'We Have Nothing': What's Happening at the Southern Border as More and More Migrants Turn to the U.S.

Julio Cortez/AP/Shutterstock Migrants are seen in custody at a U.S. Customs and Border Protection processing area under the Anzalduas International Bridge, in Mission, Texas

There are thousands of stories like that of Hermelindo Ak, a father from Guatemala who worked growing corn and who had hoped, somehow, to be let into the U.S. with his teenage son after trekking north for more than 1,000 miles.

Instead the pair were almost immediately expelled to Mexico.

So Ak sent the 17-year-old on by himself and planned to return to Guatemala. As an unaccompanied minor, the boy would be received differently by American officials once he crossed the border. His father planned for him to stay with other relatives.

"I didn't want to leave him alone," Ak told the Associated Press. "Necessity obligates us."

There are thousands of stories like this at the border between U.S. and Mexico — and more every day.

In recent months the U.S. government has been grappling with a drastic increase in the number of unaccompanied migrant children crossing the southern border. March broke a record: 18,663 kids, traveling without family, encountered by border officials.

In total last month, agents encountered 168,195 migrants at the southern border — the most since 2001, according to the AP — which eclipsed previous highs in 2019 and 2014, during the Trump and Obama administrations.

That number of people, which is the result of many simultaneous factors including violence and economic pressures, has overwhelmed a system immigration advocates said was already ill-equipped.

And immigration has again been thrust into the national spotlight.

Here's what you need to know about what is happening.

RELATED: Biden Administration Asks FEMA to Help with Increase of Migrant Children at the Southern Border

Getty President Joe Biden

'There Are Not That Many Options'

While Republicans criticize President Joe Biden for reversing some of his predecessor's most hardline policies (GOP leader Kevin McCarthy called it "a human heartbreak" that was "created by the presidential policies of this new administration"), advocates decry what they describe as an unwieldy and often inhumane system that has left thousands of migrant children in jail-like facilities too much like their conditions under Donald Trump.

This is not the first time the federal government has been overwhelmed — what Biden's critics are calling a crisis.

Many migrants travel north every year seeking entry to America. But lawmakers have long been deeply divided on how to treat them or whom to allow in at all.

The Biden White House argues they are doing their best, that it takes time and that there are few — if any — universally satisfying solutions. They say they will not treat these people as the Trump administration did.

Biden officials also note that, under COVID-19 precautionary powers, almost all migrants are still being immediately expelled after crossing the border.

Children, however, are an exception — a reversal under Biden, who campaigned with a more compassionate message on immigration. More and more, because of changes in Mexico, migrant families are also being allowed to stay while their cases are processed, as are those people with what officials call "acute vulnerabilities."

But the government is also urging people to stay away.

Biden, 78, gave migrants a direct message during an interview with ABC News last month, "I can say quite clearly: Don't come."

"We're in the process of getting set up," the president said. "Don't leave your town or city or community."

"We recognize this is a big problem," White House Press Secretary Jen Psaki told reporters in March, placing blame with the Trump administration for a "dismantled and unworkable system."

Addressing the conditions of the migrant children, which have drawn the most scrutiny, Psaki said then: "It's not acceptable. But I think the challenge here is that there are only — there are not that many options. ... We have a lot of critics, but many of them are not putting forward a lot of solutions."

A spokesperson for Customs and Border Protection did not respond to PEOPLE's request for comment for this article.

CBP Two young Ecuadorian migrants speaking with a Customs and Border Protection official

JAIME RODRIGUEZ SR HANDOUT/EPA-EFE/Shutterstock A U.S. border facility in Donna, Texas

What's Causing the Increase in Migration?

Experts believe a combination of factors are leading to the spike in migrants at the southern border.

According to the AP, the majority of the people at the southern border are single Mexican adults. But Honduran and Guatemalan people are also arriving in substantial numbers, and the majority of them are either families or unaccompanied minors.

These people leave their homes for the U.S. because of violence and instability or for better economic prospects or as a result of devastating weather, including two Category 4 hurricanes in Central America in November.

Those storms displaced many families, crushing Central America's agricultural industry, which employs a majority of workers in Northern Triangle countries like Honduras.

Shelter, food and work have been in short supply for many in the region, according to a CBS News report last month.

"There is no employment, there is nothing," one father of three traveling from Honduras to the U.S. told CBS News. "We have to go out and find what we can offer our children, because we have nothing."

"These children are fleeing situations of extraordinary danger and violence, otherwise they wouldn't be making the journey," Jennifer Nagda, policy director at The Young Center, an advocacy group for immigrant children, previously told PEOPLE.

Jennfer Podkul, the vice president of policy and advocacy at Kids in Need of Defense, agreed. She told PEOPLE, "That's a common trend we see among refugee populations globally: When someone has to flee, they go to a place where they know they'll have support."

The Biden White House has been working with Mexico and Central American countries, reflecting the view that addressing these problems is not the work of one country alone and that it isn't expedient.

"They know it is something that can't happen overnight," the departing U.S. border coordinator, Roberta Jacobson, told The New York Times last week.

Homeland Security Secretary Alejandro Mayorkas said in March the Biden administration planned to invest $4 billion into Central America's Northern Triangle countries of El Salvador, Guatemala and Honduras in an effort to "address the root causes of migration."

There is another dynamic at work, according to the AP and other outlets.

President Biden, who campaigned in part on reversing the much-criticized "zero tolerance" approach to immigration under Trump, is being seen as much more welcoming though many restrictions are still in place. Nonetheless, many migrants traveling north are surrounded by disinformation and rumors about America's policies — fueling a false sense of hope.

Biden's administration did, however, stop sending unaccompanied minors back across the border in an effort to reverse what it says were Trump's "inhumane" and "ineffective" policies, which expelled all migrants — including children — during the pandemic.

Soon after taking office, Biden also reversed President Trump's "Remain in Mexico" policy, which mandated many migrants wait near the border while their cases were processed.

Biden began signing executive orders to reverse Trump's immigration policies hours after he took the oath of office in January.

"I'm not making new law, I'm eliminating bad policy," he said, before signing more orders in early February, which included ending the Trump-era policy of sending unaccompanied children back across the border amid the pandemic.

"Obviously we're going to have more kids in the country since we have been letting unaccompanied minors stay," Psaki said in March. "The last administration immorally kicked them out, in our view."

RELATED: Biden Administration Says Reopening Migrant Children Border Facility Was a 'Difficult Decision'

AP/Shutterstock A U.S. border facility in Donna, Texas

The Problem Is Space and Resources

With more children to accommodate, the government has needed more space and, in the meantime, has been squeezing thousands of people into a space designed, amid the pandemic, for much smaller numbers. That raised coronavirus infection concerns as well.

The Biden administration drew further ire by initially refusing to allow the media and lawyers physical access to such facilities, which themselves are controversial among advocates.

"This is not okay," Rep. Alexandria Ocasio-Cortez, a leading progressive, said after a Carrizo Springs, Texas migrant facility was reopened.

Some lawyers monitoring the situation reported children in custody having to wait days to shower and being in cramped quarters without access to the outdoors or use of a phone to contact others, according to the AP.

Two lawyers able to speak with more than a dozen children shared what they learned with ABC and CBS News in March.

"One of them shared that he could only see the sun when he showered, because you can see the sun through the window," Neha Desai, a lawyer at the National Center for Youth Law, told CBS.

Leecia Welch, a senior director of child welfare with the organization, told ABC that some children were forced to sleep on the floor while others experienced multiple days in a row without seeing the sun or going outside.

"What we saw this time was a lot of very young, very scared children," Welch said, adding, "These are places that no child should have to be in on their own."

The government now is racing to expand available facilities, though some of the sites were not licensed by their states, the AP reported.

"It's really a capacity question now," Yael Schacher, a senior U.S. advocate at Refugees International, tells PEOPLE.

Secretary Mayorkas also said in a statement in mid-March that it was an issue of capacity: "The situation at the southwest border is difficult" but "we are tackling it."

Migrant children aren't supposed to be held longer than 72 hours by border officials before they're then transferred to more appropriate facilities run by the Office of Refugee Resettlement, an agency within the Department of Health and Human Services.

Once in ORR custody, the children wait to be matched up with a U.S.-based sponsor such as their own family.

However, CBS News reported in March that about 3,000 of roughly 4,200 children being held at CBP facilities had stayed past that 72-hour limit.

Of the many migrants whom the government does expel — rather than attempt to prosecute them, as authorities did under Trump — some of them immediately attempt to cross the border again.

"What we're seeing now is people basically are being so rapidly expelled, they're trying again and again to come in," Schacher says.

Jaime Rodriguez Sr/U.S. Customs and Border Protection/UPI/Shutterstock A U.S. border facility in Donna, Texas

What's Next

Biden dispatched FEMA, the country's emergency response agency, to help handle the influx of migrant children.

In March, FEMA directed the Kay Bailey Hutchison Convention Center in downtown Dallas be used to house up to 3,000 boys from ages 15 to17. That decision, first reported by the AP, came as the government began converting an old oil field in Midland, Texas, into a temporary facility, as well as using military bases in California and Virginia.

The Biden administration has offered an "encouraging" commitment to immigration reform, Schacher tells PEOPLE, but "there are a lot of challenges" when it comes to implementing change.

"There's so many policies the Trump administration put in place to impede refugee protection in the United States, whether it's refugee asylum or refugee resettlement," Schacher says. "It is going to take time."

RELATED: Biden Administration Says It Will Allow Migrant Families Separated Under Donald Trump to Reunite in the U.S.

New legislation recently passed the House of Representatives but faces a far more uncertain fate in the Senate, given the Republican push for border restrictions rather than reforms.

"Kids should not be in large centers," Schacher tells PEOPLE, pointing out that the CBP facilities thousands of children are being held at were "notorious" and "extremely problematic under the Trump administration."

Podkul, another advocate, said that while her organization was grateful the Biden administration was "taking child protection seriously," she wanted the government to envision. its approach to migrants differently.

"[The country] really needs to create a system that isn't just based on a law enforcement approach to these kids and make sure we are receiving them in a humanitarian way — so they aren't dropped over a wall or abandoned in a desert," she said.

• With reporting by VIRGINIA CHAMLEE