Pittwater Waterbird Habitat

Survey and Mapping

K. Brandis, H. Watson and S. Ryall

Australian Wetlands and Rivers Centre

University of New South Wales

August 2012

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Table of Contents

Project background .................................................................................................................... 4

Waterbirds ................................................................................................................................. 5

Shorebirds .................................................................................................................................. 6

Shorebird habitat requirements ................................................................................................ 6

Migratory waterbird conservation and management ............................................................... 8

Migratory waterbirds and the East Asian - Australasian Flyway ........................................... 8

International cooperation ...................................................................................................... 8

JAMBA and CAMBA ................................................................................................................ 9

ROKAMBA .............................................................................................................................. 9

Protecting species in Australia ............................................................................................. 10

Methods ................................................................................................................................... 11

Existing data and information gaps ..................................................................................... 11

Study site .............................................................................................................................. 12

Survey methodology ............................................................................................................ 12

Data collection ..................................................................................................................... 13

Boat Surveys ..................................................................................................................... 14

Ground Surveys ................................................................................................................ 14

Results ...................................................................................................................................... 19

Species abundance and diversity ......................................................................................... 19

Waterbird habitat ................................................................................................................ 32

Habitat use ........................................................................................................................... 32

Estuarine Habitats ................................................................................................................ 40

Disturbance .......................................................................................................................... 43

Discussion................................................................................................................................. 45

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Climate change and sea level rise ........................................................................................ 45

Key findings .......................................................................................................................... 51

Recommendations ............................................................................................................... 51

References ............................................................................................................................... 52

Appendix 1: Table of Aquatic Birds for the Lower Hawkesbury River, Patonga Creek, Broken

Bay, Pittwater, and Brisbane Water, 1967-2011 ..................................................................... 53

Table of Figures

Figure 1 Waterbird survey sites in the Pittwater Estuary (see Table 1). ................................. 15

Figure 2 Waterbird counts per species per survey .................................................................. 23

Figure 3 Passerine counts per species per survey. .................................................................. 27

Figure 4 Raptor counts per species per survey. ....................................................................... 28

Figure 5 Total bird abundance (blue-boat survey; green–ground survey) and species diversity

(red) recorded for each survey. ............................................................................................... 28

Figure 6 Total waterbird abundance (blue-boat survey; green–ground survey) and waterbird

species diversity (red) recorded for each survey. .................................................................... 29

Figure 7: Cumulative species curve ......................................................................................... 29

Figure 8 Species diversity by survey site .................................................................................. 30

Figure 9 Number of species observed foraging in using each habitat type. ........................... 35

Figure 10 Number of species observed roosting in each habitat type. ................................... 35

Figure 11 Dominant type of habitat used at each survey site. Note this is not a habitat

classification of survey sites, as most sites have several habitat types present e.g. man-made

roosts and sandy beaches. ....................................................................................................... 39

Figure 12 Waterbird foraging and roosting habitat in the Pittwater Estuary. ........................ 42

Figure 13 Frequency of waterbird disturbance types recorded in Pittwater Estuary. ............ 43

Figure 14 Counts of different disturbance types at survey sites. ............................................ 44

Figure 15 Waterbird habitat areas likely to be impacted by sea level rise. ............................ 48

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Project background

Waterbirds, both locally occurring and migratory, are an integral part of the ecosystem of

the Pittwater estuary. Pittwater is currently one of the few remaining known habitats of the

Bush Stone-curlew (an Endangered Species) in the Sydney Region. With a known pair in

Careel Bay. Despite the ecological significance of waterbirds, there is little baseline data on

their distribution. Being dependent on estuaries they are vulnerable to, and indicative of,

degradative processes. Climate change and sea level rise and changes to hydrodynamics

have the potential to modify the condition and extent of habitat available for waterbirds in

Pittwater.

Pittwater Council currently has, in draft form, the Pittwater Foreshore Floodplain Mapping

of Sea Level Rise Impacts report. The report provides a GIS layer identifying weekly, yearly

and extreme tides predicted for 2010, 2050 and 2100. The aim of the report is to review,

update and expand the current Estuarine Planning Level Mapping, to incorporate adopted

sea level benchmarks, within the framework of the NSW Floodplain Risk Management

Process. This will offer information about the likely current and future impacts of tidal

inundation due to sea level rise around the foreshore of the Estuary.

This project is aimed at building on the current and proposed waterbird studies by Hornsby

Council occurring within the management area of the Lower Hawkesbury Estuary

Management Plan. Hornsby also aims to identify where important migratory and estuarine

waterbird populations may be lost or re-established as a result of climate change. This

project will extend Hornsby’s work to a regional scale.

Pittwater extends from Mona Vale and Warriewood in the south, along the eastern ridge of

the Peninsular leading to Palm Beach and along the western ridge leading to West Head.

Pittwater estuary and surrounding lands contain a wide range of estuary habitats. These

include rocky shores, mangroves, seagrasses, saltmarsh, sandy shoals (as both fluvial deltas

and a flood tide marine shoal) and deep open water environments.

The Pittwater Native Fauna Management Plan (Ecotone Ecological Consultants June 2010)

states that some of the species which have historically visited and currently visit the area

are listed as Threatened Species. They are also listed on the China-Australia Migratory Bird

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Agreement (CAMBA), Japan-Australia Migratory Bird Agreement (JAMBA) and the Republic

of Korea-Australia Migratory Bird Agreement (ROKAMBA). Under the terms of these

agreements Statutory Authorities in Australia are obliged to protect these birds from direct

threats and protect their habitats from degradation.

The plan also identified a number of historical and anecdotal records which indicated that

the area has held large numbers of migratory wading birds in the past. These include

Eastern Curlew (Numenius madagascariensis), Whimbrel (N. phaeopus), Bar-tailed Godwit

(Limosa lapponica), Common Greenshank (Tringa nebularia), Grey-tailed Tattler (T.

brevipes), Red Knot (Calidris Canutus) and Sharp-tailed Sandpiper (C. acuminate). The site

may possibly have been visited by Curlew Sandpiper (C. ferruginea), Terek Sandpiper (Xenus

cinereus), Red-necked Stint (C. ruficolis), Common Sandpiper (Actitis hypoleucos) and Pacific

Golden Plover (Pluvialis fulva).

Despite these data, there are significant knowledge gaps in estuarine bird distributions and

the future impacts of sea level rise. With data collected from both Hornsby and Pittwater we

will have a much greater picture of the impacts of climate change on estuarine wetlands and

migratory waterbirds on a regional scale.

Pittwater Council received a grant from the NSW Office of Environment and Heritage

Estuary Management Program to investigate the impacts of climate change on estuarine

wetland and migratory waterbirds in the Pittwater estuary. In undertaking such an

investigation baseline data survey is required.

Waterbirds

Waterbirds are a large and diverse group of birds including ducks, geese and swans (Order

Anseriformes); grebes (Order Podicipediformes); pelicans, darters and cormorants (Order

Pelecaniformes); herons, egrets, bitterns, ibis and spoonbills (Order Ciconiiformes); rails,

moorhens and coots (Order Gruiformes); and waders (Order Charadriiformes). Most are

exclusive to freshwater habitats such as rivers, lakes, dams and wetlands, however many

species can also be regularly found in saltwater, e.g. cormorants and many migratory

waders.

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While many species of waterbirds are not migratory, they can move large distances in

search of suitable habitat. These species are termed nomadic as their movements are not

necessarily seasonal and are determined by habitat availability not seasonal changes. These

species include ibis, pelicans, ducks, egrets, herons, cormorants, spoonbills and swans.

Shorebirds

Shorebirds, or waders, belong to the order Charadriiformes, excluding the Laridae (gulls and

terns). Typically birds of wetlands, shorebirds can occur in a wide range of habitats and are

diverse in their habitat preferences and life history. Many shorebirds are migratory

travelling up to 26,000 km each year between Australian and their breeding grounds in

Siberia, northern China and Alaska. A total of 63 shorebird species have been recorded in

NSW (Smith 1991). Thirty-four species are considered to occur in the Sydney region

(Appendix 1). Of these, 25 species are migratory; all breeding in northern hemisphere

except Double-banded Plover, which breeds in New Zealand. Thirteen migratory species

regularly recorded in Sydney area, the rest only occur occasionally or rarely. The remaining

nine shorebird species are resident within Australia, including species that breed locally,

breed on offshore islands, or that are nomadic and may travel great distances in response to

environmental conditions (Nebel, Porter et al. 2008). Data for shorebird abundance in the

lower Hawkesbury River are very limited.

Shorebird habitat requirements

Shorebird species use a variety of different wetland habitats for foraging, typically in or near

water, wading up to a depth of around 15cm for long-legged species. Shorebirds occur in

marine habitats including ocean beaches, rocky coastlines, intertidal mudflats. They also

occur in coastal wetland habitats and river estuaries, including saltmarsh and mangroves,

and in freshwater wetland habitats such as marshes, the margins of lagoons and along

creeks. Shorebirds will also utilise other potential habitats within urbanised areas including

parks with open grassland, golf courses, other types of open/undeveloped land, and may

use artificial structures as roosting habitat.

Some species of shorebirds are habitat generalists, while other species have specific

requirements for habitat type, and may be limited to either marine or freshwater habitats.

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Most shorebird species prefer open habitats, and will avoid areas with tall vegetation,

although there are some species that use vegetated areas for cover or foraging (Latham’s

Snipe, Common Sandpiper), or for roosting (in mangroves - Whimbrel, Grey-tailed Tattler).

Species that forage in tidal habitats also require suitable alternative habitat as a high-tide

refuge. Shorebirds may roost in a range of different habitats and may travel some distance

from their feeding grounds to a suitable roost site. Roosts are usually in a location with an

open aspect as one of the most important factors is avoidance (or early detection) of

predators.

Shorebirds engage in a range of foraging strategies and will take a variety of prey items.

Some species use visual foraging to pick small invertebrates off the surface of the substrate,

others use their long pressure-sensitive bills for probing deep into mud to obtain buried

shellfish, worms or other invertebrates. Many species feed during the night, and for some

species - particularly plovers - this is their primary period for foraging. Foraging periods for

species of tidal habitats are constrained by the tide cycle rather than daylight.

Another important function of habitat for shorebirds is as a stop-over site while birds are on

migration. Similarly, coastal habitats can provide crucial alternative habitat, for birds of

resident and migratory species, when there are drought conditions inland.

Within the Hawkesbury River area, the principal shorebird habitats are the estuarine

mudflats exposed during low tide, mangroves, and other brackish or freshwater wetland

habitats occurring in the vicinity of the river.

Factors that affect habitat suitability for shorebirds include:

Prey availability – abundance/density of prey, distribution may be patchy

Disturbance – presence of actual or perceived predators, including humans

Patch size – small areas of habitat may be used by shorebirds only if there is

sufficient additional habitat nearby

Distance to other habitats - lack of suitable roosting locations might preclude use of

otherwise suitable foraging habitat.

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Availability of high-quality foraging habitat – this is critical for the period preceding

migration, there is evidence that birds within the Sydney area may move elsewhere

for the final stages of pre-migration conditioning

Migratory waterbird conservation and management

The federal government Department of Sustainability, Environment, Water, Population and

Communities is the overarching authority to manage and conserve biodiversity in Australia.

The Department provides the following information on migratory shorebirds

(http://www.environment.gov.au/biodiversity/migratory/waterbirds/index.html)

Australia provides critical non-breeding habitat for millions of migratory waterbirds each

year. To ensure their conservation the Australian Government has fostered international

cooperation through a range of important agreements, including the Ramsar Convention

and the Convention on Migratory Species, bilateral agreements with Japan, China and the

Republic of Korea, and through the recently launched East Asian — Australasian Flyway

Partnership.

Migratory waterbirds and the East Asian - Australasian Flyway

Migratory waterbirds include species such as plovers, sandpipers, stints, curlews and snipes.

These birds make round trip migrations of up to 26,000 km each year between their

breeding grounds in the northern hemisphere and their non-breeding areas in the south.

These trips are made in several weeks, with brief stops at staging sites along the way to rest

and refuel for the next leg of their journey. The corridor through which these waterbirds

migrate is known as the East Asian - Australasian Flyway (the Flyway). It extends from

within the Arctic Circle, through East and South-east Asia, to Australia and New Zealand.

Stretching across 22 countries, it is one of 8 major waterbird flyways recognised around the

globe.

International cooperation

For over 30 years, Australia has played an important role in international cooperation to

conserve migratory birds in the Flyway, entering into bilateral migratory bird agreements

with Japan in 1974 (JAMBA), China in 1986 (CAMBA) and most recently the Republic of

Korea in July 2007 (ROKAMBA). Each of these agreements provide for the protection of

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migratory birds from take or trade except under limited circumstances, the protection and

conservation of habitats, the exchange of information, and building cooperative

relationships.

JAMBA and CAMBA

The first two bilateral agreements relating to the conservation of migratory birds were

formed with the Government of Japan in 1974 and the People’s Republic of China in 1986.

The JAMBA and CAMBA agreements list terrestrial, water and shorebird species which

migrate between Australia and the respective countries. In both cases the majority of listed

species are shorebirds.

Both agreements require the parties to protect migratory birds by:

limiting the circumstances under which migratory birds are taken or traded

protecting and conserving important habitats

exchanging information

building cooperative relationships

The JAMBA agreement also includes provisions for cooperation on the conservation of

threatened birds. Australian government and non-government representatives meet every

two years with Japanese and Chinese counterparts to review progress in implementing the

agreements and to explore new initiatives to conserve migratory birds.

ROKAMBA

In April 2002, Australia and the Republic of Korea agreed to develop a bilateral migratory

bird agreement similar to the JAMBA and CAMBA. The ROKAMBA agreement was signed in

Canberra on 6 December 2006. The agreement entered into force on 13 July 2007. The

ROKAMBA formalises Australia's relationship with the Republic of Korea in respect to

migratory bird conservation and provides a basis for collaboration on the protection of

migratory shorebirds and their habitat.

Multilateral cooperation on migratory bird conservation JAMBA, CAMBA and ROKAMBA

provide an important mechanism for pursuing conservation outcomes for migratory birds,

including migratory shorebirds. However, the bilateral nature of these agreements limits

their scope and ability to influence conservation across the flyway. Australia has therefore

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also encouraged multilateral cooperation for migratory bird conservation through the

Partnership for the East Asian-Australasian Flyway.

Protecting species in Australia

All migratory bird species listed in the annexes to these bilateral agreements are protected

in Australia as matters of national environmental significance under the Commonwealth

Environment Protection and Biodiversity Conservation Act 1999.

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Methods

Pittwater Council’s estuary waterbird habitat survey and mapping project aims to identify

important waterbird habitat and gather baseline data on waterbird populations within the

Pittwater estuary.

Existing data and information gaps

A review of existing information in Council reports indicates that there is little data on the

occurrence of waterbirds in the Pittwater estuary, with the exception of survey records for

Careel Bay.

Careel Bay has been recognised as the most significant area of estuarine wetlands in the

Pittwater LGA (Smith and Smith 1997). The most recent data is from bird surveys carried out

for Pittwater Council in 2006-7 (Coughlan 2008). Earlier surveys were completed in 2001

and 1997 (Smith and Smith 1997; Smith and Smith 2001), and Smith and Smith (1997)

compiled additional observations for Careel Bay dating back to 1971. These data provide a

relatively long-term record for the waterbird populations occurring at Careel Bay.

The Pittwater LGA native fauna management plan (Pittwater Council and Ecotone Ecological

Consultants 2010) incorporates additional data for bird species within the Pittwater LGA –

including species occurring in wetlands beyond the extent of the Pittwater estuary –but to

date there have been no systematic surveys of the estuarine region.

Waterbirds occur in other areas within the Pittwater estuary where suitable habitat exists. A

variety of substrate and vegetation types can be found across the estuary, including sandy

beaches, intertidal mudflats, mangroves, creeks, rocky shorelines, open water and seagrass

beds. These may provide habitat for a diverse range of waterbirds, although many patches

of habitat are small. The Pittwater estuary is also highly modified by humans - much of the

eastern shoreline is altered by urban development, undeveloped areas are frequently used

by people for recreation and there is a high level of boating activity on the water. However,

some waterbird species successfully exploit modified environments, and may be attracted

to developed areas for foraging opportunities, or to use man-made structures as alternative

habitat.

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This waterbird survey project determined the current distribution and abundance of

waterbirds across the Pittwater estuary. It also examined habitat use by waterbird species

to determine the specific areas used and their significance for meeting species’ habitat

requirements. This information will then be used to assess the potential impact of sea level

rise and associated habitat loss for waterbird species populations in the Pittwater estuary.

Study site

The Hawkesbury River is one of the major rivers of the coastal region of NSW. The Pittwater

Estuary on which this study focuses is located to the north of Sydney and includes the body

of water enclosed between West Head and Barrenjoey Head, the shoreline and adjacent

estuarine wetlands (Figure 1).

Survey methodology

We use the term ‘waterbirds’ to mean bird species that live on marine or fresh water or in

wetland habitats. This includes families of ducks, cormorants, grebes, rails, herons, ibis,

shorebirds, gulls, terns, pelicans, penguins and seabirds. We will also record the occurrence

of other bird species that are particularly associated with or restricted to estuarine habitats,

including raptors (e.g. White-bellied Sea Eagle, Osprey, Whistling Kite), kingfishers and

passerines (e.g. Mangrove Gerygone).

We identified areas with suitable habitat for waterbird species from maps and recent aerial

photos of the Pittwater estuary.

A site-based approach was used to collect survey data for the estuary. These data can be

used to examine local waterbird distribution and habitat use in detail, as well summarise

waterbird populations for the estuary as a whole. Survey sites are shown on a map of the

region in Figure 2 and listed in Table 1.

The nature of the Pittwater landscape means that two complementary methods are

required to survey for waterbirds: observations made by boat and from the land (Table 1).

Boat surveys allow open water habitats and continuous stretches of coastline to be

surveyed more readily, and are invaluable for reaching sites with no road access, or that are

otherwise difficult to access from the land. Land-based surveys are preferable for sites

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where shallow water makes it difficult to approach by boat, and where species may occur in

vegetated habitats away from open water.

The western side of Pittwater was surveyed by boat only, as there was limited road access,

while the eastern side was primarily surveyed from the land, however inaccessible sites

were surveyed by boat, and we aimed to include as many other eastern sites as possible

during boat surveys to maximise the number of visits for those sites.

Surveys were conducted during the months of January to June 2012. While this time period

was relatively short it aimed to coincide with visiting periods of migratory shorebirds to

eastern Australia. The length of the survey period should allow us to observe if there is

seasonal variation in waterbird species abundance during summer, autumn and early

winter. Migratory shorebirds will typically be present until late March, although immature

birds of some species (e.g. Eastern Curlew) may stay through the winter. Most other

waterbird species are Australian residents, although may have seasonal movements for

breeding and in response to local conditions.

Data collection

Surveys for waterbirds will be carried out by 1-2 experienced observers, using binoculars

and a telescope where necessary.

At each site we will identify all waterbird species, record the number present and the

habitat type where the birds are observed. We will observe the behaviour of the birds, and

record the predominant behaviour at the time of survey, as a means of determining habitat

use at that site. We expect to assign three categories for behaviour/habitat use: foraging

(feeding or actively searching for food), roosting (resting or preening), or active (engaged in

some other activity, such as walking or swimming). We will also record any other significant

activity if observed, such as breeding, or events where we observe disturbance to

waterbirds.

In addition, at each site we will record the time of the survey, the stage of the tide and

whether people or dogs are present, or any other observable factor that may affect whether

birds are present or absent at the site.

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We will also record the conditions on each survey day, including the time of high tide and

the maximum temperature, windspeed and rainfall during the survey period.

Boat Surveys

Boat surveys were conducted monthly using a boat with an outboard motor (Table 1).

Shorelines and open waters were surveyed. Surveys were conducted by two experienced

observers. Shorelines of major tributaries were surveyed from a slow moving boat travelling

at approximately 5 knots. Bays and inlets were surveyed from a stationary boat. Species

were observed using binoculars.

Boat surveys were conducted on a range of tides, including low and high tide to include both

potential low tide feeding sites and high tide roosting sites.

Ground Surveys

Ground surveys were conducted by two observers on foot. Ground surveys were conducted

on average once a month (Table 1). Species were observed using binoculars and telescope

when required.

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Figure 1 Waterbird survey sites in the Pittwater Estuary (see Table 1).

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Scotland Is.

Careel Bay

McCarrs Ck

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Barrenjoey

The Basin

Legend

Pittwater Estuary

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Intertidal flats

Mangroves

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Table 1 Sites surveyed for waterbirds, dates (2012) and survey type (blue – survey by boat; green – ground based survey).

Survey No. and date 1 2 3 4 5 6 7 8 9 10 11

27 Jan. 9 Feb. 18 Feb. 28 Feb. 6 Mar. 27 Mar. 3 April 27 April 2 May 31 May 1 June

1 Avalon Sailing Club

2 Barrenjoey Head - ocean

beach

3 Barrenjoey Head -

Pittwater beach

4 Barrenjoey Head - rocks

5 Bayview boat ramp

6 Bayview channel

7 Bayview Golf Course

8 Bayview Park

9 Bayview Spit

10 Bayview Yacht Racing

Association

11 Bonnie Doon Wharf

12 Browns Bay

13 Cabbage Tree Creek

14 Careel Bay

15 Careel Bay - end of

George St

16 Careel Bay north

17 Careel Bay wetlands

18 Church Point

19 Clareville Beach Reserve

20 Coasters Retreat

21 Currawong Beach

22 Elvina Bay

23 Florence Park

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24 Great Mackerel Beach

25 Little Lovett Bay

26 Longnose Bay

27 Longnose Point

28 Lovett Bay

29 Lucinda Park

30 Maybanke Cove

31 McCarrs Creek 1

32 McCarrs Creek 2

33 McCarrs Creek Reserve

34 Morning Bay

35 Newport

36 Newport Yacht Clubs

37 Scotland Island - south

38 Palm Beach golfcourse

39 Paradise Beach

40 Portugese Bay

41 Refuge Cove

42 Resolute Beach

43 Robotmown grass

44 Salt Pan Cove

45 Sandy Beach

46 NSW Maritime

47 Scotland Island - north

48 Snapperman beach reserve

49 Soldiers Point

50 Taylors Point Reserve

51 The Basin

52 Towlers Bay

18

53 Trehame Cove

54 West Head

55 West Head beach

56 Winnererremy Foreshore

Reserve

57 Woody Point

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Results

Species abundance and diversity

A total of 30 bird species were recorded during boat and ground surveys from January to

June 2012 (Table 2). This total included 25 waterbird species, two passerine species and two

species of raptor (Table 2). Two species are identified as migratory as listed under the EPBC

Act 1999, the White-bellied sea eagle (Haliaeetus leucogaster), and Eastern curlew

(Numenius madagascariensis). These species are also listed under the Japan-Australia

Migratory Bird Agreement (JAMBA), the China-Australia Bird Agreement (CAMBA) and/or

the Republic of Korea-Australia Migratory Bird Agreement (ROKAMBA) (Table 2).

Not all species were recorded on all surveys (Figure 2). Species encountered most frequently

throughout the survey period included: Silver gull, Masked lapwing, Little pied cormorant

and the White-faced heron. These species were observed on each survey. Records of

passerine species listed here were not the result of targeted surveys but were incidental

observations made during the course of waterbird surveys.

The most abundant species recorded was the Silver gull with a group of 50 individuals

recorded at Snapperman Beach Reserve on survey 7 (Figure 2).

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Table 2 Bird species recorded during Pittwater surveys January – June 2012. Species are identified into general groupings (waterbird, passerine and raptor), whether they are a migratory species under the EPBC Act 1999, and if they are listed on the Japan -Australia Migratory Bird Agreement (JAMBA), the China-Australia Bird Agreement (CAMBA) and the Republic of Korea-Australia Migratory Bird Agreement (ROKAMBA).

Common name Scientific name Waterbird Passerine Raptor Migratory species JAMBA CAMBA ROKAMBA

Australasian darter Anhinga navaehollandiae (melanogaster) x

Australasian gannet Morus serrator x

Australian pelican Pelecanus conspicillatus x

Australian white ibis Threskiornis molucca x

Australian wood duck Chenonetta jubata x

Azure kingfisher Ceyx (Alcedo) azureus

x

Black-winged stilt Himantopus himantopus x

Chestnut teal Anas castanea x

Crested tern Thalasseus (Sterna) bergii x

Domestic geese Anser anser domesticus x

Dusky moorhen Gallinula tenebrosa x

Eastern Curlew Numenius madagascariensis x

x x x x

Great cormorant Phalacrocorax carbo x

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Great egret Ardea ibis x x

Grey teal Anas castanea x

Little black cormorant Phalacrocorax sulcirostris x

Little pied cormorant Microcarbo (Phalacrocorax) melanoleucos x

Masked lapwing Vanellus miles x

Northern mallard Anas platyrhynchos x

Pacific black duck Anas superciliosa x

Pied cormorant Phalacrocorax varius x

Purple swamphen Porphyrio porphyrio x

Royal spoonbill Platelea regia x

Sacred kingsfisher Todiramphus sanctus

x

Silver gull Chroicocephalus (Larus) navaehollandiae x

Striated (Mangrove) heron Butorides (Ardeola) striata x

Whistling kite Haliastur sphenurus

x

White faced heron Egretta (Ardea) novaehollandiae x

22

White-bellied sea eagle Haliaeetus leucogaster

x

x

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Figure 2 Waterbird counts per species per survey

0

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s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

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Survey number

Australasian darter

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s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

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Survey number

Australasian gannet

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Australian pelican

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3

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Survey number

Australian white ibis

0

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4

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6

7

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

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Survey number

Australian wood duck

0

1

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

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un

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Survey number

Black-winged stilt

24

0

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s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

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Survey number

Chestnut teal

0

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Crested tern

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Survey number

Domestic geese

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Survey number

Dusky moorhen

0

1

2

3

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Eastern curlew

0

1

2

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Great cormorant

25

0

1

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Great egret

0

1

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Grey teal

0

1

2

3

4

5

6

7

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Hybrid duck

0

1

2

3

4

5

6

7

8

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Little black cormorant

0

5

10

15

20

25

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Little pied cormorant

0

5

10

15

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Masked lapwing

26

0

1

2

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Northern mallard

0

2

4

6

8

10

12

14

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10s11

Co

un

t

Survey number

Pied cormorant

0

1

2

3

4

5

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Pacific black duck

0

1

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Purple swamphen

0

10

20

30

40

50

60

70

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Silver gull

0

1

2

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Royal spoonbill

27

Figure 3 Passerine counts per species per survey.

0

2

4

6

8

10

12

14

16

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

White-faced heron

0

0.5

1

1.5

2

2.5

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Striated heron

0

1

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Azure kingfisher

0

1

2

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

Sacred kingfisher

28

Figure 4 Raptor counts per species per survey.

Figure 5 Total bird abundance (blue-boat survey; green–ground survey) and species diversity (red) recorded for each survey.

0

1

2

3

4

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey number

White-bellied sea eagle

0

1

2

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t Survey number

Whistling kite

0

20

40

60

80

100

120

140

160

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey

29

Figure 6 Total waterbird abundance (blue-boat survey; green–ground survey) and waterbird species diversity (red) recorded for each survey.

Figure 7: Cumulative species curve

0

20

40

60

80

100

120

140

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey

0

5

10

15

20

25

30

35

s1 s2 s3 s4 s5 s6 s7 s8 s9 s10 s11

Co

un

t

Survey

30

Figure 8 Species diversity by survey site

0

2

4

6

8

10

12

14

16

Ava

lon

Sai

ling

Clu

b

Bar

ren

joey

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ad -

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an b

each

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ren

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at M

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le L

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tt B

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gno

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t

Luci

nd

a P

ark

May

ban

ke C

ove

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arrs

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ek

1

McC

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Cre

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Res

erve

Mo

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g B

ay

New

po

rt

New

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t C

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s

NSW

Mar

itim

e

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m B

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adis

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Bay

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dy

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ch

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ch r

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iers

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ors

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int

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erve

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Bas

in

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lers

Bay

Treh

ame

Co

ve

We

st H

ead

Win

ner

err

emy

Fore

sho

re…

Wo

od

y P

oin

t

No

. of

spec

ies

Site

passerines raptors waterbirds

31

Mallards

White-faced heron

Little black cormorants

32

Waterbird habitat

Waterbirds were observed using nine main habitat types (Table 3, Figure 9, Figure 10):

Tidal sand flats

Man-made roosts e.g. boats, jetties

Rocky shorelines including trees and logs over water

Mangroves

Sandy beaches

Grassy parklands

Ponds

Shallow water

Open water e.g. channel

Use of these habitat types included behaviour such as foraging and roosting. No nesting was

observed during the surveys.

Habitat use

Table 3 Habitat use by waterbirds observed during surveys.

Habitat use Habitat type Species observed using habitat

Foraging

mangroves White-faced heron

Australian white ibis

open water Little pied cormorant

Pied cormorant

Silver gull

Pacific black duck

White-faced heron

Dusky moorhen

Australasian darter

shallow water Silver gull

Little pied cormorant

Royal spoonbill

White-faced heron

tidal sand flats Masked lapwing

Silver gull

Australian white ibis

White-faced heron

Striated heron

Eastern curlew

33

Chestnut teal

Australian wood duck

grass areas Purple swamphen

Dusky moorhen

Masked lapwing

Australian wood duck

Australian white ibis

White-faced heron

Silver gull

ponds Grey teal

Dusky moorhen

rocky shoreline White-faced heron

sandy beaches Masked lapwing

White-faced heron

Silver gull

tidal creek Dusky moorhen

Teal sp.

Roosting

logs/trees Little pied cormorant

Pied cormorant

White-bellied sea eagle

Striated heron

White-faced heron

boat Little black cormorant

Little pied cormorant

Pied cormorant

Silver gull

White-faced heron

Crested tern

grass Australian wood duck

Pacific black duck

Masked lapwing

posts in water White-faced heron

Little pied cormorant

Silver gull

jetty Pacific black duck

Little black cormorant

Little Pied cormorant

Pied cormorant

Silver gull

Masked lapwing

White-faced heron

34

Australian pelican

Australasian darter

Crested tern

mangroves Little pied cormorant

Little black cormorant

White-faced heron

Royal spoonbill

Australian white ibis

rocky shoreline Little pied cormorant

Little black cormorant

Pied cormorant

Great cormorant

Australasian darter

Australian pelican

Black-winged stilt

White-faced heron

Whistling kite

White-bellied sea eagle

Masked lapwing

Silver gull

sandy beaches Crested tern

Silver gull

Masked lapwing

Australian wood duck

Australian pelican

White-faced heron

Pacific black duck

35

Figure 9 Number of species observed foraging in using each habitat type.

Figure 10 Number of species observed roosting in each habitat type.

0

2

4

6

8

10

mangroves openwater

shallowwater

tidal sandflats

grassareas

ponds rockyshoreline

sandybeaches

tidal creek

No

. Sp

ecie

s

habitat types

0

2

4

6

8

10

12

14

16

18

20

rocky shoreline man-made roosts grass areas sandy beaches mangroves

No

. of

spe

cie

s

habitat type

36

Tidal sand flats

Man-made roosts

37

Rocky shorelines

Mangroves

38

Sandy beaches

Parklands, grassy areas

39

Figure 11 Dominant type of habitat used at each survey site. Note this is not a habitat classification of survey sites, as most sites have several habitat types present e.g. man-made roosts and sandy beaches.

!

_̂_̂

%

!

"

#

#

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!!

X

!

X"

X

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X

#

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%

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$

!

%

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%

!

X

$ $

$

%

"

"

9

8

7

6

5

4

32

1

57

56

55

54

5352

51

50

49

48

47

46

45

44

43

42

41

40

39

38

37

36

35

34

33

32

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

1514

13

12

1110

Scotland Is.

Careel Bay

McCarrs Ck

Pittwater

Barrenjoey

The Basin

¯

Legend

# grassy parklands

! man-made

! mangroves

$ open water

% rocky shoreline

_̂ sandy beach

" shallow water

X tidal flats

Pittwater Estuary

0 1 20.5 Km

40

Estuarine Habitats

With reference to the report 'Estuarine habitat mapping and geomorphic characterisation of

the lower Hawkesbury river and Pittwater estuaries’ Astles, K., West, G., Creese, R.G. 2010,

these surveys focused on the Pittwater Estuary sections of the Lower Hawkesbury Estuary

within Pittwater Local Government Area. Estuarine habitat mapping of the Lower

Hawkesbury Estuary identified eight unique estuarine habitats (Astles et al. 2010). These

included:

I. Seagrass

II. Mangroves

III. Saltmarsh

IV. Mudflats

V. Sandflats

VI. Rocky reef

VII. Foreshore habitat i.e. jetties, parks

VIII. Water column

Of these, we observed four of these habitat categories being used by waterbirds and

shorebirds; mudflats, foreshore habitats (man-made roosts, rocky shorelines, parklands)

mangroves, and sandflats. Mangroves can provide roosting sites and sheltered foraging

areas, while sandflats can provide areas for foraging (Figure 12). Foreshore habitats provide

areas for foraging and roosting.

Tidal sandflats were the habitat used for foraging by the greatest number of different

species (n=8; Figure 9). The availability of diverse foraging habitats is limited in the Pittwater

Estuary. There are relatively few areas of mangroves, saltmarsh, or sandflats, and there are

no areas of mudflats (Table 4; Figure 12).

Rocky shorelines (n=12), and other foreshore habitats such as jetties (n=10) provided

roosting habitat for the greatest number of species (Figure 10). This is a habitat type that is

relatively common in the Pittwater Estuary (Table 4,

Table 5, Figure 12).

41

Table 4 The availability of estuarine habitats used by waterbirds in the Pittwater Estuary, and as a proportion of total availability in the Lower Hawkesbury Estuary (LHE).

Estuarine Habitats Area/No. in Pittwater

Estuary

% of total available in LHE

Mangroves 17.48 ha 1.75

Saltmarsh 2.68 ha 0.92

Mudflats 0 0

Sandflats 88.154 ha 26.22

Jetties

Wharves

9

677

56.0

49.0

Recreational parks 15.725 km 53.42

Source: Astles et al. 2010.

The Hawkesbury-Nepean River system, of which Pittwater Estuary is a part of, has the

fewest estuarine areas of all coastal river systems (Creese et al. 2009). This is because the

Hawkesbury-Nepean River is effectively a drowned river valley (Creese et al. 2009) resulting

in very few tidal shallow water areas. As a result there are limited areas of suitable habitat

for waterbirds and shorebirds.

Key migratory waterbird sites in NSW include the Parramatta River, Botany Bay, Port

Hacking, and Hunter Estuary.

Table 5 Available roosting and foraging habitat in Pittwater Estuary (see Figure 12).

Habitat use Total area (ha) No. of patches Mean patch size (ha)

Roosting 17.48 184 0.09

Foraging 132.82 58 2.29

Man-made roosting habitat 686 structures

42

Figure 12 Waterbird foraging and roosting habitat in the Pittwater Estuary.

¯0 1 20.5 Km

Scotland Is.

Careel Bay

McCarrs Ck

Pittwater

Barrenjoey

The Basin

Legend

Man-made roosting habitat

Pittwater Estuary

Foraging habitat

Roosting/foraging habitat

43

Disturbance

Disturbance was classified into six broad categories (Figure 13):

1) Human activity, for example swimming, golf, walking, camping, and picnicking.

2) Dogs on leash

3) Dogs off leash

4) Vehicles

5) Other wildlife

6) Construction noise

Sixty one per cent of survey sites (n=34) recorded disturbance to waterbirds (Figure 14).

Human activities were the greatest cause of disturbance to waterbirds (n=44) while dogs off

leash were the second greatest (n=40) cause of disturbance and potentially more of a threat

to waterbirds and dogs were often observed chasing birds (Figure 13). The disturbance to

waterbirds as a result of human activities, including dog walking in Pittwater is not

surprising given the large number of foreshore parks. However the recorded instances of

disturbance caused by dogs off leash were much higher than disturbance caused by dogs on

leash (Figure 13).

Figure 13 Frequency of waterbird disturbance types recorded in Pittwater Estuary.

0

5

10

15

20

25

30

35

40

45

50

human activity vehicle dogs off leash constructionnoise

dogs on leash other wildlife

Co

un

t o

f d

istu

rban

ce r

eco

rded

Disturbance category

44

Figure 14 Counts of different disturbance types at survey sites.

0

1

2

3

4

5

6

7

8

9

Ava

lon

Sai

ling

Clu

b

Bar

ren

joey

He

ad -

oce

an b

each

Bar

ren

joey

He

ad -

Pit

twat

er

be

ach

Bay

view

bo

at r

amp

Bay

view

ch

ann

el

Bay

view

Go

lf C

ou

rse

Bay

view

Par

k

Bay

view

Sp

it

Bay

view

Yac

ht

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ing

Ass

oci

atio

n

Bro

wn

s B

ay

Car

eel

Bay

Car

eel

Bay

- e

nd

of

Ge

org

e St

Car

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no

rth

Ch

urc

h P

oin

t

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lle B

each

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rs R

etre

at

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ren

ce P

ark

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at M

acke

rel B

eac

h

Litt

le L

ove

tt B

ay

Luci

nd

a P

ark

May

ban

ke C

ove

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arrs

Cre

ek

Res

erve

Mo

rnin

g B

ay

Pal

m B

each

go

lfco

urs

e

Re

fuge

Co

ve

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solu

te B

each

Ro

bo

tmo

wn

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ss

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dy

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ch

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tlan

d Is

lan

d -

no

rth

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tlan

d Is

lan

d -

so

uth

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per

man

bea

ch r

ese

rve

Tayl

ors

Po

int

Res

erve

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lers

Bay

Win

ner

err

emy

Fore

sho

re R

ese

rve

Co

un

t o

f d

istu

rban

ce t

ype

Survey site

other wildlife dogs on leash construction noise dogs off leash vehicle human activity

45

Discussion

The sites in Pittwater Estuary with the greatest species diversity of waterbirds were Careel

Bay (n=13), Bayview Golf Course (n=12) and Barrenjoey Head/Beach (n=10). Species found

at Careel Bay were predominantly wading species such as herons, ibis, spoonbills and

lapwings. Bayview Gold Course was dominated by herbivorous species such as ducks,

moorhens and swamphens. Barrenjoey Head/Beach was dominated by pisciverous species

such as cormorants and pelicans. Bayview Gold Course recorded the highest single species

abundance on two occasions of Australian Wood Duck (n=79 on the 27/4/2012 and n=74 on

the 31/05/2012).

These surveys recorded relatively low numbers of waterbird abundance. However these are

consistent with surveys conducted on other parts of the Lower Hawkesbury Estuary (Brandis

and Watson, 2011; Recher 2012). The cumulative species curve (Figure 7) which illustrates

the detection of new species during each subsequent survey only began to flatten at survey

10 out of a total of 11 surveys. This may suggest that further surveys could have detected

additional species, however the diversity of species recorded during these limited surveys is

consistent with previous studies. These surveys recorded 30 out of a total 59 species

historically recorded for the Pittwater Estuary. It should be noted that some of the species

listed here have been observed only once, e.g. the Australasian bittern, and that some

survey records span >40 years e.g. Atlas and H. Recher data.

Climate change and sea level rise

Climate change is projected to cause significant alterations to aquatic processes, including

food web structures, population dynamics, biodiversity, and primary and secondary

production. It will also affect the range, distribution and habitat quality/quantity of aquatic

flora and fauna (Wrona et al. 2006).

Direct effects of sea level rise will result in increased water depths, changes in tidal variation

(both mean tide level and tidal range), altered water movement patterns, and increased

seawater intrusion into estuaries and rivers (Short and Neckles 1999). These changes will

result in a redistribution of habitats in affected areas including a potential loss of intertidal

habitats for waterbirds and shorebirds (Galbraith et al. 2002). The ability of habitats to be

46

redistributed in the Pittwater Estuary is influenced by a significant number of variables.

These include but are not limited to: the position of the habitat patch in the Estuary, the

surrounding topography, the extent of surrounding land development, changes in the

movements of sediment, changes in tidal reach, the response of aquatic and terrestrial

vegetation and changes in the food web structure.

Galbraith et al. (2002) report that the most severe losses of habitat are likely to occur at

sites where the coastline is unable to move inland because of steep topography or seawalls

and that the effects of sea level rise may be exacerbated by additional anthropogenic

factors. This is particularly applicable to the Pittwater Estuary where the western side is

bounded by steep sided ridges while the eastern side is bounded by residential

development. There are limited options for the natural relocation of suitable waterbird

habitats.

The Cardno report (2010) examined the impact of sea level changes on foreshore flood

planning levels for Pittwater LGA. They calculated foreshore flood planning levels for five

general foreshore types; grassed and sandy gently sloping foreshores, natural rocky

foreshores, vertical sea walls and mangroves. The report found that that the predominant

foreshore type for the developed parts of Pittwater foreshore is sea walls of varying heights

(typically 1-1.5 m high). Natural rocky shoreline and natural slope (grassed and/or sandy)

were the other typical foreshore types observed. Mangroves were also observed in Careel

Bay.

This report found that the habitats used most frequently for foraging by waterbirds and

shorebirds were tidal flats and grassy areas (Figure 9). These are areas with typically low

elevations and may be most impacted by sea level rise (Table 6,Figure 15). Depending upon

their position within the estuary these habitats may either move inland if possible, or

disappear from that location. The habitats used most frequently for roosting were rocky

shorelines and man-made structures such as jetties and wharves (Figure 10). These habitat

types may not be as impacted by sea level rise as those areas used for foraging.

47

Table 6 Area of waterbird habitat most at risk from sea-level rise.

Waterbird habitat type Total area (ha)

Foraging 132.82

Roosting 17.48

Total area of habitat threatened 150.30

Projected effects on migratory shorebirds include altered migration routes and timing; a

possible increase in the incidence of mortality and decreased growth and productivity from

disease and/or parasites; and, probable changes in habitat suitability and timing of

availability (Wrona 2006). These surveys recorded only one species of migratory shorebird,

the Eastern Curlew, and only observed three individuals in the Careel Bay area. The impact

on Eastern Curlew using the Pittwater Estuary is difficult to determine as abundance was

very low. It may be that these individuals were not residents but were still moving to more

significant shorebird sites such as Botany Bay. Further surveys may record additional

migratory species, however the results of these surveys were consistent with those from the

Lower Hawkesbury Estuary (Brandis et al. 2011).

48

Figure 15 Waterbird habitat areas likely to be impacted by sea level rise.

¯0 1 20.5 Km

Scotland Is.

Careel Bay

McCarrs Ck

Pittwater

Barrenjoey

The Basin

Legend

Waterbird habitat threatened by sea level rise

Pittwater Estuary

49

Table 7 Comparison of species records between UNSW 2012 surveys and others.

All waterbird species recorded UNSW 2012

ATLAS 1970-2012

H. Recher 1967-2011

Smith & Smith 1997

Smith & Smith 2001

Australasian bitterna

x Australasian darter X

x

Australasian gannet X

x Australian pelican X x x x x

Australian white ibis X

x x x

Australian wood duck X Azure kingfisher X

x x Bar-tailed godwit

x x

Black swan

x

x

Black-winged stilt X Brown goshawk

x

Buff banded rail

x Bush-stone curlew

x

x

Cattle egretb

x x

Chestnut teal X

x Collared sparrowhawk

x

Common sandpiper

x

Crested tern X x x x x

Domestic goose X

x

Dusky moorhen X x Eastern Curlew X x x x x

Fluttering Shearwater

x Great cormorant X

x

x

Great egret X

x x Grey teal X

x

Grey-tailed tattler

x

Little black cormorant X

x x x Little egret

x x

Little fairy penguin

x x Little pied cormorant x x x x x

Mangrove gerygone

x

x Mangrove warbler

x

Masked lapwing x x x x Nankeen kestrel

x

Northern mallard x

x x

Pacific black duck x x x x x Parasitic Jaeger

x

Peregrine falcon

x Pied cormorant x x x

x

Pied oyster catcher

x

50

Pomarine Jaegerc

x

Purple swamphen x Red-capped dotteral

x

Royal spoonbill x x

x Sacred kingfisher x

x x

Silver gull x

x x x Southern stone plover

x

Straw-necked Ibis

x

Striated (Mangrove) heron x x x x x

Wedge-tailed Eagle

x Whimbrel

x x x x

Whistling kite x x x x x

White-bellied sea eagle x x x x White-faced heron x x x x x

White-fronted ternd

x

White-headed stilt x a Single record from 1970; no observations since.

b cannot recall any sightings in at least 5 years or since 2006, and no records in the books; present on Danger Is in 2011 – H. Recher (Appendix 1).

c Pomarine jaegar and Arctic jaegar are difficult species to differentiate; it may be that there has only been one species of Jaegar observed. Both UNSW and H. Recher observations were of single birds.

d No recent records of white-fronted terns. Numbers of Crested Tern are now 50% of 20-30 years ago. – H. Recher (Appendix 1).

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Key findings

In summary, the key finding of this report are:

1) There were low numbers of migratory shorebirds observed in the Pittwater Estuary

during January-June 2012 but that these findings were not unusual or unexpected

when compared with other datasets.

2) Due to the geomorphology of the Hawkesbury River, including the Pittwater Estuary

there are very few large tidal shallow water estuary areas to provide suitable

migratory shorebird habitat. Within the Pittwater Estuary the largest shallow water

tidal areas include Careel Bay and the Maybanke Cove/Winnererremy Foreshore

Reserve areas, however when compared to other areas such as Botany Bay these

areas are relatively small. The limited availability of suitable roosting and foraging

habitat in the Pittwater Estuary is consistent with the low numbers of migratory

shorebirds observed during these surveys.

Recommendations

The recommendations from this report include the following points:

1) We would recommend a longer term survey be carried out, for at least a 12 month

period. A longer term survey will identify seasonal changes in species diversity and

abundance and may identify additional habitat areas. This could potentially be done

using council staff and/or local interest groups.

2) We would recommend a review of dog off leash areas with regards to proximity to

waterbird habitats.

3) With regards to Council’s planning for rising sea levels it may be appropriate for

Council to identify areas where waterbird habitat may shift to as sea levels rise and

existing habitat becomes unsuitable.

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References

Astles, K., West, G., Creese, R.G. (2010) Estuarine habitat mapping and geomorphic

characterisation of the lower Hawkesbury river and Pittwater estuaries. Industry &

Investment NSW, Port Stephens Fisheries Institute.

Brandis, K and Watson, H. (2011) Estuarine Wetland and Migratory Bird Survey and Priority

Habitat Mapping. Final report to Hornsby Shire Council. Australian Wetlands and Rivers

Centre, University of New South Wales.

Coughlan, R. (2008). Pittwater LGA bird survey 2006-2007. Report to Pittwater Council.

Creese, R.G., Glasby, T.M., West, G., Gallen, C. (2009) Mapping the habitats of NSW

estuaries. Report to the Hunter Central Rivers Catchment Managment Authority September

2009. Industry & Investment NSW, Port Stephens Fisheries Institute.

Galbraith, H., Jones, R., Park, R., Clough, J., Herrod-Julius, S., Harrington, B., Page, G. (2002).

Global climate change and sea level rise: potential losses of intertidal habitat for shorebirds.

Waterbirds 25, 173-183.

Nebel, S., J. Porter, et al. (2008) Long-term trends of shorebird populations in eastern

Australia and impacts of freshwater extraction. Biological Conservation 141: 971-980

Pittwater Council and Ecotone Ecological Consultants (2010). Native fauna management

plan for the Pittwater local government area.

Recher, H. (pers. comm. 2012) Table of Aquatic Birds for the Lower Hawkesbury River,

Patonga Creek, Broken Bay, Pittwater, and Brisbane Water, 1967-2011.

Short, F. T., Neckles, H.A. (1999). The effects of global climate change on seagrasses. Aquatic

Botany 63, 169-196.

Smith, P. and J. Smith (1997). Bird habitat study of Careel Bay. Report to Pittwater Council.

Smith, P. and J. Smith (2001). Waterbird survey of Careel Bay. Report to Pittwater Council.

Wrona, F. J., Prowse, T.D., Reist, J.D., Hobbie, J.E., Levesque, L.M.J., Vincent, W.F. (2006).

Climate change effects on aquatic biota, ecosystem structure and function. AMBIO: A

journal of the Human Environment 35, 359-369.

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Appendix 1: Table of Aquatic Birds for the Lower Hawkesbury River, Patonga

Creek, Broken Bay, Pittwater, and Brisbane Water, 1967-2011

Harry F. Recher

Senior Fellow, The Australian Museum, College St., Sydney, NSW

LHR (Lower Hawkesbury River from Road Bridge to Juno Pt. and Iron Pots), PC (Patonga

Creek), BB (Broken Bay from Juno to Lion Island and Barrenjoey and immediate ocean), PITT

(Pittwater inside West Head and Barrenjoey), BW (Brisbane Water)

LOCATION No’s Year

SPECIES LHR PC BB PITT BW

Little Penguin X X X 0’S 67-11

Fluttering Shearwater X 000’S

Wedge-tailed Shearwater X 0’S 67-11

Sooty Shearwater X 0’S 67-11

Short-tailed Shearwater X X 000’S

Big Black Cormorant X X X X X 0’S 67-11

Little Black Cormorant X X X X X 0’S 67-11

Big Pied Cormorant X X X X X <10 67-11

Little Pied Cormorant X X X X X 0’S 67-11

Anhinga (Darter) X X X X X 1-10 67-11

Australian Gannet X X X 1-10 67-11

Australian Pelican X X X X X 0’S 67-11

Buff-banded (Banded) Landrail X 1 Mid-

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Mar'2012 DIs

White-fronted Tern** X X X 1-10

Crested Tern X X X X X 10-30 67-11

Silver Gull X X X X X 00’S 67-11

Parasitic Jaeger X X X X 1-2 67-11

Pomarine Jaeger X X X X 1-2 67-11

Spur-winged Plover (Masked

lapwing)

X X X 1-10 67-11

Red-capped Dotteral X 1-10

Eastern Curlew X X 1-10 67-11

Whimbrel X X 1-10 67-11

Bar-tailed Godwit X X 1-10 67-11

Grey-tailed Tattler X X 1 DIs

Common Sandpiper X X 1 DIs

Sharp-tailed Sandpiper X* 1 2008 DIs

White-headed Stilt X X 10-20 irreg.

Avocet X 2 Oct'11

Pied Oystercatcher X X 2,3 DIs

Oct’ 11; 3-5

birds

2 Pied Oystercatcher Dangar Island

on 17-18 June 2012

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Southern Stone Plover X X 2-4 Careel Bay &

Riley's Is.

White Ibis X X X X X 0’S irreg. 67-11

Straw-necked Ibis X X X X X 0’S irreg. 67-11

Black-billed Spoonbill X X 1-2 2 on DIs,

6.6.12

White-faced Heron X X X X X 0’S 67-11

Little Egret X X X X <10 irreg. 67-11

Great Egret X X X X <10 irreg. 67-11; 1

on D Is

13.5.12

Nankeen Night Heron X 10

Mangrove Heron X X X X X 20-25 67-12

Cattle Egret*** X 5-25 irreg. ?. but

seen 2011 &

2012 at DIs

Black Swan X X X <10 irreg

Wood Duck X 20-30 67-11

Australian Black Duck X X X X X 10-20 67-11

Chestnut Teal X X X X X 20-20 67-11

Grey Teal X X X X X 10-20 67-11

Mallard & hybrids, incl. Muscovy X <10 67-11

White-breasted Sea Eagle X X X X X 20-30 67-11

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Whistling Kite X X X X X 20-30 67-11

Azure Kingfisher X X X <10 67-11

NOTES:

1. 67-11 indicates regular occurrence with birds being recorded annually, if not every month

2. irreg. are birds that I see every few years or even more often, but definitely not every year. Numbers can be highly variable.

3. other birds are infrequent or, at least, seldom seen. Numbers are usually in 1s and 2s at most.

4. * one bird 2008 on Dangar Island

5. numbers are a gauge only and refer to numbers when the birds are present

6. ** I have no recent records of white-fronted terns. Numbers of Crested Tern are now 50% of 20-30 years ago.

7. Most species seem as common today as in 1970s. There are more pelicans, but cormorant numbers are even. Little Blacks in Lower Hawkesbury fluctuate in abundance from <10 to 50+. Often roost on DIs

8. Duck numbers, except for Wood Duck, are lower now than in 1970s abd 80s, even the early 90s.

9. *** cannot recall any sightings in at least 5 years or since 2006, and no records in the books; present on DIs in 2011

NOTES

1. The flats and shallows around Dangar Island have never been good for migratory waders. Curlew, whimbrel, and Bar-tailed Godwit are regular (annual) transients, but generally the water on the flats is too deep for small waders. Spur-winged Plover and White-faced Heron use the flats, Dangar Beach, and Dangar foreshores throughout year. Numbers have been consistent since 1967, with 2-6 plovers (6 in 2011/12; good season for reproduction) and 2-6 herons. Herons are pair territorial, but out of nesting season there can be groups of up to 8 birds along lower river and BB. The other migratory waders may occur more frequently than I indicate, but they rarely stay more than a few days and so are probably missed more often than not. Main loafing area on lower river is the rocky spit at east end of Dangar (Mullet) Beach. Dogs are a problem on the spit and along the beach.

2. Mangrove Warbler. We did not record warblers during our surveys of mangroves in The Gut (Brooklyn) in the '70s (I can extract exact dates) nor at Careel Bay in the '70s. I recall seeing warblers up river near Spencer in the '70s and thinking they were first records. I do not see or hear warblers in Patonga Creek, but have not done a thorough search in recent

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years. Same for Pumpkin Creek which I visit ~ once/year, but missed 2011. I have never checked the mangroves in Porto Bay and have not paid much attention to those in Brooklyn since the '70s when we were fighting to stop the Council and Lands Dept. from clearing them.