Revision of the East Asian-Australasian Flyway Population Estimates for 37 listed Migratory Shorebird Species

austgov-inline

Australian Government


Revision of the East Asian-Australasian Flyway (EAAF) Population Estimates for 37 listed Migratory Shorebird Species (Hansen et al. prepared for the Department of the Environment, 2016)


Migratory shorebirds present a particular conservation challenge because their patterns of movement take them across multiple international boundaries, in some cases almost spanning the globe. They utilise different sites in different countries at different times of the year, and conservation of these species therefore requires the management of the suite of sites that are important to them. To identify important habitat in Australia count data and population estimates are required.

Under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act), ‘important habitat’ is a key concept for migratory species, as identified in EPBC Act Policy Statement 1.1 Significant Impact Guidelines – Matters of National Environmental Significance 2009. Defining this term for migratory shorebirds in Australia is important to ensure that habitat necessary for the ongoing survival of the 37 species is appropriately managed.

Important habitats in Australia for migratory shorebirds under the EPBC Act include those recognised as nationally or internationally important. The widely accepted and applied approach to identifying internationally important shorebird habitat throughout the world has been through the use of criteria adopted under the Ramsar Convention.

According to this approach, wetland habitat should be considered internationally important if it regularly supports:

  • 1 per cent of the individuals in a population of one species or subspecies of waterbird or
  • a total abundance of at least 20,000 waterbirds.

Nationally important habitat for migratory shorebirds can be defined using a similar approach to these international criteria, i.e. if it regularly supports:

  • 0.1 per cent of the flyway population of a single species of migratory shorebird or
  • 2,000 migratory shorebirds or
  • 15 migratory shorebird species.

To determine population thresholds needed to identify important habitat, the Department previously used population estimates published in the Bamford et al., (2008) report. However, given these published figures are now almost 10 years old, they required updating.

The revised flyway population estimates use newly available data and different analytical approaches to those used in previous population estimate assessments. As a result, the numbers reported cannot be compared with previous estimates to draw conclusions about population trends. Dedicated analyses on data that are comparable over time are the only way to make conclusions about population trends. Any differences between the report’s figures and previous estimates reflect an increase in knowledge and information about migratory shorebirds in the EAAF over the past decade. They do not necessarily represent actual increases or decreases in population size and cannot be used to infer trends in this manner.

Latham’s Snipe (Gallinago hardwickii)*

Latham’s Snipe does not commonly aggregate in large flocks or use the same habitats as many other migratory shorebird species. Consequently, habitat important to Latham’s Snipe is not regularly identified using the process outlined above and different criteria are therefore necessary. Threshold criteria are still considered the best way to identify important sites in the absence of data sufficient for more rigorous methods. Important habitat for Latham’s Snipe is described as areas that have previously been identified as internationally important for the species, or areas that support at least 18 individuals of the species.

A summary of the revised population estimates for 37 migratory shorebirds.

Common NameFlyway population estimate1% Flyway Population0.1% Flyway Population
Asian Dowitcher14,00014014
Bar-tailed Godwit325,0003250325
Black-tailed Godwit160,0001600160
Broad-billed Sandpiper30,00030030
Common Greenshank110,0001100110
Common Redshank75,000-150,00075075
Common Sandpiper190,0001900190
Curlew Sandpiper90,00090090
Double-banded Plover19,00019019
Far Eastern Curlew35,00035035
Great Knot425,0004250425
Greater Sand Plover200,000-300,0002000200
Grey Plover80,00080080
Grey-tailed Tattler70,00070070
Latham’s Snipe*30,00030018*
Lesser Sand Plover180,000-275,0001800180
Little Curlew110,0001100110
Little Ringed Plover150,0001500150
Long-toed Stint230,0002300230
Marsh Sandpiper130,0001300130
Oriental Plover230,0002300230
Oriental Pratincole2,880,00028,8002880
Pacific Golden Plover120,0001200120
Pectoral Sandpiper1,220,000-1,930,00012,2001220
Pin-tailed Snipe170,0001700170
Red Knot110,0001100110
Red-necked Phalarope250,0002500250
Red-necked Stint475,0004750475
Ruddy Turnstone30,00030030
Ruff25,000-100,00025025
Sanderling30,00030030
Sharp-tailed Sandpiper85,00085085
Swinhoe’s Snipe40,00040040
Terek Sandpiper50,00050050
Wandering Tattler10,000-25,00010010
Whimbrel65,00065065
Wood Sandpiper130,0001300130

Original link: Revision of the East Asian-Australasian Flyway Population Estimates for 37 listed Migratory Shorebird Species (Australian Government)

Relevant links:

Comments are closed.