Ecology and Threats
What are Piping Plovers and Where do They Live?
The Piping Plover is a sparrow-sized shorebird that relies on its cryptically coloured feathers to secretly nest and evade predators on coastal beaches. In spring and summer, Piping Plovers are found on sand and pebble beaches from Newfoundland to South Carolina. Adult plovers return to Nova Scotia to breed in late April and May. From May to August, plovers lay their eggs on the open sand between the grassy dunes and the high-tide mark (see illustration below). In fall and winter, plovers are found along the coast of southeastern USA and the Caribbean Islands. Read more on Piping Plover life cycles and habitat.
In Nova Scotia, Piping Plovers breed on less than 30 beaches in southern NS (Shelburne to Halifax Co.), Northumberland Shore (Pictou and Antigonish Co.), and in Cape Breton (Victoria, Inverness and Cape Breton Co.). Many traditional breeding beaches have been lost due to natural and human-induced changes.
Figure 1. Piping Plover nesting areas Atlantic Canada. Map from Environment Canada.
About two-thirds of Nova Scotia's Piping Plovers breed in southern Nova Scotia. This small southern group appears to be reproductively isolated from the rest of the eastern population. Thus a bird hatched in southern Nova Scotia will likely return there to breed, and it is unlikely that birds hatched elsewhere will breed in southern Nova Scotia. This subpopulation's small size, isolation, and its poor reproductive success put it at risk of continued decline and possible extirpation (extinction from the region).
What is the Status of Piping Plovers?
Populations declines: There are less than 40 breeding pairs in Nova Scotia - a decline of over 25% since 1991 (see Figure 2 below). In southern Nova Scotia, numbers of breeding pairs and breeding sites have declined by nearly 50% since 1991.
Figure 2. Estimated number of breeding Piping Plover pairs in Nova Scotia (International Piping Plover Breeding Censuses
in 1991, 1996, 2001 and 2006 (the latest census), Canadian Wildlife Service, unpublished data).
Reproductive Success - Good News & Bad News: Reproductive success can be measured by how many fledglings are produced per pair. Piping Plovers in northern NS tend to produce more than 2 fledglings per pair, which is above the 1.65 chicks/pair needed to maintain the population at its current level. In southern NS, not nearly enough chicks are produced to sustain this reproductively isolated population (see Figure 3 below).
Figure 3. Annual productivity of monitored breeding Piping Plovers in Northern
and Southern Nova Scotia between 2001-2006 (Canadian Wildlife Service, unpublished data).
Why are Atlantic Piping Plovers endangered?
Loss of breeding beaches due to natural and human causes.
Human activities on beaches (vehicle traffic, development of houses/other structures on dunes) can damage breeding habitat.
Predators of plover adults, chicks and eggs, including American Crows, Common Ravens, fox, mink and roaming dogs and cats.
People approaching too-close to breeding Piping Plovers can lead to nest detection by predators, abandonment of eggs, death of chicks, and abandonment of beach as a traditional breeding site.
High tides or high winds can flood nests or threaten chick survival.
What Laws Protect Piping Plovers and Their Habitat?
- Species at Risk Act (federal)
- Migratory Bird Convention Act (federal)
- Nova Scotia Endangered Species Act
- Nova Scotia Wildlife Act
- Nova Scotia Beaches Act