The First Circuit affirmed summary judgment for the Bureau of Ocean Energy Management (BOEM) and NMFS in a challenge to BOEM's approval for construction of a wind power project off the coast of Massachusetts. A group of Nantucket residents argued NMFS violated the ESA by issuing a deficient biological opinion (BiOp) about the project's effects on the critically endangered North Atlantic right whale, and that BOEM violated NEPA by relying on NMFS' allegedly defective BiOp. The court disagreed, finding the agencies followed the law in analyzing the right whale's current status and environmental baseline, the likely effects of the project on the right whale, and the efficacy of measures to mitigate those effects. Further, the agencies' analyses rationally supported their conclusion that the project would not likely jeopardize the whale's continued existence. It affirmed summary judgment for the agencies.

A district court denied policy groups' request to preliminarily enjoin construction of a wind energy project off the coast of Virginia. The groups argued the project should be enjoined until NMFS updates its biological opinion to include an analysis of the cumulative effects of other offshore wind projects on the endangered North Atlantic right whale. The court found the groups established a substantial likelihood of standing, but failed to demonstrate that they would suffer irreparable harm absent an injunction. It denied the groups' motion for preliminary injunction.

The Fifth Circuit rejected an environmental group's challenge to the Louisiana Department of Environmental Quality's (LDEQ's) decision to issue preconstruction permits for a liquefied natural gas export facility in Cameron Parish. The group sought to have LDEQ's decision vacated, arguing the facility's emissions would exceed NAAQS and that LDEQ failed to require the facility to use the best available control technology to limit those emissions. The court found that LDEQ's use of significant impact levels in its analysis of potential NAAQS violations was not improper, and that the Department considered all the relevant factors and articulated reasons for its decisions regarding technologies to limit emissions. It further found LDEQ satisfied its public trust duty when issuing the permits. The court denied the group's petition and affirmed LDEQ's permitting decision.

A district court granted New York City's motion to remand to state court a climate deception lawsuit brought against fossil fuel companies. The city initially sued the companies in state court, arguing they violated the city's consumer protection law by misleading consumers about the impact of their products on the climate and falsely representing themselves as corporate leaders in the fight against climate change. The companies removed the suit to federal court based on federal common law, federal officer removal, federal enclave jurisdiction, diversity jurisdiction, Class Action Fairness Act, and Grable jurisdiction grounds. The court found none of these grounds justified removal, joining "the overwhelming majority of federal district and circuit courts around the country to conclude that these municipal law claims belong in state court." It granted the city's motion to remand.

The Ninth Circuit granted the Biden Administration's mandamus petition to dismiss an ongoing climate change lawsuit brought by 21 young people. Plaintiffs initially argued that the U.S. government, by failing to adequately respond to the threat of climate change, violated a "right to a stable climate system that can sustain human life." The appellate court had held plaintiffs lacked standing and remanded to the district court with instructions to dismiss. The district court allowed plaintiffs to amend their complaint, concluding it was not expressly precluded and holding that an intervening authority compelled a different result, and the government again moved to dismiss. The district court denied the motion, and the government petitioned for mandamus seeking to enforce the appellate court's earlier mandate. The appellate court found that neither the mandate's letter nor its spirit left room for amendment, and that nothing in Uzuegbunam v. Preczewski, 141 S. Ct. 792, 796 (2021), changed the law with respect to prospective relief, which was the only relief sought. It instructed the district court to dismiss the suit for lack of standing, without leave to amend.

The Ninth Circuit affirmed in part and vacated in part a district court's preliminary injunction limiting wolf trapping and snaring in certain parts of Montana to January 1, 2024, through February 15, 2024. Nonprofit groups argued Montana's laws authorizing recreational wolf and coyote trapping and snaring allowed unlawful "take" of grizzly bears, a threatened species, in violation of ESA §9. The district court granted the groups' motion for a preliminary injunction. The appellate court found the district court did not abuse its discretion in finding serious questions going to the merits, and affirmed its finding of a reasonably certain threat of imminent harm to the bears had the state's wolf trapping and snaring season proceeded as planned. It affirmed the temporal scope of the injunction, but held it was geographically overbroad and remanded for the district court to reconsider the geographic scope. It further held the injunction was overbroad because it prevented Montana from trapping and snaring wolves for research, vacated that portion of the injunction, and remanded for the district court to make proper modification to the scope of its order.

A district court granted in part and denied in part summary judgment for a conservation group in a challenge to NMFS' management of the Pacific sardine under the Magnuson-Stevens Act (MSA) and NEPA. The group argued NMFS' plan to rebuild the sardine population after it was declared overfished in 2019 violated the MSA and NEPA. With respect to the MSA claims, the court found NMFS' rebuilding target did not fail to use the best available science and its determination that its 2023-2024 specifications required no essential fish habitat consultation was neither arbitrary nor capricious; but that the 2023-2024 specifications violated the MSA because they did not set catch limits that would rebuild the population within the statutory time frame, and that NMFS failed to demonstrate it relied on the best available science to set the overfishing limits or that the 2023-2024 specifications would prevent overfishing. With respect to the NEPA claims, the court found NMFS failed to take the requisite "hard look" because it relied on inconsistent assumptions and ignored important aspects of the proposed plans under consideration, and that it failed to take a hard look at the impact on the endangered humpback whale. It granted in part and denied in part summary judgment for the group.

A district court denied the Biden Administration's motion to stay an ongoing climate change lawsuit brought by 21 young people. The U.S. government argued the suit must be stayed because there was a substantial likelihood the Ninth Circuit would grant its petition for mandamus. The court found the government did not meet its burden to show a likelihood of success on the merits necessary to support its motion because (1) it had other means, such as a direct appeal, to obtain the desired relief; (2) it did not address its own conduct delaying the normal course of litigation—including 14 motions to stay—and its request would only lead to more judicial waste; and (3) it did not show that the district court erred when it granted plaintiffs' previous motion for leave to amend. Further, it could not discern any public interest in supporting the motion because the government had repeatedly delayed the suit from reaching the evidentiary phase for nearly 10 years, and granting a stay would only add to this delay. The court denied the motion.

The D.C. Circuit affirmed summary judgment for the Army Corps of Engineers and NMFS in a challenge to approval of a dredging project in Puerto Rico's San Juan Bay. Environmental groups argued the agencies failed to take the necessary "hard look" at the project's environmental effect. The district court granted summary judgment for the agencies, concluding they did not act arbitrarily, capriciously, or contrary to any environmental statute in fulfilling their obligations to examine environmental impacts. The appellate court affirmed, finding the agencies adequately considered the project's cumulative impacts, how it would affect minority and low-income communities, and its impact on threatened coral species.

The Third Circuit denied power companies' petition to review EPA's issuance of a federal implementation plan (FIP) establishing nitrogen oxide (NOx) emission limits for selective catalytic reduction-equipped coal-fired electric generating units in Pennsylvania to address reasonably available control technology (RACT) requirements for the 1997 and 2008 ozone NAAQS. The companies argued EPA exceeded its authority under the CAA by promulgating the FIP before approving or disapproving a SIP issued by the Commonwealth, and that the FIP was arbitrary and capricious because EPA's calculations for NOx limits relied on unsupported assumptions and failed to meet RACT standards. The court found the plain language of the CAA did not require EPA to act on the SIP before issuing the FIP, and that the Agency articulated a rational basis for its calculations. It upheld the FIP and denied the petition.