29 listed as endangered, threatened species in the CNMI

04/10/25 - The CNMI Division of Fish and Wildlife recently disclosed that 29 resident species in the Northern Marianas are currently protected under the U.S. Endangered Species Act.

Those that are endangered include the following:

• Sheath-tailed Bat or Payesyes (Emballonura semicaudata)

• Nightingale Reed-Warbler or Gaga Karisu (Acrocephalus luscinia)

• Mariana Swiftlet or Chachaguak (Aerodramus bartschi)

• Mariana Crow or Aga (Corvus kubaryi)

• Mariana Common Moorhen or Pulattat Gallinula (chloropus guami)

• Micronesian Megapode or Sasangat (Megapodius laperouse)

• Rota Bridled White-eye or Nosa Luta (Zosterops rotensis)

• Slevin Skink (Emoia slevini)

• Hawksbill Turtle or Haggan (Karai)

• Mariana Eight-spot Butterfly (Hypolimnas octocula marianensi)

• Mariana Wandering Butterfly (Vagrans egistina)

• Rota Blue Damselfly (Ischnura luta)

• Humped tree snail (Partula gibba)

• Langford's tree snail (Partula langfordi)

• Fragile tree snail (Samoana fragilis)

• Fire tree or Hayun lagu/ Tronkon guafi (Serianthes nelsonii) 

• Osmoxylon mariannense 

• Nesogenes rotensis

• Ufa-halomtano (Heritiera longipetiolata)

• Solanum guamense 

Those that are threatened include the following:

• Mariana Fruit Bat or Fanihi (Pteropus mariannus mariannus)

• Green Sea Turtle or Haggan (Chelonia mydas)

• Bulbophyllum guamense

• Fadang (Cycas micronesica)

• Dendrobium guamense

• Maesa walkeri

• Nervilia jacksoniae

• Tabernaemontana rotensis 

• Tuberolabium guamense

Carey Demapan, Endangered Species Program manager, said DFW is actively engaged in a variety of projects aimed at enhancing the recovery of these species, focusing on population monitoring, habitat restoration, and the mitigation of threats.

“In relation to mammals (bats), we monitor their population on Saipan, Tinian, and Rota and provide rehabilitation care for injured bats until they can be released. In relation to birds, DFW conducts comprehensive monitoring for all bird populations on Saipan, Tinian, and Rota and has several special projects for certain species.”

Notably, Demapan said DFW created and instituted the Marianas Avifauna Conservation Plan, which lays out their goal of creating redundant populations of CNMI birds to protect against the threat of the brown tree snake. 

“The Rota Bridled White Eye, Nightingale Reed Warbler, and Mariana Crow are species we hope to benefit through this program in the future. Numerous non-listed native birds have already been successfully translocated up to northern islands of the CNMI, including the Rufous fantail, Saipan golden white-eye, Bridled white-eye, and the White-throated ground dove.”

Furthermore, she said DFW works with a sub-awardee to conduct long-term population and nest monitoring of the Mariana Crow on Rota. This project aims to understand and address factors that contribute to the species decline. The sub-awardee also receives additional support, not from DFW, to conduct captive rear and release of crow chicks to increase their population.

On Tinian, DFW is launching a project to investigate the nesting ecology of the Mariana Common Moorhen to study the cause of nest failures. They also have another project on Managaha Island to deploy artificial nest burrows for shearwater birds. 

Lastly, a “Bioinventory” for all listed and locally protected species is conducted every 10 years by DFW to assess the status of wildlife populations and their habitat. Aside from this, Demapan said efforts are also done to control invasive predators, such as rats, in bird habitats.

In relation to reptiles, DFW has a long-term sea turtle monitoring program that conducts weekly surveys on main nesting beaches on Saipan. At the beach, they are looking for signs of turtle nesting activities and when present, DFW conducts nest inventories. 

“This data allows us to assess and estimate the CNMI’s nesting population on a yearly basis. Rapid beach assessments are done twice a year on Tinian and Rota. Our staff’s presence on beaches also protects sea turtles by preventing illegal harvesting from occurring. In relation to the endangered Slevin’s skink, DFW plans to do a habitat study in Sarigan to estimate their population and habitat needs.”

In relation to invertebrates, DFW is actively monitoring snail colonies and conducting invasive predator control/removals of rats and flatworms.  

In relation to plants, many of the species listed are found on Rota. Therefore, on Rota, Demapan said DFW conducts propagation and outplanting for the following species: Serianthes nelsonii, Osmoxylon mariannense, Nesogenes rotensis, Heritiera longipetiolata, Maesa walkeri, and Tabernaemontana rotensis. 

Cycas micronesica will be incorporated in fiscal year 2026. She said propagation and outplanting generally involves seed collection, site maintenance, propagation in the nursery, and outplanting once an appropriate size is reached. In the field, we also fence some endangered plants to prevent grazing from ungulates and apply pesticides, or other natural oils, to manage infestations.  

“Aside from all this, our agency conducts educational outreach in schools, public events, and through social media to share about our work and the importance of these federally listed species. We also review scientific research applications, and issue licenses when approved, for external parties to conduct research in the CNMI. One purpose of this license is to ensure activities do not impact threatened or endangered species, their habitats, or introduce anything harmful in the environment.”

To note, Demapan said, many of these listed endangered species have recovery plans made by the U.S. Fish and Wildlife Service.  The recovery plan serves as a checklist on how species can be delisted from the ESA—it outlines specific tasks required to restore and secure self-sustaining wild populations.

Story by Mark Rabago