BIRD POPULATIONS - Birdpop.org

BIRD POPULATIONSA journal of global avian demography and biogeographyVolume 10 2010 (2009-2010)REPORTS OF AVIAN MONIOTORING PROGRAMSINTRODUCTION TO THE REPORTSStandardized broad-scale bird-bandingprograms (or bird-ringing programs as they areknown in Europe and elsewhere in the easternhemisphere) are an important component ofnational and international integrated avianmonitoring efforts. Such programs include theMonitoring Avian Productivity and Survivorship(MAPS) program in North America andthe Constant Effort Sites (CES) schemes inBritain and a number of other Europeancountries, and provide critical information onpost-fledging productivity and annual apparentadult survival rates. Despite the rich spatialstructure of the data provided by theseprograms and widespread interest in understandingspatial patterns of populationprocesses, little attention had been paid tospatial modeling of demographic rates. Recently,however, researchers at The Institute for BirdPopulations and the USGS Patuxent WildlifeResearch Center implemented Bayesianhierarchical analyses of a spatial autoregressivemodel based on the transient Cormack-Jolly-Seber (CJS) capture-recapture model to providespatially explicit and year-specific survival andresidency probabilities for Wood Thrush(Saracco et al. 2010. Ecology 91:1885-1891) andCommon Yellowthroat (Saracco et al. 2010. J.Ornithology, Online First, 10 August) from 12years (1992-2003) of MAPS data.Most previous studies that applied transientCJS models to capture-recapture data had largelybeen concerned with reducing the negative biasof transient individuals on survival estimates.Little attention had been paid to spatial ortemporal modeling of residency probabilityitself. The clear spatial patterns in residencyprobability revealed by these recent studies,however, suggest that the residency parameterhas important ecological relevance. Indeed, forboth Wood Thrush and Common Yellowthroat,these recent spatial autoregressive modelsshowed that spatial variation in survival andresidency tended to be independent of eachother. Areas where survival probability was highand residency probability was low could suggesta combination of good non-breeding seasonconditions and breeding habitat limitation. Incontrast, areas with low survival and highresidency could suggest areas where individualsexperienced low survival due to poor nonbreedingseason conditions, with subsequentample opportunity for new territory establishment(and thus few floaters).Clearly, the spatial modeling of avian survivaland residency probabilities, and of productivityand recruitment rates, especially in relationshipto climate, weather, and habitat, can providevaluable data useful for informing conservationand management. Such data can provide insightsinto causes of avian population trends, can helpidentify areas where problems are acute andareas where they will be further exacerbated byclimate change, can lead both to managementstrategies for reversing population declines andto adaptation strategies for climate change, andcan provide a means for evaluating the effectivenessof conservation, management, and adaptationstrategies. This will only happen, however,with continued spatially-extensive avianpopulation and demographic monitoring, which,in turn, will require long-term commitments of[88]