Notes on the construction destruction at Garland Park Lake

So, you might wonder what the rant at the beginning of this set of observations was all about. After all, there were plenty of Bluets, some Skimmers, and a couple of Meadowhawks around, as well as a few birds and a butterfly. Let me tell you, then, what was missing from the picture.

While there were plenty of Familiar Bluets around, there were no Tules or Oranges that I could find. No Spreadwings or Dancers at all. One lonely Forktail. Plus, the majority of Zygoptera that I saw were male.

In the category of Anisoptera, Darners were missing altogether. No Pondhawks. No Black Saddlebags. Only one species of Meadowhawk, and an overall male-to-female ratio even worse than that of the damsels. I'm also accustomed to seeing multiple species of Lepidoptera at this location. This time, there was the single Skipper—not that there was a whole lot in the way of nectar options. The lakeshore used to be rich with milkweed, native asters, and other flowering plants; they had all been bulldozed.

Avian species were similarly absent. Previous visits have turned up finches, blackbirds, swallows, and even the occasional warbler. At this visit, there might have been a couple of House Sparrows, but if there were, I couldn't hear them over the heavy equipment. Among water and shorebirds, the egret and cormorants were the first species other than geese that I had seen all spring and summer.

Historically, this little lake has also hosted a decent population of Virile Crayfish (Faxonius virilis). I've posted observations of the species from this location, and I wasn't even looking for them. This time, though—not a sign. My suspicion is that, while some of the population made it over to Cherry Creek, most were killed during the denuding of the lakeshore. Among the longer-term repercussions is that anyone hoping to see Mergansers at the lake is going to be disappointed for at least this winter.

This is an urban park, and I understand that there is a balance to be struck between the needs of the people living in the area and the needs of the wildlife that gets displaced. The reason for all of the destruction and construction is a stormwater diversion project, with new outfalls to both Lollipop Lake and Cherry Creek. I also know that the lake (and now you understand why I rarely use its actual name) has long been viewed dismissively by Denver.gov as "[offering] little diversity in aquatic habitat", while admitting that at least parts of the lakeshore are attractive to wading birds. The concept art for the new outfall has at least the potential to create some habitat variation by way of a wetlands, but it also calls for "ornamental trees" along the drainage corridor. The heavy construction is finished, and the razed areas are being replanted: "native seeding" (whatever that means), sod (possibly the Bluegrass that caused previous water quality issues), shrubs, and trees. Nowhere in the project documents does it say what species are being used for restoration, aside from a vague reference to "native upland grasses" along the outfall channel. Furthermore, my suspicion is that the view of Garland Park's lake as having little habitat diversity led to an assumption that there was a similar lack of species diversity. It does not appear that any kind of wildlife or plant survey was done in advance of the project, nor have I been able to get an answer from the project manager about any such preliminary steps.

All that I can say for certain, as of this moment, is that the drop in species diversity at this location is concerning. At some point, the changes and additions to the landscape might make this an even better location for urban naturalists of all stripes. That point, however, could be years in the future. What has been lost was a sadly undervalued reservoir of habitat.

Julkaistu marraskuu 9, 2023 09:01 IP. käyttäjältä gothhobbit