Most of the wetlands areas in Boulder County, and along the Front Range in general, are artificially created. Sombrero Marsh, a little-known park in Boulder, is one of the few remaining natural wetlands. I’ve seen it described as an “alkaline salt marsh,” which I guess must be a definition of “salt marsh” that doesn’t require it to be coastal, but it’s known as a great site for spotting more unusual migratory wetlands birds.
Back in June, during a ridiculous heat wave, I decided to stop by to visit a former coworker now working at the Thorne Nature Experience, an outdoor education organization which manages Sombrero Marsh along with the City of Boulder Open Space and Mountain Parks and the Boulder Valley School District. Sombrero Marsh is dry most of the year, filling with seasonal rain and snowmelt. In June I mostly noticed the heat–even at 6pm I didn’t want to stay out on the trails long. I did spot a few animals, including ducks, a Punctured Tiger Beetle (Cicindela punctulata), a Twelve-spotted Skimmer (Libellula pulchella), a skipper of some kind, and assorted damselflies.
After the stormy weather of the last few weeks, I expect it’s pretty wet right now, and things have cooled off a little, so I’ll have to go back again. The marsh is open daily during the week (directions), although I believe it may be closed on the weekends.