Piping Plovers migrate a long way each year to nest on the shores of the Great Lakes. Great Lakes Piping Plovers winter in the southern Atlantic and Gulf of Mexico coasts of Florida, Texas, Bahamas, and Mexico. They fly north between mid-April and mid-May to begin their nesting season. Adults often return to the same beach to nest.
Piping Plovers are habitat specialists — they have figured out a particular strategy and have specific requirements for nesting successfully in the spring. The best beaches are wide, sandy, and over one kilometre long.
Males will attract females by digging “scrapes” — small depressions in the sand that may be decorated with small shells or driftwood. The male Plover can be aggressive when defending his territory against other male Piping Plovers. The female Plover ultimately chooses the nest site, selecting one of the scrapes that was created by the male. She will lay up to four eggs over the course of a week. The eggs in the scrape are referred to as a “clutch of eggs.”
Because of the hard eggshell, most birds cannot lay their entire clutch of eggs all at once. They will lay one egg, and then have to wait twenty-four hours for the next egg to develop. In order for all the eggs to hatch at the same time, adults won’t incubate or sit on the nest until the last egg is laid.
After the final egg is laid, both the male and the female will take turns incubating the eggs. When the adult is relieved from its incubating duties by its partner, it spends time foraging or looking for food along the beach. Incubation shifts can be anywhere from thirty minutes to four hours!
The chicks will hatch in 26–30 days. Once hatched, chicks are immediately mobile and active. Some Plover families will stay close to their original nest site, while others may venture along the beach. However, they are still very small and are particularly vulnerable to predators. Parents remain vigilant to protect their young from predators including gulls, crows, Merlins, and domestic pets. Disturbing or distracting parent Plovers when the chicks are still young could allow a predator to have a successful hunt. Chicks are also vulnerable to the cold and rely heavily on their parents as a source of heat. Chicks will “brood” or huddle underneath one of their parents to stay warm. The parent may look like it has ten legs and be doubled in size.
Usually the mother Plover will start her migration south when the chicks are two to three weeks old, and the father will remain to guard and teach the young. The chicks grow to be the size of adults in three to four weeks. The father Plover will start his migration south when the chicks are four or five weeks old and have demonstrated an ability to fly. The chicks remain on the beach until they have eaten enough to fuel their flight south. They will continue to practice flying during this stage, and will use more areas of the beach. The young Plovers will fly to overwintering areas on their own.
It is still a mystery how they know where to go without following an adult Plover. We won’t necessarily see these young back on our beach, as juveniles will usually disperse to avoid nesting on the same beach as their parents. However, successful parents usually do return to the same beaches, and individuals are recognizable by the coloured bands placed on their legs. Most of the new or first year birds we see along Lake Huron’s shoreline were hatched from nests in Michigan, reinforcing that international cooperation and communication is essential for the survival of this species.