi Island is home to the highest concentration of anchialine pools in the world, and they support some truly one-of-a-kind wildlife, including the ʻōpaeʻula, a tiny red shrimp found nowhere else on Earth.
Unfortunately, invasive fish like guppies and tilapia have taken over many of these pools, preying on the ʻōpaeʻula and throwing the whole ecosystem out of balance. That’s where Hawaiʻi Wildlife Fund comes in, and where I got to help. My favorite project was removing invasive fish from the Kaʻelehuluhulu pools at Kekaha Kai State Park and the Waiaʻelepī pools in Kīholo with HWF’s partner organizations. We used a method called CO2 diffusion: we pumped carbon dioxide gas into the water, covered the pool with a tarp, and waited about an hour until the drop in pH caused the fish to become sluggish enough to scoop out by hand net. It’s a little unconventional, but it works well, since these fish are too tiny and quick to catch without sedating them.
We caught around 440 fish in one day at Kaʻelehuluhulu, and about 6,000 fish over two days from Waiaʻelepī! The best part was seeing the regeneration of the ecosystems. At Kaʻelehuluhulu, ʻōpaeʻula started appearing at the surface again just a week and a half after the second treatment. They had been hiding in the underground passages of the pool the whole time, staying out of sight to avoid the fish, so they came right back once the predators were gone. It was one of the most rewarding things I’ve ever witnessed in my work in conservation.
Elizabeth Allen (and other partners) participate in invasive fish removal at Kaʻelehuluhulu pool at Kekaha Kai State Park. PC: Hawaiʻi Wildlife Fund
Removal of invasive fish at Kaʻelehuluhulu pool at Keakaha Kai State Park using a CO2 diffusion technique. PC: Hawaiʻi Wildlife Fund
I also got to support Hawaiʻi Wildlife Fund’s community beach cleanup days in Kaʻū, where local volunteers and student groups come to remove staggering quantities of marine debris from one of Hawaiʻi Island’s most remote coastlines. Ocean current patterns funnel enormous amounts of plastic waste onto this shoreline from the Great Pacific Garbage Patch, and without regular cleanups, debris piles up rapidly, posing serious hazards for seabirds, sea turtles, monk seals, and other marine life. Seeing people of all ages and backgrounds show up and care so deeply for this place reminded me why this work matters.
The young of invasive fish, including guppies and tilapia, are extremely small, making removal a significant challenge. PC: Elizabeth Allen
This internship taught me that Hawaiʻi’s ecosystems are resilient, but they need our mālama. Mahalo to Megan Lamson and the whole Hawaiʻi Wildlife Fund ʻohana for welcoming me into this work! I’m so grateful for everything I learned.
Elizabeth Allen successfully defended her Master’s thesis at the University of Hawaiʻi at Hilo Tropical Conservation Biology and Environmental Science program in March 2026. Congratulations, Elizabeth!
