MoSI (Monitoreo de Sobrevivencia Invernal): assessing habitat-specific overwintering survival of neotropical migratory landbirds

Recent evidence suggests that population declines in many Neotropical-wintering migratory landbird species are caused by habitat loss and degradation on their wintering grounds. Such habitat loss and degradation can lower overwintering survival rates and cause surviving birds to leave their wintering grounds in poor physical condition, leading to high mortality during spring migration and low breeding productivity. Large-scale, long-term data on winter demographic parameters of these species and linkages between those parameters and winter habitat characteristics are urgently needed to understand the population dynamics of these migratory landbirds and guide management and conservation efforts for them. We established the MoSI (Monitoreo de Sobrevivencia Invernal) Program to fill this data gap. The objectives of MoSI are: (1) to assess habitat-, age-, and sex-specific overwintering survival rates and late winter physical condition for a suite of target species in a variety of winter habitats by applying state-of-the-art mark-recapture models to data collected from a network of standardized mist-netting and bird-banding stations throughout Mexico, Central America, and the Caribbean; (2) to use these data to formulate management plans for these species on their winter grounds; and (3) to use the MoSI network to facilitate feather collection for DNA and stable isotope analyses that aim to link breeding and wintering populations of these species. We have initiated a five-year pilot project aimed at evaluating, enhancing, and expanding the MoSI Program, and have created partnerships with 20 organizations and individuals in Mexico, Central America, and the Caribbean who operated 29 MoSI stations during the winter of 2002-03, the first year of this pilot project. We suggest that a successful MoSI Program can provide useful information on winter demographic parameters of resident, as well as migratory, Neotropical landbird species, and can be expanded northward into southern U.S. to address these same issues in temperate-wintering migratory species