Tougher enforcement of immigration laws nationwide is being felt among members of the significant immigrant population on Martha’s Vineyard, most of whom are from Brazil. And while there have been no reports of recent raids here, news of crackdowns in other communities near and far has contributed to a heightened atmosphere of apprehension on the Island. More than once in recent months, reports have spread rapidly through the Vineyard Brazilian community that ICE agents are present on the Island. Few people are willing to talk about it publicly.

Immigration attorneys and others who work with immigrants on the Vineyard say they have not seen an increase in deportations, but they said the enforcement environment has become more unpredictable.

“Immigration is coming to the Island more than they used to. They have the resources to do it. They are enforcing orders, and there’s not necessarily any rhyme or reason to why one person seems to be a priority over somebody else,” said Rachel Self, an immigration attorney who lives at Cape Pogue and commutes to Boston.

“There are many, many cases where people who immigration would not have been interested in a couple years ago, nothing has changed in their situation, but now they’re interested in them,” Ms. Self added.

Sarang Sekhavat, federal policy director with the Massachusetts Immigrant and Refugee Advocacy Coalition, echoed the notion that ICE priorities are unclear. Mr. Sekhavat meets regularly with ICE leadership at their New England field office in Burlington.

“Without a doubt, under the previous [Obama] administration, [ICE] had their priorities for how to enforce the law,” Mr. Sekhavat said. “The local field office . . . was very good about exercising prosecutorial discretion any time they came across someone who didn’t fit into those priorities.”

He said despite changes in enforcement, he has not seen increased deportations.

Rachel Self is an immigration attorney who lives at Cape Pogue and commutes to Boston. — Ray Ewing

“We’re seeing this odd mix of more people getting into system, but the system seems to be more clogged up,” he said. “So even though more people are in the system, we’re getting much bigger backlogs at immigration courts. We’re not seeing the same number of deportations because the courts can’t keep up with it.”

Mr. Sekhavat estimated that the state has the capacity for 750 to 800 undocumented detainees, most of whom are detained at houses of correction in Suffolk County, Bristol County and Plymouth County.

Exact population numbers for the Island’s deeply rooted Brazilian community are not known, but there are indicators — including an increasing number of non-English-speaking students enrolled in Island schools — that suggest the Brazilian population is robust and growing. Many undocumented people living on the Island enter the country lawfully with a visa and then overstay their visa. Others cross the border.

Island immigrants have varying relationships with immigration enforcement. A federal program that dates to 2002 but came into more active use in 2014 requires many undocumented immigrants to be fitted with ankle devices that allow ICE to track their whereabouts. On the Island, many undocumented people are required to check in with ICE regularly at its office in Burlington.

The Burlington office oversees enforcement for undocumented people living in Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. The acting field office director is Marcos Charles.

Meanwhile, Mr. Sekhavat described a growing atmosphere of uncertainty. He said in addition to murky priorities, area ICE leaders appear to have less of a say now in how the law is enforced.

“What we’re seeing out of local field office is where we used to be able to work with them on individual cases and say, Hey, this person doesn’t fit into their priorities. Can you let them out? And they often would. Now they’re just saying, Yeah, sorry we can’t.”

In an email to the Gazette, John Mohan, a spokesman for ICE in New England, declined to specify how many times ICE has visited Martha’s Vineyard this year. He said when it comes to arrests, the agency does not work by town. Countering statements from others, he said the mission of the agency has remained largely the same.

“While I can’t say I necessarily recognize ‘changes’ in the way ICE carries out its mission, it is true that, since January 2017 ICE does not exempt classes or categories of removable aliens from potential enforcement,” Mr. Mohan wrote. “Any individual determined to be in violation of U.S. immigration laws may be subject to arrest, detention and removal from the United States.”

Cong. Bill Keating, who represents the Island in the ninth district, said constituents from the district routinely contact his office for immigration advice. Reacting to recent news reports and threats from President Trump that ICE would be conducting large-scale raids in major cities, Mr. Keating called for a more efficient system for people to obtain lawful status.

“When you have the president saying that this is what they’re going to do . . . it’s taken seriously,” he told the Gazette by phone. “People aren’t sure what he means, but the fear side of it the divisive side of it, the name-calling side of it . . . sadly that hasn’t stopped.”

Ms. Self said she urges people to seek out accurate information and know their rights. For example, ICE is not permitted to enter a home without a valid search warrant signed by a judge. The warrant must have the individual’s name and correct address. It is okay to ask an agent to slide paperwork under a door or hold it up to a window, she said. She advises people not to sign any documents without asking to see an attorney, and she cautions people to do whatever they can to avoid criminal charges.

She said the history of the Island Brazilian community, which dates back for more than three decades and has entered a second generation, is an important asset.

“The bottom line is the bulk of people who are here are not people who arrived last month. We have people who are really, really rooted in this community,” she said. “People are going to find the resources to fight and find the resources to stay.”