I’ve noticed a change on Assawa Lake, the shallow lake behind my home that I’ve mentioned many times over the years. Classified as a Natural Environment Lake by the state of Minnesota, the peaceful little lake, known locally as Mickalson’s Slough, with no inlet or outlet, has provided me with plenty of writing material over the past 19 years that I’ve been blessed to live beside.
Natural environment lakes are unique bodies of water. Defined as lakes usually “. . . less than 150 total acres, less than 60 acres per mile of shoreline, and less than three dwellings per mile of shoreline . . .”, these lakes are generally subject to winter kill, have swampy shorelines, and are less than 15 feet deep. Moreover, county governments have further protected these important basins by having in place shoreland ordinances that enact specific setback requirements, very limited development, and restrictive rules against clearing vegetation—any vegetation—on or near the shore and adjacent uplands, not to mention within the water itself.
The qualities of Assawa Lake are numerous. Replete with emergent native aquatic plants such as white water-lily, yellow pond-lily, and watershield, the lake also includes an abundance of other plants important to waterfowl for food such as sago pondweed, smartweed, native milfoil, bladderwort, duckweed, arrowhead, water plantain, and many species of rushes and sedges, to name just some. A narrow band of cattails surround the basin along with wet and sedge meadow areas, back bays, and forested and brushy uplands.
So what’s the change I’ve noticed? Birds. Fewer of them and fewer species that I once observed.
This is hard to come to terms with, really. Species that were once commonplace are no longer showing up to breed and nest. Species that I formerly observed and delighted in listening to are either dramatically diminished in numbers or are absent altogether.
During spring seasons many years ago (not so in the past several spring and summer seasons), Assawa Lake was alive with the activities of vocalizing and chasing territorial male red-winged blackbirds and nesting females. Although there are still a few nesting pairs, including this spring, red-winged blackbird activity is nowhere near what I once observed.
The possible reason? According to research conducted on the species, climate change and habitat loss are the driving forces responsible for most of the global population declines in songbirds and other birds, including red-winged blackbirds.
Cornell Lab of Ornithology reports that red-winged blackbird populations have, “. . . declined by over 30% throughout most of their range between 1966 and 2014, according to the North American Breeding Bird Survey.” Another organization, Partners in Flight, estimated the global breeding population of about 130 million, which is down from 190 million in 1974.
While a population of roughly 130 million red-winged blackbirds is still considered abundant, I have noticed, although admittedly on a very small scale, that the local red-winged blackbird population has declined by at least 30% if not by more than even this. Whereas habitat conditions haven’t necessarily changed all that much, if at all, on Assawa Lake in any major way that I can discern, the cattail beds that were previously teeming with red-winged blackbirds are largely vacant nowadays.
Other birds, too, have become noticeably absent or less plentiful on Assawa Lake in recent years. Those species include American bittern, great blue heron, green heron, common yellowthroat, common snipe, and sedge wren. And some species seem to be holding their own or have increased slightly such as ring-necked duck, hooded merganser, Canada goose, trumpeter swan, sandhill crane, and song sparrow.
It’s alarming when familiar and bountiful birds are less numerous than they once were. Oft said that we only notice something when it’s missing is especially true with ubiquitous small little birds that are no longer everywhere as we get out and enjoy the great outdoors.
Blane enjoys getting feedback from readers and hearing about your stories from Minnesota’s great outdoors. Email him at email@example.com.