Plover Appreciation Day: 16 September
With just a handful of exceptions, shorebirds nest on the ground, constructing very simple nests. As a consequence, their eggs and young are particularly vulnerable to predation. Plovers and related species have evolved to minimize this threat by nesting in the open, allowing them to detect predators at a greater distance, and by having highly cryptic eggs and chicks. Early detection of predators allows the incubating adult to surreptitiously leave the nest and rely on the eggs and chicks being camouflaged by the surrounding substrate or vegetation.
Unfortunately, the very success of the strategy of highly camouflaged nests in open areas and cryptic behaviours means that humans can have major impacts on the survival of eggs and chicks without even knowing it! For many plover species this is confounded by the fact that their preferred habitats are some of the most popular for human recreation, such as beaches, shores of lakes and wetlands, and open grasslands. Many plover species are threatened by the direct and indirect impacts of people in their nesting habitats.
Within the Americas, there are 20 regularly occurring species in the plover family, Charadriidae. These include some of the most threatened shorebird species and populations in the Western Hemisphere. Four species are considered Near Threatened at a global level: Piping Plover (Charadrius melodus), Snowy Plover (C. nivosus), Mountain Plover (C. montanus) and Diademed Sandpiper-Plover (Phegornis mitchellii). At a regional level, both Piping Plover and the US Pacific Coast population of Snowy Plover are listed under the US Endangered Species Act, while the US Interior-Gulf coast population of Snowy Plover, plus Mountain Plover and Wilson’s Plover (Charadrius wilsonia) are all considered as “Greatest Concern” in the most recent assessment of the status of shorebirds in the US.
Diademed Sandpiper-Plover and nest. Photos: Diego Luna Quevedo.
The populations of several plover species feature among the least numerous of any shorebird (or bird) species in the Americas. The Caribbean tenuirostris subspecies of Snowy Plover numbers just a few hundred birds, while the entire global population of Diademed Sandpiper-Plover is believed to be less than 10,000 birds. The latter species is restricted to high elevation waterlogged mossy tundra and bogs (bofedales) in the southern Andes. Its English name reflects its striking plumage, and the ongoing uncertainty as to whether it is a sandpiper or a plover! Although not strictly a plover, the rarest shorebird species in the Americas is the Magellanic Plover (Pluvianellus socialis).The total global population of this species of Patagonian lakes and bays may be less than 1500 individuals.
Wilson’s Plover chicks in the Georgia Barrier Islands WHSRN Landscape. Photos: Abby Sterling.
The key to the survival of many of these imperilled plover species is co-existence between people and the birds, in particular at their nesting sites. To help build awareness and understanding about the need to share space with plovers, the 16 September is “Plover Appreciation Day” – aimed at raising awareness of the plight of ground-nesting plovers around the world! While you may have missed the chance to share some love with plovers this 16 September, please mark it in your calendars for next year!
