Battling to stay on the presidential ballot in New York, Robert F. Kennedy Jr. on Wednesday testified for a second day in a Democratic-backed lawsuit challenging his residency, insisting that “I’m a New Yorker,” despite having lived on the West Coast for the past decade.

Mr. Kennedy, who is running as an independent, appeared in his own defense in the challenge from four voters who say he used a false address in Katonah, N.Y., on nominating petitions to get on the ballot. The challenge being heard in Albany argues that the Katonah residence is not his, but that of a friend, and thus the signatures on Mr. Kennedy’s petitions are invalid.

While Mr. Kennedy is unlikely to win an electoral victory in New York — or any state, if polls hold true — a decision to knock him off the ballot would be likely to lead to lawsuits in other states where his campaign used the same address to gather signatures.

Such a decision could have profound effects on the November election — Mr. Kennedy is seen as a threat to the candidates from both major parties in a close race. But testimony on Wednesday sometimes veered into the surreal, with questions about training protocols for wild birds.

In order to show Mr. Kennedy’s connection to California, where he has a home with his wife, the actress Cheryl Hines, a lawyer for the voters asked about his fondness for ravens. Mr. Kennedy said he liked to train them to eat out of his hand and perform tricks like putting poker chips in people’s pockets.

“Mr. Kennedy, how long would it take you to teach a raven to talk?” asked the lawyer, Keith M. Corbett, apparently seeking to show that the candidate spent a lot of time on such activities at his home in Los Angeles.