Homeland Security says it’s now apprehending fewer than 1,800 illegal immigrants a day sneaking in across the southern border and President Biden is claiming credit, saying his get-tough changes last month have largely solved the problem.

The numbers are almost low enough to trigger the end of Mr. Biden’s border shutdown proclamation, which he issued in early June and which allowed Homeland Security to tighten asylum rules and to more quickly oust those who try to sneak into the U.S. between the official border crossings.

“Border crossings are lower today than when the previous administration left office,” Mr. Biden said in his speech from the Oval Office on Wednesday, where he explained his decision to quit the presidential race and began an effort to burnish his legacy.

Experts challenged Mr. Biden’s claim, saying he’s parsing his words — and the border numbers — too finely.

“It’s not correct in any sense,” said Andrew R. “Art” Arthur, a former immigration judge and before that head of the government’s immigration national security law division. “What he likely meant to say is Border Patrol apprehensions, but even under that metric it would technically be correct, but it would be factually misleading because it fails to include 1,450 aliens with no visas, no rights to enter the United States, that are being ushered by the Biden-Harris administration into the United States through ports of entry.”

If the numbers drop below an average of 1,500 a day, it could end the emergency border shutdown Mr. Biden imposed in June.

Adam Isacson, a border expert at the Washington Office on Latin America, said there’s about a 50-50 chance that the numbers will drop that low in the coming weeks.

But he said it’s not likely to last.

“What we’ve seen over 10 years of crackdowns is that they bring a short-term drop in migration that eventually bottoms out, usually within a few months, and then numbers recover as migrants and smugglers adjust,” he said.

The debate over the numbers comes at a critical time in politics.

Vice President Kamala Harris is trying to secure support to become the Democrats’ presidential nominee and to campaign against the GOP candidate, former President Donald Trump. Mr. Trump says that her record on the border, where she was tasked with reducing the flow of illegal immigrants rushing for the U.S., should cause voters to reject her.

The improvement in numbers is irrefutable and gives Ms. Harris something to point to.

In December, the worst month in records dating back nearly three decades, Border Patrol agents recorded nearly 250,000 arrests at the southern border, or more than 8,000 a day. In June that dropped to 83,536, or about 2,800 a day. As of July 22, it was running at about 1,800 a day on a 7-day average, the administration says.

That’s also better than the 2,415 per day Mr. Trump was seeing in his final week in office in January 2021.

But Mr. Arthur said the Border Patrol arrests are only part of the border equation, and Mr. Biden’s numbers don’t account for the tens of thousands of unauthorized migrants who are streaming in each month through official border crossings and being caught and released under legally iffy “parole” programs created by the Biden team.

One of those parole programs allows 1,450 migrants a day to show up and gain entry at the southern border as long as they make an appointment for their arrival. If those are added to the 1,800 Border Patrol arrests, the southern border crossings leap to more than 3,200 a day, or well above the level at the end of the Trump administration.

Another parole program allows roughly 1,000 migrants a day from Cuba, Haiti, Nicaragua and Venezuela to bypass the border altogether and fly into airports.

All told, Customs and Border Protection encountered 205,000 unauthorized migrants in June, or more than double the rate when Mr. Trump left office.

The Congressional Budget Office this week estimated that the Biden border surge will add 8.7 million new people to the U.S. population through 2026, which is when the agency sees the chaos dissipating.

• Stephen Dinan can be reached at sdinan@washingtontimes.com.