Beach stone-curlew (Esacus magnirostris) - critically endangered species listing

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the Beach Stone-curlew Esacus neglectus Mathews, 1912 as a CRITICALLY ENDANGERED SPECIES in Part 1 of Schedule 1A of the Act, and as a consequence, to omit reference to Esacus neglectus Mathews, 1912 from Part 1 of Schedule 1 (Endangered species) of the Act. Listing of Critically Endangered species is provided for by Part 2 of the Act.

This species is now known as Esacus magnirostris Vieillot, 1818
[NSW Government Gazette No. 113, 25 November 2011, Page 6715]

NSW Scientific Committee - final determination

The Scientific Committee has found that:

1. The Beach Stone-curlew Esacus neglectus Mathews, 1912 is a large thickset grey-brown shorebird with a massive, yellow-based bill, a black and white face pattern; yellow eyes; a brown and white stripe on the forewings; and bold black and white patches on the wingtips in flight. It is 50 cm in length, with a wingspan of 100 cm.

2. The Beach Stone-curlew is restricted to the littoral zone of beaches and estuaries, where it nests on the ground just above the tideline. It is distributed around the tropical Australian coasts, and extends to Asia. In NSW breeding birds are confined to the North Coast as a single population, although Beach Stone-curlews are known to disperse as far as the Victorian border and have possible dispersal and genetic interchange across the NSW-Queensland border (Rohweder 2003).

3. A recent survey in NSW counted 13 adults at eight sites, plus one fledgling and two chicks (Rohweder 2003). Although the survey mainly targeted sites where the species was previously known to breed, there is a relatively high level of confidence in this estimate because the sites were each surveyed intensively, occupied locations have been known to ornithologists for decades and the surveyor widely sought unpublished observations. Furthermore the limited area of linear beaches improves the accuracy of visual searches. Rohweder (2003) allows that his survey effort may have missed some stone-curlews, yet clearly the total number of mature birds in NSW is extremely low.

4. The Australian population is believed to be stable (Garnett & Crowley 2000). Although the numbers in NSW were thought to have increased slightly over the past decade (Rohweder 2003), the different number of birds in Rohweder’s survey (13 adults) compared with earlier estimates of 10 birds (Smith 1991) may be related to survey effort.

5. The eight known sites with Beach Stone-curlews are dispersed among the major river estuaries: Richmond River, Belongil Creek (historically), Clarence River, Sandon River, Wooli River, Corindi River, Nambucca River and Manning River. Resident adults are sedentary and each occupied site is separated by 10 to 150 km (mostly 20-50 km) (Rohweder 2003). Single transient birds which are probably dispersing juveniles have been observed at several locations between Sydney and the Victorian border, remote from known breeding sites. It is likely that similar levels of dispersal occur in northern NSW.

6. Much littoral and estuarine habitat in NSW has been and continues to be destroyed and degraded by coastal development and human population increases. Remaining habitat is at risk of disturbance by human recreational activities (including recreation vehicles) and dogs. Other threats include nest or chick predation by foxes and feral pigs. ‘Predation, habitat degradation, competition and disease transmission by Feral Pigs, Sus scrofa Linnaeus 1758’, and ‘Predation by the European Red Fox Vulpes vulpes (Linnaeus,1758)’ are listed as Key Threatening Processes under the NSW Threatened Species Conservation Act 1995.

7. The Beach Stone-curlew is listed as Vulnerable in Queensland, but is not otherwise listed as threatened nationally or in other Australian states.

8. The Beach Stone-curlew Esacus neglectus Mathews, 1912 is eligible to be listed as a Critically Endangered species as, in the opinion of the Scientific Committee, it is facing an extremely high risk of extinction in New South Wales in the immediate future as determined in accordance with the following criteria as prescribed by the Threatened Species Conservation Regulation 2002:

Clause 17

The total number of mature individuals of the species is observed, estimated or inferred to be:

(a) extremely low

Dr Richard Major
Chairperson
Scientific Committee

Proposed Gazettal date: 31/07/09
Exhibition period: 31/07/09 - 25/09/09

References:

Garnett S, Crowley G (Eds) (2000) ‘The action plan for Australian birds 2000.’ (Environment Australia: Canberra)

Rohweder DA (2003) A population census of Beach Stone-curlews Esacus neglectus in New South Wales. Australian Field Ornithology 20, 8-16.

Smith P (1991) ‘The biology and management of waders (suborder Charadrii) in New South Wales.’ Species Management Report No. 9, NSW NPWS, Hurstville.