Interior Secretary Ryan Zinke did not immediately release a report Thursday on his recommendations for the fate of 27 national monuments, including Bears Ears National Monument in Utah/BLM, Bob Wick

Editor's note: This updates with additional reaction to lack of details from Interior Department on monument recommendations.

Interior Secretary Ryan Zinke's decision Thursday not to publicly release details of his recommendations to President Trump on the status of 21 national monuments drew strong condemnation and generated immense speculation into what he had decided.

The Interior secretary was in Montana on Thursday to discuss wildland firefighting demands and his office released a brief two-page summary of his findings. The summary did not, however, include any of his recommendations for the national monuments.

That brevity drew a flurry of statements from conservation and environmental groups opposed to the monument review requested back in April by President Trump.

"To recommend diminishing the size of just one national monument is one too many. And it opens the door to allow mining, oil and gas and other destructive development. This could be a devastating blow for all Americans, and our lands and waters that are so deserving of protection," said Theresa Pierno, president and CEO of the National Parks Conservation Association.

“These are our public lands, and the public deserves to know what the administration plans to do with them,” addeds Whit Fosburgh, president and CEO of the Theodore Roosevelt Conservation Partnership. “These recommendations have the potential to impact the future of world-class hunting and fishing on some of America’s finest public lands and set a precedent for the future status of all national monuments, even those created by Theodore Roosevelt in 1906—but we won’t know until the results of this public process are made public.”

In his summary report (attached below), Secretary Zinke maintained that President Trump has "the authority to review and consider recommendations to modify or add a monument," and he held that its use by recent presidents has been "arbitrary or likely politically motivated or boundaries could not be supported by science or reasons of practical resource management."

"Comments received were overwhelmingly in favor of maintaining existing monuments and demonstrated a well-orchestrated national campaign organized by multiple organizations," the summary concluded without citing any specific monument recommendations. "Opponents of monuments primarily supported rescinding or modifying the existing monuments to protect traditional multiple use, and those most concerned were often local residents associated with industries such as grazing, timber production, mining, hunting and fishing, and motorized recreation."

Mr. Fosburgh, noting that the secretary's summary made mention that past monument designations have resulted in "restrict(ing) public access, prevent(ing) hunting and fishing," pointed out that "22 of the 27 monuments reviewed are open to hunting and fishing and a number were created with the active support of sportsmen and women."

At Defenders of Wildlife, President Jamie Rappaport Clark said that, “Secretary Zinke’s apparent decision to roll back protections for national monuments and his failure to disclose the details of that decision is monumentally out of touch with the will of the American people. We have a right to know how he intends to change monument designations, and which of these special places are at risk. He’s ignoring millions of comments imploring the Trump administration to safeguard these lands and the wildlife living within their boundaries."

House Natural Resources Committee Chairman Rob Bishop, R-Utah, meanwhile, said there needed to be changes in the "process" presidents followed in wielding the Antiquities Act that grants them the authority to designate monuments. Yet while the congressman long has voiced frustration with the act, during a nearly 40-minute phone call with reporters he never specified what changes he would recommend.

The speculation over what Secretary Zinke might or might not recommend to President Trump, who has called his most recent predecessors' use of the Antiquities Act an "egregious abuse of federal power," led conservation groups to jump on an Associated Press report in which Secretary Zinke said some changes to some monuments would be suggested, but that he would not recommend that any be abolished.

In Maine, meanwhile, the Bangor Daily News reported that "nothing dramatic" would be suggested for Katahdin Woods and Waters National Monument, a statement which adheres to what the Interior secretary said after visiting the monument in June.

Mr. Trump directed his Interior secretary back in April to begin a review of 27 national monuments designated by the last three presidents, going back to 1996 when President Bill Clinton established the Grand Staircase-Escalante National Monument in Utah via his authority under the Antiquities Act. At the time, Secretary Zinke said the executive order would not abolish any monuments and would not weaken any environmental regulations, but was designed to review how the Antiquities Act has been used.

Since he started his review in May, the Interior secretary visited just eight of the 27 national monuments on his list. During those travels, Secretary Zinke said he engaged in "more than 60 meetings with hundreds of advocates and opponents of monument designations, tours of monuments conducted over air, foot, car, and horseback (including a virtual tour of a marine monument), and a thorough review of more than 2.4 million public comments submitted" to the Interior Department.

While the draft report released Thursday didn't contain any specific recommendations, Secretary Zinke previously has said he would recommend:

• Reductions in the size of Bears Ears National Monument in Utah
• No changes to the Sand to Snow National Monument in California
• No changes to Craters of the Moon National Monument and Preserve in Idaho
• No changes to the Hanford Reach National Monument in Washington state
• No changes to the Grand Canyon-Parashant National Monument in Arizona
• No changes to the Upper Missouri River Breaks National Monument in Montana, and;
• No changes to Canyons of the Ancients in Colorado

Secretary Zinke has also suggested that Katahdin Woods and Waters National Monument in Maine would make a good national park.

Meanwhile, various groups Thursday condemned what they thought the report might call for.

“Any recommendation from Secretary Zinke to shrink national monuments is hypocritical at best and ruinous at worst. Secretary Zinke claims to support public lands, but now we know he’s just one more Trump Administration stooge for polluting special interests," said Sierra Club Executive Director Michael Brune in prepared statement. "Whether the preservation of Native American sacred sites or a natural wonder of the world, public lands and waters are granted monument status for a reason. Stripping these places of that recognition devalues the diverse history they preserve, the outdoor economy they support, and the future they offer."

At Friends of the Earth, Ben Schreiber, said, "Today’s announcement is another in a long line of blatant handouts to the oil and gas industry. If Secretary Zinke recommends shrinking Bears Ears National Monument it will be another slap in the face to Native American tribes who lobbied for years to get it designated as a National Monument. This follows on the heels of Trump’s approval of the Dakota Access Pipeline despite strong tribal opposition. Zinke’s action is illegal and he can rest assured that his latest giveaway to corporate polluters will be litigated in the courts."

Rep. Bishop, meanwhile, said the Antiquities Act long has been wielded for political, not conservation, purposes and that it needs to be modified in some way to improve the "process" of considering public lands for monument designation. As for Secretary Zinke's review of 27 national monuments, which President Trump directed in April via an executive order, the Republican congressman said the issue wasn't between conservation and energy development but simply process.

"The real issue here isn't the ability to create or modify national monuments," Mr. Bishop said. "The issue is Congress never intended for one individual to be given the power to unilaterally dictate land management policies for enormous swaths of public lands. This is about the rule of law, whether we as a country adhere to the clear language and intent of the law, or whether we allow the Executive Branch to simply make up the rules as it goes along. This is about people as well, and the impact of an increasingly larger and restricted monument designation on the people who feel that their voices and perspectives have been ignored in the process.

"... It is about process. There are outside special interest groups that are spending tremendous amounts of money to blur the lines between antiquities and other areas of federal lands and their designations. I've repeatedly heard groups that are misleading the public that somehow this is a conflict between conservation and energy development. It's simply not true."

Despite his past outspoken criticism of the Antiquities Act, near the end of his call Rep. Bishop stated that, "We don't need to eliminate the Antiquities Act totally. We just need to go back to what it's purpose was, to protect an object that was in imminent danger until we have a chance to make some rational approaches on how we do it. And that we should be dealing with objects of antiquity, not large landscape viewsheds."

After the call, a spokeswoman for Mr. Bishop, when asked what he specifically wanted to see altered in the Antiquities Act, said the congressman wants it "realigned with its intended purpose by setting reasonable limits on future use. We must ensure the act is being used to protect antiquities. We need to ensure reasonable continued public access to monuments. We must ensure transparency and insist that local perspectives are included in land managmenet decisions."