I've enjoyed using my family history hobby as a jumping off point for the family history mysteries, and my friend Karen Musser Nortman does a bang-up job with the Frannie Shoemaker Campground Mysteries. Since she camps all summer, she also has a built-in marketing modality -- never a bad thing.
I read several recreation or theme-based series. To get a better sense of how other authors handle hobbies in their books, I did a couple of Google searches, with limited success. Google kept wanting to guide me to articles about the best hobbies to list on a resume if you don't have a lot of job experience. Not helpful.
In the genre I write in most, cozy mysteries, there is an entire category for cozy craft and hobby mysteries. A quick survey shows food predominates, with authors such as Joanne Fluke, Ellery Adams, and Abigail Frost. I am a big fan of Molly MacRae's Haunted Yarn Shop Mysteries.
Pets may not be considered hobbies, but there are plenty of cat and dog mysteries. I like the Pampered Pet Mysteries by Sparkle Abbey, which is a good mix of pets and crime. I've read other pet-based mysteries (authors to remain nameless) that focus as much on the pet angle as the mystery. There's only so much I need to know about vet visits and animal costumes.
I think balance is the key for any theme-based book or series. Too much about cooking techniques, bakery shops, or genealogy searches and readers can be turned off. Maybe not if they are big-time into a pastime, but that could narrow the audience.
Until writing the Family History Mystery Series, I started with the setting. I love the Jersey shore, Iowa Rivers, and small towns. It hit me that if I merged a hobby through which I knew people it could lead to readers. Why didn't that occur to me ten years ago? No matter. What matters is I'm having a blast.
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