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Decreases in shorebird populations are increasingly evident worldwide, especially in the East Asian–Australasian Flyway (EAAF). To arrest these declines, it is important to understand the scale of both the problem and the solutions. We analysed an expansive Australian citizen-science dataset, spanning the period 1973 to 2014, to explore factors related to differences in trends among shorebird populations in wetlands throughout Australia. Of seven resident Australian shorebird species, the four inland species exhibited continental decreases, whereas the three coastal species did not. Decreases in inland resident shorebirds were related to changes in availability of water at non-tidal wetlands, suggesting that degradation of wetlands in Australia’s interior is playing a role in these declines. For migratory shorebirds, the analyses revealed continental decreases in abundance in 12 of 19 species, and decreases in 17 of 19 in the southern half of Australia over the past 15 years. Many trends were strongly associated with continental gradients in latitude or longitude, suggesting some large-scale patterns in the decreases, with steeper declines often evident in southern Australia. After accounting for this effect, local variables did not explain variation in migratory shorebird trends between sites. Our results are consistent with other studies indicating that decreases in migratory shorebird populations in the EAAF are most likely being driven primarily by factors outside Australia. This reinforces the need for urgent overseas conservation actions. However, substantially heterogeneous trends within Australia, combined with declines of inland resident shorebirds indicate effective management of Australian shorebird habitat remains important. [ABSTRACT FROM AUTHOR]

The article discusses research on the implications of the staging behavior of Red Knot or Calidris canutus for monitoring its mass and population size in Delaware Bay. The researchers used mark-recapture techniques and resightings of birds that were marked in the previous year to monitor the staging behavior of the bird in the area. Using staging duration and mass gains of the birds, they estimated a passage population size of 18,000 Red Knots in 2004, which reached an average mass of 111 grams and an average gained mass at 7.2 grams per day.

The article discusses a study which investigated annual recapture and survival rates of two non-breeding adult populations of Roseate terns (Sterna dougallii) captured on the Great Barrier Reef in Queensland. Estimates of their population sizes are also presented. It has been observed that the average annual survival rate for the birds from the Asian population is higher than that of the other population of unknown breeding origin. A full description of the study site in the Swain Reefs is also presented.