Anderson Inlet Fish Habitats 2010

Julia Kent and Patrick Coutin (Editors)

July 2011

Fisheries Victoria Assessment Report Series No 63

Anderson Inlet Fish Habitats 2010

If you would like to receive this Editor Contact Details: Julia Kent, Fisheries Victoria information/publication in an PO Box 114, Queenscliff Vic 3223 accessible format (such as large Authorised by the Victorian Government, print or audio) please call the 1 Spring Street, Melbourne Customer Service Centre on: Printed by Fisheries Victoria, Victoria 136 186, TTY: 1800 122 969, Published by the Department of Primary or email Industries. [email protected] Copies are available from the website: © The State of Victoria, Department of Primary www.dpi.vic.gov.au/fishing Industries, 2011. General disclaimer This publication is copyright. No part may be This publication may be of assistance to you but reproduced by any process except in accordance the State of Victoria and its employees do not with the provisions of the Copyright Act 1968. guarantee that the publication is without flaw of any kind or is wholly appropriate for your Preferred way to cite this publication: particular purposes and therefore disclaims all Kent, J. and Coutin, P.C. (Eds.) (2011) Anderson liability for any error, loss or other consequence Inlet Fish Habitats 2010. Compiled by the Fish which may arise from you relying on any Habitat Assessment Group. Fisheries Victoria information in this publication. Assessment Report Series. Report No. 63, 19 pp. (Primary Industries Research Victoria, Queenscliff). ISSN 1329‐7287 ISBN 978‐1‐74264‐863‐7 (print)

Anderson Inlet Fish Habitats 2010 ii Table of Contents

Executive Summary...... 1

Introduction...... 2

Goals, Objectives and Strategies for Maintenance of Fish Habitats ...... 3 Strategic Directions ...... 3 Strategic goal ...... 3 Strategic objectives...... 3 Strategic activities ...... 3 Policy and Legislative Context ...... 3

2001 Assessment ...... 4

2004 Assessment ...... 5

The 2010 Assessment ...... 6 Aims and Methods ...... 6 Aim, Objectives and Strategies of the Assessment...... 6 Boundaries of Anderson Inlet ...... 6 Definition of a Fish Habitat ...... 6 Methods...... 6

Research Outcomes ...... 7

Key Fish Species and Their Habitat Requirements ...... 8 Fish Species in Anderson Inlet ...... 8 Key Fishery Species and Habitat Links...... 8 King George whiting...... 8 Sand flathead...... 8 Estuary perch...... 9 Sand worms ...... 9 Bass yabbies...... 9 Important Fisheries Habitat...... 9

Status of Important Fish Habitats...... 11 Pelagic habitat ...... 11

Anderson Inlet Fish Habitats 2010 iii Seagrass ...... 11 Rocky habitats...... 11 Large woody debris ...... 11 Threats...... 11 Spartina...... 12 Climate change ...... 12 Management Implications...... 12 Spartina...... 12 Climate change ...... 13 Research Priorities ...... 13

2010 Assessment – Summary ...... 14 Status ...... 14 Research Priorities ...... 14

Acknowledgements ...... 15

References ...... 16

Glossary...... 18

List of Tables Table 1. Recreational fish species listed in Anderson Inlet ranked by angler catches...... 8 Table 2. ‘Icon’ species for Anderson Inlet...... 8 Table 3. Habitat requirements for each life stage of key targeted fish species in Anderson Inlet...... 10

Anderson Inlet Fish Habitats 2010 iv Executive Summary

The sustainable harvest of fishery resources is Most of the threats listed in the previous dependent on maintaining the integrity of the assessment (e.g. increased sediment and nutrient habitats, environmental conditions and loads) were no longer evident in Anderson Inlet ecological processes that support production of as a result of drought conditions in Victoria target fish populations. Fisheries Victoria has during the past 13 years. The most serious established a formal Fish Habitat Assessment ecological threats to fish habitat in Anderson process to provide scientific information on the Inlet were considered to be the presence and identity and status of marine fish habitats. This spread of Spartina, and the risks associated with information is essential for facilitating protection climate change. of important fish habitat and thus the The 2010 HAG concluded that the threats may sustainability of fisheries resources. cause: Anderson Inlet is one of Victoria’s larger • Reduction in fish habitat, including seagrass estuaries and supports a regionally significant habitat recreational fishery for both local and visiting • Decreased availability of food anglers. • Changes in the distribution and abundance The third meeting of the Anderson Inlet Fish of some fish species. Habitat Assessment Group (HAG) occurred on It was recognised that whilst new research has 10 February 2010 at Inverloch. been conducted since the last assessment, the Participants reviewed the previous assessment current status of habitats in Anderson Inlet was and considered the findings of new research. uncertain. Participants reviewed the list of targeted species The following research priorities were based on creel surveys conducted in 2006/07. recommended: Two new target species were identified which • Determination of King George whiting had not been listed in the previous assessment. source of recruitment for Anderson Inlet, and The 2010 AI HAG examined the habitat research into movement patterns of juvenile requirements of each life‐cycle stage of ‘icon’ King George whiting between Victorian bays species in Anderson Inlet. The following critical and inlets habitat features were identified: • Establish environmental monitoring • Connectivity between habitats programs to compare with past data sets, • Water quality detect current environmental changes, and make future predictions about climate • Geomorphology change impacts. • Seagrass and seaweed • Riparian vegetation and large woody debris. New information relating to the current status of the following habitats in Anderson Inlet was reviewed: • Pelagic habitat • Seagrass • Rocky habitats • Large woody debris. The main threats to fish habitats in Anderson Inlet were identified, and the implications of these findings for fisheries management were discussed. Recommendations for future research and monitoring needs for fish habitats were agreed.

Anderson Inlet Fish Habitats 2010 1 Introduction

A fishery resource is dependent on maintaining • Determine processes threatening these fish the integrity of the habitats, environmental habitats conditions and ecological processes that support • Make recommendations on fish habitat production of target fish populations. research and monitoring needed to assist in Management of fisheries includes identification the management of fish habitats. and advocacy of management actions needed to Anderson Inlet, located in South Gippsland, protect and where possible enhance ecosystems Victoria, is an important area for recreational that support production of fishery resources. To fishing, as well as a popular tourist, holiday and do this it is necessary to know: retirement destination. A management plan was • The type, location and extent of habitat and implemented after it was declared a fisheries environmental conditions that are important reserve in July 2003 (DPI 2006), specifying the for production and/or survival of key target objectives, strategies and performance measures fish species within the system for managing fishing activities within the • The links between particular Anderson Inlet Fisheries Reserve. habitat/environment conditions and An assessment of the key fish habitats within production/survival of stocks of key target the inlet was undertaken to assist in defining species research directions and management actions • The current status and historical trends in needed to provide sustainable utilisation of fish the condition of key fish habitats resources. • The main threats (whether from fishing or This fish habitat assessment report is divided other non‐fishing human activities) to the into the following sections: integrity of each key fish habitat. • A summary of the goals, objectives and In 1995, Fisheries Victoria established a formal strategies in place to maintain fish habitats Fish Habitat Assessment process to provide • A summary of the outcomes of the previous scientific information on the location and status assessments (2001, 2004) of key marine and estuarine fish habitats as an • Details of the aims and objectives of the 2010 input to the development or review of fishery Anderson Inlet fish habitat assessment, and management arrangements. This process an explanation of the methods and involves the participation of stakeholder processes by which the assessment was representatives, scientists and fishery managers conducted in fish habitat assessment workshops, and the publication of workshop findings. • A summary of the outcomes of research that has been undertaken in Anderson Inlet since Information and advice provided by these fish the previous assessment habitat assessment groups (HAGs) complement • Review of the key fishery species in the inlet the matters and issues dealt with by formal and their habitat requirements stock assessment and fishery assessment processes, and informs the development or • Update on the status of important fish review of habitat protection objectives in Fishery habitats in Anderson Inlet and assessment Management Plans for specified waters. of the likely main threats to fish habitats in the inlet The objectives of the Fish Habitat Assessment • A summary of the assessment of fish Process are to: habitats in Anderson Inlet and the • Identify fish habitats in Victorian waters prioritising of research/monitoring projects that are important in supporting production required to improve future assessments of of key fishery target species fish habitats in the inlet. • Assess the current status of key fish habitats

Anderson Inlet Fish Habitats 2010 2 Goals, Objectives and Strategies for Maintenance of Fish Habitats

Strategic Directions There is increasing evidence worldwide that the Fisheries Victoria is currently reviewing its sustainable use of any fishery resource is position in relation to the ʹhabitat advocacyʹ dependent not only on controlling the direct debate and fish habitat management. impacts of fishing on fish stocks, but also on maintaining the integrity of the aquatic habitats, Policy and Legislative Context environmental conditions and ecological The Victorian Government and the Department processes that are crucial for the production and of Primary Industries are committed to applying survival of target fish species. This is particularly the principles of Ecologically Sustainable so in inshore marine, estuarine and inland waters Development (ESD) to fisheries management. that are facing increasing pressures from human These principles are: population growth and associated agricultural, industrial, urban and tourism development. • To provide for equity within and between generations in the use of natural resources Strategic directions on fish habitat assessment • To enhance individual and community well‐ relevant to the deliberations of Habitat being by following a path of economic Assessment Groups are as follows. development that provides optimum current Strategic goal benefits while safeguarding the resource use • To secure the future of Victorian fisheries by options of future generations advocating the protection and maintenance of • To protect biological diversity and maintain essential fish habitats. ecological processes and systems Strategic objectives • To adopt a precautionary principle, so that where there are threats of serious or • Identify critical fish habitats and threatening irreversible adverse effects on resources or processes in conjunction with stakeholders. habitat, lack of full scientific certainty should • Lead and facilitate the development of not be used as a reason for postponing management arrangements that maintain or measures to prevent resource depletion or enhance the productive capacity of key fish environmental degradation. habitats. The Fisheries Act 1995 recognises these principles Strategic activities by including the following stated objectives: • Commission focused habitat assessment, • To protect and conserve fisheries resources, monitoring and research programs. habitats and ecosystems including the • Establish partnership arrangements to maintenance of quality ecological processes influence the management of non‐fishery and genetic diversity threats to key fish habitats. • To provide for the management, development • Develop and implement fish habitat and use of Victoria’s fisheries, aquaculture restoration programs in priority waters. industries and associated biological resources • Establish a community based fish habitat in an efficient, effective and ecologically protection focus across Victoria. sustainable manner. • Identify funding opportunities for fish habitat The Fisheries Act 1995 also specifies that a Fishery improvement and cooperate with other Management Plan declared for a given fishery agencies in accessing these funds. must identify critical components of the • Review legislative and policy frameworks to ecosystem relevant to the fishery, current or support fish habitat protection. potential threats to those components, and existing or proposed measures to protect or maintain key fish habitats.

Anderson Inlet Fish Habitats 2010 3 2001 Assessment

The 2001 Fish Habitat Assessment for Anderson Anecdotal evidence suggested major Inlet described its fisheries, management degradation of fish habitats had occurred within agencies and key stakeholders (Nicholson and Anderson Inlet. However, aside from the Gunthorpe 2005). expansion of the invasive pest plant species Spartina, these changes could not be Thirty‐three species or families of fish were substantiated scientifically. identified as components of the recreational fisheries of Anderson Inlet. That assessment also The impact of the expansion of Spartina in identified 11 species or families of fish, Anderson Inlet on fish habitat and on the including major prey species that were targeted production of key fisheries resources was not by recreational fishers. known, but it was likely to be negative. Spartina was considered to be a major threat, The habitat affinities of each life stage of each with the potential to physically exclude fish targeted species were identified from a from a significant portion of the inlet, and to combination of scientific knowledge, and from change ecological processes that support the experience and knowledge of HAG production and/or survival of key fisheries participants. species. The 2001 HAG noted that: The HAG identified four research areas and one • The pelagic (water), seagrass, and monitoring program, as high priorities. These unvegetated sediment habitats were used were to: directly by most of the targeted species at • Obtain an ecological ‘snapshot’ illustrating various stages in their life cycles the habitat associations of key target fish • Several species also used the snags and species, ecological processes maintaining riparian vegetation (such as mangroves) as inlet health, and the biological processes foraging grounds and/or spawning sites that link fish to each habitat • Low profile reef was also thought to be • Undertake an integrated nutrient‐based important to some species. study, which determines: Likely major threats to the maintenance of these • Nutrient levels within the water column habitats were identified as: of Anderson Inlet • Increases in sediment deposition rates, • Nutrient loads within the in‐flowing particularly from catchment erosion streams and drains • Decreasing water quality associated with • Nutrient re‐cycling within the sediments sediment and nutrient inputs of Anderson Inlet during periods of • Introduction and spread of pest species, high flow and low flow particularly in particularly the cord grass Spartina relation to the Tarwin River • Physical disturbances from recreational • Quantify the rate of sedimentation occurring boating and foreshore development in Anderson Inlet and identify major contributing sediment loads • Unknown factors affecting seagrass distribution and density. • Undertake regular monitoring of seagrass coverage to determine natural dynamics and impacts on fish production.

Anderson Inlet Fish Habitats 2010 4 2004 Assessment

The 2004 Fish Habitat Assessment for Anderson The HAG focussed on the factors driving fish Inlet updated the status of Anderson Inlet production in Anderson Inlet, particularly habitats upon which fisheries resources are estuary perch, as this species is resident in the dependent, identified management actions, and inlet and depends throughout its life history on recommended future directions for habitat the quality of the estuarine environment. research. The 2004 assessment concluded that there was The 2004 HAG added five species and one family insufficient information, either scientific or of prey to those identified previously. Estuary anecdotal, to determine the extent to which perch (Macquaria colonorum) and King George estuary perch are dependent on any of the listed whiting (Sillaginodes punctatus) were identified as habitats for spawning or nursery activities. ‘icon’ species, which best represented the The HAG identified the following research recreational fishery in Anderson Inlet. A further priorities: three habitats used by estuary perch in Anderson Inlet were identified. • Determine which habitats are crucial for sustaining the production of estuary perch in No new information was available on changes to Anderson Inlet the aquatic habitats and environment in • Assess the role played by Spartina in the Anderson Inlet. The 2004 HAG noted that: production of ‘icon’ fish in Anderson Inlet • Estuary perch are found in all creeks entering • Identify the factors that link estuary perch to Anderson Inlet and are likely to be more the crucial habitats in Anderson Inlet. widespread throughout the inlet than previously thought • King George whiting are found throughout the inlet, particularly around the entrance of the inlet and from the mouth of the Tarwin River to Mahers Landing • It is not known which habitats are primarily responsible for sustaining fish production in Anderson Inlet. Likely major threats to the maintenance of fish habitats in Anderson Inlet were identified as: • Catchment land use and activities causing increased sedimentation in the Tarwin River and Anderson Inlet • Scouring of seagrass beds, and disturbance of fish from recreational fishing boats • Erosion of banks caused by wake from water‐ski boats and fishing access, resulting in sand movement and the smothering of seagrass • The spread of Spartina, which may result in trapped sediment and displaced fish species. These threats may cause reductions in habitat and food availability for fish species, decreases in fish production, and changes to fish communities. The management implication was that these threats have the potential to decrease the productivity and quality of Anderson Inlet’s recreational fishery.

Anderson Inlet Fish Habitats 2010 5 The 2010 Assessment

Aims and Methods Definition of a Fish Habitat For the purposes of this assessment a habitat Aim, Objectives and Strategies of the was defined as the broad physical structures, Assessment zones and biological communities that support fish. The emphasis of this report is on those Aim habitats, which support fish targeted by To provide scientific advice on the changes to recreational fishers and key prey species. fisheries habitats in Anderson Inlet and identify environmental threats to the sustainability of the Methods fisheries resources. Data A literature search was undertaken to provide Objectives new information on the critical habitats for fish • Identify habitats important to the fisheries in species in Anderson Inlet based on their life Anderson Inlet cycle, diet, movements, and distribution. • Review the literature, scientific data and Information was also obtained from published anecdotal information that are available on papers and reports, databases, and anecdotal the habitats in Anderson Inlet information from anglers in Anderson Inlet. • Assess the current state of fish habitats and Building on the previous assessments, the provide a risk assessment of the habitat participants reviewed the habitat linkages for threats to fisheries production key species in the inlet. • Provide advice on management options to reduce environmental impacts by improving water quality and fish habitats • Identify information gaps and provide advice on habitat monitoring and research needs to improve habitat management. Strategies • Identify the habitats used by key species in Anderson Inlet • Describe the conditions of critical habitat characteristics in Anderson Inlet • Review habitat linkages for key species. Boundaries of Anderson Inlet Anderson Inlet was declared a shipping port during 1913. The current seaward boundary of the Port of Anderson Inlet is a straight line between Pt. Smythe and Pt. Norman. For the purposes of this assessment the seaward extent of the Port boundary was accepted as the seaward extent of the Inlet. This area includes all waters of Anderson Inlet bounded by the high water mark. The upstream boundaries of the assessment area are the limits of tidal salt‐ water intrusion.

Anderson Inlet Fish Habitats 2010 6 Research Outcomes

One of the research priorities identified in the • Stable isotope signatures of estuary perch previous assessment included to determine varied with size and among sampling which habitats are crucial in sustaining estuary locations, and suggested fish may not move perch production in Anderson Inlet. widely throughout the Inlet for months at a time Seasonal habitat surveys were conducted in Anderson Inlet in November 2006, and in • Both seagrass and Spartina contributed February, May and August 2007 (Conron et al. significantly to the nutrition of estuary 2010). Seven different habitat types were perch sampled using a number of netting methods. A • The average contribution of seagrass was total of 48 species, 19 of which were of higher for adult fish and juvenile fish which recreational fishing value, were recorded. The fed exclusively on invertebrates, but majority were found in multiple locations contributions of Spartina were higher than and/or habitat types. for seagrass for juvenile estuary perch that fed exclusively on fish Estuary perch were the most commonly sampled species. The following observations • Depending on the mix of nutrition sources, were made: contributions of seagrass and Spartina to the nutrition of estuary perch (regardless of age) • Estuary perch were sampled year‐round, may be as high as 80% and 50% respectively. with highest numbers caught in August The study has demonstrated seagrass habitat is • Estuary perch were most commonly found crucial in driving estuary perch production in in the Tarwin River and in or next to Anderson Inlet. Given this importance, large‐ mangroves and the inlet channels scale change in seagrass cover will significantly • Small (< 150 mm) estuary perch were found affect Anderson Inlet’s fisheries production. almost exclusively in the middle to upper regions of the Tarwin River estuary. Larger Spartina is also a significant supplementary fish (> 200 mm) were common in the source of nutrition for estuary perch in estuaries and in the Inlet Anderson Inlet, and may to some extent offset the impacts of seagrass loss. • Some spatial structuring of sexes was evident in November and February. Stable isotopes are forms of common chemical elements that do not degrade (i.e. are not radioactive). Each plant type (e.g. seagrass, algae or Spartina) has a distinctive stable isotopic profile. When plant matter is consumed by an organism, the isotopic signals in the organism are altered in a predictable way. Analysis of the isotopic signals indicates which types of vegetation were initially consumed and the degree of reliance an organism has on one particular vegetation type. The diet of estuary perch has been examined using stable isotope analysis (Conron et al. 2010) to establish which habitats were sources of base nutrition for estuary perch in Anderson Inlet. The study produced the following research findings: • Estuary perch in Anderson Inlet fed on a mix of fish and invertebrate species

Anderson Inlet Fish Habitats 2010 7 Key Fish Species and Their Habitat Requirements

Fish Species in Anderson Inlet King George whiting The intertidal and subtidal seagrass in Anderson The 2010 HAG reviewed the list of targeted Inlet is a critical habitat for King George whiting. species compiled by the 2004 Assessment (Table Fish of approximately 15–20 mm in length settle 1) based on recreational catches of boat and out into shallow seagrass habitats after a long shoreline anglers recorded during creel surveys planktonic phase (Jenkins and May 1994). A conducted in 2007/08 (Conron et al. 2010) and small number of juvenile King George whiting fishing reports (www.fishvictoria.com). were caught over seagrass beds in a seasonal netting survey carried out in Anderson Inlet Table 1. Recreational fish species listed in during 2006/07 (Conron et al. 2010). Seagrass beds Anderson Inlet ranked by angler catches. also provide shelter from tidal currents and Common Name Species Habitat floods, protection from predators and a source of Flathead spp Platycephalus spp m, e food (Hindell et al. 2002). King George whiting Sillaginodes punctata m, e (mig) Australian salmon Arripis trutta m, e (mig) The epifauna in seagrass beds (Zostera muelleri Sand crab Ovalipes australiensis m and Heterozostera tasmanica) and adjacent sandy Silver trevally Pseudocaranx spp m, e (mig) areas are a vital part of the food chain that Yellow‐eye mullet Aldrichetta forsteri m, e (mig) Estuary perch Macquaria colonorum e, f sustains the productivity and growth of King Gummy shark Mustelus antarcticus m, e (mig) George whiting (Jenkins et al. 1996; Smith et al. Snapper Pagrus auratus m 2008). In Westernport and Corner Inlet, the ‘m’ indicates marine, ‘e’ indicates estuarine, ‘f’ indicates sources of nutrition have been determined from freshwater and ‘mig’ indicates migratory. stable isotopes, which showed that 30‐80% of the food ingested by King George whiting was The ‘icon’ species, which best represented the derived from seagrass (Nichols et al. 1985, recreational fishery in Anderson Inlet, recognised Longmore et al. 2002, Hindell et al. 2009). by the 2010 AIHAG were estuary perch (Macquaria colonorum), King George whiting Habitat suitability models have been developed (Sillaginodes punctata) and short‐finned eel for King George whiting in Port Phillip Bay (Anguilla australis) (Table 2). The ‘icon’ species (Morris and Ball 2006). included both resident and migrant species. Resident species such as estuary perch are reliant Sand flathead on fish habitats within the Inlet and its tributary It is likely that most of the flathead catch consists rivers and creeks all of their life. Migrant species of sand flathead, but yank flathead are also such as King George whiting and short‐finned found in Anderson Inlet (Conron et al. 2010). eel, utilise both coastal and inlet habitats at The diet of juvenile sand flathead has been different times in their life cycles. studied in Port Phillip Bay and in Western Port (Edgar and Shaw 1995; Officer and Parry 1996; Table 2. ‘Icon’ species for Anderson Inlet. Longmore et al. 2002). The benthic fauna in Common Name Species seagrass and sandy areas sustain the productivity Estuary perch Macquaria colonorum and growth of sand flathead (Jordan et al. 1998). King George whiting Sillaginodes punctata In Western Port, the sources of nutrition have Eel, shortfinned Anguilla australis been determined from stable isotopes, which showed that up to 17% of the food ingested was based on seagrass epiphytes and about 14% was Key Fishery Species and Habitat based on green algae (Longmore et al. 2002). Links The main prey of sand flathead in Port Phillip New information on the critical habitats for each Bay are crustaceans including : Decapods life stage of fish species in Anderson Inlet were (Halicarcinus, Macrobrachium, Callianassa, identified from the literature and recent research. Liticheira, Nectocarcinus); isopods (Cirolana, Zuzara, Serolis) and amphipods (Corophium,

Anderson Inlet Fish Habitats 2010 8 Paradexaminae, Paradiceroides, Photis, Byblis). Estuary perch 15‐20 cm fed on shrimp (31%), Other prey include polychaetes (Australonereis, amphipods (23%), mysids (22%), isopods (12%), Driloneris), cephalopods (Octopus), and small fish and fish (1%). Estuary perch 20–25 cm fed on (Nesogobius). shrimp (32%), crabs (16%), isopods (29%), mysids (8%), amphipods (7%), and fish (3%). Sand flathead are caught throughout Andersons Inlet from Mahers Landing (4 km east of Stable isotope analysis has shown that the Inverloch) to the mouth of the Tarwin, and nutrition of estuary perch is mostly derived from around the entrance of the inlet. seagrass (up to 80%), but Spartina also makes a significant contribution to the food chain Estuary perch (Conron et al. 2010). Recent research has provided information on the early life history, diet, age, growth and Sand worms movement of estuary perch. During the day, fish As a source of bait, sand worms are important to remain in deeper water or in areas with cover the recreational fisheries. This species constructs such as large woody debris, mangroves and over a U‐shaped hole 15 cm deep with two openings hanging trees. At night fish move extensively lined with sand grains and mucus. It feeds on throughout the river estuary (Douglas 2010). fine organic matter at the water sediment interface. In Anderson Inlet, estuary perch are found in all the rivers and creeks. Small fish are distributed Bass yabbies about 10 km upstream from the mouth of the As a prey species, and as a source of bait, Bass Tarwin River as far as Fish Creek. Their yabbies (Callianassa australiensis) are important to movements are influenced by tidal cycles and the recreational fisheries. they are often abundant at the mouth of the river at low tide. Females spawn between late October and early December and the larvae appear in the plankton Larval development and life history have been one month later. Juvenile Bass yabbies settle out described (Trinski et al. 2005). Backwaters with of the plankton and are found in large numbers aquatic plants are important nursery areas where in muddy sand habitats. post larvae and juveniles up to 5 cm are most abundant (McCarraher and McKenzie 1986). The Important Fisheries Habitat 1–3 year old juvenile fish move upstream to inhabit freshwater. The mature fish move Based on the information considered by the downstream from freshwater (2) to brackish HAG, the habitat requirements of key targeted water (12–18) during the spawning season. fish species in Anderson Inlet are summarised in Table 3. The pelagic (water), seagrass, and Estuary perch are predators that feed on fish and unvegetated sediment habitats are used directly crustaceans. The diet of estuary perch was by these species at various stages in their life examined using fish caught during sampling in cycles. Several species also use large woody 2006/07 (Conron et al. 2010). Diet varied with the debris and riparian vegetation (such as size of fish, but was dominated by small mangroves) as foraging grounds and/or crustaceans and less than 4% of the prey was fish. spawning sites. Low profile reef may also be The most important prey items were shrimps important to some species. Many species had (Palaemonidae and Mysidae). salinity preferences and will move throughout Juvenile estuary perch (< 10 cm) fed mostly on the Inlet to satisfy these specific requirements. mysids (79%). Estuary perch 10–15 cm fed on mysids (57%), shrimps (31%), and fish (3%).

Anderson Inlet Fish Habitats 2010 9 Table 3. Habitat requirements for each life stage of key targeted fish species in Anderson Inlet. 10 Anderson

Species Life cycle requirements Survival Productivity Critical habitats and ecological links

Estuary Lack of barriers between estuarine and For eggs and larvae, a salt wedge Estuary perch in Anderson Inlet feed through food Connectivity – natural flow between the flood perch freshwater reaches for spawning and and a lack of flooding in the months chains which are sustained by seagrass and plain, river, and estuary.

Inlet recruitment. before and during October may be Spartina. The contribution to nutrition could be as important for successful spawning. high as 80% for seagrass, and up to 50% for Seagrass – important contributor to nutrition

Spartina. Fish Water quality (dissolved oxygen, pH Physical structures ‐ riparian vegetation, deep and toxicants) in the rivers and the holes, reed beds, mangroves, over hanging trees

Habitats estuary influences the survival and and large woody debris in rivers and estuaries. development of the early life stages of fish and their prey. These habitats provide estuary perch with refuges from strong currents, avian predation, and shade,

which may provide camouflage when capturing 2010 prey. Riparian vegetation also contributes indirectly by providing shelter for prey species.

Sand Spawn in estuaries, coastal embayments Unvegetated habitats function as a The diet of sand flathead consists of small fish, Connectivity – tidal flow between the sea and Flathead and inshore shelf waters. Initial settlement nursery area for juvenile sand crustaceans, worms and cephalopods. These prey Anderson Inlet. occurs into subtidal unvegetated habitats. flathead, providing camouflage. are derived from food chains sustained by seagrass epiphytes and green algae. Primary production – seagrass epiphytes and green algae.

Unvegetated sediment ‐ sand flathead are generally found on sandy or muddy substrate.

King Seagrass is essential for larval settlement. Spawning does not occur within King George whiting have been found to obtain Connectivity – tidal flow between the sea and George Anderson Inlet. King George nutrition predominantly (80%) from food webs Anderson Inlet. whiting whiting are already post‐larvae which are derived from seagrass and epiphytes (approx. 15 – 20 mm length) when that live on seagrass.. Seagrass – critical habitat for larval settlement they arrive at bays and inlets. and contributor to nutrition

Physical structures ‐ Channels and water depth.

Status of Important Fish Habitats

Since 2004, new research and monitoring has found in the inlet. Only one area could be found been implemented and a variety of management in the Inlet proper where fronds were in good actions have helped to improve environmental condition (i.e. long and thick). The only other conditions in Anderson Inlet and the Tarwin area with a significant amount of seagrass was River. The 2010 HAG participants reviewed this within Screw Creek. information and provided anecdotal accounts of changes to some of the main habitat features. Rocky habitats There are small areas of intertidal rocky reefs Pelagic habitat near the entrance, which are periodically Sampling in November 2006 and February, May covered by the movement of sediments. The and August 2007 (Conron et al. 2010) provided 2010 HAG considered that there had been a loss water quality data on temperature, salinity, of these rocky habitats in recent years, but the dissolved oxygen and turbidity levels in amount of exposed rocks varied and was Anderson Inlet, the Tarwin River and Screw dependent on sand movements near the Creek. entrance. In 2006/07 surface salinities in the Inlet were Large woody debris around 36, except in August 2007 when they Trees that fall into the river or estuary are dropped to 22. Salinities in the lower regions of known to be important habitats for some fish, the Tarwin River were close to 30 due to low particularly estuary perch. Riparian vegetation freshwater inputs. These conditions may result is an important source of large woody debris. in the upstream movement of some species (Conron et al. 2010). The participants identified an important area of snag habitat in Anderson Inlet located 150 m Dissolved oxygen levels in the inlet were east of Point Smythe. It consists of coastal Ti tree variable over the 2006/07 sampling, and were and coast wattle that have fallen into the inlet. lowest (77.2 % saturation) in February (Conron This part of the inlet is highly dynamic with et al. 2010). Ph levels were close to 8 (Conron et sand erosion and deposition which cause the al. 2010). trees to fall into the water and become partly Information from the Victorian Water Resources buried. The snags are significant because they Data Warehouse (www.vicwaterdata.net) for provide a physical structure that stabilises the Anderson Inlet was used to review the condition sand and provides protection from wave action of the river reaches flowing into the Tarwin and floods. River and Anderson Inlet. Generally, the environmental condition of the inflowing rivers Threats was poor to moderate. The major threats to fish habitats identified in The 2010 HAG discussed the anecdotal reports the previous HAG were: that the top end of the Inlet around the Tarwin • Increased sediment loads River mouth was heavily silted and juvenile • Physical disturbances (particularly to estuary perch are often trapped in the shallow seagrass beds) caused by boating waters as the tide changed. The lack of floods • Erosion and smothering of seagrass and invasion by Spartina have enhanced the accumulation of silt in the Inlet and caused the • The spread of Spartina. channels to become more shallow and narrow. Increased sediment and nutrient loads have not Information presented to the HAG suggests that been an immediate threat in Anderson Inlet for a recent improvements in catchment and farm number of years as a result of drought management are likely to have a positive impact conditions in Victoria. They may become a on water quality in the future. pressing issue if high rainfall events occur in the future. Physical damage to fish habitats, namely Seagrass seagrass, remains an ongoing problem in During the 2006/07 habitat sampling (Conron et Anderson Inlet. Although there is currently a al. 2010), only very small areas of seagrass were

Anderson Inlet Fish Habitats 2010 11 lack of seagrass in the inlet, damaging what is In Port Phillip Bay the most pronounced left will have greater, more severe consequences. physical and chemical trends over ~30 years Since the last assessment there have been no were found to be linked to seasonal changes and further reports of excessive growth of algae, catchment discharges (Spooner et al. in press which has occurred in the past in Screw Creek 2011), both of which are likely to alter as a result and Pound Creek. In recent years, it was of climate change. The drought conditions in recognised that the drought and reduced river Victoria over the past 13 years have already flow into Anderson Inlet may have altered caused hypersalinity in Port Phillip Bay. nutrient inputs. The variation in river flow through climate change or water extraction, may Management Implications also threaten the natural processes of nutrient In relation to the threats described above and in re‐cycling in the inlet in the future. the 2004 Assessment, the 2010 HAG posed the It was recognised that the drought had reduced following questions: river flow and this may have reduced sediment • How do the threatening processes impact on inputs in recent years. The 2010 HAG the factors that link fish to habitat? participants recognised the potential for climate • Which, if any, of these processes are change to increase re‐mobilisation of sediments significantly decreasing fisheries production with higher sea levels, storm events and in Anderson Inlet? flooding. Spartina Spartina The re‐colonisation of Spartina in some areas of Spartina was found to be distributed mostly the inlet poses a significant threat to fish habitat around the edges of the inlet from Screw Creek by altering flows, reducing invertebrate fauna in to the Tarwin River and along the southern inter‐tidal areas, invading/displacing native shore to Townsend Bluff. The area of infestation species including seagrass beds, and promoting included mangroves, sand banks and inter tidal accumulation of sediment. The consequences of habitats. the ongoing spread of Spartina are primarily: Some areas that had been sprayed with • Reduction in fish habitat, including seagrass herbicides in the past were being recolonised, habitat but it was thought that there had been a • Decreased availability of food. reduction in the amount of Spartina in Anderson Inlet. The aerial spraying of herbicides has been an effective control for new shoot growth and Climate change dense patches. However, spraying is less There is growing evidence of increasing threats effective for older plants and impractical for to estuaries and the fish habitats from climate isolated plants in salt marsh and mangroves. change (Scubel and Hirschberg 1978; Sherwood Hand spraying or removal of plants may be 1988; Short and Neckles 1999; Poloczanska necessary for more effective control. 2006). It is likely that there will be increased As Spartina generally out‐competes seagrass, variability in environmental conditions in the ongoing spread is likely to result in a reduction future, which may have positive or negative in seagrass cover in the inlet. This may affect impacts on the fish and fisheries habitats in recruitment of King George whiting, as seagrass Anderson Inlet. A range of physical and is a crucial habitat for settlement. chemical changes are expected to occur, which may influence the distribution and abundance of The source of King George whiting to the marine organisms. fishery in Anderson Inlet is unknown at this stage. It is known that small post‐larvae are rare The south‐eastern region of Australia is in Corner Inlet, and it has been suggested that expected to experience the greatest level of this fishery is supported by a different spawning marine water warming in the southern source than Port Phillip Bay and Western Port hemisphere (Poloczanska et al. 2007); however, (Jenkins et al. 2000, Jenkins 2005). It is also there is a lack of information on the potential possible that recruitment of older juvenile King changes in Australian estuarine and coastal George whiting to the Corner Inlet fishery may embayments. be a result of fish immigrating from other waters.

Anderson Inlet Fish Habitats 2010 12 Otolith chemistry studies have shown that Reduced river flows may affect the recruitment juvenile King George whiting from Victoria’s of some species, as has been demonstrated for major fisheries and juvenile nursery areas have black bream (Jenkins et al. 2010). The different chemical signatures (Kemp and Hamer consequences of reduced flows include reduced 2010). Further otolith chemistry and genetic stratification, and increased salinity levels, studies on the King George whiting larval which some species will not be able to tolerate. dispersal phase are necessary determine the Drought conditions are also likely to result in spawning sources contributing to different reduced catchment discharge, which can mean fisheries across Victoria. reduced nutrient concentrations, and potentially Conron et al. (2010) found that Spartina may lower primary productivity and decreased contribute up to 50% of the base nutrition of survival of fish larvae. estuary perch in Anderson Inlet. Spartina Responsive management strategies will be therefore may not be a direct threat to the required for adaptation to emerging threats fishery at its current density and distribution. associated with climate change. Long‐term Climate change monitoring will assist in the detection of gradual How fisheries stocks will respond to changes in environmental changes and help inform environmental variables related to climate decisions. change is an important consideration. Increasing temperatures may mean that in time, the Research Priorities survival rate and the distributional range of The 2010 HAG recognised that whilst new some species are likely to change, and that the research has been conducted since the last outcomes will not necessarily be negative. assessment, the current status of habitats in Monitoring and research programs in Port Anderson Inlet was uncertain. Phillip Bay (both past and current), have In light of this, the following research priorities provided a large amount of environmental data were agreed: and therefore a greater understanding of the • Determination of King George whiting ecosystem to help guide management decisions spawning sources for Anderson Inlet, and (Spooner et al. in press 2011). research into movement patterns of juvenile The key issues associated with climate change King George whiting between Victorian are changes in: bays and inlets through otolith • Salinity microchemistry.

• Primary productivity • Establish environmental monitoring programs to compare with past data sets, • Water temperature detect current environmental changes, and • Wind speed and direction make future predictions about climate • UV radiation. change impacts.

Anderson Inlet Fish Habitats 2010 13 2010 Assessment – Summary

The 2010 HAG participants considered that the Status recreational fishery in Anderson Inlet was The observations of the 2010 HAG were in part generally in good shape, with the estuary perch based on research findings since the previous stock in good condition. assessment, and assumptions on impacts of known catchment activities made by the The 2010 HAG recognised that whilst new participating members of the HAG. research has been conducted since the last assessment, the current status of fish habitats in Building upon the 2004 assessment, the 2010 Anderson Inlet is uncertain. HAG focused on updating information on key habitats and life cycle requirements for fish Research Priorities species in Anderson Inlet. The 2010 HAG identified the following research Most of the threats listed in the previous priorities: assessment (e.g. increased sediment and • Determination of King George whiting nutrient loads) were no longer prominent in spawning sources for Anderson Inlet, and Anderson Inlet as a result of drought conditions research into movement patterns of juvenile in Victoria during the past 13 years. The most King George whiting between Victorian serious ecological threats to fish habitat in bays and inlets through otolith Anderson Inlet were considered to be the microchemistry. presence and spread of Spartina, and the risks • Establish environmental monitoring associated with climate change. programs to compare with past data sets, The 2010 HAG concluded that the threats may detect current environmental changes, and cause: make future predictions about climate • Reduction in fish habitat, including seagrass change impacts. habitat

• Decreased availability of food. • Changes in the distribution and abundance of some fish species.

Anderson Inlet Fish Habitats 2010 14 Acknowledgements

This report was prepared by the Fish Habitat Max Fletcher – VRFish Assessment Group from discussions and a Rebecca Jol (Fisheries Victoria) compilation of contributions by members of the group. Participants at the Anderson Inlet fish June Lacock, President Anderson Inlet Angling habitat assessment workshop held on 10 Club February 2010 at Inverloch are listed as follows: Murray MacDonald (Fisheries Victoria) Matt Bowler (West Gippsland Catchment Ruth Tipping (Anderson Inlet Angling Club) Management Authority) Dick Brumley (Fisheries Victoria) Trent Tobias (Research Angler) Patrick Coutin (Fisheries Research Branch)

Anderson Inlet Fish Habitats 2010 15 References

Callinan RB, Fraser GC, Melville MD (1993) Hindell JS, Jenkins GP, Keough MJ (2002) Seasonally recurrent fish mortalities and Variability in the numbers of post‐settlement ulcerative disease outbreaks associated with King George whiting (Sillaginodes punctata) in acid sulphate soils in Australian estuaries. In relation to predation, habitat complexity and ʹSelected Papers of the Ho Chi Minh City artificial cage structure. Journal of Experimental Symposium on Acid Sulphate Soils. Publication Marine Biology and Ecology 268, 13‐31. 53ʺ, March 1992ʹ. (Eds DL Dent, MEF van Mensvoort) pp. 403‐410. (International Institute Hindell J, Ball D, Brady B, Hatton D (2009) for Land Reclamation and Improvement, The Assessment of estuarine water quality and its Netherlands). effects on seagrass health in Corner Inlet. Department of Primary Industries, Fisheries Conron S, Kent J, Hindell J (2010) Victoria Technical Report No. 46, Queenscliff. Implementation of the management plan for Anderson Inlet ‐ fishery and habitat research Jenkins GP (2005). The influence of climate on components. Department of Primary Industries, the fishery recruitment of a temperate seagrass‐ Recreational Fishing Grant Program Reserch associated fish, the King George whiting, Report No. 5/05/06/1, Victoria. Sillaginoides punctata. Marine Ecology‐Progress Series 288, 263‐271. DPI (2006) Anderson Inlet Fisheries Reserve Management Plan – 2006. Fisheries Victoria Jenkins GP, May HMA (1994) Variation in Management Report Series No. 28. settlement and larval duration of King George whiting, Sillaginodes punctata (Sillaginidae), in Douglas J (2010) Estuary perch movement and Swan Bay, Victoria, Australia. Bulletin of Marine habitat use in the Snowy River Fisheries Science 54, 281‐296. Victoria., Recreational Fishing Grant Program Research Report, Victoria. Jenkins GP, Wheatley MJ, Poore AGB (1996) Spatial variation in recruitment, growth and DSE (2009) Victorian Coastal Acid Sulphate Soils feeding of post–settlement King George whiting, Strategy. Department of Sustainability and Sillaginodes punctata, associated with seagrass Environment, Melbourne, Victoria. beds of Port Phillip Bay. Canadian Journal of Fisheries and Aquatic Sciences 53, 350–359. Edgar GJ, Shaw C (1995) The production and trophic ecology of shallow water fish Jenkins GP, Black KP and Hamer PA (2000). assemblages in southern Australia. II. Diets of Determination of spawning areas and larval fishes and trophic relationships between fishes advection pathways for King George whiting, in and benthos at Western Port, Victoria. Journal of southeastern Australia using otolith Experimental Marine Biology and Ecology 194, 83‐ microstructure and hydrodynamic modelling. I. 106. Victoria. Marine Ecology‐Progress Series 199, 231‐ 242. EPA (2009) Acid sulphate soil and rock. Environmental Protection Agency, Information Jenkins GP, Conron SD and Morison AK (2010). Bulletin No. 655.1. Highly varibale recruitment in an estuarine fish is determined by salinity stratification and Gobler CJ, Cullison LA, Koch F, Harder TM, freshwater flow: implications of a changing Krause JW (2005) Influence of freshwater flow, climate. Marine Ecology‐Progress Series 417, 249‐ ocean exchange, and seasonal cycles on 261. phytoplankton ‐ nutrient dynamics in a temporarily open estuary Estuarine, Coastal and Jordan AR, Mills DM, Ewing G, Lyle JM (1998) Shelf Science 65, 275‐288. Assessment of inshore habitats around Tasmania for life history stages of commercial

Anderson Inlet Fish Habitats 2010 16 finfish species. Tasmanian Aquaculture and Fisheries Instiutute, University of Tasmania, Poloczanska, E. S., R. C. Babcock, A. Butler, A. J. FRDC Final Report No. 94/037, Hobart. Hobday, O. Hoegh‐Guldberg, T. J. Kunz, R. Matear, D. A. Milton, T. A. Okey, A. J. Kemp J and Hamer P (2010). Otolith chemistry Richardson (2007). Climate change and as a tool to investigate population structure and Australian Marine Life. Oceanography and movement of King George whiting, Sillaginoides Marine Biology: An Annual Review. 45, 407‐478. punctata – a pilot study. Fisheries Victoria Research Report Series No. 48. Rampant P, Brown AJ, Croatto G (2003) Acid sulphate soil hazard maps : guidelines for Lin C, Melville MD (1993) Control of soil coastal Victoria. Department of Primary acidification by fluvial sedimentation in an Industries, CLPR Research Report No. 12, estuarine floodplain, eastern Australia. Victoria. Sedimentary Geology 85, 1‐13. Sammut J, White I, Melville MD (1996) Longmore AR, Nicholson GJ, Abbott B (2002) Acidification of an estuarine tributary in eastern Identifying habitats important to commercial Australia due to drainage of acid sulphate soils. fish in Western Port. Department of Primary Marine and Freshwater Research 47, 669‐684. Industries, Marine and Freshwater Resources Institute Internal Report No. 36, Queenscliff, Scubel JR, Hirschberg DJ (1978) Estuarine Victoria. graveyards, climate change and the importance of the estuarine environment. In ʹEstuarine McCarraher DB, McKenzie JA (1986) interactionsʹ. (Ed. ML Wiley) pp. 285‐303. (New Observations on the distribution, growth, York Academy Press. spawning and diet of estuary perch (Macquaria colonorum) in Victorian waters. Department of Sherwood JE (1988) The likely impact of climate Conservation, Forests and Lands, Fisheries change on southwest Victorian estuaries. In Division Technical Report No. 42, Melbourne. ʹGreenhouse : Planning for Climate Change ʹ. (Ed. GI Pearman) pp. 456‐472. (CSIRO Morris L, Ball D (2006) Habitat suitability Melbourne). modelling of economically important fish species with commercial fisheries data. ICES Short FT, Neckles HA (1999) The effects of Journal of Marine Science 63, 1590‐1603. global climate change on seagrasses. Aquatic Botany 63, 169‐196. Nichols PD, Klumpp DW, Johns RB (1985) A study of food chains in seagrass communities. 3. Smith TM, Hindell JS, Jenkins GP, Connolly RM Stable carbon isotope ratios. Australian Journal of (2008) Edge effects on fish associated with Marine and Freshwater Research 36, 683‐690. seagrass and sand patches. Marine Ecology Progress Series 359, 203‐213. Nicholson G, Gunthorpe L (2009) Anderson Inlet Fish Habitats 2004. Department of Primary Spooner, D. T, Walker, S. Acevedo, E, Morris, G. Industries, Fisheries Victoria Assessment Report Parry (in press: 2011) Port Phillip Bay Series No. 41. Environmental Data Review – Biophysical Assessment of Climate Change. Fisheries Officer RA, Parry GD (2000) Effects of season, Victoria Internal Report No 27, 137 pages. size, depth and time of day on diets of demersal Department of Primary Industries, Queenscliff, fish in Port Phillip Bay. Marine and Freshwater Victoria, Australia. Resources Institute, Queenscliff, Victoria.

Trnski T, Hay AC, Fielder DS (2005) Larval Poloczanska ES (2006) Impacts of climate change development of estuary perch (Macquaria on seagrasses. In ʹImpacts of climate change on colonorum) and Australian bass (M. Australian marine lifeʹ. (Eds AJ Hobday, TA novemaculeata) (Perciformes : Percichthyidae), Okey, ES Poloczanska, TJ Kunz, AJE and comments on their life history. Fishery Richardson) pp. 27‐35Canberra). Bulletin 103, 183‐194.

Anderson Inlet Fish Habitats 2010 17 Glossary

Algae: A large group of non vascular plants, compromising the ability of future many are microscopic, and live in water. generations to meet their own needs. Anoxic: Devoid of oxygen. Ecosystem: The physical, chemical and biological environment of a community of Anthropogenic: Changes resulting from human organisms, and all the interactions among activities. those organisms and between organisms Aquaculture: Farming of plants or animals in and their environment. water. Effluent: An outflow usually wastewater (eg Benthic: Belonging to the sea floor. sewage). Benthos: Organisms living on or in association Epiphyte: A plant growing on top of another with the sea floor. surface (e.g. crab shell, pier pylon, seagrass). Bioaccumulation: The concentration of substances (especially toxicants) in the Estuary: That area within the mouth of a river tissues of plants and animals. which is influenced by the sea. . Biota: All living organisms in a region. Eutrophication: An increase in the nutrient status of a water body, and consequently Bivalve: a type of mollusc possessing a two shell the rapid growth of plants, both natural valves joined by a hinge (eg scallops and and as a result of human activity. Excessive mussels). plant production may deplete oxygen and Bloom: Microalgae occurring in dense numbers suffocate animals. in a water body. Exotic species: Any species that is not of natural Catchment: The area of land from which run‐off origin to a location. from rain enters a waterway. Fauna: All kinds of animals. Chronic: Over a long period of time. Opposite Filter feeder: An animal that obtains food by of acute. filtering particles from water. Community: In the biological sense, a Fish: (a) live, fresh, imported or processed community is a group of plants and aquatic invertebrates with gills including animals that live together in a particular crustaceans, molluscs and all other forms of habitat. Often they are critically dependent aquatic life other than reptiles, amphibians on each other, with a loss of one species and mammals. leading to an impact on others. (b) Fish products or any part of the fish. Contaminant: A substance out of place (also Fishery: The taking of fish described by pollutants). reference to the species taken, the gear used Crustacean: Animals living in water which have and the purpose of the Fishery. a hard outer surface and jointed limbs and Fishery resources: The stock or stocks which belong to the class crusteacea. support the fishery. Demersal: Used for fish that live on or near the Flora: All kinds of plants. sea floor. Food chain: The sequence of consumption of Detritus: Non‐living organic matter (e.g. dead plants by animals and those animals by seagrass). other animals. Ecology: The study of living of organisms and Food web: A complex of food chains. their relationships to one another and the environment. Groundwater: The part of rainfall which seeps into the ground and moves slowly in a Ecologically sustainable development: The horizontal direction. management of resources to meet the needs of the present generation without Habitat: The place where a plant or animal lives.

Anderson Inlet Fish Habitats 2010 18 Heavy metals: A general term for cadmium, Seafood: The edible marine organisms. copper, iron, mercury, nickel, manganese, Seagrass: A group of flowering vascular plants lead, zinc, arsenic and selenium. which live in seawater. They take root in Hydrocarbons: Compounds of hydrogen and the sea floor. carbon such as petroleum. Sediment: The solid material that sinks to the Ichthyoplankton: Fish eggs and larvae which substrate. float in water. Sewage: Loosely applied to any waste sent to a Infauna: Animals living within the sediment on treatment plant. the sea bed. Stakeholder: An individual or organisation Inputs: Substances entering a water body. interested in and able to influence the management of (in this instance) Anderson Invertebrate: Animals without a backbone. Inlet and its fisheries. Larvae/Larval Fish: Early stage(s) of the life‐ Stormwater: Run‐off during storms. cycle of fish. Often fish drift in the upper layers of the water column with varying Substrate: A surface on which organisms live or degrees of swimming ability. into which they burrow. Macrophyte: A seaweed. Sustainability: A characteristic of a process or a state that can be maintained indefinitely. Microalgae: Single celled plants. Sustainable development: Improving the Mollusc: An invertebrate animal with a shell capacity to convert a constant level of (e.g. mussel) and belonging to the phylum physical resource use to the increased Mollusca. satisfaction of human needs. Nutrients: Substances required for plant growth Sustainable growth: A term applied only to (e.g. fertilisers). renewable resources. It means using them Organism: A living entity. at rates within their capacity for renewal. Organochlorines: Complex organic molecules Suspended matter: Particles suspended in with chlorine atoms attached (e.g. water. pesticides). Toxic: Poisonous. Pelagic: The water column. Toxicant: A poison. Phytoplankton: Microalgae that live in the Trophic: Related to food chains and food webs. water column. Turbidity: Cloudiness caused by sediments Plankton: Aquatic, free‐drifting suspended suspended in water. organisms, generally but not always microscopic. Wastewater: Water that has been used and discarded. Pollutant: A substance in excess or not belonging. Zooplankton: Small animals which live in the water column. Producer: An organism that can create living matter out of inorganic or inanimate matter. Productivity: The magnitude of a producer’s Glossary compiled from definitions activity. contained in Recreational use: The harvesting of fish or any Port Phillip Bay Environmental Study : Final other aquatic resource for personnel use. Report (Harris et al, 1996). Salinity: The salt content of the seawater. Port Phillip Bay Fisheries Management Plan: Background Paper (Fisheries Victoria, 1996

Anderson Inlet Fish Habitats 2010 19