Donald Trump’s latest fishing order is raising new concerns about US marine protections, as it directs federal agencies to prioritize recreational fishing while reconsidering the scientific standards and environmental regulations that govern American fisheries.

The National Marine Fisheries Service hailed last Thursday’s order, Restoring American Saltwater Angling and Recreation, telling the Guardian: “By addressing long-standing flaws in federal data collection, streamlining permitting, and expanding marine habitats, this action delivers long-overdue stability to America’s $1.2tn outdoor recreation economy.”

However, conservation advocates say the order marks another step by the Trump administration away from science-based marine management and conservation.

“That progress is now being dismantled, bit by bit,” said Lance Morgan, president of the Marine Conservation Institute, adding: “The current administration has moved to gut most ocean protections, threatening to take the US from a global leader in marine conservation to nearly a bystander.”

The order directs the commerce department to review fisheries guidelines under the Magnuson-Stevens Act, the primary 1976 law that governs marine fisheries management in US federal waters. The review of the guidelines should “ensure they appropriately account for the … recreational fishery”, the order says.

Gib Brogan, senior campaign director at Oceana, said the review is not inherently unusual. However, according to Brogan, the concern is how the Trump administration could reinterpret the standards.

“The concern comes in the way that this administration has been implementing the bedrock environmental and conservation laws,” Brogan said.

“We’re very concerned about how this administration will attempt to reinterpret things like overfishing and rebuilding, or what constitutes ‘best available science’,” he added, pointing to language used by Trump administration officials.

The order also directs the interior department to establish a program facilitating the conversion of decommissioned offshore oil and gas structures into permanent artificial reefs.

Kristen Monsell, oceans legal director and senior attorney at the Center for Biological Diversity, called the provision “a handout to the oil industry”, saying that it is “another blatant demonstration of Trump’s desire to let the oil industry avoid any responsibility for the mess it continues to leave in our oceans”.

“Offshore platforms were never designed to function as healthy reefs and are known to serve as hubs for invasive species, including non-native corals and fish. They can also leach harmful chemicals into the ocean,” Monsell said.

Meanwhile, Arlo Hemphill, Greenpeace USA’s ocean sanctuaries project lead, said some rigs could provide useful habitat but questioned whether converting them into reefs is appropriate in every location. “You don’t just put [artificial reefs] anywhere just because there happened to be an oil rig there,” he said, pointing to obstacles including rigs located in navigational lanes, areas with strong currents that may be unsuitable for artificial reefs, or places that already have abundant habitat.

Hemphill also cautioned that attracting fish to a structure does not necessarily mean creating new fish populations.

“They do have the potential to build the population by creating new habitats. But the first fish you’re going to see are not fish that were created by that habitat being there. It’s fish that were in all the surrounding area and then were drawn in by … a new habitat … It’s just making them easier to catch,” he said.

The order also calls for the establishment of an “Interagency Shark and Pinniped Depredation Task Force” to address cases where sharks and marine mammals take fish from anglers’ lines.

The taskforce is directed to examine barriers to shark fisheries, including international agreements and listings under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).

Andrea Treece, deputy managing attorney for oceans at Earthjustice, said the provision appears aimed at easing restrictions on the shark trade, which has been largely prohibited under US federal law.

“It seems to be aimed at killing more sharks and that is really short-sighted,” Treece said, pointing to the critical role sharks play in ocean ecosystems, including regulating food webs and supporting the health of coral reefs.

“Most shark populations in the US are a fraction of what they were before the rise of industrial-scale fishing in the mid 1900s,” Treece said, adding: “To the extent that recreational fishers in some places are experiencing more sharks biting fish off lines, it’s worth asking why that is … We should be looking at, for example, is it that fish and increased recreational fishing numbers are competing for fewer fish?”

“We should be looking at … ways we can actually conserve and foster more abundant fish populations for everybody instead of just killing off the competing predators in the ocean, which is just going to destabilize the system in the end,” she continued.

Grace Casselberry, a postdoctoral shark depredation researcher at the University of Massachusetts Amherst, also urged caution.

“While some shark populations have seen various levels of recovery, we also have more people fishing recreationally than ever before, which creates a perfect storm for these encounters … It has taken decades to get to the point where sharks are beginning to recover, and that progress could be quickly undone,” Casselberry said.

“We must ensure that changes to the current strict harvest limits are based on the best available science and any adjustments continue to promote population growth and sustainability.”

The executive order also directs agencies to “suspend, revise or rescind regulations that overly burden boaters, anglers and outdoor businesses”.

Monsell warned that the order’s deregulatory push could threaten protections such as the vessel-speed rule aimed at reducing deadly collisions between ships and endangered North Atlantic right whales. The measure requires ships to slow to 10 knots or less in certain areas and at certain times, reducing the risk of fatal strikes.

“The speed rule is an effective, life-saving measure that reduces the risk of deadly strikes,” Monsell said, adding: “Right whales are facing threats from all directions, and the speed rule is one of their few protections.”

The executive order is the latest move by the Trump administration to roll back environmental protections and reshape federal marine conservation policy. Since returning to office last year, the administration has expanded deep-sea mining, weakened protections for marine national monuments and dismantled key protections for endangered species across the US.

“If every administration rollback proposed survives legal challenge, US waters could end up with just 4% under any form of protection – down from 26% – a number that is far too small to sustain marine biodiversity,” Morgan said.

“Calling this a science initiative isn’t an improvement, it’s a giveaway of our fish and our ocean ecosystems, dressed up in credible-sounding language,” he added.