WASHINGTON (Reuters) - The rush of Central American children entering the United States illegally has eased from last year's crisis levels but remains brisk, according to new government data, and immigration experts fear the onset of warm weather could bring another surge.
More than 68,000 children traveling without parents, mainly from Honduras, Guatemala and El Salvador, were detained last year for entering the United States without immigration documents.
But there was a 42 percent drop in those arrivals in the five months ended on Feb. 28 from a year earlier, according to U.S. Customs and Border Protection.
"The situation has improved significantly," said Department of Homeland Security spokeswoman Marsha Catran. She did not speculate on what could lie ahead.
Law enforcement at the border now faces the start of the season that has produced the biggest surge in children fleeing Central American drug and gang violence in recent years.
Arrivals of undocumented children under age 18 spiked last March through June, causing the Obama administration to scramble to care for them and staunch the flow.
Even with the recently reduced flow, child migration is still on pace to match or exceed 25,000 for the year ending on Sept. 30. Fewer than 10,000 had been the annual norm until a few years ago.
Federal agencies are hoping to be better prepared if things get out of hand later this year.
The Department of Health and Human Services, which cares for unaccompanied children as they go through deportation proceedings, asked Congress for a record $967 million in funding for the year starting on Oct. 1, up from $149 million in 2011.
The agency also wants permission to create a contingency fund, stocked with an additional $400 million, in case U.S. efforts to discourage the children from making the dangerous journey fall short.
"We are all thankful the numbers are down," said Wendy Young, president of the advocacy group Kids In Need of Defense. She noted the conditions that contributed to last year's crisis - the desire to escape rampant drug and gang violence, domestic abuse and poverty - still exist.
Traveling without relatives and often escorted by smugglers, the children created a humanitarian crisis on the border with Mexico and a political challenge for President Barack Obama last summer.
Obama sent more security resources to South Texas, clamped down on smugglers and unleashed an information campaign discouraging youths from traveling to the border.
The surge in child arrivals strained an already burdened immigration court system while complicating the debate in Congress for major changes to antiquated U.S. immigration laws.
Republicans insist American borders must be secured before taking bigger steps.
The problem goes beyond children traveling alone, as illegal entries by families, meaning a child with at least one relative or legal guardian, also spiked last year.
So far, such entries at the southwest border were down 21 percent at 11,133 for the first five months of the fiscal year, according to government data.
Editing by John Whitesides and Lisa Von Ahn