When Jeff Pert sits down to pen a cartoon, he isn't thinking about how many T-shirts it will sell. He isn't even thinking about what the thought bubble over the lobster will say at first; for the Maine-based cartoonist, the ideas come naturally.

“The only bad day I have is when I can't come up with anything,” he said. “Other than that, it's really hard to have a bad day doing this.”

On Saturday, Feb. 16, Pert spoke during a Literary Lunch at the Boothbay Region Memorial Library where he detailed his start in cartoons to the release of his book, “Cartoons From Maine.”

Pert's career in drawing started at an early age; instead of paying attention in school he would doodle in his notebook and devour the comics in the Boothbay Register, where his father was the editor in the early 1960s.

Fresh out of college Pert was hired to be a political cartoonist for the Times-Record in Brunswick for a short period.

While his dreams of penning a syndicated cartoon a la Charles Schultz weren't realized, he learned some invaluable lessons along the way.

“That was where I really cut my teeth,” he said. “I was working on a deadline, which caused me to come up with something new every week.”

Eventually, Pert's brother came up with the idea to brand merchandise with some cartoons that showcased a little bit of Maine life and culture. The next thing the pair knew the products took off and made Pert's signature drawing (a lobster asking his friend Bob how the water is), an instant hit.

His work was then featured in Down East magazine and on magnets, T-shirts and mugs from Fort Kent to Caribbean. With www.zazzle.com he said he has been able to spread his work out even more.

Pert said a lot of his cartoons are tweaked to reflect modern times, which presents unique challenges.

“A lot of it is 'What would a lobster say in a bar?' or 'What does a moose talk about on a cell phone?'” he said.

Sometimes, the best tweaks and additions come from fans of his work. His drawing entitled “Who Farted?” featured a lobster tank filled with lobsters and one asking the eponymous question.

“Originally, there were no bubbles coming out of the tank,” Pert said. “One guy asked me about it, and I thought about it and it made me laugh. So the fart bubbles were added.”

There is also a regional flare to his work. While moose sell in Maine that might not be the case out west. So, elk are substituted as the antler-ed creature of choice and most of the jokes stay the same.

In mid-Atlantic states like Maryland, and in the Pacific Northwest, the lobster is swapped out for a crab.

While the characters switch the humor stays the same, Pert said, adding that a crustacean wearing a shirt that says, “I'm with stupid” will work almost anywhere.

In addition to his book and his lobster drawings, Pert is also working on Dysfunctional Dogs, which features dogs doing what Pert describes as the activities that make their owners go nuts.

He is also drawing a comic strip called “Surf N Turf” that features Claude the Lobster and Kevin the Moose.

“I'm still figuring out their personalities,” he said. “It'll come to me.”

Ben Bulkeley can be reached at 207-633-4620 or bbulkeley@boothbayregister.com. Follow him on Twitter: @BBRegisterBen.