Marine and Freshwater Resources Institute Report No. 28

SEAGRASS MAPPING OF VICTORIA’S

MINOR INLETS

Sean Blake, Ralph Roob and Elizabeth Patterson

July 2000 Marine and Freshwater Resources Institute

Report No. 28

SEAGRASS MAPPING OF VICTORIA’S

MINOR INLETS

Sean Blake, Ralph Roob and Elizabeth Patterson

July 2000

Marine and Freshwater Resources Institute PO Box 114 Queenscliff 3225 Copyright © The State of Victoria, Department of Natural Resources and Environment, 2000

This work is copyright. Apart from any use under the Copyright Act 1968, no part may be reproduced by any process without written permission.

ISSN: 1328-5548

ISBN: 0 7311 4724 3

Copies available from: Librarian Marine and Freshwater Resources Institute PO Box 114 Queenscliff VIC 3225

Phone: (03) 5258 0259 Fax: (03) 5258 0270 Email: [email protected]

Preferred way to cite this publication: Blake, S., Roob, R. and Patterson, E. (2000) Seagrass Mapping of Victoria’s Minor Inlets. Marine and Freshwater Resources Institute Report No. 28. July 2000 (Marine and Freshwater Resources Institute: Queenscliff).

General disclaimer: This publication may be of assistance to you but the State of Victoria and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication. Seagrass Mapping of Victoria’s Minor Inlets

CONTENTS

List of Figures...... ii

List of Tables...... ii

List of Historical Photographs...... ii

List of Appendices...... iii

1. INTRODUCTION...... 1

1.1 Study Sites ...... 2 1.1.1 Anderson Inlet...... 3 1.1.2 Shallow Inlet ...... 3 1.1.3 Sydenham Inlet...... 3 1.1.4 Tamboon Inlet ...... 4 1.1.5 Wingan Inlet...... 4 1.1.6 Mallacoota Inlet...... 4

2. SPATIAL DISTRIBUTION AND DENSITY OF SEAGRASS IN THE MINOR INLETS...... 6

2.1 Survey Methodology...... 6 2.1.1 Remote Sensing of the Estuarine Environment...... 6 2.1.2 Photography Specifications...... 6 2.1.3 Aerial Photography Interpretation...... 6 2.1.4 Field Verification Process ...... 6 2.1.5 Field Classifications...... 7 2.2 Results ...... 10 2.2.1. Anderson Inlet...... 10 2.2.2. Shallow Inlet ...... 11 2.2.3 Sydenham Inlet...... 12 2.2.4 Tamboon Inlet ...... 13 2.2.5 Wingan Inlet...... 14 2.2.6 Mallacoota Inlet...... 15 2.3 Discussion...... 18

3. ASSESSMENT OF HISTORIC SEAGRASS CHANGES IN THE MINOR INLETS ...... 27

3.1 Background...... 27 3.2 Previous Studies...... 27 3.2.1 Anderson Inlet...... 28 3.2.2 Shallow Inlet ...... 28 3.2.3 Sydenham Inlet...... 29 3.2.4 Tamboon Inlet ...... 29

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3.2.5 Wingan Inlet...... 29 3.2.6 Mallacoota Inlet...... 29 3.3 Selection of Historic Aerial Photography and Study Sites...... 29 3.4 Interpretation of Historic Aerial Photography...... 30 3.5 Observations from Historic Photography...... 31 3.5.1 Shallow Inlet ...... 31 3.5.2 Sydenham Inlet...... 32 3.5.3 Mallacoota Inlet...... 33 3.6 Results ...... 48 3.7 Discussion...... 49

ACKNOWLEDGMENTS...... 50

REFERENCES...... 50

LIST OF FIGURES

Figure 1.1 Minor inlets location map ...... 2 Figure 2.1 Seagrasses of the Minor Inlets ...... 9 Figure 2.2a-g Maps of seagrass distribution in the minor inlets...... 20-26 Figure 2.3 Bar graph of total seagrass areas against the total area of each inlet ..17 Figure 2.4a-f Subtidal vegetation area summaries (pie charts) ...... 10-15 Figure 3.1 Location of study site, Shallow Inlet...... 31 Figure 3.2 Location of Study Sites 1 and 2, Sydenham Inlet ...... 32 Figure 3.3 Location of Study Site, Mallacoota Inlet...... 34

LIST OF TABLES

Table 2.1 Classification categories recorded during the field surveys ...... 8 Table 2.2 Summary Area Statement of Seagrass Categories Recorded in the Minor Inlets...... 16 Table 3.1 Comparison of seagrass areas 1989 and 1999...... 28 Table 3.2 Aerial photographs presented for the study sites...... 30 Table 3.3 Summary of changes, peaks and lows in seagrass at the study sites ...49

LIST OF HISTORICAL AERIAL PHOTOGRAPHS

Photo 3.1a Shallow Inlet Site, 28 November 1972 ( approx scale 1:10,000). Photo 3.1b Shallow Inlet Site, 13 January 1981 ( approx scale 1:10,000). Photo 3.1c Shallow Inlet Site, 7 February 1987( approx scale 1:10,000). Photo 3.1d Shallow Inlet Site, 3 January 1991 ( approx scale 1:10,000). Photo 3.1e Shallow Inlet Site, 18 April 1993 ( approx scale 1:10,000). Photo 3.1f Shallow Inlet Site, 25 April 1999( approx scale 1:10,000).

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Photo 3.2a Sydenham Inlet Site 1, 11 March 1973 (approx scale 1:10,000). Photo 3.2b Sydenham Inlet Site 1, 8 January 1977 (approx scale 1:10,000). Photo 3.2c Sydenham Inlet Site 1, 3 March 1982 (approx scale 1:10,000). Photo 3.2d Sydenham Inlet Site 1, 4 November 1986 (approx scale 1:10,000). Photo 3.2e Sydenham Inlet Site 1, 30 January 1987 (approx scale 1:10,000). Photo 3.2f Sydenham Inlet Site 1, 17 March 1990 (approx scale 1:10,000). Photo 3.2g Sydenham Inlet Site 1, 26 April 1999 (approx scale 1:10,000).

Photo 3.2h Sydenham Inlet Site 2, 15 January 1986 (approx scale 1:10,000). Photo 3.2i Sydenham Inlet Site 2, 30 January 1987 (approx scale 1:10,000). Photo 3.2j Sydenham Inlet Site 2, 17 March 1990 (approx scale 1:10,000). Photo 3.2k Sydenham Inlet Site 2, 26 April 1999 (approx scale 1:10,000).

Photo 3.3a Mallacoota Inlet Site, 7 April 1969 (approx scale 1:10,000). Photo 3.3b Mallacoota Inlet Site, 10 March 1973 (approx scale 1:10,000). Photo 3.3c Mallacoota Inlet Site, 8 October 1977 (approx scale 1:10,000). Photo 3.3d Mallacoota Inlet Site, 4 November 1986 (approx scale 1:10,000). Photo 3.3e Mallacoota Inlet Site, 8 March 1990 (approx scale 1:10,000). Photo 3.3f Mallacoota Inlet Site, 1994 (approx scale 1:10,000). Photo 3.3g Mallacoota Inlet Site, 26 April 1999 (approx scale 1:10,000).

LIST OF APPENDICES

Appendix 1. Ground-truthing field data sheets...... A1 Appendix 2. Summary table of ground-truthing sample points recorded in the minor inlets...... A15 Appendix 3. Seagrass Layer Documentation...... A17 Appendix 4. Minor Inlets Historical Aerial Photography ...... A24

Important Note on Seagrass Species Definition

The two species of Zosteraceae observed in Western Port; Heterozostera tasmanica and Zostera muelleri, cannot be differentiated by the remote sensing techniques employed in this study and have been grouped into a single generic category of “Zostera”. As a result, all references to “Zostera” in this report include both Heterozostera tasmanica and Zostera muelleri.

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1. INTRODUCTION

The Department of Natural Resources and Environment (NRE) is undertaking a state-wide program to map and characterise the distribution of seagrass communities throughout Victoria. Previous seagrass studies have been conducted by the Marine and Freshwater Resources Institute (MAFRI) for the Gippsland Lakes (Roob & Ball, 1997), Corner Inlet and Nooramunga (Roob et al., 1998) and Western Port (Blake et al., 2000). A seagrass mapping program for Port Phillip Bay is being undertaken in 2000.

The work conducted in Victoria’s bays and inlets will provide ecological information towards an improved understanding of seagrass distribution and diversity, its role in commercial and recreational fisheries as well as baseline data for future environmental monitoring. The results of this study will also be integrated with The Environmental Inventory of Victoria’s Marine Ecosystems, a multi-stage project to provide information on the diversity of marine ecosystems at various spatial scales (Ferns and Hough, 1999).

Seagrasses are aquatic angiosperms. Their internal structures, pollination mechanisms and fruit dispersal tactics all show particular adaptations to a completely aquatic existence. Seagrasses have extensive horizontal underground stems (rhizomes) and strong roots that anchor the plant to the soft bottom. The roots absorb nutrients, but do not take up water. To cope with living in oxygen-poor mud, seagrasses have evolved air canals that carry oxygen from the leaves to the buried rhizomes and roots. Erect branches and leaves grow off the buried stem. The leaves have a thin skin that allows efficient nutrient and gas uptake from the water (Lloyd, 1997).

Typically, seagrass meadows are found in water depths of 2-12 metres, where sunlight intensity is greatest and therefore seagrass growth is highest (Lloyd, 1997). The photosynthetic activity of seagrass beds is so great it can cause significant changes in oxygen, carbon dioxide and acidity levels of the surrounding water (Lloyd, 1997).

Seagrasses are colonisers of mud, silt and sand, using their extensive rhizome systems to anchor themselves and consequently stabilising the sediments. The leaves also retard currents and increase sedimentation of material around the plants. Seagrass is important for water quality helping to maintain low concentrations of suspended solids, silicate and phosphorus.

Seagrass is an ecologically significant marine habitat being both highly productive and providing food and shelter for many organisms. Small animals are able to shelter in the seagrass leaves, receiving protection from predators and from excessive sunlight or temporal changes in salinity and temperature (Hastings, 1995). Seagrass meadows provide food for benthic fauna and scavenger communities living in the mudflats, these in turn provide food for fish, crustaceans, birds and waterfowl. Many organisms receive nutrients from seagrass detritus, either directly or indirectly. Some animals feed directly on the seagrass, such as Black Swans, while others graze on the leaf epiphytes or on the seagrass detritus.

Seagrass meadows provide ideal habitats for fish and especially as a nursery for juvenile fish. Jenkins et al (1997) compared fish assemblages of seagrass habitats with fish assemblages of unvegetated habitats in different areas of Victoria. It was found that diversity was higher in seagrass meadows than in unvegetated areas. The larval stages of

Marine and Freshwater Resources Institute – Page 1 Seagrass Mapping of Victoria’s Minor Inlets some fish species such as Blue Rock Whiting, Six-spine Leather Jacket and Rough Leather Jacket settled directly on deeper, subtidal Heterozostera tasmanica beds, while adult Rock Flathead and juvenile Luderick also favoured seagrass sites. Flounder, while favouring unvegetated habitats, are thought to benefit from organic enrichment of sediments by seagrass debris due to increased food production (Shaw & Jenkins 1992, and Jenkins et al 1993, cited in Jenkins et al, 1997). In general, biomass and abundance in fish were greater in subtidal seagrass habitats than in unvegetated, subtidal habitats.

1.1. Study Sites

The sites described as the minor inlets and addressed by this study are listed below and are shown in Figure 1.1. These inlets were chosen to complete the baseline mapping of seagrass habitats in Victoria. As stated previously, seagrass distribution in the Gippsland Lakes, Western Port and Corner Inlet-Nooramunga has already been mapped in the period since 1997 and Port Phillip Bay is being mapped during 2000. The minor inlets thus represented the remaining known seagrass habitats in Victoria.

· Anderson Inlet · Tamboon Inlet · Shallow Inlet · Wingan Inlet · Sydenham Inlet · Mallacoota Inlet

Mallacoota Inlet

Tamboon Inlet Wingan Inlet VICTO R IA Sydenham Inlet

We stern P ort Ba y Anderson Inlet

Shallow Inlet

Corner Inle t & Noor amuga

Wil sons P rom BASS STR AIT

N

50 0 50 100 Kilo meters W E

S

Figure 1.1 Minor inlets location map.

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1.1.1 Anderson Inlet

Anderson Inlet is located 120 km south east of Melbourne on the South Gippsland coast (Fig. 1.1). The inlet forms an estuary of the Tarwin River, one of the largest and most dynamic estuarine systems in Victoria, with a catchment area of 1,670 km2 (Saenger and Bucher, 1989).

The inlet features approximately 8.8 km2 of intertidal mud and sand flats. A sand bar across the main entrance influences the dynamics of the inlet. Interactions between tidal flow, river discharge, tidal circulation and wave action determine the position and shape of the entrance. Fluctuations in flow from the Tarwin River also play an important role in influencing the characteristics of the inlet. The flow characteristics can determine the amount of nutrients entering the area, affecting the water quality and ecosystems of the inlet ( DCNR, 1994).

Anderson Inlet and the nearby township of Inverloch are popular destinations for Victorian visitors. The inlet and the foreshore area around it have a high conservation value with a wide variety of flora and fauna, including seagrass and internationally significant migratory wading birds (DCNR, 1994).

1.1.2 Shallow Inlet

Shallow Inlet is located north west of Wilson’s Promontory, about 180 km south east of Melbourne (Fig. 1.1). The inlet features a mixture of sand beaches, sand dunes, mud flats, seagrass beds and wetlands with extensive intertidal areas.

In 1986 the Shallow Inlet Marine and Coastal Park was established in recognition of its high value as a wildlife habitat, particularly for migratory waders and shore birds, including the Eastern Curlew, Red-necked Stint, Curlew Sandpiper, Pelicans, Swans, Oyster-catchers, Bar-tailed Godwit and Red Knot (DCFL, 1990).

1.1.3 Sydenham Inlet

Sydenham Inlet, located at the mouth of the Bemm River, is a large estuarine lagoon (approximately 10 km2) with a catchment area of 110 km2 and is intermittently sealed off from the sea by a sandy barrier (Fig. 1.1). Several geomorphological features associated with the estuary are of state significance, notably the active and abandoned river deltas and the extensive wetlands and tidal channels associated with Swan Lake and Mud Lake. The inlet is part of Cape Conran Coastal Park.

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1.1.4 Tamboon Inlet

Tamboon Inlet is a small estuarine lagoon at the mouth of the Cann River in eastern Victoria (Fig. 1.1). The main access to the inlet is by small boat, from Furnell Landing, which is 22 km south of Cann River township, 433 km east of Melbourne on the Princes Highway (Winstanley, 1985). The inlet is separated from the sea by a sand barrier and bounded by vegetated sand dunes, brackish marsh, granite slopes and fringing rock platforms. Tamboon Inlet is also part of the Croajingolong National Park.

Tamboon Inlet consists of two basins separated by a sand bar and a long tapering spit which is periodically broached by rising water levels in the inlet (Winstanley, 1985). The northern basin has a smooth floor, with fine sediment, sloping gradually to a depth of 8 m. The southern basin contains coarser sediments and slopes more steeply to a depth of 12m. A 2-3m deep channel runs down the eastern side of the inlet from the Cann River mouth to the inlet mouth where it attains a depth of 8 m (Winstanley, 1985).

Salinity in the inlet ranges from 14 to 25 ppt depending on levels of catchment run-off and the inlet is strongly stratified with pockets of saline water trapped in the two basins. When the entrance is closed the river can discharge a freshwater plume up to 3 m deep, which overlies the deeper more saline water and results in an overall depth increase in the inlet of over 1.5 m (Winstanley, 1985).

1.1.5 Wingan Inlet

Wingan Inlet is a small estuary in the Croajingolong National Park, 50 km south east of Cann River township and 450 km east of Melbourne on the Princes Highway (Fig. 1.1). Wingan Inlet has a catchment area of about 435 km2.

The inlet is one of the few remaining estuaries in south east Australia with an almost completely undisturbed catchment and the water chemistry is probably in a natural condition.

1.1.6 Mallacoota Inlet

Mallacoota Inlet is the eastern most estuary in Victoria, located about 550 km east of Melbourne and 5-10 km from the Victoria-New South Wales border (Fig. 1.1). The catchment area is 1525 km2.

The main access to the inlet is by road from Genoa, via the Princes Highway, to the township of Mallacoota. Numerous bush tracks also lead to the inlet and small boats (up to 6 m) can navigate around the inlet and up the Genoa and Wallagaraugh Rivers. In calm sea conditions, vessels up to 10 m can enter the inlet from Bass Strait across a shallow, sandy entrance bar (MacDonald et al., 1994).

Accelerated sediment deposition from catchment and riverbank erosion has been identified as a serious problem in the lower reachers of the Wallagaraugh and Genoa Rivers and parts of the Top Lake. Continued alterations to the catchment and watercourses draining into Mallacoota Inlet from these types of activities may increase the rate of sediment transport

Marine and Freshwater Resources Institute – Page 4 Seagrass Mapping of Victoria’s Minor Inlets to the inlet. Sediment loading has the potential to affect fish production, or availability; by degrading spawning and nursery habitats; altering flow regimes and salinity profiles; reducing water quality (eg increased turbidity); and disrupting food chains (Hall & MacDonald, 1986, in: MacDonald et al., 1994).

The inlet is surrounded by the Croajingolong National Park, State Forest, and private land. The main commercial activities in the Mallacoota area include fishing, tourism, grazing, timber production and agriculture (MacDonald et al., 1994).

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2. SPATIAL DISTRIBUTION AND DENSITY OF SEAGRASS IN THE MINOR INLETS

This section details the spatial extent, species distribution and density of seagrass meadows in the minor inlets through the use of remote sensing techniques and field verification.

2.1 Survey Methodology

2.1.1 Remote Sensing of the Estuarine Environment

Aerial photography was selected as the most effective method for remotely sensing the spatial extent of seagrass meadows at the pre-determined scale of 1:10,000. In order to accurately quantify the spatial extent of seagrass it is essential that the photography be taken when optimum conditions exist to maximise light penetration through the water column. Cloud free days and after a period of calm weather with low rainfall were the primary considerations. Other considerations that reduce water clarity include the occurrence of algal blooms and freshwater input from the numerous rivers that discharge into the study areas.

Aerial photography was flown between 19-26th April, 1999 with a state of the art Zeiss LMK 2000 aerial survey camera. This camera uses a 230mm x 230mm negative format. It employs a gyro-stabilised platform and forward motion compensation thereby incorporating full image compensation. For any shot taken, the camera can identify film type/speed, available light, airspeed over ground, height above ground and calculate how far the image will move during exposure. This is then compensated for by the film speed transport mechanism moving backwards at the appropriate speed.

2.1.2 Photography Specifications

The aerial survey camera system described above is capable of producing exceptionally clear photographs enabling the photography to be flown at the scale of 1:20,000 and then reproduced at 1:10,000 for final interpretation, without compromising detail. As a result, a map scale of 1:10,000 was adopted to display the extent of seagrass meadows within the minor inlets.

2.1.3 Aerial Photography Interpretation

Colour positives of the aerial photography were contact printed as double size, full frame enlargements. The boundaries of the seagrass meadows were interpreted from these and plotted onto stable base polyester sheets overlaying the photographs. The delineation of seagrass meadows on the stable base sheets was then transcribed employing a best fit approach using a process camera onto maps with survey control and 1:25,000 topographic base information. This line-work was then digitised into the GIS using ArcEdit within the ArcInfo software.

2.1.4 Field Verification Process

In order to ground-truth the aerial photography a field program was designed to take spot surveys throughout the inlets and particularly within the areas of seagrass and other subtidal vegetation.

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The minor inlets presented a challenging environment in which to survey subtidal features. Shallow depths in the inlets makes access by boat very difficult while water clarity is poor with visibility varying from 30 cm up to 2 metres. In order to ground truth such shallow areas a small flat-bottomed punt was employed. A glass plate incorporated into the hull afforded observers an improved view of the subtidal vegetation.

The punt was fitted with a portable Differential Global Positioning System (DGPS). The DGPS enabled accurate location information for the field samples sites to be recorded. Some DGPS readings in Mallacoota however, were considered unreliable due mainly to the steep surrounding terrain posing difficulties in maintaining the differential signal. Where the accuracy of survey locations could not be verified, these sites have not been included in the final field dataset (Appendix 1).

Data sheets were used to record the position, seagrass species type and density as well as substrate type at each site (see below). In addition non-seagrass vegetation and any other observations of relevance were recorded. Observations from each ground-truthing site are presented in Appendix 1.

2.1.5 Field Classifications

Species: Three species of seagrass were recorded during this survey, these were Zostera muelleri, Heterozostera tasmanica and a species of Ruppia (Fig. 2.1). The two species of Zosteraceae, Heterozostera tasmanica and Zostera muelleri, could not be differentiated by a visual inspection from the punt and as a result were grouped into a single species category, “Zostera” (Table 2.1). It should be noted that some authors do not consider species of Ruppia to be true seagrasses, but for the purposes of this study they will be considered as such (Edgar, 1997, Womersley, 1984).

The genus Ruppia has had a history of confused taxonomy at both the species and family level (Jacobs & Brock, 1982). Four species of Ruppia have been recorded in Australia; R. megacarpa, R. polycarpa, R. maritima and R. tuberosa (Jacobs & Brock, 1982, in: Vollebergh & Congdon, 1986). The majority of work on these species appears to have taken place in South Australia although records do exist for Victoria (Brock, 1981). Vollebergh & Condon (1986) stated that there are no published studies for Victorian communities. The lack of information on Ruppia in Victoria and the difficulties in differentiating between the species prevented the identification of Ruppia to species level in the minor inlets. However, given the available literature it is most probable that the Ruppia recorded in Sydenham and Mallacoota inlets is the robust perennial species, Ruppia megacarpa.

In addition to seagrass species, other types of subtidal vegetation were recorded where possible. It was not possible to record all species of algae, so general categories of “Macroalgae” and “Filamentous algae” were used (Table 2.1). Filamentous algae included Chaetomorpha species, which can be fine hair-like green algae forming large mats, either on their own or amongst the seagrass. A record of “Epiphytic algae” was also used to indicate the often heavy algal load growing on the seagrass leaves themselves (Table 2.1). A category of “Intertidal vegetation” was used to describe species such as Spartina (Table 2.1).

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Density: Biomass, density and productivity measurements all indicate the “health” of seagrass meadows (Kirkman, 1995). It was not possible, given the large scale of mapping in this study, to quantitatively assess the biomass of seagrass in the minor inlets. However, an attempt was made to record the density of seagrass meadows. Kirkman (1995) suggests that for species such as Heterozostera tasmanica a visual assessment can be made and then biomass samples taken for each density grade.

As biomass samples were not taken, and underwater photography proved unreliable due to suspended sediments, the assessment of seagrass density in this study is based on visual assessments by the field observers (R.Roob and S.Blake). Categories of “Sparse”, “Medium” and “Dense” seagrass were recorded, representing approximately 0-30%, 31- 60% and 61-100% substrate cover respectively (Table 2.1).

Substrate Type: Where possible the substrate type was also recorded during the field verification and substrate categories are listed in Table 2.1. The category of “No Visible Bottom” was used where either the water depth was too great, water quality was poor or where the substrate was obscured by the subtidal vegetation.

Table 2.1: Classification categories recorded during the field surveys. Classification Categories Attributes Species Zostera (Heterozostera tasmanica and/or Zostera muelleri) Zostera and epiphytic algae Ruppia spp. Ruppia spp. and epiphytic algae Ruppia spp. and Zostera mix Ruppia spp. and Zostera with epiphytic algae Macroalgae Filamentous algae Intertidal Vegetation

Density Sparse Medium Dense

Substrate Type Sand Sand/Mud Sand/Gravel Mud Rock Bare Substrata No Visible Bottom

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Figure 2.1: Seagrasses of the minor inlets a) Heterozostera tasmanica H. tasmanica has an almost identical leaf shape to Zostera muelleri. It can sometimes be separated from other species on the basis of its branching pattern, with the leaves having dark wiry bases that arise vertically from the rhizomes, whereas the leaves of Zostera muelleri are often curved parallel with sediment near their bases (Edgar, 1997). H. tasmanica is generally a subtidal species of seagrass and can only exist where it is exposed to the atmosphere for minimal periods. Heterozostera tasmanica (source G. Edgar) b) Zostera muelleri Z. muelleri generally exists in intertidal zones and requires extended periods of exposure to the atmosphere to survive. Zostera muelleri has at least two roots at each node: the leaf apex is usually notched in the centre, and the leaf blade has three longitudinal veins. The only reliable way to separate these two species of Zostera is to observe a cross-section of the rhizome with a hand-lens or microscope. Heterozostera tasmanica has four to twelve vein like vascular bundles Zostera muelleri (source B. Fuhrer) arranged in a circle, whereas Zostera muelleri has only two (Edgar, 1997). e) Ruppia spp. Species of Ruppia are characterised by their ability to tolerate a wide range of salinities (Womersley, 1984). Members of the Family generally have long narrow leaves and a spike-like flower. They lack a tongue-like membrane at the base of the leaves and have pollen grains that are rounded.

Ruppia sp. (source G. Edgar)

Marine and Freshwater Resources Institute – Page 9 Seagrass Mapping of Victoria’s Minor Inlets 2.2 RESULTS The spatial distribution of seagrass in the minor inlets identified by this study is presented in the maps at the end of this Section (Figures 2.2a-g). These maps also incorporate ground-truthing points recorded during the field work (Appendix 1 and 2). Both the seagrass distribution and ground-truthing points have been recorded in a digital GIS format (see metadata in Appendix 3).

Area summaries for seagrass species and densities at each of the inlets is presented in Table 2.2. The category “Undefined Subtidal Vegetation” which includes macroalgae and filamentous algae has been included in this table and is also included in the pie charts for each inlet below. The bar graph in Figure 2.3 shows the total area of seagrass only, relative to the total area of each inlet. The following sections provide an outline of the seagrass found at each inlet.

2.2.1 Anderson Inlet

Figure 2.4a presents a summary of the seagrass categories for Anderson Inlet (see Table 2.2).

Dense Zostera 28%

Dense Zostera with epiphytic algae Undefined subtidal 0.1% vegetation 61% Medium Zostera 2% Sparse Zostera 7% Sparse Zostera with epiphytic algae 2%

Figure 2.4a: Summary of seagrass categories in Anderson Inlet

Anderson Inlet has a total area of approximately 24.4 km2 of which only 0.4 km2 supported seagrass, representing approximately 2% of the inlet’s area (Fig. 2.3). Areas of “Intertidal Vegetation” were recorded in the western half of the inlet and these were generally stands of Spartina.

Figure 2.2a shows that the majority of Anderson Inlet had a bare substrate. The dominant substrate type was sand, with areas of sand/mud and mud also being recorded in the eastern half of the inlet (Appendix 1).

“Undefined subtidal vegetation” was the dominant subtidal vegetation category, accounting for 61% of the total vegetation cover (Fig. 2.4a). The majority of this was recorded on the intertidal flats in the centre of the inlet.

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Zostera was the dominant seagrass category, accounting for 39% of the total vegetation cover (Fig. 2.4a). Of this, the majority was dense (28%) and sparse (7%). There were also small areas of sparse Zostera with epiphytic algae, dense Zostera with epiphytic algae and medium Zostera. No areas of seagrass were recorded in the western half of the inlet.

2.2.2. Shallow Inlet

Figure 2.4b presents a summary of the seagrass categories for Shallow Inlet (see Table 2.2).

Undefined subtidal Dense Zostera vegetation 6% Dense Zostera with 0.4% epiphytic algae 2% Sparse Zostera with Medium Zostera epiphytic algae 4% 1% Medium Zostera with epiphytic algae 1%

Sparse Zostera 86%

Figure 2.4b: Summary of seagrass categories in Shallow Inlet

Shallow Inlet has a total area of approximately 15.2 km2, of which 8.5 km2 was covered by seagrass. Approximately 56% of the total area of the inlet was covered by Zostera (Fig. 2.3).

Zostera was the dominant subtidal vegetation category in Shallow Inlet, accounting for over 99% of the subtidal vegetation mapped (Fig.2.2b and Fig. 2.4b). Sand was the dominant substrate type, with patches of rock and rock/sand being found near the entrance of the inlet (Appendix 1).

Of the subtidal vegetation recorded, 86% was sparse Zostera, with dense Zostera and medium Zostera comprising 6% and 4% respectively (Fig. 2.4b). Small areas of dense, medium and sparse Zostera, all with epiphytic algae were also recorded. Most of the seagrass was found in the northern half of the inlet where the seagrass cover is almost total (Fig. 2.2b). Less than 1% cover of undefined subtidal vegetation was identified, primarily located near the entrance to the inlet.

The areas of undefined subtidal vegetation generally refer to macroalgae associated with rocky substrate near the entrance. The majority of Zostera was found in the northern half of the inlet, with sparse Zostera dominating the intertidal flats and dense stands colonising the sides of the deeper channels.

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2.2.3. Sydenham Inlet

Figure 2.4c presents a summary of the seagrass categories for Sydenham Inlet (see Table 2.2).

Dense Ruppia/Zostera mix Undefined subtidal 4% Dense vegetation Ruppia/Zostera mix 9% with epiphytic algae 1% Sparse Zostera 4%

Medium Zostera 23%

Dense Zostera 58% Medium Ruppia 1%

Figure 2.4c: Summary of seagrass categories in Sydenham Inlet

Sydenham Inlet has a total area of approximately 10.5 km2, of which 3.5 km2 was covered by seagrass. Approximately 33% of the total area of the inlet was covered by Zostera (Fig. 2.3).

Zostera was the dominant subtidal vegetation category in Sydenham Inlet, accounting for 85% of the subtidal vegetation (Fig. 2.2c and Fig. 2.4c). Substrate type was a mixture of sand, sand/mud and mud (Appendix 1). Areas of mud and sand/mud were present in Bobs Bay and West of The Mahoganys, while sand was the more dominant substrate in the east and near the mouth of the inlet (Fig. 2.2c).

Dense Zostera accounted for 58% of the subtidal vegetation, with 23% medium Zostera and 4% sparse Zostera (Fig. 2.4c). Ruppia was also recorded in Sydenham Inlet, present as either monospecific stands or mixed with Zostera, and accounted for 6% of the vegetation (Fig. 2.4c). Approximately 9% of the subtidal vegetation was undefined.

Zostera was found around most of the inlet with dense Zostera most common in the deeper areas and medium Zostera occurring on the shallow flats. Ruppia was found only in the western arm of the inlet. Areas of undefined subtidal vegetation were present in Bobs Bay and at the western end of the inlet known as Siberia (Fig. 2.2c).

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2.2.4. Tamboon Inlet

Figure 2.4d presents a summary of the seagrass categories for Tamboon Inlet (see Table 2.2).

Undefined subtidal vegetation Sparse Zostera 1% 17%

Medium Zostera with epiphytic algae 2%

Medium Zostera 19% Dense Zostera 61%

Figure 2.4d: Summary of seagrass categories in Tamboon Inlet

Tamboon Inlet has a total area of approximately 6.2 km2, of which 1.1 km2 was seagrass. Approximately 18% of the total area of the inlet was covered by Zostera (Fig. 2.3).

Zostera was the dominant vegetation category in Tamboon Inlet, accounting for 99% of the subtidal vegetation (Fig. 2.2d and Fig. 2.4d). Sand was the only substrate type recorded (Appendix 1).

Of the subtidal vegetation recorded, 61% was dense Zostera, 19% medium, 17% sparse and 2% medium Zostera with epiphytic algae. A small area of undefined subtidal vegetation was also recorded (1%).

Dense Zostera occurred around most of the periphery of the inlet, with the exception of an area of bare shallow sediment at the mouth of the inlet and patches of sparse and medium Zostera growing around the entrance of the tributary (Fig. 2.2d). An area of Zostera with epiphytic algal and a patch of filamentous algae were located near the entrance of the inlet to the sea.

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2.2.5. Wingan Inlet

Figure 2.4e presents a summary of the seagrass categories for Wingan Inlet (see Table 2.2).

Sparse Zostera Medium Zostera 1% 15%

Dense Zostera with epiphytic algae 1%

Dense Zostera 83%

Figure 2.4e: Summary of seagrass categories in Wingan Inlet

Wingan Inlet has a total area of approximately 1.2 km2, of which 0.6 km2 was seagrass. Approximately 51% of the total area of the inlet was covered by Zostera (Fig. 2.3).

Zostera was the dominant subtidal vegetation category in Wingan Inlet, accounting for all of the vegetation (Fig. 2.2e and Fig. 2.4e). Substrate type was a mixture of sand and mud (Appendix 1). Muddy substrate was present throughout the centre of the inlet, with sand substrate being more common around the mouth of the inlet and the tributary entrance (Fig. 2.2e).

Dense Zostera accounted for 83% of the total area of subtidal vegetation, with medium Zostera accounting for 15% and sparse accounting for 1% (Fig. 2.4e). Approximately 1% of the subtidal vegetation was dense Zostera with epiphytic algae.

Dense Zostera was widely distributed through the southern half of the inlet, with a general decrease of density in the northern half (although areas of dense Zostera still occur). Patches of bare sediment were present throughout the inlet, the largest being at the mouth.

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2.2.6. Mallacoota Inlet

Figure 2.4f presents a summary of the seagrass categories for Mallacoota Inlet (see Table 2.2).

Dense Ruppia 9% Dense Ruppia with Sparse Zostera epiphytic algae 15% 8% Sparse Ruppia Dense 4% Ruppia/Zostera mix Medium Zostera 5% with epiphytic algae Dense 1% Ruppia/Zostera mix Medium Zostera with epiphytic algae 9% 0.5% Medium Ruppia/Zostera mix 0.1% Medium Ruppia 1% Dense Zostera Dense Zostera with 48% epiphytic algae 0.1%

Figure 2.4f: Summary of seagrass categories in Mallacoota Inlet

Mallacoota Inlet has a total area of approximately 30 km2, of which 6.5 km2 was seagrass. Approximately 22% of the total area of the inlet was covered by a mixture of Zostera and Ruppia (Fig. 2.3).

Zostera was the dominant subtidal vegetation category in Mallacoota Inlet, accounting for 73% of the subtidal vegetation (Figs. 2.2f-g and Fig. 2.4f). Substrate type was predominantly sand, with areas of mud present south of Howe Bight (Fig. 2.2f) and around some of the tributary entrances (Appendix 1). Although not widespread, areas of gravel and rock were also present.

Dense Zostera accounted for 48% of the total area of subtidal vegetation, with sparse and medium Zostera accounting for 15% and 9% respectively (Fig. 2.4f). Small areas of dense and medium Zostera with epiphytic algae were also present (<2%). Ruppia was relatively common in Mallacoota Inlet, often associated with heavy epiphytic algal loads, and accounted for 22% of the total subtidal vegetation mapped. A mixture of Ruppia and Zostera accounted for a further 6%.

Zostera was widely distributed throughout the inlet with the largest area found in the southern half, located on the shallow sandbanks of Bottom Lake near the Mallacoota township (Fig. 2.2f). In the northern half of Bottom Lake and throughout Top Lake (Fig. 2.2g) only a narrow band of predominantly dense Zostera existed around the periphery of the inlet. Ruppia beds were restricted to the Bottom Lake being densest around the Goodwin Sands area.

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Table 2.2.: Summary Area Statement of Seagrass Categories Recorded in the Minor Inlets (including Undefined Subtidal Vegetation).

Vegetation Categories Anderson Shallow Sydenham Tamboon Wingan Mallacoota Total Inlet Inlet Inlet Inlet Inlet Inlet Area (m2) Area (m2) Area (m2) Area (m2) Area (m2) Area (m2) Area (m2) Dense Zostera 293,906 505,420 2,180,598 711,055 509,075 3,133,512 733,566 Dense Zostera/Epiphytic Algae 1,155 149,270 8,971 7,386 166,782 Dense Zostera/Ruppia 169,188 319,275 488,463 Dense Zostera/Ruppia/Epiphytic Algae 26,071 32,375 58,446 Medium Zostera 22,829 299,318 883,054 217,227 90,819 581,109 2,094,356 Medium Zostera/Epiphytic Algae 110,574 21,964 74,403 206,941 Medium Zostera/Ruppia 8,064 8,064 Sparse Zostera 74,670 7,354,995 142,426 190,117 3,971 987,367 8,753,546 Sparse Zostera/Epiphytic Algae 16,654 83,562 100,216 Dense Ruppia 628,137 628,137 Dense Ruppia/Epiphytic Algae 508,954 508,954 Medium Ruppia 36,813 69,846 106,659 Sparse Ruppia 292,079 292,079 Undefined Subtidal Vegetation 639,877 29,694 346,905 11,177 1,027,653

Total area (m2) seagrass only (not including 409,214 8,503,139 3,438,150 1,140,363 612,836 6,642,507 20,746,209 undefined subtidal vegetation) Total area (m2) 1,049,091 8,532,833 3,785,055 1,151,540 612,836 6,642,507 21,773,862

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35

30

25

20

Inlet Area Seagrass Area Area (Km2) 15

10 (56%)

(22%)

5 (33%)

(18%) (2%) (51%) 0 Anderson Inlet Shallow Inlet Sydenham Inlet Tamboon Inlet Wingan Inlet Mallacoota Inlet Inlets

Figure 2.3: Bar graph of total seagrass areas against the total area of each inlet (percentages in parentheses indicate proportion of seagrass area relative to total inlet areas).

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2.3 DISCUSSION Most of the inlets had a cover of seagrass ranging from 18% to 56% of the total inlet area (Fig. 2.3). Anderson Inlet was an exception, having a very low seagrass cover of only 2% of the total inlet area. Shallow Inlet and Wingan Inlet had the highest percentage seagrass cover of 56% and 51% respectively.

Zostera was the dominant subtidal vegetation category recorded during this study and was found in each of the minor inlets. Zostera was the only seagrass category recorded in Anderson, Shallow, Tamboon and Wingan Inlets. Species of Ruppia were also recorded in Sydenham and Mallacoota Inlets. Ruppia mixed with Zostera was present in Sydenham Inlet and accounted for approximately 5% of the total vegetation cover. Mallacoota Inlet also had a 5% cover of Ruppia/Zostera, while monospecific beds of Ruppia accounted for 22% of the total subtidal vegetation cover in the inlet.

Some degree of epiphytic algal load on the seagrass was present in all of the inlets. Anderson, Sydenham, Tamboon and Wingan Inlets had relatively low amounts (up to 2% percentage cover) while 4% of the total vegetation cover in Shallow Inlet had epiphytic algae associated with the Zostera beds. In Mallacoota, 10% of the total vegetation cover had similar algal loadings, but it was generally associated with dense monospecific beds of Ruppia (Fig. 2.4f). It is possible that the very “dense” nature of Ruppia beds reduces water movement thereby increasing the ability of epiphytic algae to settle.

Sediment types in the minor inlets were predominantly sand, mud or a mixture of both. No correlation was observed between seagrass distribution and sediment type. Dense beds of Zostera were found growing on muddy substrate in Sydenham and Wingan Inlet (Fig. 2.2c and 2.2e), and on sandy substrate in Shallow and Tamboon Inlets (Fig. 2.2b and 2.2d).

The distribution of seagrass across the minor inlets did not appear to follow any overall visible pattern, although some similarities between groups of inlets can be observed. Seagrass distribution in Mallacoota, Sydenham, Tamboon and Wingan Inlets (Figs. 2.2c-g) shows the influence of depth with most of the seagrass being found on shallow flats and around the shores of the inlets up to depths of approximately 2 m and predominantly in depths of up to approximately 1 m. The depth in these inlets increases relatively quickly in places near the banks, hence the narrow band of seagrass that was observed around the shores. This is particularly noticeable at the Top Lake and northern half of Bottom Lake in Mallacoota Inlet and in Tamboon Inlet (Figs. 2.2d, f, g).

The central areas of Tamboon, Sydenham and Mallacoota Inlets, not including Goodwin Sands, could not be mapped due to poor visibility through the water column and have been classified as having “no visible bottom”. The factors which prevented mapping of the inlet floor in these areas are the same conditions that also typically prevent light reaching the inlet floor and would be expected to limit growth of vegetation. As a result, while it is possible that some additional subtidal vegetation may be present in these areas, it is considered unlikely that this vegetation would be extensive seagrass beds (Table 2.2 & Fig. 2.3).

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Anderson and Shallow Inlets are subject to a greater tidal influence than the other inlets and while they have some physical similarities, they displayed very different seagrass characteristics with Anderson Inlet having the lowest seagrass cover (2 %) and Shallow Inlet the highest cover (56 %). The majority of seagrass in Shallow Inlet was sparse Zostera, covering most of the intertidal flats in its northern half (Fig. 2.2b). Dense stands of Zostera were found in the deeper channels within the intertidal flats and in a band following the banks of the deep channel which bisects Shallow Inlet. The increased density of seagrass growing in these locations may indicate more favourable conditions for seagrass present in the transition zone between the deep subtidal areas and the intertidal zone. These areas are primarily shallow subtidal and the regular tidal exchange would act to flush sediment and other debris from the water column.

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IMPORTANT NOTE

IN ORDER TO REDUCE THE SIZE OF THIS FILE THE MAPS FROM THIS SECTION HAVE BEEN EXTRACTED AND PLACED IN A SEPARATE PDF FILE: MINOR INLETS MAPS.PDF

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3. ASSESSMENT OF HISTORIC SEAGRASS CHANGES IN THE MINOR INLETS

This section presents the results of an assessment of seagrass changes in the minor inlets through firstly, a review of previous research and secondly, a qualitative assessment of historic aerial photography.

3.1 Background

In the late 1970’s and early 1980’s large declines in seagrass habitat were reported at a local, national and international level (Poore, 1978 and Bulthuis & Woelkerling, 1983). Recovery has since been observed in some areas, though not in all. Factors that may contribute to the decline of seagrass include:

· Climate change · Nutrient changes · Desiccation · Toxicants · Succession · Oil spills · Grazing · Pesticides · Diseases · Salinity fluctuations · Suspended sediment · Pollution · Physical disturbance (boats / people)

Seagrasses exhibit distribution patterns caused by availability and suitability of sediment types as well as depth and quality of water. The distribution of different species of seagrasses can depend on when and where they are established. For example Zostera muelleri tends to colonise in higher intertidal areas, while Heterozostera tasmanica generally occurs in the subtidal regions.

Many cases of seagrass decline are considered to have resulted from human activities. A common hypothesis used to explain major seagrass loss is the reduction of light reaching seagrass, which inhibits photosynthesis and therefore growth. Possible causes for this reduction in light may be an increase in turbidity, smothering by increased sedimentation and an increase in epiphyte growth on seagrass leaves (Poore 1978, Bulthuis & Woelkerling 1983).

3.2 Previous Studies

An extensive literature search found only a limited amount of previous research and reports relevant to seagrass in the minor inlets. Previous studies such as the Bays and Inlets Scalefish Fisheries Review (Gunthorpe et al., 1997) also found a similar lack of previous research and available information. An overview of the limited available literature for each inlet is given below.

The only existing quantitative assessment of seagrass distribution in the minor inlets, was undertaken by Saenger and Bucher (1989) although no species information was recorded. A comparison between seagrass areas identified by Saenger and Bucher (1989) and those found in this study is presented in Table 3.1.

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Table 3.1: Comparison of seagrass areas 1989 and 1999. Inlet Seagrass area km2 Saenger and Bucher, 1989 This study 1999 (Table 2.2) Anderson Not recorded 0.5 Shallow 0.57 8.5 Sydenham 1.65 3.5 Tamboon 0.19 1.1 Mallacoota 0.23 6.5 Wingan 0.06 0.61

It can be seen from Table 3.1, that substantial differences exist between the seagrass areas reported in 1989 and those identified in this study. The Saenger and Bucher (1989) study was a broad scale inventory of a wide range of physical and biological characteristics of estuaries throughout Australia. As such, the estimation of seagrass areas was only one of several parameters identified in the Victorian minor inlets and this was based on an assessment of aerial photography alone without any field verification. Poor water clarity in the minor inlets presents considerable difficulties for identifying seagrass areas from aerial photography alone and this probably resulted in an underestimation of seagrass areas by the 1989 study (D.Bucher, pers.comm.).

3.2.1 Anderson Inlet

A proposed management plan for Anderson Inlet (DCNR, 1994) stated that seagrass was the dominant vegetation of the inlet floor covering large expanses of the mudflats, although its species composition was not described. This statement contrasts markedly with this study which found only limited seagrass in Anderson Inlet and undefined subtidal vegetation (non-seagrass) to be the dominant aquatic vegetation.

It has been suggested that the spread of Spartina may have reduced the amount of suitable seagrass habitat in the inlet and there is also anecdotal evidence that suggests occasional seagrass die-off events over the past 20 years (Harrison et al., 1990, in: Gunthorpe et al., 1997).

3.2.2 Shallow Inlet

A proposed management plan for Shallow Inlet (DCFL, 1990) identified the presence of both Zostera muelleri and Heterozostera tasmanica in the inlet. Zostera muelleri was the most abundant seagrass and was widespread on the intertidal flats usually above low tide. Zostera muelleri generally formed sparse beds particularly in sandy areas, but areas became denser in finer sediments. Beds of Heterozostera tasmanica were restricted to slightly deeper water adjacent to the main channels (DCFL, 1990).

There have been no detailed surveys of the benthic communities, marine algae or phytoplankton in Shallow Inlet. However, anecdotal evidence exists for Anderson Inlet suggesting there have been occasional seagrass die-off events over the past 20 years (Harrison et al., 1990, in: Gunthorpe at al., 1997). There have also been local reports of occasional increases in algal growth that suggests the inlet has become

Marine and Freshwater Resources Institute – Page 28 Seagrass Mapping of Victoria’s Minor Inlets nutrient enriched to some extent since the adjacent land was cleared for agriculture in the 1940’s.

3.2.3. Sydenham Inlet

Very little relevant seagrass literature was found for Sydenham Inlet. Brown and Lavery (1977) described the southern shore and East channel areas as having “weeds”, which may have been a reference to seagrasses. Local fishermen in Sydenham Inlet suggest seagrass cover, and distribution, have fluctuated regularly over the past 50 years (Don Cuningham, pers. comms).

3.2.4 Tamboon Inlet

In a review of commercial fisheries in Tamboon Inlet, it was noted that seagrass was abundant at depths of less than 2 m in the inlet and the lower reaches of the Cann River (Winstanley, 1985). Hawkins (1989) recorded ‘weeds’ around the periphery of the northern half of the estuary, with some also in the south which may have been a reference to seagrasses.

3.2.5 Wingan Inlet

No relevant seagrass literature was found for this inlet other than Saenger and Bucher (1989) described previously.

3.2.6 Mallacoota Inlet

Very little relevant seagrass literature was found for this inlet. An assessment of commercial fisheries in the inlet noted that severe flooding, as occurred in 1971, can cause substantial loss of seagrass beds, resulting in reduced catches of some fish species for several years (MacDonald et al., 1994).

3.3 Selection of Historic Aerial Photography and Study Sites

Following the literature review a qualitative assessment of seagrass changes in the minor inlets was undertaken based on historic aerial photography. Aerial photography flown for this study in 1999 was used to identify potential study sites for comparison with historic aerial photographs. Study sites were selected on the basis of the presence of a good coverage of seagrass in 1999 and also the likelihood of the inlet floor being visible at the site under differing water clarity conditions in previous years.

In order to identify historic aerial photographs available for the six minor inlets, a search was undertaken using the aerial photograph database maintained by the Central Plan Office (CPO) of the Office of the Surveyor General. Aerial photograph run index map sheets for the region were also checked to ensure that all the available photographs had been identified.

Aerial photographs for potential study sites within each inlet were assessed in terms of quality and clarity for interpreting seagrass (Appendix 4). Most of the historic aerial photography was flown for terrestrial mapping and was found to be unsuitable for

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interpreting seagrass due to influences such as excessive sun-glare, poor water clarity and low photo resolution. As a result, only four sites located within Mallacoota Inlet, Shallow Inlet and Sydenham Inlet (two separate sites) were found to have enough photographs of suitable quality, at appropriate time intervals and over a sufficient time period to assess seagrass changes. These sites are outlined below.

A summary of the historic aerial photographs selected for the four study sites is given in Table 3.2. Full details of these photographs and all historic photographs assessed for use in this study are given in Appendix 4.

Table 3.2. Aerial photographs available for the study sites (photographs used are represented by shaded cells). Aerial Photographs Shallow Inlet Sydenham Sydenham Mallacoota Year & Format Scale Inlet Site 1 Inlet Site 2 Inlet 1969 Colour 1:12000 1972 BW 1:25,000 1973 BW 1:25,000 1973 Colour 1:25,000 1977 BW 1:10,000 1981 BW 1:32,000 1982 BW 1:25,000 1986 Colour 1:10,000 1987 BW 1:40,000 1987 Colour 1:20,000 1990 Colour 1:40,000 1991 Colour 1:25,000 1993 Colour 1:10,000 1994 Colour 1:20,000 1999 Colour 1:20,000

All aerial photographs reproduced in this report from prior to 1997 are Crown (State of Victoria) Copyright, reproduced with permission of Land Victoria, Department of Natural Resources and Environment.

3.4 Interpretation of Historic Aerial Photography

The historic aerial photographs (Table 3.2) were digitally scanned and reproduced at a common scale of approximately 1:10,000 (Photographs 3.1a-g). Some variations in scale and orientation can be observed between photographs for the same site as they have been manually manipulated using a desktop publishing software and were not digitally geo-registered.

Two categories were used to describe the distribution of seagrass from historic photography:

· Area: represents an estimate of the area of seagrass cover.

· Density: represents an estimate of the density of the seagrass within an area of seagrass

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These categories are entirely qualitative and were based on a visual interpretation and comparison of the historic photography. Historic photography cannot be verified in the field and as a result it was not possible to verify the accuracy of any of these interpretations.

Both area and density were described as high, medium and low or in terms of relative changes in cover from previous years. Observations on density were based on the darkness of the seagrass beds. As a seagrass bed becomes less dense more of the underlying substrate becomes visible and the bed appears lighter in colour.

3.5 Observations from Historical Photography

3.5.1 Shallow Inlet

The study site (labelled A in Figure 3.1) is situated in the centre of the Inlet on the mudflats to the east of the main channel. Aerial photographs suitable for seagrass assessment were available from November 1972, January 1981, February 1987, January 1991, April 1993 and April 1999.

H A T RA W A WA R AT A H

D A O R M R e TE a O S n F

R O A D D OA R

S H H i A g h L L O S W M A D A

Shallow Inlet W W A R ATA ta H er

RO AD

K E RE I C N L E T

M ea n N O RS E T H A S P FI

D OA R

OT C SA L L ND Y E H Sh a lol w S I n le t

P O IN T R O A D

FO ST ER D OA Dr R ain

B o r e

RO A D A

SAN D Y H i gh

w a t e r

R A L L MI

me a n

P O INT

RO AD

ans Creek Fisherm

H i g h

R LA L MI NE L A

R RE N W A BAY

W ta er

HE LL I S O N S

M e a WARATAH n

N (f o u r wh e e l dr iv e )

BAY 1 0 1 2 Kilometers W E

S

Figure 3.1. Location of Shallow Inlet study site.

In 1972 (Photo. 3.1a) the area of seagrass cover on the bank at this site was low (this was the year with the lowest area cover) with a medium density. In 1981 (Photo. 3.1b) there was a slight increase in area of seagrass cover, but there appears to have been a decrease in density. In 1987 (Photo. 3.1c) there was again an increase in the area of seagrass to a medium cover, with an increase in density to a medium level similar to 1972. The greatest area of seagrass cover was in 1991 (Photo. 3.1d) with a

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medium density over most of the bank. In 1993 (Photo. 3.1e. infra-red) the area of seagrass cover shows a marked decrease as well as a decrease in the density. The 1999 photo (Photo. 3.1f) appears to show a continuation in the pattern from 1991, with a further decrease in the area of seagrass cover which encompasses an area of medium density surrounded by sparse seagrass.

It would appear from the historic aerial photographs that there has been a reasonably stable area of seagrass cover in the study area. The area covered by seagrass and density appears to have been very similar for the years 1972, 1981, 1987 and 1999, with a large increase in area in 1991 and then a dieback by 1993. However, as some of the photographs were taken up to nine years apart, it is difficult to draw definite conclusions regarding the historical fluctuations of seagrass in this Inlet.

3.5.2 Sydenham Inlet

Two sites were examined at Sydenham Inlet. Site 1 is near the entrance to the Inlet and Site 2 is located at the mouth of the Bemm River (Fig. 3.2.).

Lit tle MM RIVER BE weather onyl ) (Dry R iv er

S Y D AD E B RO N MORG H E AN A M M M R BOBS E RIVER V er BAY RI v Ri

IN E LE D M T P ittle TO M r L adssubject to IL URI E ve TRA ST B Ri sonalclosure M R A e OA H Littl D N DE Y S Site 2

SYDENHAM INLET

Site 1

Siberia

The Mahoganys

Sydenh am Inlet

water mean

N

1 0 1 2 Kilometres W E mean S

Figure 3.2. Location of Study Sites 1 and 2, Sydenham Inlet.

Site 1 is located to the north of the main channel entrance that leads into the inlet from the ocean (Fig. 3.2.). Suitable aerial photographs for seagrass interpretation were available from March 1973, January 1977, March 1982, November 1986, January 1987, March 1990 and April 1999.

Most of the historic photographs for Site 1 in Sydenham Inlet have a medium and often patchy, area of seagrass cover. The area and density of seagrass in the 1973 and

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1977 photographs (Photos. 3.2a and 3.2b respectively) appears to be very similar, both showing a sparse cover of seagrass with a very patchy distribution. The 1982 photograph (Photo 3.2c) is a little unclear but shows an increase in the area of seagrass cover, an increase in density and a much less patchy distribution. In 1986 (Photo 3.2d) the density has decreased although the area of seagrass cover remains greater than 1977. A similar pattern is present in the 1987 photograph (Photo 3.2e), with an apparent decrease in area and density (bare sandy areas becoming more visible). The 1990 photograph (Photo 3.2f) is difficult to interpret although it appears the area and density of seagrass has increased. An even distribution of medium density seagrass is visible in the 1999 photo (Photo 3.2g), and this would appear to be the year with the highest density and area of seagrass cover.

The Site 2 study area is situated on the bank to the north of the entrance of the Bemm River (Fig. 3.2.). Suitable aerial photographs for seagrass interpretation were only available from January 1986, January 1987, March 1990 and April 1999.

The 1986 and 1987 historic photographs (Photos. 3.2h and 3.2i respectively) both show a similar distribution and cover of seagrass in the study area, with very little seagrass in 1986 and none the following year (this was the year with the lowest area cover). In contrast, the following two photographs, 1990 (Photo. 3.2j) and 1999 (Photo. 3.2k), show an increase in the area of seagrass cover, with medium density beds having established on the previously unvegetated sediments.

While the lack of photographs for this Inlet make it difficult to detect small scale changes in area and density, it appears both sites generally had a poor or sparse patchy cover of seagrass in the late 1980’s, which then increased to a medium density in the 1990’s.

3.5.3 Mallacoota Inlet

The study site in Mallacoota, labelled A (Fig. 3.3) is a sandbank in the channel between Rabbit and Goat Islands located to the west of the Mallacoota township.

Suitable aerial photographs for seagrass interpretation were available from April 1969, March 1973, October 1977, November 1986, March 1990, 1994 and April 1999.

The 1969 photograph (Photo 3.3a) shows dense seagrass covering the majority of the bank, with the exception of the western end which appears to have been bare. The 1973 photograph (Photo 3.3b) is not as clear as the other photographs, but appears to show an increase in light areas on the bank, which would indicate a decrease in the area and density of seagrass. In 1977 (Photo 3.3c) there is a further decrease in the area of seagrass cover and the density on the bank becoming sparse with the western half of the bank being bare (this was the year with the lowest area cover).

In 1986 (Photo 3.3d) a recovery of the seagrass on the western end of the bank can be observed with the whole bank having a medium to patchy cover of dense seagrass. The 1990 photograph (Photo 3.3e) shows a dense cover of seagrass across the entire bank (possibly 100% cover) with no visible bare patches. The 1994 photograph (Photo 3.3f) is a little unclear but it would appear that the bank still has a high cover

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of dense seagrass. In 1999 (Photo 3.3g) the photograph once again shows a very dense seagrass area covering the entire bank.

Teal wlel C Do re ek

Sm le ley

Cr R eek y I Ba VE n R Hor pe Ca Muddy Smelley MALLACOOTA ek Cre Inlet Inlet n pe Hor Ca MALLACOOTA INLET MALLACOOTAINLET INLET

Creek S potted LeesBight

Dog

Creek

CemeteryBight

Creek

ss Gra

ek d e wor Cr S y lCa e Tr k ee IsmanInlet pe Cr i a P Te DorronBight

BakerBight

Dou Refuge ble Cove

Mosquito ek Cre Cre K ek ni gf ihs Creek GOODWIN SANDS an pti ek Ca C MALACOOTA e er Cr ke INLET

MALLACOOTA INLET HoweBight e Howe rli ha C C reek

t Mulel Cr eek k e rC Mile

Two

S had y N

Sh el e C ann pe ree A Ch Mallacootak on W E ris Har S

Davis S at it on Creek

Develings 1 0 1 2 Kilometers Inlet

Figure 3.3. Location of Study Site, Mallacoota Inlet.

The pattern at this site over the past 30 years seems to have been one of decline, followed by regrowth. In the 60’s and 70’s the distribution and density of seagrass decreased with a noticeable pattern of seagrass decline from west to east across the bank until 1977, when the western half was bare and the bank had its lowest area of seagrass cover. The seagrass seems to have recovered during the 1980’s and recolonised the western end of the bank resulting in the highest area of seagrass cover and density in the early 90’s, and continuing through to the late 90’s.

Marine and Freshwater Resources Institute – Page 34 Seagrass Mapping of Victoria’s Minor Inlets

Photo. 3.1a: Shallow Inlet Site, 28th November 1972 (approx scale 1:10,000)

Photo. 3.1b: Shallow Inlet Site, 13th January 1981 (approx scale 1:10,000)

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Photo. 3.1c: Shallow Inlet Site, 7th February 1987 (approx scale 1:10,000)

Photo. 3.1d: Shallow Inlet Site, 3rd January 1991 (approx scale 1:10,000)

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Photo. 3.1e: Shallow Inlet Site, 18th April 1993 (approx scale 1:10,000)

Photo. 3.1f: Shallow Inlet Site, 25th April 1999 (approx scale 1:10,000)

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Photo 3.2a: Sydenham Inlet Site 1, 11 March 1973 (approx scale 1:10,000)

Photo 3.2b: Sydenham Inlet Site 1, 8th January 1977 (approx scale 1:10,000)

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Photo 3.2c: Sydenham Inlet Site 1, 3rd March 1982 (approx scale 1:10,000)

Photo 3.2d: Sydenham Inlet Site 1, 4th Nov 1986 (approx scale 1:10,000)

Marine and Freshwater Resources Institute – Page 39 Seagrass Mapping of Victoria’s Minor Inlets

Photo 3.2e: Sydenham Inlet Site 1, 30th January 1987 (approx scale 1:10,000)

Photo 3.2f: Sydenham Inlet Site 1, 17th March 1990 (approx scale 1:10,000)

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Photo 3.2g: Sydenham Inlet Site 1, 26th April 1999 (approx scale 1:10,000)

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Photo. 3.2h: Sydenham Inlet Site 2, 30th January 1986 (approx scale 1:10,000)

Photo. 3.2i: Sydenham Inlet Site 2, 30th January 1987 (approx scale 1:10,000)

Marine and Freshwater Resources Institute – Page 42 Seagrass Mapping of Victoria’s Minor Inlets

Photo. 3.2j: Sydenham Inlet Site 2, 17th March 1990 (approx scale 1:10,000)

Photo. 3.2k: Sydenham Inlet Site 2, 26th April 1999(approx scale 1:10,000)

Marine and Freshwater Resources Institute – Page 43 Seagrass Mapping of Victoria’s Minor Inlets

Photo. 3.3a: Mallacoota Inlet Site, 7th April 1969(approx scale 1:10,000)

Photo. 3.3b: Mallacoota Inlet Site, 10th March 1973 (approx scale 1:10,000)

Marine and Freshwater Resources Institute – Page 44 Seagrass Mapping of Victoria’s Minor Inlets

Photo. 3.3c: Mallacoota Inlet Site, 8th October 1977 (approx scale 1:10,000)

Photo. 3.3d: Mallacoota Inlet Site, 4th November 1986 (approx scale 1:10,000)

Marine and Freshwater Resources Institute – Page 45 Seagrass Mapping of Victoria’s Minor Inlets

Photo. 3.3e: Mallacoota Inlet Site, 8th March 1990 (approx scale 1:10,000)

Photo. 3.3f: Mallacoota Inlet Site, 1994 (approx scale 1:10,000)

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Photo. 3.3g: Mallacoota Inlet Site, 26th April 1999(approx scale 1:10,000)

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3.6 Results

Table 3.3 broadly summarises the seagrass changes observed between the aerial photographs presented in the previous section. The years in which peaks and lows in seagrass cover were observed at each site, are also identified in Table 3.3.

Table 3.3: Summary of changes, peaks and lows in seagrass at the study sites. Aerial Photographs Shallow Inlet Sydenham Sydenham Mallacoota Year & Format Scale Inlet 1 Inlet 2 Inlet 1969 Colour 1:12000 1972 BW 1:25,000 # 1973 BW 1:25,000 # 1973 Colour 1:25,000 ê 1977 BW 1:10,000 = ê # 1981 BW 1:32,000 é 1982 BW 1:25,000 é 1986 Colour 1:10,000 ê é 1987 BW 1:40,000 ê ê # 1987 Colour 1:20,000 é 1990 Colour 1:40,000 é é é [ 1991 Colour 1:25,000 é [ 1993 Colour 1:10,000 ê 1994 Colour 1:20,000 = 1999 Colour 1:20,000 ê é [ é [ =

Sparse cover (relative to other photographs for the same site) Medium cover (relative to other photographs for the same site) Dense cover (relative to other photographs for the same site) No photograph available for the site and year

é indicates an increase in seagrass cover from the previous photograph. ê indicates a decrease in seagrass cover from the previous photograph. = indicates that only a small change in distribution had occurred since the previous photograph. # indicates the year(s) with the lowest seagrass cover for each site. [ indicates the year(s) with the greatest seagrass cover for each site.

Marine and Freshwater Resources Institute – Page 48 Seagrass Mapping of Victoria’s Minor Inlets

Historic aerial photography assessed in this study revealed a pattern of continual fluctuations in both the density and area of seagrass cover in the minor inlets. Each of the inlets is a separate system, with varying catchment areas and different tidal influences, including some inlets being sealed off from the sea more frequently than others. Despite these differences, a broad pattern of changes in seagrass distribution could be observed across all the inlets.

All four of the study sites showed peak seagrass densities in the 1990’s with the Shallow Inlet and Mallacoota sites peaking in 1991 and 1990 respectively and the two Sydenham Inlet sites peaking in 1999. With the exception of the second Sydenham Inlet site, the lowest seagrass cover at the sites occurred in the 1970’s. This may suggest a possible increase in the cover of seagrass in the inlets over the past 20 years.

A pattern of seagrass changes within the individual inlets is less readily observed. This is compounded by the limited number of available historic aerial photographs suitable for seagrass interpretation. What is apparent however, is the continual loss and re-growth of seagrass over time, lending support to the view that seagrass communities are highly dynamic systems.

3.7 Discussion

Assessing historic aerial photography presents a useful method of identifying broad patterns of seagrass changes in shallow marine environments. However, this study did highlight some of the restrictions and limitations of this approach.

Historic aerial photography cannot be verified in the field which means that any assessment will be qualitative in nature. A number of phenomena observed in the inlets can have the appearance of seagrass beds on aerial photography including drift seagrass and other vegetation which has accumulated in sand ridges on the bed of the inlets. Similarly, algae can appear as seagrass and algae growing amongst seagrass beds can influence visual assessments of seagrass density. This highlights the need for fieldwork to be undertaken to provide a true understanding of the status of seagrass beds observed in aerial photographs.

Historic aerial photography used in this study was typically flown for terrestrial mapping programs, without consideration to conditions suitable for mapping the aquatic environment. Consequently many of the available historic photographs were not suitable due to poor water clarity, high levels of sun glare and excessive surface wind ripples. The impact of adverse climatic and environmental conditions is a major limitation on the use of historic aerial photographs for studies of seagrass and aquatic substrates.

Marine and Freshwater Resources Institute – Page 49 Seagrass Mapping of Victoria’s Minor Inlets

ACKNOWLEDGEMENTS

Penny Morris of MAFRI undertook the interpretation and digital capture of seagrass distribution from aerial photography.

Don Hough and Laurie Ferns of the NRE Parks, Flora and Fauna Division coordinated the project and reviewed the draft report providing invaluable feedback. Additional comments on the draft report were provided by David Ball of MAFRI.

REFERENCES

Blake, S., Roob, R., Patterson, E. and Morris, P. (2000). Victorian Marine Habitat Database, Seagrass, Western Port. Report by the Marine and Freshwater Resources Institute, Queenscliff, Victoria.

Brock, M.A. (1981). The Ecology of Halophytes in the South-east of South Australia. Hydrobiologica, 81: 23-32.

Brown, I.R. & Lavery, P.B. (1977). The Corringle Creek to Sydenham Inlet Coastal Reserve. A resources study with comment on the implication of management.

Bulthuis, D.A., Woelkerling, W.J. (1983). Seasonal Variation in Standing Crop, Density and Leaf Growth Rate of the Seagrass, Heterozostera tasmanica (Martens ex Aschers.) den Hartog in Western Port and Port Phillip Bay, Vic. Australia. Aquat. Bot. 16: 111-136.

Department of Conservation, Forests & Lands – Victoria (1990). Shallow Inlet Marine and Coastal Park Proposed Management Plan.

Department of Conservation and Natural Resources (1994). Inverloch Foreshore Reserve and Anderson Inlet: Proposed Management Plan. Victoria Department of Conservation and Natural Resources, Yarram Region.

Edgar, G.J. (1997). Australian Marine Life - the Plants and Animals of Temperate Waters. Reed Books, 35 Cotham Road, Kew, Victoria. 3101.

Ferns, L. and Hough, D. (Editors) (1999) Environmental Inventory of Victoria’s Marine Ecosystems Stage 3 (Volume 1). Parks, Flora and Fauna Division, Department of Natural Resources and Environment, East Melbourne, Australia.

Gunthorpe, L., Hamer, P., Walker, S. (1997). Bays and Inlets Scalefish Fisheries Review. Influence of Environmental and Habitat Features on Scalefish Catches from Victorian Bays and Inlets. Volume 2. Qualitative assessments of the processes threatening habitat and fish stock in selected Victorian Bays and Inlets. Marine & Freshwater Resources Inst.

Hall, D.N., MacDonald, C.M. (1986). Commercial Fishery Situation Report: Net and Line Fisheries of Port Phillip Bay, Victoria, 1914-1984. Fisheries Division, Victoria. Marine Fisheries Report. No. 10, pp.121.

Marine and Freshwater Resources Institute – Page 50 Seagrass Mapping of Victoria’s Minor Inlets

Harrison, I., Rogers, J., Smith, G., Woodfull, J. (1990). Anderson Inlet: Resources, Issues and Options for Management. Graduate School of Environmental Science, Monash University, Melbourne, Vic. pp. 192.

Hastings, K. (1995). Assessing Seagrass Change Off Western Australia, GIS Asia Pacific.

Hawkins, R. (1989). Creeks and Harbours of the Gippsland Lakes and Eastern Gippsland.

Jacobs, S.W.L. & Brock, M.A. (1982). A Revision of the Genus Ruppia (Potamogetonaceae) in Australia. Aquat. Bot., 14: 325-337.

Jenkins, G.P., Watson, G.F. & Hammond, L.S. (1993). Patterns of Utilization of Seagrass (Heterozostera) Dominated Habitats as Nursery Areas by Commercially Important Fish. Victorian Institute of Marine Sciences Technical Report no. 19; 100 pp.

Jenkins, G.P., May, H.M., Wheatley, M.J., Holloway, M.G. (1997). Comparison of Fish Assemblages Associated with Seagrass and Adjacent Unvegetated Habitats of Port Phillip Bay and Corner Inlet, Victoria, Australia, with Emphasis on Commercial Species. Estuar. Coast. Shelf Sci. 1997 vol. 44, no. 5, pp.569-588.

Kirkman, H. (1995). Baseline and Monitoring Methods for Seagrass Meadows. Journal of Environmental Management (1996). No. 47, pp. 191-201.

Land Conservation Council, Victoria (1986). East Gippsland Area Review: Proposed Recommendations.

Lloyd, D. (1997). Ocean Rescue 2000 - Sea Notes - Seagrass. Environment Australia.

MacDonald, C.M., Winstanley, R.H., Hall, D.N. (1994). Mallacoota Inlet Commercial Fin Fishery 1994. Report No. 2, Fisheries Assessment Report series. Natural Resources and Environment.

Poore, G.C.B. (1978). The Decline of Posidonia australis in Corner Inlet. Marine Studies Group, Ministry for Conservation, Environmental Studies Program Project Report No. 228; 28 pp.

Roob, B. and Ball, D. (1997). Victorian Marine Habitat Database, Seagrass, Gippsland Lakes. A report for Fisheries Victoria, DNRE. The Marine and Freshwater Resources Institute, Queenscliff, Victoria.

Roob, B., Morris, P. and Werner, G. (1998). Victorian Marine Habitat Database, Seagrass, Corner Inlet and Nooramunga. Report by the Marine and Freshwater Resources Institute, Queenscliff, Victoria.

Marine and Freshwater Resources Institute – Page 51 Seagrass Mapping of Victoria’s Minor Inlets

Saenger, P., Bucher, D. (1989). An Inventory of Australian Estuaries and Enclosed Marine Waters. Database – Victoria: The Entire Coastline. ANPWS Unpublished Consultancy Report.

Shaw, M. & Jenkins, G.P. (1992). Spatial Variation in Feeding, Prey Distribution and Food Limitation of Juvenile Flounder Rhombosolea tapirina Gunther. Journal of Experimental Marine Biology and Ecology 165, 1-21.

Tunbridge, B.R. & Rogan, P.L. (1981). A Guide to the Inland Angling Waters of Victoria. 3rd ed. Fisheries and Wildlife Division.

Vollebergh, P.J. & Condon, R.A. (1986). Germination and Growth of Ruppia Polycarpa and Lepilaena cylindrocarpa in Ephemeral Saltmarsh Pools, Westernport Bay, Victoria. Aquat. Bot., 26: 165-179.

Winstanley, R.H. (1985).Commercial Fishery Situation Report : Tamboon Inlet, Marine Fisheries Report No 7. Published by Department of Conservation, Forest and Lands Fisheries and Wildlife Service Commercial Fisheries Branch, East Melbourne

Womersley, H.B.S. (1984). The Marine Benthic Flora of Southern Australia. Part I. D.J. Woolman, Government Printer, South Australia.

PERSONAL COMMUNICATIONS

Danny Bucher: Centre for Coastal Studies, Southern Cross University, Lismore.

Don Cuningham: Recreational fisherman and proprietor Cosy Nook Holiday Accommodation, Bemm River, Sydenham Inlet, Victoria.

Marine and Freshwater Resources Institute – Page 52 Seagrass Mapping of Victoria’s Minor Inlets

APPENDIX 1 GROUND-TRUTHING FIELD DATA SHEETS

All field observations recorded by R. Roob and S. Blake, March 1999.

Marine and Freshwater Resources Institute – Page A1 Seagrass Mapping of Victoria’s Minor Inlets

ANDERSON INLET Thursday 11/03/1999 Species Density Terrain Site No Latitude Longitude Species code Density code Terrain code Observations 1 -38.638450 145.729133 Zostera 4 D 2 Sand 1 Very healthy. No algae. Long blades 2 -38.639417 145.728583 Zostera 4 D 2 Sand 1 Very healthy. No algae. Long blades 3 -38.640633 145.725533 Zostera 4 S 8 Sand 1 Very healthy. No algae. Long blades 4 -38.646467 145.733350 Macroalgae 8 S 8 Rock 3 Logs in water colonised by macroalgae 5 -38.648033 145.746717 Zostera 4 D 2 Sand 1 Long leaves, but with slight algal covering. 6 -38.648533 145.748317 Zostera 4 D 2 Sand 1 Long leaves, but with slight algal covering. 7 -38.649133 145.749850 Zostera 4 D 2 Sand 1 Long leaves, but with slight algal covering. 8 -38.653567 145.765250 Zostera 4 D 2 Sand 1 Long leaves, but with heavier algal covering. 9 -38.654217 145.765483 Zostera 4 S 8 Sand 1 Long leaves, but with heavier algal covering. 10 -38.656050 145.767050 Spartina 10 D 2 Mud 2 Spartina band running along bank to boundary of mangroves. 11 -38.656650 145.769333 Zostera 4 S 8 Sand/Mud 8 Blades not as long and heavy algal covering 12 -38.650433 145.765017 Zostera 4 S 8 Sand 1 Sparse patches 13 -38.650733 145.765883 Zostera 4 D 2 Sand 1 Surrounded by patches of sparse Zostera 14 -38.649517 145.764483 Zostera 4 M 4 Sand 1 Little algae present on leaves 15 -38.648967 145.764083 Zostera 4 D 2 Sand 1 Little algae present on leaves 16 -38.637033 145.763850 Zostera 4 D 2 Sand 1 Little algae present on leaves 17 -38.648983 145.765633 Zostera 4 M 4 Sand 1 Macroalgae present also 18 -38.649150 145.795467 Macroalgae 9 S 8 Sand/Mud 8 Vast intertidal expanse 19 -38.660400 145.799300 Macroalgae 9 S 8 Sand/Mud 8 Small areas of patches 20 -38.654700 145.801817 Macroalgae 9 M 4 Sand/Mud 8 Small patches 21 -38.655300 145.804883 Macroalgae 9 D 2 Sand/Mud 8 Large area of this 22 -38.658533 145.812267 Macroalgae 9 D 2 Sand/Mud 8 Is 30m to our SW 23 -38.661600 145.809833 Macroalgae 9 D 2 Sand/Mud 8 Patches 24 -38.663700 145.818583 Macroalgae 9 D 2 Sand/Mud 8 Patches 25 -38.674000 145.832550 Spartina 10 M 4 Mud 2 Spartina & small mangroves along bank - approx 30-50m to our East 26 -38.678967 145.831533 Spartina 10 M 4 Mud 2 Spartina and small and large mangroves - approx 30-50m to our East 27 -38.679017 145.827067 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 Approx 200-300m to our west is an island of Spartina 28 -38.640450 145.781467 Zostera 4 S 8 Sand 1 Intertidal patches of short plants 29 -38.642083 145.741783 Zostera 4 M 4 Sand 1 Quite healthy. Long leaves with little algae

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SHALLOW INLET Tuesday 9/03/1999 Species Density Terrain Site No Latitude Longitude Species code Density code Terrain code Observations 30 -38.853400 146.182900 Zostera 4 D 3 Sand 1 Dense beds and dense patches of grass 31 -38.856833 146.188033 Zostera 4 M 4 Rock 5 Associated with bommies 32 -38.858467 146.188750 Zostera 4 M 5 Rock 5 Associated with bommies. Lots of Pyura visible 33 -38.861650 146.190667 Macroalgae 8 S 9 Sand 1 Patches of macroalgal drift (not to be mistaken for grass) 34 -38.862450 146.192117 Macroalgae 8 S 9 Sand 1 Drift macroalgae and seagrass caught on logs 35 -38.871033 146.191200 Macroalgae 8 S 9 Rock 3 A lot of dead drift material and rubble 36 -38.870917 146.189083 Macroalgae 8 D 3 Rock 3 Patches visible across the mouth of the bay 37 -38.860500 146.187083 Zostera 4 S 9 Sand/Mud 8 Exposed area-lots of crabs and grass - some filamentous algae (this site actually 100-200m due W of the coordinates) 38 -38.856383 146.186383 Zostera 4 S 8 Sand 1 On and around sandy bommie 39 -38.853583 146.175133 Zostera 4 S 8 Sand 1 On and around sandy bommie 40 -38.852633 146.168367 Zostera 4 S 8 Sand 1 Exposed at low tide 41 -38.850083 146.159900 Zostera 4 S 8 Sand 1 Exposed at low tide - lots of filamentous algae and crabs. Grass visible all over intertidal flat but very sparse 42 -38.845317 146.157833 Zostera 4 M 6 Sand 1 Extensive cover - very high algal loading 43 -38.840483 146.160583 Zostera 4 M 4 Sand 1 High algal loading on the grass 44 -38.834817 146.164533 Zostera 4 M 4 Sand 1 High algal loading on the grass 45 -38.826417 146.167583 Zostera 4 S 8 Sand 1 High algal loading on the grass 46 -38.817333 146.160583 Zostera 4 S 9 Sand 1 High algal loading on the grass 47 -38.815950 146.150500 Zostera 4 S 9 Sand 1 High algal loading on the grass 48 -38.809050 146.147350 Zostera 4 M 4 Sand 1 High algal loading on the grass 49 -38.803300 146.147267 Zostera 4 S 8 Sand 1 High algal loading on the grass 50 -38.803817 146.146267 Zostera 4 D 2 Sand 1 High algal loading on the grass 51 -38.808717 146.144117 Bare 3 Bare 1 Sand 1 No visible biota 52 -38.809833 146.143700 Zostera 4 S 8 Sand 1 Very high algal loading 53 -38.811183 146.146933 Zostera 4 D 2 Sand 1 Very high algal loading 54 -38.816383 146.150117 Zostera 4 M 4 Sand 1 Medium algal loading 55 -38.801033 146.154933 Zostera 4 S 8 Sand 1 Relatively little algae on grass 56 -38.819000 146.143150 Zostera 4 M 4 Sand 1 Little algal cover 57 -38.820617 146.164983 Bare 3 Bare 1 Sand 1 No visible biota 58 -38.825933 146.164783 Zostera 4 S 8 Sand 1 No algal cover 59 -38.831117 146.163783 Zostera 4 S 9 Sand 1 Little algal cover

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SYDENHAM INLET Wednesday 24/03/1999 Species Density Terrain Site No Latitude Longitude Species code Density code Terrain code Observations 60 -37.761817 148.979800 Zostera 4 D 2 Mud 2 very long blades, up to 1m. Water very murky 61 -37.761783 148.982367 Zostera 4 D 2 Mud 2 very long blades, up to 1m. Water very murky 62 -37.760333 148.982683 Zostera 4 D 2 Mud 2 " - some algal growth on leaves 63 -37.758183 148.984317 Zostera 4 D 3 Mud 2 Patches of grass in 0.5m' of water. Shorter leaves

64 -37.757000 148.984883 Zostera 4 D 2 Mud 2 very long blades again ~1m water 65 -37.755583 148.985467 Zostera 4 D 3 Mud 2 very long blades again ~1m water 66 -37.754600 148.986167 Bare 3 Bare 1 Mud 2 1m depth - some small patches (2m diameter) visible 67 -37.754483 148.986617 Bare 3 Bare 1 Mud 2 1m depth - no grass 69 -37.751550 148.983983 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 2 murky water with no bottom or grass visible ~1- 1.3m 70 -37.751567 148.981233 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 2 murky water with no bottom or grass visible ~1- 1.3m 71 -37.752283 148.978317 Macroalgae 9 D 3 Mud 2 0.5m deep - patchy cover of bulls wool 72 -37.754200 148.976717 Macroalgae 9 D 3 Mud 2 0.5m deep - patchy cover of bulls wool 73 -37.756050 148.976367 Macroalgae 9 D 3 Mud 2 0.5m deep - patchy cover of bulls wool 74 -37.757683 148.974967 Macroalgae 9 D 3 Mud 2 0.5-1m deep - large patches of bulls wool 75 -37.759750 148.973767 Zostera 4 D 3 Mud 2 small patches of long grass. Patches pretty sparse 76 -37.762500 148.980917 Zostera 4 D 2 Mud 2 long blades - to near surface 77 -37.764000 148.983133 Zostera 4 D 2 Mud 2 long blades - are deeper though 78 -37.763700 148.984833 Zostera 4 D 3 Mud 2 long blades - are deeper though 79 -37.763333 148.986533 Zostera 4 D 2 Mud 2 long blades - to near surface 80 -37.761967 148.989500 Zostera 4 D 2 Mud 2 long blades - to near surface 81 -37.761267 148.993467 Zostera 4 D 2 Mud 2 Water a little clearer. Grass long still 82 -37.761900 148.996133 Zostera 4 D 2 Mud 8 " - grass is deeper 83 -37.762433 148.997400 Zostera 4 D 2 Mud 8 " - grass shallow 84 -37.762917 148.997950 Zostera 4 D 3 Mud 8 " - and sandy bare patches 85 -37.766417 148.999683 Zostera 4 D 3 Sand 1 sandy (bare) mostly - some patches of grass still visible

Marine and Freshwater Resources Institute – Page A4 Seagrass Mapping of Victoria’s Minor Inlets

SYDENHAM INLET continued 87 -37.763717 149.008567 Zostera 4 S 9 Mud 2 very small stunted patches of grass (<1m diameter) 88 -37.765950 149.002133 Zostera 4 D 8 Sand 1 very sparse stunted growth 89 -37.765417 149.000417 Zostera 4 M 4 Sand 1 patchy distance of small plants & larger plants 90 -37.769117 148.999400 Zostera 4 D 2 Mud 2 very long blades 91 -37.771783 148.999533 Zostera 4 D 2 Sand 1 very long - up to surface - water clear 92 -37.774050 149.000083 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 93 -37.778783 149.006767 Zostera 4 D 2 Sand 1 long patches & patches of shorter grass too 95 -37.777700 149.008967 Zostera 4 D 3 Sand 1 long plants 96 -37.777950 149.008383 Zostera 4 D 3 Sand 1 long plants 97 -37.780083 149.004783 Zostera 4 D 3 Sand 1 " -also a bit of drift grass on surface 98 -37.778750 149.000800 Zostera 4 S 9 Sand 1 short stunted grass, very small patches ( 30cm diameter) 100 -37.773117 148.999050 Zostera 4 D 2 No Vis. Bottom 7 long plants - near surface 101 -37.772400 148.997000 Zostera 4 D 2 No Vis. Bottom 7 long plants - near surface 102 -37.771600 148.994667 Zostera 4 D 2 No Vis. Bottom 7 long plants - near surface 103 -37.772633 148.991700 Zostera 4 D 2 No Vis. Bottom 7 long plants - deeper (may not be visible from photos) 104 -37.774933 148.987800 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 105 -37.777800 148.986017 Zostera 4 D 2 No Vis. Bottom 7 long 106 -37.778433 148.984933 Zostera 4 M 5 Sand 1 long & short plants - along this bank can see the line to which the bay rises when it's blocked off - about 1m plus from present

107 -37.777133 148.979667 Zostera 4 M 5 Sand 1 patchy distance of medium & sparse density 108 -37.776917 148.973567 Zostera 4 S 9 Mud 2 very sparse grass - heavy algal (see sample)

109 -37.776167 148.969933 Fil. Algae 11 D 2 Mud 2 found Ruppia spp. here 110 -37.775167 148.968617 Zostera 4 D 3 Mud 2 sparse patches of dense grass. A lot of fill. algae growing 111 -37.774467 148.965650 Zostera 4 D 2 Mud 2 long blades - some algal loading 112 -37.774417 148.964333 Fil. Algae 11 D 2 Mud 2 bed covered in it 113 -37.772833 148.960417 Zostera 4 D 2 Mud 2 very long blades (~1m) to surface 114 -37.773483 148.957183 Zostera 4 D 2 Mud 2 long blades - to surface

Marine and Freshwater Resources Institute – Page A5 Seagrass Mapping of Victoria’s Minor Inlets

SYDENHAM INLET continued 115 -37.774100 148.955800 Zostera 4 D 2 Mud 2 Long blades to surface. Nothing visible between this point and the next 116 -37.768583 148.953833 Bare 3 Bare 1 No Vis. Bottom 7 117 -37.765933 148.954467 Ruppia 5 M 4 No Vis. Bottom 7 quite a lot of Ruppia seen as drift on surface around here 118 -37.767017 148.961600 Zostera/Ruppia 7 D 2 Sand/Mud 8 dense mix of Ruppia and stunted Zostera. Not too much algal loading. Sand/Mud bottom 119 -37.766900 148.964367 Zostera/Ruppia 7 D 2 Sand/Mud 8 dense mix of Ruppia and stunted Zostera. Not too much algal loading. Sand/Mud bottom 120 -37.767417 148.965900 Zostera/Ruppia 7 D 2 Sand/Mud 8 dense mix of Ruppia and stunted Zostera. Not too much algal loading. Sand/Mud bottom 121 -37.770383 148.969100 Zostera 4 D 2 No Vis. Bottom 7 about here the water drops away - some dense, long Zostera visible 122 -37.768083 148.971000 Zostera 4 D 3 No Vis. Bottom 7 long blades 123 -37.765950 148.973733 Zostera 4 D 3 No Vis. Bottom 7 long blades 124 -37.764433 148.973867 Zostera 4 D 7 Sand 1 short blades

Marine and Freshwater Resources Institute – Page A6 Seagrass Mapping of Victoria’s Minor Inlets

TAMBOON INLET Thursday 25/03/1999 Note: Inlet was closed to the seas and therefore had elevated water levels Species Density Terrain Site No Latitude Longitude Species code Density code Terrain code Observations 125 -37.744733 149.134850 Zostera 4 D 2 Sand 1 long blades - fairly deep 126 -37.747550 149.134883 Zostera 4 S 9 Sand 1 stunted plants with occasional long plants 127 -37.748000 149.133667 Zostera 4 D 3 Sand 1 long blades - quite deep 128 -37.747900 149.133000 Bare 3 Bare 1 Sand 1 no visible flora 129 -37.747067 149.132350 Zostera 4 D 3 Sand 1 long - deep (~0.5m long leaves) 130 -37.746450 149.130233 Zostera 4 D 3 Sand 1 long - deep and shorter plants too 131 -37.747750 149.129300 Zostera 4 S 9 Sand 1 short - shallow 132 -37.747950 149.128517 Zostera 4 M 5 Sand 1 long & short intermixed 133 -37.746683 149.128350 Zostera 4 D 2 Sand 1 long plants - deep 134 -37.745250 149.128400 Zostera 4 D 2 Sand 1 long plants - intermediate depth (~1m) 135 -37.743500 149.129900 Zostera 4 M 5 Sand 1 longer plants and short, intermixed 136 -37.742798 149.128117 Zostera 4 M 5 Sand 1 intermediate length plants (~0.3m long) 137 -37.742000 149.124950 Zostera 4 D 2 Sand 1 intermediate length 138 -37.742167 149.121550 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 139 -37.741883 149.119833 Zostera 4 D 2 Sand 1 long and deep 140 -37.742283 149.118450 Zostera 4 D 2 Sand 1 long and deep 141 -37.743833 149.116600 Zostera 4 D 2 Sand 1 long and intermediate depth 142 -37.745483 149.116200 Zostera 4 D 2 Sand 1 long and intermediate depth 143 -37.746717 149.116417 Zostera 4 D 3 Sand 1 long and intermediate depth 144 -37.748850 149.115433 Zostera 4 D 3 Sand 1 intermediate length and quite deep 145 -37.751250 149.112583 Zostera 4 D 3 Sand 1 Long plants. Similar seagrass all along western boundary of lake

146 -37.756933 149.113536 Zostera 4 D 2 Sand 1 long plants 147 -37.758700 149.116183 Zostera 4 D 2 Sand 1 long plants 148 -37.758050 149.118400 Zostera 4 D 2 Sand 1 long plants - bit more alae on it than around west bank 149 -37.757533 149.122333 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 150 -37.757267 149.125117 Zostera 4 D 2 Sand 1 long plants - very dense 151 -37.757717 149.126033 Bare 3 Bare 1 Sand 1 bare sand 152 -37.758433 149.126217 Zostera 4 D 2 Sand 1 long and thin plants - patches of sand visible 153 -37.761450 149.123433 Zostera 4 D 2 Sand 1 long and shallow 154 -37.765633 149.121400 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 -

Marine and Freshwater Resources Institute – Page A7 Seagrass Mapping of Victoria’s Minor Inlets

TAMBOON INLET continued 155 -37.767033 149.121950 Zostera 4 M 5 Sand 1 fairly long 156 -37.769167 149.122217 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 157 -37.769650 149.122300 Zostera 4 D 2 Sand 1 fairly long - deep water (>2m) here and maybe in this bay generally 158 -37.770283 149.125000 Zostera 4 D 2 Sand 1 long and intermediate. depth 159 -37.771700 149.129567 Zostera 4 D 2 Sand 1 long and very dense 160 -37.771700 149.133667 Zostera 4 D 2 Sand 1 long and dense 161 -37.775833 149.137933 Bare 3 Bare 1 Sand 1 no visible flora 162 -37.777517 149.136783 Fil. Algae 11 D 2 Sand 1 dense mats of filamentous algae in shallow water 163 -37.777317 149.142750 Bare 3 Bare 1 sand 1 sandy holes and rocks 164 -37.778067 149.144167 Zostera 4 M 5 Sand 1 long plants but very heavily loaded with algae (look dead) 165 -37.776950 149.140650 Bare 3 Bare 1 Sand 1 - 166 -37.773417 149.139100 Zostera 4 D 2 Sand 1 long plants - quite heavy algal loading 167 -37.772217 149.137333 Zostera 4 D 2 Sand 1 long plants 168 -37.769383 149.137800 Zostera 4 D 2 Sand 1 long plants 169 -37.765583 149.136583 Zostera 4 D 2 Sand 1 medium long 170 -37.761817 149.135533 Zostera 4 D 2 Sand 1 medium long 171 -37.760383 149.135767 Zostera 4 S 8 Sand 1 bare sand with sparse patches of short grass 172 -37.758233 149.136733 Zostera 4 M 5 Sand 1 medium length ( 20-30cm) 173 -37.756433 149.137183 Zostera 4 M 5 Sand 1 medium length ( 20-30cm) 174 -37.754500 149.137867 Zostera 4 M 4 Sand 1 also found here is possibly Ruppia - see sample 175 -37.750500 149.136817 Zostera 4 S 9 Sand 1 short leaves (<10cm) 176 -37.749350 149.134967 Zostera 4 S 8 Sand 1 short leaves (<10cm) 177 -37.745800 149.134183 Zostera 4 M 7 Sand 1 mixture of all ( short and long plants) 178 -37.744667 149.134383 Bare 3 Bare 1 Sand 1 -

Marine and Freshwater Resources Institute – Page A8 Seagrass Mapping of Victoria’s Minor Inlets

WINGAN INLET 26/03/99 Species Density Terrain Site No Latitude Longitude Species code Density code Terrain code Observations 179 -37.741500 149.497700 Zostera 4 D 2 Mud 2 long (>50cm) - some algal loading depth down to ~2m then cuts off 180 -37.739233 149.497317 Zostera 4 D 2 Mud 2 " -but not as long 181 -37.739100 149.498350 Zostera 4 D 2 Mud 2 solid cover of grass – 30-50cm water - fair algal cover, plants ~30cm 182 -37.739067 149.499900 Zostera 4 M 4 Mud 2 solid cover of long and short plants 183 -37.739000 149.500133 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 184 -37.738617 149.499983 Zostera 4 D 2 Mud 2 long plants 185 -37.737450 149.500083 Zostera 4 D 2 Mud 2 long and shallow 186 -37.735833 149.499900 Zostera 4 D 2 Mud 2 long and shallow 187 -37.734967 149.497833 Zostera 4 M 4 Mud 2 patches of long grass and mud 188 -37.734333 149.497967 Zostera 4 S 8 Mud 2 short plants (up to 15cm) - very shallow water 189 -37.734050 149.497867 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 190 -37.733233 149.496050 Zostera 4 M 4 Mud 2 medium plants 191 -37.732600 149.495417 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 192 -37.732017 149.495133 Zostera 4 M 4 Mud 2 medium plants 193 -37.731067 149.496233 Zostera 4 M 4 Mud 2 medium plants 194 -37.730500 149.496600 Zostera 4 D 2 Sand 1 short plants (<10cm) 195 -37.729450 149.497200 Zostera 4 D 2 Sand 1 short plants (<10cm) 196 -37.727217 149.498000 Zostera 4 D 2 Sand 1 long plants and shorter 197 -37.725000 149.497667 Zostera 4 D 2 Sand 1 long plants - only close to bank 198 -37.720833 149.497033 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 no grass visible - too deep – doesn’t look like there's any further up 199 -37.731333 149.496717 Bare 3 Bare 1 Mud 2 no grass 200 -37.731467 149.496617 Zostera 4 D 2 Mud 2 long plants - heavy algal loading 201 -37.743950 149.498367 Zostera 4 D 2 Mud 2 bank of long grass all along here 202 -37.745517 149.499017 Zostera 4 D 2 Mud 2 bank of long grass all along here 203 -37.747083 149.500350 Zostera 4 D 2 Mud 2 bank of long grass all along here 204 -37.747783 149.501783 Zostera 4 D 2 Mud 2 extensive dense bed of medium length plants - some algal loading (looks brown) 205 -37.746967 149.502733 Zostera 4 D 2 Sand 1 shorter plants 206 -37.748350 149.503500 Zostera 4 D 2 Sand 1 long clean grass in deep water - thick blades - healthy looking

Marine and Freshwater Resources Institute – Page A9 Seagrass Mapping of Victoria’s Minor Inlets

MALLACOOTA INLET 27-30/3/99 Species Density Terrain Site_No Latitude Longitude Species Code Density Code Terrain Code Observations 356 -37.522133 149.763983 Bare 1 Bare 1 Gravel/Sand 4 - 372 -37.496000 149.775150 Bare 1 Bare 1 Mud 2 muddy 267 -37.525167 149.730600 Bare 1 Bare 1 Rock 3 steep rocky sides 289 -37.521017 149.716783 Bare 1 Bare 1 Rock 3 steep sided and rocky 345 -37.521133 149.753967 Bare 1 Bare 1 Sand 1 sand shell bottom - no grass (some further in) 398 -37.512833 149.797550 Zostera 4 D 2 Mud 4 is gravelly here and is no ruppia, not even close in 358 -37.522167 149.769250 Zostera 4 D 2 Gravel/Sand 6 " 359 -37.520900 149.771267 Zostera 4 D 2 Gravel/Sand 6 medium length, quite clean 239 -37.537117 149.789283 Ruppia 5 D 2 Mud 2 240 -37.537700 149.787117 Ruppia 5 D 2 Mud 2 not such heavy algal loading 245 -37.543000 149.781500 Ruppia 5 D 2 Mud 2 342 -37.518700 149.750833 Ruppia 5 D 2 Mud 2 messy 388 -37.493583 149.804767 Ruppia 5 D 2 Mud 2 sparse clumps of ruppia 242 -37.536917 149.783717 Zostera 4 D 2 Mud 2 long 262 -37.540450 149.744400 Zostera 4 D 2 Mud 2 ruppia mixed in too - some algal loading 343 -37.518000 149.750533 Zostera 4 D 2 Mud 2 lot of algae 369 -37.500633 149.774150 Zostera 4 D 2 Mud 2 grass growing in ~2-3m of water - very clear - is still ruppia inside 371 -37.496000 149.773883 Zostera 4 D 2 Mud 2 heavy algae 374 -37.497817 149.778233 Zostera 4 D 2 Mud 2 Medium algae 238 -37.536050 149.790383 Zostera/Ruppia 7 D 2 Mud 2 long quite heavy algae 244 -37.542000 149.784217 Zostera/Ruppia 7 D 2 Mud 2 medium length 403 -37.514400 149.788417 Zostera 4 D 2 Rock 3 see sample - was neptunes necklace and other algae here - looked very marine 232 -37.527833 149.782167 Ruppia 5 D 2 Sand 1 lots of fil. Algae - no zostera. Whole area Ruppia/heavy algal loading/lots of swans/smells 233 -37.529550 149.783567 Ruppia 5 D 2 Sand 1 lots of fil. Algae - no zostera. Whole area Ruppia/heavy algal loading/lots of swans/smells 236 -37.532633 149.792517 Ruppia 5 D 2 Sand 1 341 -37.519500 149.751283 Ruppia 5 D 2 Sand 1 ruppia up to surface 353 -37.528400 149.761250 Ruppia 5 D 2 Sand 1 heavy algal load

Marine and Freshwater Resources Institute – Page A10 Seagrass Mapping of Victoria’s Minor Inlets

MALLACOOTA INLET continued 411 -37.526200 149.785150 Ruppia 5 D 2 Sand 1 “ -shallow water 208 -37.558400 149.759767 Zostera 4 D 2 Sand 1 long broad leaves – some algae 213 -37.558800 149.769583 Zostera 4 D 2 Sand 1 long broad leaves and some algal loading 214 -37.558517 149.770617 Zostera 4 D 2 Sand 1 long broad leaves and some algal loading 215 -37.556667 149.771683 Zostera 4 D 2 Sand 1 medium length plants 216 -37.555267 149.772033 Zostera 4 D 2 Sand 1 long plants – deep water – aquaculture buoys 218 -37.552017 149.775950 Zostera 4 D 2 Sand 1 long plants 220 -37.549167 149.769550 Zostera 4 D 2 Sand 1 medium length plants – found Ruppia on the surface 222 -37.550433 149.767850 Zostera 4 D 2 Sand 1 long – quite heavy algae 223 -37.547717 149.766133 Zostera 4 D 2 Sand 1 long – close to surface 224 -37.546233 149.765700 Zostera 4 D 2 Sand 1 long – close to surface 227 -37.544433 149.763817 Zostera 4 D 2 Sand 1 long 247 -37.545450 149.778367 Zostera 4 D 2 Sand 1 251 -37.543950 149.770833 Zostera 4 D 2 Sand 1 long 253 -37.549667 149.765967 Zostera 4 D 2 Sand 1 long – some algae 254 -37.551067 149.761950 Zostera 4 D 2 Sand 1 long – some algae 255 -37.551983 149.762067 Zostera 4 D 2 Sand 1 long – some algae 258 -37.557433 149.762300 Zostera 4 D 2 Sand 1 medium 279 -37.527967 149.706350 Zostera 4 D 2 Sand 1 in this bay 294 -37.514767 149.722700 Zostera 4 D 2 Sand 1 quite long plants – heavy algae 297 -37.511800 149.707833 Zostera 4 D 2 Sand 1 quite long plants – medium algae 310 -37.505083 149.716800 Zostera 4 D 2 Sand 1 quite long 311 -37.504883 149.721617 Zostera 4 D 2 Sand 1 medium length 312 -37.504433 149.725450 Zostera 4 D 2 Sand 1 medium length 325 -37.507533 149.740850 Zostera 4 D 2 Sand 1 quite long plants – medium algae 330 -37.518433 149.732833 Zostera 4 D 2 Sand 1 fringing – medium length 339 -37.520967 149.748200 Zostera 4 D 2 Sand 1 long plants – quite clean 354 -37.524117 149.761700 Zostera 4 D 2 Sand 1 some ruppia mixed in 365 -37.510600 149.778067 Zostera 4 D 2 Sand 1 ruppia inshore/zostera offshore – at ~1.5-2m ruppia gives way to zostera 401 -37.511833 149.788217 Zostera 4 D 2 Sand 1 quite clean – medium length 402 -37.513883 149.787950 Zostera 4 D 2 Sand 1 quite clean – medium length 406 -37.518550 149.795533 Zostera 4 D 2 Sand 1 medium length, medium algae 234 -37.530333 149.784350 Zostera/Ruppia 7 D 2 Sand 1 medium length and fil. Algae 237 -37.533567 149.793933 Zostera/Ruppia 7 D 2 Sand 1

Marine and Freshwater Resources Institute – Page A11 Seagrass Mapping of Victoria’s Minor Inlets

MALLACOOTA INLET continued 264 -37.535167 149.741633 Zostera/Ruppia 7 D 2 Sand 1 medium leaf length on zostera plants – heavy algal load 368 -37.503350 149.775867 Zostera/Ruppia 7 D 2 Sand 1 ruppia inshore/zostera offshore – at ~1-1.5m ruppia gives way to zostera 379 -37.503117 149.787833 Zostera/Ruppia 7 D 2 Sand 1 medium algae 405 -37.515100 149.793867 Zostera/Ruppia 7 D 2 Sand 1 “ -ruppia inside/zostera outside 260 -37.542400 149.750300 Ruppia 5 D 2 No Vis. Bottom 7 ruppia starts at these coordinates 261 -37.541000 149.747417 Ruppia 5 D 2 No Vis. Bottom 7 some sparse patches – some algal loading 346 -37.522400 149.753583 Ruppia 5 D 2 No Vis. Bottom 7 shallow water – little algae 347 -37.523650 149.752833 Ruppia 5 D 2 No Vis. Bottom 7 shallow water – little algae 352 -37.530183 149.761400 Ruppia 5 D 2 No Vis. Bottom 7 heavy algal load 394 -37.499883 149.800167 Ruppia 5 D 2 No Vis. Bottom 7 shallow here so just ruppia 410 -37.524633 149.785117 Ruppia 5 D 2 No Vis. Bottom 7 heavy algal load 413 -37.530200 149.785967 Ruppia 5 D 2 No Vis. Bottom 7 very dense bed of just ruppia 235 -37.531867 149.789367 Zostera 4 D 2 No Vis. Bottom 7 medium length 259 -37.550000 149.759717 Zostera 4 D 2 No Vis. Bottom 7 put in at fisheries point – from there to site 2 is all dense zostera – Mon 29/03/99 265 -37.531133 149.738783 Zostera 4 D 2 No Vis. Bottom 7 medium leaf length on zostera plants – heavy algal load 284 -37.523850 149.701183 Zostera 4 D 2 No Vis. Bottom 7 medium algal loading 287 -37.522400 149.708633 Zostera 4 D 2 No Vis. Bottom 7 medium algae – quite long plants 288 -37.522650 149.711317 Zostera 4 D 2 No Vis. Bottom 7 medium algae – quite long plants 291 -37.516867 149.719867 Zostera 4 D 2 No Vis. Bottom 7 Quite long plants – medium algae. Whole bay dominated by distinct patches Zostera/Ruppia – quite heavy algae 292 -37.517217 149.721833 Zostera 4 D 2 No Vis. Bottom 7 quite long plants – medium algae 296 -37.511433 149.712067 Zostera 4 D 2 No Vis. Bottom 7 quite long plants – heavy algae 300 -37.511417 149.698950 Zostera 4 D 2 No Vis. Bottom 7 medium to long plants – medium algae 301 -37.510850 149.695750 Zostera 4 D 2 No Vis. Bottom 7 medium length – quite clean 302 -37.509633 149.695283 Zostera 4 D 2 No Vis. Bottom 7 long plants – medium algal cover – some ruppia 304 -37.505083 149.703333 Zostera 4 D 2 No Vis. Bottom 7 long plants – medium algal cover 313 -37.503417 149.727233 Zostera 4 D 2 No Vis. Bottom 7 long plants 317 -37.495483 149.739800 Zostera 4 D 2 No Vis. Bottom 7 long 319 -37.495067 149.741550 Zostera 4 D 2 No Vis. Bottom 7 long 320 -37.497117 149.744617 Zostera 4 D 2 No Vis. Bottom 7 quite long and clean 322 -37.503267 149.748267 Zostera 4 D 2 No Vis. Bottom 7 quite long and clean 336 -37.527600 149.743433 Zostera 4 D 2 No Vis. Bottom 7 medium length and medium algae

Marine and Freshwater Resources Institute – Page A12 Seagrass Mapping of Victoria’s Minor Inlets

MALLACOOTA INLET continued 349 -37.553667 149.754000 Zostera 4 D 2 No Vis. Bottom 7 medium length, medium algal load - Tue 30/03/99 357 -37.523133 149.765417 Zostera 4 D 2 No Vis. Bottom 7 medium length and medium algae 361 -37.519433 149.773850 Zostera 4 D 2 No Vis. Bottom 7 medium length, heavy algae 370 -37.496950 149.773383 Zostera 4 D 2 No Vis. Bottom 7 medium length, heavy algae 373 -37.496000 149.776000 Zostera 4 D 2 No Vis. Bottom 7 heavy algae 376 -37.501450 149.781133 Zostera 4 D 2 No Vis. Bottom 7 in this bay are lots of gelatinous "balls" attached to grass - see specimen 378 -37.502783 149.785183 Zostera 4 D 2 No Vis. Bottom 7 ruppia also has the balls on it 384 -37.498483 149.795883 Zostera 4 D 2 No Vis. Bottom 7 water very clear 385 -37.496500 149.796967 Zostera 4 D 2 No Vis. Bottom 7 clear water - plants quite clean and medium length 263 -37.537300 149.743100 Zostera/Ruppia 7 D 2 No Vis. Bottom 7 mix of zostera & ruppia - covered in heavy algal growth 340 -37.519700 149.750467 Zostera/Ruppia 7 D 2 No Vis. Bottom 7 mix of the 2 species 348 -37.523167 149.759383 Zostera/Ruppia 7 D 2 No Vis. Bottom 7 ruppia in shallow water - medium algal load 363 -37.515450 149.775350 Zostera/Ruppia 7 D 2 No Vis. Bottom 7 ruppia inshore/zostera offshore - at ~1-1.5m ruppia gives way to zostera 393 -37.497200 149.800050 Zostera/Ruppia 7 D 2 No Vis. Bottom 7 ruppia is in shallow, then zostera further out 241 -37.536600 149.784283 Zostera 4 M 4 Mud 2 long 386 -37.493683 149.799450 Zostera 4 M 4 Mud 2 is ruppia in close to bank still? 392 -37.495917 149.800850 Zostera 4 M 4 Mud 2 quite short plants 335 -37.528783 149.740850 Zostera 4 M 4 Sand 5 fringing medium length grass 337 -37.524683 149.745250 Zostera 4 M 4 Sand 5 medium length and medium algae 212 -37.560950 149.767733 Zostera 4 M 4 Sand 1 medium length plants 217 -37.553867 149.773933 Zostera 4 M 4 Sand 1 medium length plants 268 -37.524300 149.728800 Zostera 4 M 4 Sand 1 is a little flatter here so can build on 269 -37.521350 149.728017 Zostera 4 M 4 Sand 1 is a little flatter here so can build on 270 -37.519967 149.725017 Zostera 4 M 4 Sand 1 grass comes a little further from the bank here - heavy algae growth 271 -37.519850 149.722850 Zostera 4 M 4 Sand 1 grass comes a little further from the bank here - heavy algae growth 272 -37.520533 149.721450 Zostera 4 M 4 Sand 1 grass all around this bay (edges) and off the point 273 -37.521417 149.719250 Zostera 4 M 4 Sand 1 narrow band along the bank again 276 -37.522583 149.715967 Zostera 4 M 4 Sand 1 along bank 277 -37.524800 149.712800 Zostera 4 M 4 Sand 1 along bank 278 -37.526667 149.708600 Zostera 4 M 4 Sand 1 along bank

Marine and Freshwater Resources Institute – Page A13 Seagrass Mapping of Victoria’s Minor Inlets

MALLACOOTA INLET continued 280 -37.527667 149.702483 Zostera 4 M 4 Sand 1 in this bay 293 -37.518317 149.724317 Zostera 4 M 4 Sand 1 quite long plants - medium algae 315 -37.501267 149.732167 Zostera 4 M 4 Sand 1 medium length - medium algae 321 -37.501883 149.748300 Zostera 4 M 4 Sand 1 short plants - some ruppia - quite clean 351 -37.544667 149.760850 Zostera 4 M 4 Sand 1 medium length - quite clean 323 -37.505267 149.746333 Zostera/Ruppia 7 M 4 Sand 1 quite clean and medium length 324 -37.507383 149.743617 Zostera/Ruppia 7 M 4 Sand 1 quite clean and medium length 396 -37.506517 149.801417 Zostera/Ruppia 7 M 4 Sand 1 the 2 species are mixed 285 -37.523850 149.703050 Zostera 4 M 4 No Vis. Bottom 7 heavy algal load 314 -37.502750 149.728317 Zostera 4 M 4 No Vis. Bottom 7 medium length 381 -37.500450 149.788000 Zostera 4 M 4 No Vis. Bottom 7 medium length, medium algae 209 -37.559900 149.761350 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 210 -37.560500 149.763333 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 patches of drift 219 -37.549000 149.772117 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 228 -37.543200 149.765300 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 243 -37.539333 149.783000 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 2 - 252 -37.547233 149.767833 No Vis. Bottom 2 No Vis. Bottom 10 No Vis. Bottom 7 - 316 -37.497000 149.737933 Zostera 4 S 8 Gravel/Sand 4 quite clean 326 -37.507350 149.739533 Zostera 4 S 8 Gravel/Sand 6 very short plants 389 -37.491333 149.807317 Zostera 4 S 8 Mud 2 very sparse and small plants 412 -37.528233 149.785067 Ruppia 5 S 8 Sand 1 " -shallow water 221 -37.549417 149.769500 Zostera 4 S 8 Sand 1 very short 225 -37.546000 149.764433 Zostera 4 S 8 Sand 1 short and shallow 226 -37.544833 149.763167 Zostera 4 S 8 Sand 1 short and shallow 249 -37.545883 149.775600 Zostera 4 S 8 Sand 1 very short leaves 305 -37.505283 149.707600 Zostera 4 S 8 Sand 1 very sparse grass and shallow 318 -37.495000 149.740067 Zostera 4 S 8 Sand 1 shallow water - short plants 350 -37.548017 149.760067 Zostera 4 S 8 Sand 1 small clumps of sparse - quite short

Marine and Freshwater Resources Institute – Page A14 Seagrass Mapping of Victoria’s Minor Inlets

APPENDIX 2 SUMMARY OF GROUND-TRUTHING SAMPLE POINTS RECORDED IN THE MINOR INLETS

Marine and Freshwater Resources Institute – Page A15 Seagrass Mapping of Victoria’s Minor Inlets

Appendix 2. Summary table of total numbers of ground-truthing sample points recorded in the minor inlets.

Classes Recorded No. of Points Anderson Inlet Macroalgae 8 No Visible Bottom 1 Spartina 3 Zostera 17

Shallow Inlet Bare 2 Macroalgae 4 Zostera 24

Sydenham Inlet Bare 3 Filamentous Algae 2 No Visible Bottom 4 Ruppia 1 Ruppia/Zostera 3 Macroalgae 4 Zostera 44

Tamboon Inlet Bare 6 Filamentous Algae 1 No Visible Bottom 4 Zostera 43

Wingan Inlet Bare 1 No Visible Bottom 4 Zostera 23

Mallacoota Inlet Bare 5 No Visible Bottom 6 Ruppia 20 Zostera 103 Zostera/Ruppia 16

Marine and Freshwater Resources Institute – Page A16 Seagrass Mapping of Victoria’s Minor Inlets

APPENDIX 3 SEAGRASS LAYER DOCUMENTATION

Marine and Freshwater Resources Institute – Page A17 Seagrass Mapping of Victoria’s Minor Inlets

Name: SEAGRASS25 Full Name: Eastern Minor Inlet Seagrass Distribution Spatial Extent: Anderson Inlet, Shallow Inlet, Sydenham Inlet, Tamboon Inlet, Wingan Inlet and Mallacoota Inlet Owner: Department of Natural Resources and Environment Custodian: NRE – Parks, Flora and Fauna Access: Unrestricted Map Input Scale: 1:25 000 Search Words: Seagrass, Estuary, Marine Habitat, Anderson Inlet, Shallow Inlet, Sydenham Inlet, Tamboon Inlet, Wingan Inlet and Mallacoota Inlet Abstract: This layer contains polygons defining the spatial extent, species distribution and density of seagrass meadows within Victoria’s minor inlets east of Western Port.

Application of Layer: General: SEAGRASS25 is a 1:25,000 layer which represents spatial extent, species distribution and density of seagrass meadows within Victoria’s minor inlets east of Western Port. This layer is the result of a baseline survey of seagrass within Victoria. Ecological research into the health of seagrass meadows requires the type of detailed information collected in this baseline survey.

Layer Design Summary: Current Layer Design Considerations: This information represents a “snap-shot” in time of the spatial extent of seagrass meadows in Victoria’s minor inlets east of Western Port. The area of coverage and density of the various species of seagrass changes with time, both seasonally and yearly.

Future Layer Design Considerations: Future design considerations may include the adding extra species and recording the condition of the seagrass in relation to epiphyte coverage.

Summary of Relationship to other Layers: The landward boundary of the layer corresponds to the 1:25,000 coastline. The coastline is subject to change especially in areas subject to erosion or mass movement of coastal sediments and at the entrance to the inlets.

Data Currency Information: Data Set Status: Complete

Data Collection: Collection Period:

Data Site: Minor Inlets Beginning Date: April 1999 Ending Date: June 1999 Update Frequency: Not Planned

Data Lineage and Quality: Data Set Origin: Originality: Primary

Marine and Freshwater Resources Institute – Page A18 Seagrass Mapping of Victoria’s Minor Inlets

Data Collection Method: Remotely Sensed - Aerial Photography Field Measurements

Data Set Source: 1:20,000 Colour Aerial Photography enlarged to a scale of 1:10,000 Photography flown on the 19th , 25th, 26th of April, 1999

Data Set Processing Details: The delineation of the seagrass meadows was conducted through Aerial Photograph Interpretation. The linework was digitized from stable base overlays plotted on 1:10,000 colour photo prints. Polygons were attributed with species and density from data collected at sample sites in the field.

Positional Accuracy: Precision: Horizontal accuracy of 5m to 10m. Vertical accuracy NA

Attribute Accuracy: Attributes have been verified by MAFRI.

Completeness: Layer is complete for Victoria’s minor inlets east of Western Port

Further Information: Authors/Collators: David Ball Penny Morris

Supporting Documentation:

Blake,S., Roob,R. and Patterson, E. (2000) Victorian Marine Habitat Database – Seagrass Minor Inlets of Victoria, Marine and Freshwater Resources Institute report to Parks, Flora and Fauna Division.

Administration:

Documentation Details: Documenter: David Ball Address: MAFRI, Weeroona Parade, Queenscliff 3225 Position Senior Environmental Scientist

Marine and Freshwater Resources Institute – Page A19 Seagrass Mapping of Victoria’s Minor Inlets

SEAGRASS25 Polygon Attribute Table

Item Full Coln Item Name Item Out Item Item Notes Name Width Width Type Dec. 17 Seagrass25# 4 5 B - 21 Seagrass25-id 4 5 B - Seagrass 25 Class 3 3 I 0 Classification code for Classification seagrass categories. Links to seagrass categories LUT.

Seagrass Categories LUT

Class Category 1 Sparse Ruppia/Zostera mix 2 Sparse Ruppia 3 Sparse Zostera 4 Medium Ruppia/Zostera mix 5 Medium Ruppia 6 Medium Zostera 7 Dense Ruppia/Zostera mix 8 Dense Ruppia 9 Dense Zostera 11 Sparse Ruppia/Zostera mix with epiphytic algae 12 Sparse Ruppia with epiphytic algae 13 Sparse Zostera with epiphytic algae 14 Medium Ruppia/Zostera mix with epiphytic algae 16 Medium Zostera with epiphytic algae 17 Dense Ruppia/Zostera mix with epiphytic algae 18 Dense Ruppia with epiphytic algae 19 Dense Zostera with epiphytic algae 20 Undefined subtidal vegetation 21 Sparse Posidonia 22 Medium Posidonia 23 Dense Posidonia 31 Sparse Halophila 32 Medium Halophila 33 Dense Halophila 35 Sparse Halophila with epiphytic algae 36 Medium Halophila with epiphytic algae 37 Dense Halophila with epiphytic algae 41 Sparse Zostera/Posidonia mix 43 Dense Zostera/Posidonia mix 51 Sparse Zostera/Halophila mix 53 Dense Zostera/Halophila mix 55 Sparse Zostera/Halophila mix with epiphytic algae 56 Medium Zostera/Halophila mix with epiphytic algae 57 Dense Zostera/Halophila mix with epiphytic algae 61 Sparse Posidonia/Halophila mix 71 Sparse Zostera/Posidonia/Halophila mix 98 No Visible Bottom 99 Bare Substrata 100 Land 101 Intertidal Vegetation 110 Amphibolis

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111 Sparse Amphibolis 112 Medium Amphibolis 113 Dense Amphibolis 114 Amphibolis with epiphytic algae 115 Sparse Amphibolis with epiphytic algae 116 Medium Amphibolis with epiphytic algae 117 Dense Amphibolis with epiphytic algae 118 Amphibolis/Zostera mix 119 Sparse Amphibolis/Zostera mix 120 Medium Amphibolis/Zostera mix 121 Dense Amphibolis/Zostera mix 122 Amphibolis/Zostera mix with epiphytic algae 123 Sparse Amphibolis/Zostera mix with epiphytic algae 124 Medium Amphibolis/Zostera mix with epiphytic algae 125 Dense Amphibolis/Zostera mix with epiphytic algae 200 Undefined Algae 201 Woody detritus with undefined algae 202 Woody detritus/Zostera mix with undefined algae

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Name: SEAGRASS25 – Field Work Full Name: Seagrass field work in the Eastern Minor Inlets Spatial Extent: Anderson Inlet, Shallow Inlet, Sydenham Inlet, Tamboon Inlet, Wingan Inlet and Mallacoota Inlet Owner: Department of Natural Resources and Environment Custodian: NRE – Parks, Flora and Fauna Access: Unrestricted Map Input Scale: 1:25 000 Search Words: Seagrass, Estuary, Marine Habitat, Anderson Inlet, Shallow Inlet, Sydenham Inlet, Tamboon Inlet, Wingan Inlet and Mallacoota Inlet Abstract: This database in MS Access format contains the results of field work undertaken within Victoria’s minor inlets east of Western Port. seagrass species, density, substrate and presence of algae were recorded at each site.

Application of Layer: General: SEAGRASS25 is a 1:25,000 layer which represents spatial extent, species distribution and density of seagrass meadows within Victoria’s minor inlets east of Western Port. This layer is the result of a baseline survey of seagrass within Victoria. Ecological research into the health of seagrass meadows requires the type of detailed information collected in this baseline survey.

Layer Design Summary: Current Layer Design Considerations: This information represents a “snap-shot” in time of the spatial extent of seagrass meadows in Victoria’s minor inlets east of Western Port. The area of coverage and density of the various species of seagrass changes with time, both seasonally and yearly.

Summary of Relationship to other Layers: The sample sites relate to polygons in the layer SEAGRASS25.

Data Currency Information: Data Set Status: Complete

Data Collection: Collection Period:

Data Site: Minor Inlets Beginning Date: March 1999 Ending Date: March 1999 Update Frequency: Not Planned

Data Lineage and Quality: Data Set Origin: Originality: Primary Data Collection Method: Field Measurements

Data Set Source: Data was collected in the field by MAFRI scientists during March 1999.

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Data Set Processing Details: Data was collected using a differential GPS and observations at each site were recorded on field sheets. The locations and field observations were then entered into an MS Access database following completion of the field program.

Positional Accuracy: Precision: Horizontal accuracy of 5m to 10m. Vertical accuracy NA

Attribute Accuracy: Attributes have been verified by MAFRI.

Completeness: Layer is complete for Victoria’s minor inlets east of Western Port

Further Information: Authors/Collators: David Ball Penny Morris

Supporting Documentation:

Blake,S., Roob,R. and Patterson, E. (2000) Victorian Marine Habitat Database – Seagrass Minor Inlets of Victoria, Marine and Freshwater Resources Institute report to Parks, Flora and Fauna Division.

Administration:

Documentation Details: Documenter: David Ball Address: MAFRI, Weeroona Parade, Queenscliff 3225 Position Senior Environmental Scientist

SEAGRASS25 Field Work Table Attributes

Items recorded in the MS Access database are as follows:

Site No. Latitude Longitude Species Species Code Density Terrain Terrain Code Observations Date Observer

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APPENDIX 4 MINOR INLETS HISTORICAL AERIAL PHOTOGRAPHY

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Table A4.1: Details of historic aerial photography for the four study sites presented in the review of historic seagrass changes (Section 3).

Date Scale Type Project No. Run Roll Photo No. Assessment of photograph for seagrass interpretation

Shallow Inlet 28/11/72 1:25000 B/W 8120 10 2702 63 Good 13/01/81 1:32000 B/W 8120 8 3557 6 Good 07/02/87 1:20000 Colour 1902 2W 4080 23 Very good 03/01/91 1:25000 Colour 8120 10 4374 89 Good 18/04/93 1:10000 Colour 2127 19 4576 103 Very good -infra-red film 25/04/99 1:20000 Colour Minor Inlets - - 162 Very Good

Sydenham Inlet: Site 1 11/03/73 1:25000 B/W 8622 8 2771 52 Good 08/10/77 1:10000 B/W 1307 59 3210 190 Very good -wind ripples 03/03/82 1:25000 B/W 8622 8 3669 137 Very Good 04/11/86 1:10000 Colour 1717 4C 4048 99 Very good -wind ripples 30/01/87 1:40000 B/W 8622 5 4074 198 Very Good 17/03/90 1:40000 Colour 2033 22E 4333 37 Poor -close to high tide 26/04/99 1:20000 Colour Minor Inlets - - 212 Very Good

Sydenham Inlet: Site 2 15/01/86 1:20000 Colour 1804 4 3998 63 Very Good 30/01/87 1:40000 B/W 8622 5 4074 198 Good 17/03/90 1:40000 Colour 2033 22E 4333 37 Poor -close to high tide 26/04/99 1:20000 Colour Minor Inlets - - 212 Very Good

Mallacoota Inlet 07/04/69 1:12000 Colour 774 3 2284 4 Very Good 10/03/73 1:25000 Colour 8822 2 2765 35 Poor 08/10/77 1:10000 B/W 1307 64 3211 22 Good 04/11/86 1:10000 Colour 1717 18 4050 64 Very Good 08/03/90 1:25000 Colour 1995 81 4327 3 Very Good 1994 1:20000 Colour 2189 12E 4620 138 Good 26/04/99 1:20000 Colour Minor Inlets - - 212 Very Good

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Table A4.2: Additional historic aerial photography available for the four study sites reviewed in Section 3, but of insufficient clarity to be included in the assessment of historic seagrass changes.

Date Scale Type Project Run Roll No. Photo No. Assessment of photograph No. No. for seagrass interpretation

Shallow Inlet 17/01/80 1:50000 B/W 8120 2 3466 170 Poor 16/01/82 1:10000 Colour 1612 5 3621 33 Poor 1988 1:25000 Colour 1989 37 30A 15 Poor

Sydenham Inlet: Site 1 15/01/86 1:20000 Colour 1804 4 3998 63 Poor

Sydenham Inlet: Site 2 11/03/73 1:25000 B/W 8622 8 2771 52 Poor 03/03/82 1:25000 B/W 8622 8 3669 137 Poor 04/11/86 1:10000 Colour 1717 4D 4050 150 Poor 1994 1:20000 Colour 2189 20 4607 156 Poor

Mallacoota Inlet 07/03/61 B/W 488/8 2 1385 68 Poor 14/01/78 1:40000 B/W 8823 9A 3252 131 Poor 23/10/82 1:25000 B/W 8822 2 3698 51 Poor 13/05/83 1:20000 Colour 1687 3 3783 106 Poor 1987 1:40000 B/W 8822 1 4075 56 Poor 23/01/90 1:40000 Colour 2033 19 4315 154 Very good – scale too large to interpret seagrass

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Table A4.3: Assessment of historic aerial photography for potential study sites in the minor inlets. Sites could not be selected from this photography as there were either insufficient numbers of suitable photographs or the suitable photographs did not cover a wide enough time period. This list does not include photographs for the sites flown in 1999 as part of this study.

Date Scale Type Project Run Roll No. Photo No. Assessment of photograph No. No. for seagrass interpretation

Anderson Inlet – south of Inverloch (A range of good photos at this site but very little seagrass at this area in any of the years) 1950 B/W 875 8 932 44 Good 16/03/62 1:25000 B/W 434 1 1484 6 Good 03/11/68 1:16000 Colour 734 1 2217 45 Poor -murky water 07/01/70 1:12000 B/W 843 4 2344 131 Poor 1972 1:40000 B/W 8020 4 2046 46 Poor 24/12/73 1:30000 B/W 8020 3 8239 157 Poor 31/05/74 1:15840 Colour 1113 1 2900 8 Good 16/02/75 1:52000 B/W 8020 3 2964 207 Good 16/02/77 1:10000 B/W 1307 46 3176 149 Good 14/12/79 1:25000 B/W 8020 5 3459 186 Poor 30/12/81 1:10000 Colour 1613 5 3615 16 Good 08/09/85 1:25000 B/W 8020 4 3966 31 Poor 17/12/89 1:25000 Colour 1995 69 4300 130 Poor 10/01/91 1:25000 Colour 8020 5 4373 9 Good

Anderson Inlet – north of Venus Bay. 1950 B/W 875 8 932 39 Poor 16/03/62 1:25000 B/W 434 1 1484 2 Poor 03/11/68 1:16000 Colour 734 1 2217 41 Poor 07/01/70 1:12000 B/W 843 5 2344 101 Good 1972 1:40000 B/W 8020 4 2046 48 Good 24/12/73 1:30000 B/W 8020 3 8239 158 Fair 31/05/74 1:15840 Colour 1113 1 2900 5 Good 16/02/75 1:52000 B/W 8020 3 2964 207 Poor 14/12/79 1:25000 B/W 8020 5 3459 188 Poor 30/12/81 1:10000 Colour 1613 8 3615 55 Poor 08/09/85 1:25000 B/W 8020 4 3966 33 Poor 10/01/91 1:25000 Colour 8020 5 4373 11 Poor

Shallow Inlet – East 28/11/72 1:25000 B/W 8120 11 2702 15 Fair 13/01/81 1:32000 B/W 8120 9 3557 29 Fair 29/03/84 1:10000 Colour 1713 24 3862 68 Good 07/02/87 1:20000 Colour 1902 3 4080 27 Good 1988 1:25000 Colour 1989 37 30A 15 Fair 03/01/91 1:25000 Colour 8120 10 4374 89 Fair 18/04/93 1:10000 Colour 2127 19 4576 101 Good

Tamboon Inlet – South, near entrance. 07/03/61 B/W 490/8 9 1387 26 Poor 11/03/73 1:25000 Colour 8722 8 2777 7 Poor 08/10/77 1:10000 B/W 1307 59 3210 203 Poor 15/09/82 1:25000 B/W 8722 8 3686 7 Poor 13/05/83 1:20000 Colour 1687 5 3783 2 Poor 15/01/86 1:20000 Colour 1804 4 3998 56 Fair 04/11/86 1:10000 Colour 1717 6 4050 132 Fair 30/01/87 1:40000 B/W 8722 5 4074 201 Poor 03/03/90 1:40000 Colour 2033 22 4325 131 Poor 1994 1:20000 Colour 2189 20 4607 163 Poor

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Table A4.3: continued.

Tamboon Inlet – West 07/03/61 B/W 490/8 9 1387 26 Poor 11/03/73 1:25000 Colour 8722 7 2765 118 Poor 15/09/82 1:25000 B/W 8722 8 3686 7 Poor 13/05/83 1:20000 Colour 1687 6 3783 206 Poor 15/01/86 1:20000 Colour 1804 4 3998 56 Fair 04/11/86 1:10000 Colour 1717 6 4050 130 Fair 30/01/87 1:40000 B/W 8722 5 4074 201 Poor 03/03/90 1:40000 Colour 2033 22 4325 131 Poor 1994 1:20000 Colour 2189 19W 4613 221 Poor

Wingan Inlet - South 07/03/61 B/W 488/8 8 1386 144 Poor 07/04/69 1:12000 Colour 774 1 2284 54 Good 11/03/73 1:25000 Colour 8722 7 2765 103 Poor 08/10/77 1:10000 B/W 1307 62 3210 245 Poor 13/05/83 1:20000 Colour 1687 1 3783 140 Poor 04/11/86 1:10000 Colour 1717 9 4048 146 Poor 30/01/87 1:40000 B/W 8722 4 4074 147 Poor 03/03/90 1:40000 Colour 2033 22 4325 142 Poor 1994 1:20000 Colour 2189 19E 4614 14 Poor

Wingan Inlet - North 07/03/61 B/W 488/8 8 1386 144 Poor 07/04/69 1:12000 Colour 774 1 2284 54 Poor 11/03/73 1:25000 Colour 8722 7 2765 103 Poor 08/10/77 1:10000 B/W 1307 63 3211 100 Poor 13/05/83 1:20000 Colour 1687 1 3783 140 Poor 04/11/86 1:10000 Colour 1717 10 4050 4 Poor 30/01/87 1:40000 B/W 8722 4 4074 147 Poor 03/03/90 1:40000 Colour 2033 22 4325 142 Poor 1994 1:20000 Colour 2189 19E 4614 14 Poor

Mallacoota Inlet – Baker Bight 07/03/61 B/W 488/8 2 1385 68 Poor 10/03/73 1:25000 Colour 8822 1 2765 58 Poor 14/0/78 1:40000 B/W 8823 9A 3252 131 Poor 03/03/82 1:25000 B/W 8822 1 3656 195 Poor 13/05/83 1:20000 Colour 1687 4 3783 42 Poor 04/11/86 1:10000 Colour 1717 16 4050 112 Poor 1987 1:40000 B/W 8822 1 4075 56 Poor 23/01/90 1:40000 Colour 2033 18 4315 143 Poor 08/03/90 1:25000 Colour 1995 81 4327 5 Poor 1994 1:20000 Colour 2189 11E 4620 119 Poor

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