Three long-term mark and recapture/resight data sets of individually marked
Semipalmated Plovers (Charadrius semipalmatus) were analyzed using Cormack-Jolly-
Seber models. Data came from two breeding populations (Churchill, Manitoba, Canada,
n=982, and Egg Island, Alaska, USA, n=84) and one overwintering population
(Cumberland Island, Georgia, USA, n=62). For Alaska and Georgia, time-invariant
models were best-supported, giving annual survival estimates of 0.67 (95%C.I.: 0.58-
0.76) and 0.59 (95%C.I.: 0.49-0.67) respectively. Data from Manitoba supported a timedependent
model: survival estimates varied from 1.00 to 0.36, with lowest estimates from
recent years, supporting observations of local population decline. Seasonal survival
analysis of the Georgia population indicated lower mortality during winter (monthly
Φoverwinter: 0.959, 95%CI: 0.871-0.988; for 6 month period Φoverwinter: 0.780 (0.440-0.929))
than during combined breeding and migratory periods (monthly ΦBreeding+Migration: 0.879
(0.825-0.918); for 8 month ΦBreeding+Migration: 0356 (0.215-0.504)). I recommend, based on
high resight rates, continued monitoring of survival of wintering populations, to
determine potential range-wide population declines.
Keywords: survival, longevity, mortality, shorebird, overwinter, breeding, migration, life
cycle
Author Keywords: life cycle, longevity, mortality, non-breeding, shorebird, survival