Insights from long-term shorebird monitoring for tracking change in ecological character of Australasian Ramsar sites

The Ramsar Convention is the centrepiece of international efforts for wetland conservation, aiming to maintain the ecological character of wetlands through holistic ecosystem management. Here, we review studies on shorebird populations at individual Australasian Ramsar sites and compare these against original listings under Criterion 6 to determine if there have been potential changes in ecological character. One to 12 migratory shorebird species have declined at four New Zealand and 18 Australian Ramsar sites over a 12 to 36-year period, resulting in 22 species (at 13 sites) no longer reaching Criterion 6 thresholds for Ramsar designation. In addition, 10 species at six Australian sites had exceeded the Limits of Acceptable Change. Despite these concerning results, there were remarkably few published site-based determinations of listed shorebird species' trends (and even fewer that were ≤5 years old). This is especially surprising since shorebird populations are regularly monitored at 27 out of 35 Australasian Ramsar sites (listed on the basis of one or more shorebird species). Thus, despite the volume of data available for analysis, long-term shorebird monitoring provides only limited insights about Ramsar ecological character. The value of these data would be greatly enhanced through complementary monitoring of other ecological characters at sites, particularly where shorebird populations provide early warning signs of potential deterioration. The main impediment to achieving a good understanding of how Ramsar sites are changing in Australasia appears to be a lack of analysis and centralised system for data and analytics, rather than a lack of monitoring data.