Traditional management techniques for piping plovers include closing areas of the beach with psychological/symbolic fencing and erecting predator exclosures around each nest. Since 1988, predator exclosures have been effectively used to increase hatching success (see bottom figure). Daily monitoring of each pair during the nesting season has permitted evaluation of these management strategies. They are supplemented with the following additional management techniques:
Captive rearing has been used as a last resort salvage effort in the event of nest abandonment since 1992. Through 2000, 29 captive chicks have been raised and released. One captive reared individual returned as an adult for 3 consecutive breeding seasons and successfully raised offspring. Fledging success is greater than 90% with captive rearing, as compared with 25-76% fledging success in the wild. This technique is an important option for population augmentation.
Temporary Artificial Incubation
Under various circumstances, we removed eggs from the nest, replaced the real eggs with fake eggs (Femo), and placed eggs in a Lyon Marsh incubator for up to several days. These actions were taken to avoid egg loss from predation, extreme weather, human disturbance, and/or temporary abandonment. In 7 of 8 cases, the real eggs were exchanged back into the nest and incubated by the pair to hatching; in the eighth case, a predator ate the fake eggs, resulting in nest abandonment.
Predation of nests is not predictable, and predation can occur prior to completion of a clutch when a full-sized predator exclosure is constructed. Between 1988-2000, a minimum of 15 nests was predated before an exclosure was erected. To protect the nest while eggs are being laid, a mini-exclosure may be used. Recent use (1999 and 2000) of mini-exclosures during egg laying protects the nest during this vulnerable period.
In 1999, several nests occurring in low-lying areas were at risk of inundation. These nests were elevated up to 30 cm in height by augmenting existing locations with mounds of gravel and sand. This technique was successful and prevented inundation and nest washout. Each of these nests hatched and fledged offspring.