Trump Opens 1.3 Million km² of Pacific Marine Monuments to Commercial Fishing in Unprecedented Rollback

US President Donald Trump signed an executive proclamation on 11 June 2026 rolling back commercial fishing protections across approximately 1.3 million square kilometres of Pacific marine national monuments, including portions of Rose Atoll, Mariana Trench, and Papahānaumokuākea, following a similar proclamation in April 2025 that opened the Pacific Islands Heritage Marine National Monument to industrial fishing. The combined proclamations affect nearly 3.1 million square kilometres of protected Pacific ocean, allowing industrial longline and purse seine fishing in areas conservationists warn are critical habitats for threatened sea turtles, whales, dolphins, seabirds, sharks, and endemic fish species found nowhere else on Earth.

 

Scale and Method of the Rollback

 

The June 2026 proclamation targets three additional marine national monuments that together cover nearly 1.8 million square kilometres of coral atolls, deep-sea trenches, and remote islands. The industrial fishing methods that would be permitted in the newly opened areas include longlines carrying kilometres of baited hooks and purse seine nets extending more than 2,000 metres in length, both of which are highly effective at catching tuna, the target species, and generate substantial bycatch across a wide range of marine life. The proclamation frames the rollback as promoting economic opportunity, though conservation organisations and Native Hawaiian cultural groups have characterised it as opening the door to overfishing in a crucially important and culturally significant marine habitat. All the monuments in question were established under the Antiquities Act by previous US presidents, and Trump is the first president to claim authority under the 1906 legislation to remove rather than create monument protections.

 

Constitutional Challenge and the Antiquities Act Question

 

The constitutionality of the proclamation is being challenged by environmental law nonprofit Earthjustice, which has argued that the Antiquities Act functions as a one-way ratchet authorising presidents to create national monuments and protect their resources but not to strip existing protections. Earthjustice lawyer David Henkin has stated explicitly that this specific legal question has not yet been resolved by the courts, making the June proclamation the subject of active litigation that could determine the boundaries of presidential authority over monument management for decades. The outcome of the constitutional challenge will have implications well beyond the Pacific monuments specifically, since it will establish or reject the precedent that a sitting president can unilaterally reverse monument designations made by predecessors under the same legislation.

 

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Cultural and Ecological Stakes at Papahānaumokuākea

 

The Papahānaumokuākea Marine National Monument carries particular significance because it is both a UNESCO World Heritage Site and a sacred place for Native Hawaiians. Kekuewa Kikiloi, co-chair of the Papahānaumokuākea Native Hawaiian Cultural Working Group, has described the monument as a point from which all life springs in Native Hawaiian belief and to which spirits return after death, and has stated that the proclamation undermines two decades of public and stakeholder effort to protect this region. The cultural dimension of the rollback places it within a broader pattern of tension between the Trump administration's resource extraction agenda and the rights and interests of indigenous communities in areas designated as protected precisely because of their ecological and cultural significance. Kikiloi has committed to fighting the proclamation in court alongside the existing Earthjustice constitutional challenge.

 

Implications for Pacific Marine Biodiversity and Global Conservation

 

The opening of these monuments to commercial fishing represents one of the most significant reversals of marine protected area policy in US history and carries implications that extend beyond American waters. Pacific marine monuments protect some of the most ecologically intact and biologically diverse ocean environments remaining on Earth, including species endemic to these remote systems that have no other refuge if these habitats are degraded. Conservationists warn that introducing industrial fishing into these areas risks the same dynamics that have depleted fish stocks in accessible Pacific fishing grounds, including bycatch mortality of non-target species and disruption of the food web dynamics that sustain the ecosystems' exceptional biodiversity. For the international community working toward the 30 by 30 ocean protection target, the US rollback represents a significant step in the wrong direction at a time when expanding rather than contracting marine protection is the stated global ambition.