12 September, 2023
By Rick Passaro
Rick Passaro (standing, first on the left) with the 2023 Piping Plover banding team at Lake Superior, Wisconsin, USA. Photo by Sumner Matteson.
Migratory shorebirds that nest on North American beaches, Piping Plovers (Charadrius melodus) exhibited steep declines by 2001, when only 3000 pairs were documented, leading the US Fish and Wildlife Service (USFWS) to list their Atlantic coast populations as threatened and Great Lakes populations as endangered. Due to human activities and predators on beaches where they nest, their survival has become increasingly dependent on conservation actions such as fencing nesting areas, restricting vehicle use, and removing invasive predators. Having previously worked several nesting seasons with the Atlantic coast populations of Piping Plovers, I had long wanted to spend some time assisting with the management of any of the inland populations by way of comparison. I was interested to see just what differences there might be in overall program management, species behavior and in the birds themselves. The answer, I recently discovered was: a lot!
Banding Piping Plover chicks. Photo by Rick Passaro.
As the 2023 shorebird nesting season rolled around, I was excited to be fortunate enough to secure one of two Piping Plover Monitor positions being offered by the Natural Resources Department of the Bad River Band of Chippewa Indians (“the Tribe”) on Lake Superior in Wisconsin. While Piping Plover nesting beaches officially occur within the Apostle Islands National Lakeshore and therefore come under the purview of the National Park Service, these lands have traditionally been tribal lands and currently share a boundary with the reservation, so a cooperative agreement was established. To protect and restore endangered Piping Plovers in this area, the Tribe works in collaboration with the US National Park Service, Wisconsin Department of Natural Resources, USFWS, Detroit Zoo, and the University of Minnesota, among others.
Releasing Piping Plover chicks after banding. Video by Sumner Matteson.
The plover nesting areas are found on a long spit of land thrusting into Lake Superior, which delineates Chaquamegon Bay to the south. This is called Long Island by the National Park Service and Chaquamegon Point by the Tribe. Although this was the final “island” to be added to the Apostle Islands, it is currently not an island at all but a long peninsula – a state of affairs I was told could be altered at any moment by one of the many frequent storms of the capricious Lake Superior. Be that as it may, the only way to access Chaquamegon Point is by boat, as there are no roads or bridges. There, two Piping Plover monitors work out of a primitive tent camp consisting of a large walled sleeping tent and a screened “mess tent” complete with a bear box to discourage well, bears, from raiding our stores.
Mess tent for Piping Plover monitors. Photo by Rick Passaro.
All equipment and supplies had to be hauled in by boat including enough food and water for a four-day stretch – including some extra in case foul conditions prevented a timely swap-out. Each monitor worked four days on the job followed by four days off. During our days off, we were housed in the dormitory of a local community college. The fifth day was a “swap day” that saw one of us coming out of Plover Camp and the other going in as he or she watched the boat disappear either lakeside or bayside, depending on weather and wave conditions. Our first order of business was to find nests, set up predator “exclosures” as well as what is here called “psychological” string fencing but what we call on the coast “symbolic” fencing. Finding the first nests did not take long. Working as a team the first day, we found three nests that would turn out to be 50% of all nests for the season. Obviously, the birds had been back from their wintering grounds for some time as it takes several weeks for them to stake out territories, pair up, and begin laying.
Home Sweet Home. Photo by Rick Passaro.
One difference I noticed with Great Lakes plovers was that the males and females were much easier to distinguish than their coastal counterparts. Males have a much heavier and more complete brow and the black and orange coloration on their bill is much more delineated in males than females. And management? Holy cow! Very, very intensive! But let’s not forget, these populations are federally listed as endangered whereas the coastal population is listed as threatened. All chicks are banded so nearly every individual is identifiable – many even have names!
Adult Piping Plover. Photo courtesy of Wikimedia Commons.
We immediately installed exclosures around all nests to protect them from predators. An unfortunate incident illustrates why. In this case, when we were unable to immediately install an exclosure due to weather conditions, the eggs were depredated by gulls. While the plover pair remained in the area for most of the season, they never re-nested. This was frustrating, and brings me to another point of contrast. Re-nesting is practically a given with the Atlantic population. Due to storms, freak tidal flows or predation, coastal birds will sometimes re-nest two, three even four times! By contrast, with the Great Lakes population, it is cause for celebration if a pair re-nests. Re-nesting is not wholly out of the ordinary but not a given, either. This might have something to do with the relatively short nesting period in the Great Lakes compared to the Atlantic coast. In the Great Lakes, by the end of July, it was all over. All the eggs had hatched and all surviving chicks had officially fledged. By contrast, in the Atlantic population, the breeding season can easily stretch into late August and sometimes even early September.
Plover nesting beach on Chaquamegon Point. Photo by Rick Passaro.
Chaquamegon Point remains the most productive Piping Plover nesting ground for the entire state of Wisconsin. In 2023, we discovered and monitored a total of six Piping Plover nests. One was depredated by gulls, one was abandoned for unknown reasons, and four other nests were successful, meaning that all produced fledglings. Several chicks disappeared prior to fledging, presumably predated; there is no lack of suspects: gulls, merlin, northern harriers, coyotes, crows. The grand total of Piping Plover fledglings on our beach was nine. Now, this might not sound like a lot but when you consider that the entire Great Lakes population stood at an estimated 18 pairs in the early 1980’s, that’s a substantial contribution to the population in just one season. Moreover, all four eggs from the abandoned nest mentioned above were successfully hatched, and the chicks were raised at the University of Michigan's Biological Field Station, where the Detroit Zoo operates a captive rearing facility. These birds were then released into the wild in an exciting event that was the first release of captive-reared Piping Plovers in Wisconsin. Hopefully it won’t be the last!
Behind the dunes. Photo by Rick Passaro.