I'd meant to read the MYSTERIES IN OUR NATIONAL PARKS series in order, but after getting back from visiting a couple of really awesome national parks (Arches & Canyonlands), I'd figured I'd just read them as they became available by my local library. So #4 in the series, DEADLY WATERS, came in first, and this is another mysterious-and-surprisingly-dangerous adventure for the Landon kids in Everglades National Park in Florida.
My parents are now permanent residents in Florida, though north of Tampa (actually, near Crystal River, which gets a mention in this book -- this is an area where manatees like to stay in the winter). It would be a hike to get down to the Everglades, and I wouldn't want to attempt it in the summer like the Landon family does in the book -- while they do mention all of the mosquitoes, I guess they fail to note the concerns for those who are actually allergic to mosquito bites (like me!) or even the more serious diseases you can get from mosquitoes, like West Nile, EEE, etc. But it does sound beautiful, especially if you have a friend down there with a boat and who knows the waterways really well. The diverse wildlife is mentioned frequently in the book.
The mystery this time is figuring out why there are a number of puzzling but rising manatee deaths. The Landon kids (Jack & Ashley) and their current foster charge, a rather male-chauvinistic kid named Bridger (he grew up without a mom and his father, a touring rodeo champion, is currently stuck in the hospital undergoing rehab after a major injury), come across a villainous, shady guy who steals Jack's camera (to destroy any evidence) and later pulls a gun on them. No one gets hurt, even later in the book when the entire Landon family get involved in a boat chase and the bad guy's boat overturns in the water. This family has some relatively scary life experiences! Despite that, everything turns out as good as can be expected: Bridger learns a lesson in feminism, they figure out what's poisoning the manatees (though solving the issue will be much longer and probably result in some deaths, when it could have been prevented in the first place), Jack gets his camera back, bad guy goes to jail. What more could you want in a children's mystery series?