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Summary1. Conservation and management of migratory waterbirds use flyway populations as the basic unit, and knowledge of the delineation, rate of exchange and gene flow between populations is fundamental. However, for the majority of global flyway populations, information is too fragmentary to address connectivity between populations and, hence, insufficient to inform management. 2. We investigated the demographic connectivity between the eastern (breeding in Svalbard and wintering in Denmark, the Netherlands and Belgium) and western (breeding in Greenland or Iceland and wintering in Britain) flyway populations of pink-footed geese Anser brachyrhynchus based on resightings of marked geese from both populations. Previous genetic analyses suggested a modest gene flow between the two populations. 3. Capture-recapture analysis conservatively estimated that mean annual movement probabilities were low (eastern to western population: 0Á071%, 95% CI = 0Á033-0Á15%; western to eastern: 0Á076%, 95% CI = 0Á031-0Á18%). Movement probability from eastern to western flyway populations increased in years with high snow cover in the southernmost winter range in Belgium. Life histories of exchanged individuals from eastern to western (32 different individuals during 1988-2010) revealed that the majority entered Britain via Belgium and the Netherlands during winter; some returned to the eastern population via Belgium and/or the Netherlands, others moved northwards in Britain during the spring and appear to have migrated directly from Britain (western population) to Norway (eastern population). None of the birds from the eastern population emigrated permanently, but some individuals turned up in Britain in consecutive years. Out of nine individuals switching from western to eastern flyway populations, three returned to Britain; the others were not subsequently resighted. An alternative winter strategy and spring flyway over Britain to Norway is suggested, used by hundreds to thousands of eastern birds, particularly following severe winters. Thus, the two populations currently appear to be demographically closed; low genetic connectivity probably reflects dispersal over longer time. 4. Synthesis and applications. Current initiatives to internationally manage the eastern population of pink-footed geese do not need to consider net immigration in predictive harvest models. For waterbirds in general, a targeted approach to evaluate connectivity, using classic marking studies in combination with molecular methods and focussed sampling on breeding grounds, is recommended to better underpin management decisions at population levels.

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Harvested species population dynamics are shaped by the relative contribution of natural and harvest mortality. Natural mortality is usually not under management control, so managers must continuously adjust harvest rates to prevent overexploitation. Ideally, this requires regular assessment of the contribution of harvest to total mortality and how this affects population dynamics.To assess the impact of hunting mortality on the dynamics of the rapidly declining Baltic/Wadden Sea population of common eiders Somateria mollissima, we first estimated vital rates of ten study colonies over the period 1970–2015. By means of a multi‐event capture–recovery model, we then used the cause of death of recovered individuals to estimate proportions of adult females that died due to hunting or other causes. Finally, we adopted a stochastic matrix population modeling approach based on simulations to investigate the effect of past and present harvest regulations on changes in flyway population size and composition.Results showed that even the complete ban on shooting females implemented in 2014 in Denmark, where most hunting takes place, was not enough to stop the population decline given current levels of natural female mortality. Despite continued hunting of males, our predictions suggest that the proportion of females will continue to decline unless natural mortality of the females is reduced.Although levels of natural mortality must decrease to halt the decline of this population, we advocate that the current hunting ban on females is maintained while further investigations of factors causing increased levels of natural mortality among females are undertaken. Synthesis and applications. At the flyway scale, continuous and accurate estimates of vital rates and the relative contribution of harvest versus other mortality causes are increasingly important as the population effect of adjusting harvest rates is most effectively evaluated within a model‐based adaptive management framework.