Hunter Estuary


Year of compilation: 2008

Site description
The IBA contains the adjacent lower Hunter Estuary (with the boundary including all intertidal areas and swamps used by the key shorebirds and Australasian Bittern) and Hexham Swamp. The Hunter Estuary is recognised as the most important area in NSW for shorebirds (Smith 1991). As many as 4,800 migratory shorebirds have been recorded by Straw (2000). The IBA contains the Ramsar listed 2926 hectare Kooragang Nature Reserve, the North Arm of the Hunter River, from Hexham to Stockton Bridge, and associated wetlands. A large shallow circular bay to the north, Fullerton Cove, provides the main shorebird foraging site in the estuary. The North and South Arms surround Kooragang Island, an important foraging and roosting area for shorebirds and waterfowl. The Kooragang Dykes and Stockton Sandspit, located immediately upstream of Stockton Bridge are the most important sites for the majority of roosting shorebirds in the estuary. Most of the estuary is covered by tidal ponds, saltmarsh and mangoves. Tides at Kooragang Island range from 0.1m to 2m, average annual rainfall at Williamtown is 1088 mm and annual mean temperature ranges from 12 to 23 oC. Hexham Swamp is one of the largest freshwater swamps on the coast of New South Wales, and comprises about 45 per cent of all the remaining freshwater wetland habitat in the Hunter Valley. This section of the IBA is estimated to cover 2100ha. The swamp also contains estuarine habitat (eastern part adjacent to the Hunter River) which forms a strong ecological link with the western end of Kooragang Nature Reserve through Ash Island. Hexham Swamp Nature Reserve comprises about 900 hectares of Hexham Swamp. Freshwater swamps in the nature reserve are contiguous with Pambalong Nature Reserve to the west, The Hunter Wetlands Centre to the southeast and Newcastle Wetlands Reserve also to the southeast.

Key biodiversity
Major non-breeding foraging site for migratory waders such as Eastern Curlew, Whimbrel, Bar-tailed Godwit, Black-tailed Godwit, Great Knot, Red Knot, Terek Sandpiper, Grey-tailed Tattler, Common Greenshank, Marsh Sandpiper, Sharp-tailed Sandpiper, Curlew Sandpiper, Red-necked Stint, Pacific Golden Plover, Double-banded Plover and Latham’s Snipe. Non-migratory waders include Red-necked Avocet, Black-winged Stilt, Red-capped Plover, Pied Oystercatcher, Sooty Oystercatcher and occasional Australian Painted Snipe. Terns include Whiskered Tern, Gull-billed Tern and Caspian Tern. Waterfowl include Australasian Grebe, Hoary-headed Grebe, Musk Duck, Pink-eared Duck, Hardhead Australasian Shoveler, Grey Teal, Chestnut Teal, Blue-billed Duck and Freckled Duck. Raptors include Osprey, Wedge-tailed Eagle, White-bellied Sea-Eagle, Whistling Kite, Swamp Harrier, Spotted Harrier, Brown Goshawk, Peregrine Falcon, Australian Hobby, Brown Falcon, Black Falcon, Nankeen Kestrel, Black-shouldered Kite, and the most southerly occurrence of the Brahminy Kite. The Black-necked Stork is an occasional visitor. Red-backed Button-quail and Grass Owls have been recently recorded; both are at their southernmost limit of occurrence. Thousands of Australian White Ibis and a lesser number of Glossy Ibis roost at Hexham Swamp, which supports breeding colonies of Great Egret, Little Egret, Cattle Egret, Australian White Ibis and cormorants, small numbers of Magpie Geese and a roost of Rufous Night-Herons.

Non-bird biodiversity: Remnant dry littoral rainforest, small stands of Casuarina forest, extensive and expanding mangroves and decreasing saltmarsh. The endangered Green and Golden Bellfrog. Many species of microchiropteron bats. A variety of fish and decapod crustacean species. Hexham Swamp hosts 53 mammal species, 14 reptile species, 11 frog species, 6 prawn and shrimp species and 32 fish species.



Pressure/threats to key biodiversity
Mangrove encroachment onto mudflats and saltmarsh needs to be controlled by removal of mangroves and continued management of flow control structures. Industry, infrastructure and infilling must not be allowed to impact the habitat or hydrology of the site. Manage inundation of Hexham Swamp using floodgates on Ironbark Creek and weirs beside railway line to ensure a mosaic of wetland types and water levels.

Conservation responses/actions for key biodiversity
The Kooragang Wetland Rehabilitation Project has been operating for more than 10 years. 2 Honours theses on Bar-tailed Godwits, a PhD thesis on wader ecology and another PhD on hydrology. Monthly surveys of birds in estuary by the Hunter Bird Observers Club. Rehabilitation of Stockton Sandspit by joint cooperation of KWRP, NPWS and HBOC. Rehabilitation of Sandy Is and Smiths Is by NPWS. Installation of artificial roost platforms in Fullerton Cove by NPWS. Rehabilitation of Swan, Wader and Milhams Pond on Ash Is (joint project of HBOC and KWRP). Reintroduction of tidal flow to the Tomago wetlands (NPWS & KWRP). National Parks and Wildlife Service (1998) - Kooragang Nature Reserve and Hexham Swamp Nature Reserve Plan of Management. National Parks and Wildlife Service (2004) - Pambalong Nature Reserve Plan of Management. The Wetland Centre (2003) - Plan of Management for public education and wetland rehabilitation of the Hunter Wetlands Centre. Hunter Central Rivers CMA commissioned WBM Oceanics (2005) to assess environmental impacts of reinstating tidal inundation of Hexham Swamp by managing floodgates on Ironbark Creek.

Protected areas
Kooragang Nature Reserve

Hexham Swamp Nature Reserve

Pambalong Nature Reserve

Newcastle Wetlands Reserve Nature Reserve

The Hunter Wetlands Centre Nature Reserve

Land ownership
Hunter Estuary: NSW State Government, Regional Land Management Corporation, private. Hexham Swamp: Hunter Central Rivers CMA, Newcastle City Council, Shortlands Wetlands Centre Ltd, NPWS (NSW State govt), Hunter District Water Board, Australian Rail Track Corporation, Broadcast Australia Ltd, State of NSW, private ownership.

Site access / Land-owner requests


Acknowledgements
Hunter Bird Observers Club and Max Maddock have collected much of the bird data. The nomination was prepared by Chris Herbert and Elizabeth Crawford.


Recommended citation
BirdLife International (2022) Important Bird Areas factsheet: Hunter Estuary. Downloaded from http://www.birdlife.org on 26/06/2022.