After becoming the first group to legally challenge President Donald Trump's proposed U.S.-Mexico border wall, the Center for Biological Diversity sued the Trump administration Thursday for repealing protections for wolves, bears and other predatory animals that live on Alaska’s national preserves. By filing the lawsuit, the group challenged the constitutionality of the Congressional Review Act, which the Republican-controlled Congress used in February to dismantle a rule made by the administration of the former President Barack Obama.

The rule limited the hunting of animals such as wolves, bears and other wildlife in Alaska’s national wildlife refuges.

Read: First Lawsuit Filed Against Trump's Mexico Border Wall

Trump is not new to litigations because when he was a businessman he has had as many as 3,500 legal actions in federal and state courts during the past three decades against him. And after he took office, he had been named in more than 50 lawsuits in just over two weeks, according to reports.

In January, the city of San Francisco, became the first city in the U.S. to file a lawsuit over Trump's executive order targeting sanctuary cities. They claimed that Trump’s executive order restricting federal funding to so-called sanctuary cities for undocumented immigrants is unconstitutional, according to CNN.

Following the travel ban executive order of Trump, the American Civil Liberties Union (ACLU) has filed multiple lawsuits around the country with different plaintiffs who were affected by the travel ban, reports said.

The Council on American-Islamic Relations announced January it has filed a lawsuit challenging Trump's executive order on refugees. They claimed the travel ban is unconstitutional on First Amendment grounds because it creates "favored and disfavored groups based on their faith."

In January, Citizens for Responsibility and Ethics in Washington filed a lawsuit against Trump for violating the Constitution by illegally receiving payments from foreign governments. The foreign emoluments clause of the Constitution prohibits Trump from receiving any financial support from foreign governments, including foreign government-owned businesses, without the approval of Congress.