The Spotted Sandpiper is not your ordinary bird. We were fortunate to have a pair nest at Clark St Beach Bird Sanctuary (CSBBS) this summer. Though seen often, the birds’ nesting behavior is unlike the Piping Plovers that nested in plain view at Montrose. Spotted Sandpipers keep their nests to themselves.
Spotted sandpiper breeding territory needs a shoreline, a partly open area for their ground nest, and dense vegetation where chicks can be protected.
The CSBBS area just south of the beach house, where a dense stand of marram grass (beach grass) anchors a dune, fulfills its requirements. Sightings of the sandpipers on ebird, the database for recording citizen science data on bird observations, confirmed the birds were there from May 5 through July 17.
Suzanne Checchia, who is in charge of bird monitoring at CSBBS, was asked in July if it would be okay for CSBBS volunteers to begin work in the area. She noted she had seen a Spotted Sandpiper acting possessive and asked for time to discover its nest. This would be a challenge, as the nest is just a slight depression scraped from the soil and lined with grasses, and the chicks are hidden deep in a grassy area.
Ms. Checchia wrote in an article for Evanston North Shore Bird Club’s newsletter “Bird Calls,” from her first sighting on July 5, “the birds were often seen walking along the top of the breakwater, foraging in the large ‘fluddle’ on the beach, occasionally flying into and out of the vegetated area. [A fluddle is a temporary medium-sized area of water, somewhat between the size of a flood and a puddle.]
“What were they doing if not nesting? On several occasions during the season, I walked (slowly and carefully) through the vegetation when the adults were present on the beach. I found no evidence of a nest, nor did the adults pay me any mind.
“When I arrived at the beach on July 17, with little hope I decided to walk eastward along the breakwater toward the lake. About halfway along the barrier, an adult spotty landed on the barrier to the west of me, vocalizing persistently. As I continued walking eastward, ahead of me on the sand was a good-sized juvenile looking pretty comical with lots of fluffy feathers hanging off its body.
“Another adult appeared, peeping loudly, and the juvenile disappeared into the vegetation. Mission accomplished.”
Yet, where was that nest?
This small shorebird is easily identifiable by its unique walk and flight. Its entire body bobs continuously as it probes the sand for food. As a carnivore, some dietary items are flies, grasshoppers, crickets, beetles, fish and spiders. The tiny seashells along our beach provide calcium to females. Its flight is also distinctive. Most shorebird species have deep wingbeats.
The spotty has a “stuttering” flight – short wingbeats alternating with glides. The sexes look alike. In summertime, the bird lives up to its name and has a spotted breast, but in winter, when I’ve seen it while vacationing at Sanibel Island, its breast is pure white.
Spotted Sandpiper breeding behavior is anything but typical. The female literally rules the roost. She usually arrives at her summer area before the male, selects the nesting territory and initiates courting.
She may perform an aerial display to attract potential mates up and down a shoreline, with a swooping flight and wings held open. Or she may display from the ground, puffing up her chest and strutting.
She chooses her mate. In fact, she may (or may not) have several mates and several nests simultaneously. She may or may not help incubate the eggs. Once there are chicks, watching over them becomes the male’s job.
Chicks are precocial: They can walk away from the nest within a few hours of hatching, and can feed themselves. But they still need adult protection.
According to Cornell Birds of America Online, “males tend to have more of the pituitary hormone prolactin than females. Prolactin promotes parental care, which may explain how the role reversal develops each season.”
She belligerently defends her territory and her mate from others who might have an eye on him. This breeding system has a name: polyandry. (Note the continual use of the word “may”; Spotted Sandpiper behavior seems very variable.)
This is a species that bears watching, though from a respectful distance so as not to disturb nesting. Spotted Sandpipers tend to return to a successful nesting territory, so let us hope we see them again next summer.