January 3, 2020
Lee Brann

From fewer than 30 to now around 3,000, the world’s rarest goose is on the rise! Owing to a decades-long recovery effort, the Hawaii state bird has rebounded from its near extinction in the mid-twentieth century. To prevent its extinction, the nēnē was among the first species to receive protections with the Class of '67 and was listed as endangered when the Endangered Species Act (ESA) was signed in 1973. Now with its rebounding numbers, the Fish and Wildlife Service (FWS) recently downlisted its status from ‘endangered’ to ‘threatened’ - a far less dire designation and evidence of the value of the ESA’s protections. 

Team of nēnē
Gary Kramer

The nēnē’s recovery required an immense effort, spanning decades, by state and federal agencies, national parks, nonprofits, and private landowners. Much of the credit goes to a captive breeding program that started in 1949 and ended in 2011, introducing some 2,800 captive-bred nēnē to the Hawaiian Islands. This reintroduction succeeded only because a diverse network of conservation organizations and individuals also took steps to manage the nēnē’s habitat and keep predators at bay, providing the conditions the newly introduced birds needed to survive. The ESA, with its protections and requirements, was the catalyst behind many of these heroic efforts.

Nēnē, Branta sandvicensis, an endangered endemic bird in Hawai`i. - Hawai‘i Volcanoes National Park
Kathleen Misajon/NPS

At Defenders, we look towards 2020 as a year filled with optimism and believe this new development offers cautious hope for the nēnē. The improved status of the species shines as an ESA success story and shows the tremendous role ESA protections play in restoring even the most troubled species. But the nēnē’s path to recovery also highlights the need to maintain protective measures beyond the initial celebration of downlisting. Several threats (for example, habitat degradation from human development and nonnative species; parasitic and viral disease; and predation by nonnatives like mongooses, cats, and pigs) continue to imperil the species. 

In fact, the nēnē’s struggles are in many ways representative of Hawaii’s unique endangered species crisis. Among all US states, Hawaii has the greatest number of species listed on the endangered species list. Ninety percent of native Hawaii species, including the nēnē, are endemic - found only in Hawaii and adapted to its unique island conditions. This trait often makes them especially vulnerable to novel threats like invasive species (since many evolved with few or no predators) and habitat alteration and more reliant on ongoing conservation efforts. Scientists regard the nēnē and many other Hawaii species as ‘conservation-reliant species’, meaning they require ongoing management to prevent extinction even after they have reached a sustainable population size. Wildlife conservation in Hawaii is no simple task. 

Pair of nēnē in a field
Gary Kramer

For decades, the nēnē received ample care as an ‘endangered’ species under the ESA. But many species listed as ‘threatened’ - the nēnē’s new, less critical designation - have also benefited from strong conservation programs. That is because of what is known as the ‘blanket 4(d) rule,’ a regulation issued in 1975 by the FWS that automatically granted to ‘threatened’ species many of the same protections offered to ‘endangered’ species. The FWS’ aim with this rule was to prevent ‘threatened’ species from declining further toward an ‘endangered’ status. It has been instrumental in the conservation of imperiled species.

The same kind of proactive approach is crucial for the nēnē. Continued recovery - and even the maintenance of the existing nēnē population - means continued habitat management, habitat protection, and predator control. It also means further participation from all stakeholders. Without these measures, the nēnē could be susceptible to losing its hard-won population gains. Fortunately, the nēnē still receives vital protections under its own specific 4(d) rule, an alternative to the blanket 4(d) rule that contains a more tailored set of provisions the FWS can opt to apply in certain cases, that regulates activities potentially damaging to the species - things like agricultural development, recreation, and predator introduction. The lifeline for this ‘conservation-reliant species’ remains largely in place. 

But other species identified as ‘threatened’ may not be so fortunate. In August of 2019, the Trump administration rescinded the blanket 4(d) rule to all species newly designated as ‘threatened’ by FWS. That means many species that become listed as ‘threatened’ may not receive an advanced layer of ESA protection unless they are awarded their own special 4(d) rule, which is by no means guaranteed. We can speculate on what this move might mean for any given species, and there is particular cause for concern about Hawaiian species that may meet the definition of ‘threatened’ somewhere down the road. Smart conservation arrives early and stays late; it does not work if we only start protecting species after they start teetering on the brink of extinction.

Nene, Hawaiian Goose
John and Karen Hollingsworth/USFWS

The rebound of the nēnē calls for celebration and optimism. The ESA and all of the partner organizations working under it that helped put the species on the path toward recovery deserve applause for this success. But it should also draw our attention to the needs of ‘threatened’ species. Decades ago, the FWS embraced proactive and precautionary measures to ensure the conservation of these species through the blanket 4(d) rule. That same attitude of caution is even more fitting today as threats from climate change, invasive species, and habitat degradation escalate. We must work proactively to prevent species from getting to the point where the nēnē once was, with only a couple dozen or so left, before we start to act. The nēnē, and many other Hawaiian species, need our help. They need us to stay ahead of the game.  


Lee Brann

Lee Brann

Endangered Species Policy Intern
Lee works in the Center for Conservation Innovation on issues at the intersection of science and policy, focusing on federal agency implementation of the Endangered Species Act and the application of science in decisions concerning species protections.

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