Terrigal Lagoon Catchment Aquatic Survey Final Report (PDF File ...

Terrigal Lagoon 

Freshwater Aquatic 

Biodiversity Survey 2010 

Project 100056 

Sub Report 100056 - 2 

Robert B. McCormack 

31st July 2010 

© Australian Aquatic Biological Pty Ltd 2010


Freshwater Aquatic 

Biodiversity Survey 2010 

© Australian Aquatic Biological Pty Ltd, 

PO Box 3, Karuah, NSW, 2324 

Email Correspondence: info@aabio.com.au www.aabio.com.au 

Reference Project:100056 Aquatic Biodiversity Survey and Baseline Mapping 

of Freshwater Crayfish & Aquatic Species of the Gosford LGA - A Subset of the 

Australian Crayfish Project No.:100001 & Australian Aquatic Biodiversity Survey 

No.:100038 

About This Project. Australian Aquatic Biological Pty. Ltd. conducts aquatic research around 

Australia. Two of the major projects currently being conducted are Project No. 100001, the Australian 

Crayfish Project (ACP) & Project No. 100038, the Australian Aquatic Biodiversity Survey (AABS). 

The aims of these Projects are to survey the whole of Australia, to record and identify every species 

of freshwater fauna & their distributions. The present report embodies the findings for a subset of 

the ACP, Project No. 100056 Aquatic Biodiversity Survey and Baseline Mapping of Freshwater 

Crayfish & Aquatic Species of the Gosford LGA. Project 10056 is major sponsored by Gosford City 

Council under their Ecological Research Grants Program 2010. 

Disclaimer: 

Every effort has been taken to provide accurate information and taxonomic determinations, and to 

use names that are current at the time of report preparation. The Australian Aquatic Biological 

Company has exercised due care and skill in the preparation and compilation of the information and 

data set out in this publication. Notwithstanding, Australian Aquatic Biological, its employees and 

advisers disclaim all liability, including liability for negligence, for any loss, damage, injury, expense 

or cost incurred by any person as a result of accessing, using or relying upon any of the information 

or data set out in this publication to the maximum extent permitted by law. The authors accept no 

liability for errors and omissions. 

Preferred way to cite this publication: 

McCormack, R.B, 2010. Terrigal Lagoon, Aquatic Biological Survey 2010. Australian Aquatic 

Biological for Gosford City Council, Gosford NSW. 

Cover: Top: Terrigal Lagoon end of Pacific St. 

Bottom: Terrigal Lagoon Nature Reserve. 

Terrigal Lagoon Catchment Report Australian Aquatic Biological P/L 2

Report Summary 

Biological surveys were undertaken as part of both the broad Australian Crayfish Project 

(ACP) & Australian Aquatic Biological Survey (AABS) and a targeted sub-project on Gosford 

LGA (Project #100056, Australian Aquatic Biological 2010). The main sponsors for this 

project are Australian Aquatic Biological and Gosford City Council under their Ecological 

Research Grants Program 2010 that was assisting with biological research projects for 

the whole Gosford LGA. Surveys of the Gosford LGA are completed on a catchment/ 

drainage basis and Terrigal Lagoon is the second catchment surveyed completely as 

part of the broader Gosford LGA project. 

Terrigal Lagoon was surveyed in late May and early June 2010 and the findings are 

presented in this report. Surveys were conducted during flood conditions in May when 

all the ephemeral creeks were flowing and in early June when flow rates were greatly 

reduced. Unfortunately only a very small number of native fish species were recorded, 

as well as exotic Gambusia. No freshwater crayfish or crabs were found within the 

catchment. No freshwater snails or mussels were recorded from the catchment. Overall 

the aquatic biodiversity & population densities within the upper catchment were low. 

Generally, the catchment was in poor condition in this high population suburban and 

recreational area. Large areas of residential/rural land are included within the upper 

catchments but this land is mostly fully developed. Aquatic weeds, poor water quality 

and high nutrient loads were all recorded from the catchment. The full results of this 

aquatic biodiversity survey are presented in this report. 

Key words: Terrigal Lagoon, Gambusia, amphipod, gudgeon, milfoil, weeds, 

camboda. 

Figure 1. Terrigal Lagoon looking towards Ocean View Drive road bridge. 


Table of Contents 

Report Summary 3 

Table of Contents 4 

1. Background 6 

2. Introduction 6 

3. Aim of This Study 7 

4. Research Methods 8 

4.1. Methods 8 

5. Results & Discussion 13 

5.1. Crustaceans 13 

5.1.1. Freshwater Crayfish 13 

5.1.2. Euastacus Crayfish 13 

5.1.3. Gramastacus Crayfish 14 

5.1.4. Cherax Crayfish 14 

5.1.5. Atyidae Shrimp 14 

5.2. Fish Species 15 

5.2.1 Poeciliidae 15 

5.2.2 Pseudomugilidae 16 

5.2.3. Eleotridae 16 

5.2.4. Anguillidae 16 

5.3. Mollusca 17 

5.3.1. Hyriidae 17 

5.3.2. Planorbidae 17 

5.4. Insect Larvae 17 

5.5. Birds 17 

5.6. Site Results 18 

5.6.1. West Arm Survey Areas 18 

5.6.2. North Arm Survey Areas 25 

6. Field Notes 26 

7. Conclusion 29 

8. Recommendations 30 

9. Acknowledgements 31 

10. References 32 

List of Maps 

Map 1. Aerial Map of Terrigal Lagoon Catchment 10 

Map 2. Terrigal GPS Sites 11 

Map3. GPS Survey Sites 12 

List of Figures 

Figure 1. Terrigal Lagoon looking towards Ocean View Drive road bridge. 3 

Figure 2. From the Skillion looking towards Terrigal Lagoon entrance 9 

Figure 3. Atyidae Shrimp from the Lagoon proper. 14 

Figure 4. The Plague Minnow Gambusia holbrooki 15 

Figure 5. The Striped Gudgeon Gobiomorphus australis. 16 

Figure 6. Long Finned Eel. 16 

Figure 7. Reserve beside Norwich Place with abundant bird life. 17 

Figure 8. Royal Spoonbill foreground, White Faced Heron background 17 

Figure 9. Chestnut Teals 17 


Figure 10. Camboda caroliniana 18 

Figure 11. Camboda caroliniana 19 

Figure 12. Parrot Feather and weeds swept 

away and flat by recent rain. 20 

Figure 13. Parrots Feather or (Brazilian Water Milfoil) 

Myriophyllum aquaticum 20 

Figure 14. Purple stemed lilys washed flat in creek beside 

Bridge Coast Stadium 21 

Figure 15. Looks like Long leaf willow primrose 

in the stream bed beside Norwich Close 22 

Figure 16. Long-leaf willow primrose 23 

Figure 17. Long-leaf willow primrose Norwich Close 23 

Figure 18. The Creek between Sheffield Drive & Lindford Close 24 

Figure 19. Oily surfaces, seepage and iron bacteria. 24 

Figure 20. Lantana was common 25 

Figure 21. Lantana Flowers 25 

Figure 22. Trad or Wandering Jew 26 

Figure 23. Parrots Feather washed over weir in creek 

beside playing fields upstream of Charles Kay Drive. 27 

Figure 24. Purple Stemed Lillies, Parrots Feather & lantana 

line the banks along creek in Duffys Reserve. 31 

Figure 25. Striped Gudeons were one of the few native 

species present in the freshwater environments. 32 

List of Tables 

Table 1. Proposed Surveys Gosford LGA. 7 

Table 2. Aquatic Biological Survey Sites 27 

Appendix 

A. AABio Voucher Data Base - Terrigal 35 


1. Background 

The Gosford LGA is experiencing rapid growth and development. This high population 

coastal area represents a significant environmental asset that is fundamentally important 

to our lifestyle and economy. Implementing the infrastructure needed to support the 

increased population, agriculture and tourism must be undertaken so as to minimize or 

avoid ecological impacts on coastal vegetation, wetlands and threatened species. It is 

essential that management agencies have the information on hand to wisely plan the 

development and future of these fragile coastal regions. Additionally, Gosford LGA will 

be increasingly affected by global warming and climate change. Any decisions made 

today could have lasting effects on the biodiversity of this coastal area. Currently, 

however, management agencies do not have access to all the appropriate information 

to enable the protection of our coastal crustacean and fish species and their fragile 

aquatic habitats. 

Over the last few years the Australian Crayfish Project (ACP) & Australian Aquatic 

Biodiversity Survey (AABS) has been surveying eastern Australia for freshwater crayfish 

and aquatic fauna. These surveys have made numerous important discoveries. In addition 

to recording new knowledge and describing several new species of crayfish in the region, 

the survey has also revealed that an alarming proportion of the region’s endemic species 

appear to be facing serious threats. 

With the support of Gosford City Council the whole of the Gosford LGA will be surveyed 

on a catchment by catchment basis and the results collected will greatly increase the 

knowledge base and allow better management of these fragile coastal ecosystems and 

help the conservation of our aquatic species. 

2. Introduction 

Terrigal Lagoon is a small coastal lagoon located on the NSW Central Coast. It is a 

growing residential area located between the major towns of Gosford to the south and 

Wyong to the north. Being only 80 km or 85 minutes from the Sydney Central business 

district it is also a popular recreation area for both Sydney and local residents. 

The lagoon has a surface area of approximately 0.27 km 2 and a catchment area of 9.5 

km 2 . A large part of the upper catchment area of Terrigal Lagoon is rural land, most of 

which has been cleared. The lower slopes in the vicinity of the lagoon contain extensive 

urban development. South and west of the lagoon is the township of Terrigal. The 

northern part of the catchment includes part of the suburb of Wamberal. A large knoll 

of land rises from the centre of the catchment separating the two arms of the lagoon. 

The Terrigal Country Club and Golf Course are located at the limit of the North Arm. The 

North Arm of the creek drains an area of approximately 4.5 km² and the West Arm 3.7 

km². (Gosford Factsheet W10 (1/05)). 


Freshwater biological surveys were conducted in all the freshwater creeks and all inflow 

lines and drains. The main lagoon proper was generally not included in this survey. 

Note: The Gosford LGA for the purpose of AABio biological surveying is divided into 

grids. This Terrigal Lagoon catchment survey represents grids: 79 & 89. 

3. Aim of This Study 

The primary aim of Project No. 100056 is to determine what freshwater crayfish occur 

where in the Gosford LGA. Primarily freshwater crayfish are the priority and the Gosford 

LGA represents a significant area for crayfish distributions, yet little is known on the 

distributions of crayfish in this area. Prior to the start of this research project only two 

species have recorded distributions within the LGA; (Euastacus australasiensis & Euastacus 

spinifer) yet the extent of their distribution is unknown. Additionally, the area includes 

a number of coastal lagoons, lakes and streams all with independent catchments draining 

directly to the Tasman Sea that have been isolated from each other for millions of years 

and many containing unrecorded crayfish species. 

The project also records information on all the other aquatic fauna found in the LGA as 

well as information on landforms and vegetation. All this is in order to facilitate the 

better conservation and management of the aquatic ecosystems of the Gosford LGA. 

Note: For environmental and hygiene reasons (transfer of pests, diseases & weeds, etc.) 

each of the catchments are treated as individual systems and are surveyed separately 

with equipment and personnel being sterilized between catchments. A copy of our 

Hygiene Protocol and Code of Practice is available online at www.aabio.com.au 

Table 1. 

Proposed Catchment Surveys Gosford LGA 

PROJECT 100056 SURVEY LIST 

No Catchment Project No. Status Grid 

1 Wamberal Lagoon 100056-1 Completed 79, 80, 89, 90. 

2 Terrigal Lagoon 100056-2 Completed 79, 89. 

3 Avoca Lake 100056-3 In Prep 

4 Cockrone Lake 100056-4 In Prep 

5 Kincumber to Kilcare & Bouddi NP – 

Coastal Streams 

100056-5 Completed 87, 88, 97, 98, 

107, 108, 117 

& 118. 

6 Erina Creek 100056-6 In Prep 

7 Narara Creek 100056-7 

8 Brisbane Water –western side streams 100056-8 

9 Mullet Creek 100056-9 

10 Mooney Mooney Creek 100056-10 

11 Mangrove Creek 100056-11 


4. Research Methods 

A large proportion of Terrigal Lagoon catchment was surveyed (Map 1) to identify 

potential habitat areas. The survey was relatively unobtrusive and consisted of various 

methods: 

4.1. Methods 

Site co-ordinates and altitude were recorded using a Magellan Explorist 600 handheld 

GPS. Specimens were collected using a variety of methods to suit the conditions at each 

survey site. 

• Visual observation of crayfish presence/activity. Generally burrowing activity is 

the most common indication of crayfish in the area, although visual observation 

is also often a useful technique to record the presence of crayfish that are active 

on the forest floor or stream bed during sampling. 

• Visual search for shell fragments and remnants of crayfish or molluscs. Crayfish 

moult their shells to grow a new larger shell discarding the old shell, they lose 

claws due to fighting or claws are left from animal predation. Snail and mussel 

shells are often stranded as water recedes or carried onshore by predators. 

Searching for shell remnants can give a good indication of the species present, 

the numbers of animals in the population and an indication of the predators in 

the area feeding on the crayfish/molluscs as each predator has its own signature 

re shell remains. 

• Active netting. Scoop nets were used to scoop the bottom sediments, under logs, 

through leaf litter, under banks or through reedy sections, etc. This is a particularly 

important method to detect species that do not respond to baits or traps and 

particularly effective in muddy/turbid water. Three scoop nets were utilized: 

Small- 300 mm diameter hand held scoop. Medium- rectangular rake with 600 

mm x 200 mm opening. Large – 600 mm x 700 mm scoop net. 

• Cast Net. 3m diameter cast net. 

• Structure removal and probing. Crayfish & molluscs shelter under rocks and logs, 

etc. and time was allocated to lifting such shelter objects and searching by hand 

for fauna. This is another particularly important method to detect species that 

do not respond to traps or nets. 

• Burrow excavation by hand. Most crayfish species construct burrows, thus an 

integral part of the survey involved careful excavation of burrows by hand to 

search for crayfish. This is a particularly important method to detect species 

that do not respond to traps or nets. 

Most animals were examined at the collection site and released after identification. 

Some voucher material was retained where appropriate, and all retained specimens 

were placed in transport containers with a small amount of water and some vegetation 

from the site and returned to the laboratory. Selected specimens were placed in glass 


aquaria and photographed. Crustacean specimens were then euthanized by freezing for 

at least 24 hours and subsequently stored in clear, labelled specimen jars containing 70% 

ethanol. Tissue samples were retained in cell lysis buffer from selected specimens for 

subsequent DNA analysis, as part of the broader ACP. 

These simple methods were used to find and capture freshwater aquatic animals for 

identification in the Terrigal Lagoon Catchment. However, AABio employs a code of 

practice that is designed to limit the transfer of any pests and diseases from one 

catchment to another. For each catchment separate traps and nets are utilized and 

boots, etc. of field workers are sterilized between catchments. 

Use of traps in eastern drainages is prohibited under the Fisheries Management Act and 

all methods and collection was authorised under special scientific collection permits. 

All collections were authorised by the NSW Department of Industry and Investment 

under Scientific Collection Permit P05/0077-4.1. All collections were authorized by the 

National Parks and Wildlife Service, under Scientific Licence S13112. 

Figure 2. From the Skillion looking towards Terrigal Lagoon entrance 


Wamberal Lagoon 

Catchment 

Erina Creek 




MAP 1. 



Avoca Lake 



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151°25' 151°26' 151° 

-33°25' 

-33°26' 

-33°27' 

500 m 

MapSend Lite v.2.00e Beta (build 1303). Copyright © 2006 Thales Navigation, Inc. All rights reserved. 


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151°24' 151°25' 151°26' 151°27' 

-33°24' 

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1 km 

MapSend Lite v.2.00e Beta (build 1303). Copyright © 2006 Thales Navigation, Inc. All rights reserved. 


5. Results and Discussion 

Please note that results listed here reflect the species at that site at that time. Over 

time during different conditions different species or numbers may be present. 

5.1. Crustaceans 

5.1.1. Freshwater Crayfish. 

Prior to this research project only Euastacus australasiensis and Euastacus spinifer were 

recorded from the Gosford LGA, neither was known to occur within Terrigal Lagoon 

catchment and these two species were specifically searched for. Additionally, coastal 

habitats in NSW are known to contain two undescribed species of freshwater crayfish of 

genus Tenuibranchiurus and Gramastacus and these were also targeted. 

Survey No.:100056-1 of Wamberal Lagoon identified two species of crayfish in that 

catchment, an endemic species Gramastacus sp and an invasive introduced species 

Cherax destructor. Both these species were specifically searched for in Terrigal Lagoons 

catchment. 

Both Wyong LGA to the north and Gosford LGA to the south represent a significant 

freshwater crayfish distribution area. Though the knowledge base is small there seems 

to be a cut off line roughly running from Wamberal Lagoon, through Narara and then up 

through Central Mangrove that represents a species distribution line with one species 

(Euastacus spinifer) occurring on both sides, two species (Cherax setosus & Gramastacus 

sp) only north of the line and one species (Euastacus australasiensis) only south of the 

line. This project will map that line and the distribution of these crayfish species along 

the line, and the surrounding region. A scientific manuscript on those findings is proposed. 

No crayfish species at all were found within the Terrigal Lagoon Catchment. 

5.1.2. Euastacus Crayfish 

Despite our best efforts we were unable to confirm the presence of either E. spinifer or 

E. australasiensis. It would be our conclusion that the area is unsuitable for both species 

as the tributary creek system is too small and without sufficient highland catchment to 

support the clean, clear permanently flowing creek systems preferred by these species. 

West Arm drainage: The only site that may have been suitable was a small section of 

creek crossing Duffys Road (1POI032) but this was the only section of the creek suitable 

and would not be sufficient to support a sustainable population. 

North Arm drainage: The main stream feeding the north arm was sampled towards the 

start of the catchment in Beaufort Street (POI028), the creek was suitable for juvenile 

Euastacus crayfish but the available habitat area was too small to support a sustainable 


population (breeding adults). The creek was suffering from heavy sedimentation and 

weed with “wandering jew” (Tradescantia fluminernis) rampant along the stream edges. 

5.1.3. Gramastacus Crayfish 

No crayfish were collected within any of the catchment areas surveyed. No suitable 

habitat areas were found anywhere within the catchment. 

5.1.4. Cherax 

Yabbies (Cherax destructor) were not found within the catchment. This was a good sign 

and it is hoped that better education will keep them out. 

5.1.5. Atyidae 

Freshwater shrimp were not found within the upper catchment. This is considered a 

problem and a major area of concern. As they are the base food source for most native 

aquatic fauna the lack of this food source would seriously impact on other species like 

gudgeons, galaxias and blue-eyes, etc. 

A sample of the lagoon proper near the entrance (1WPT006) did record Atyidae shrimp 

so they are in the area, just not venturing upstream despite suitable looking habitat 

available. 

Figure 3. Atyidae shrimp from the Lagoon proper. 


5.2. Fish Species 

5.2.1. Poeciliidae 

Numbers of mosquito fish Gambusia holbrooki were captured at most sites and this 

species represents the main species with the widest distribution and largest biomass. 

Gambusia holbrooki are an introduced species that is a major pest and is having 

devastating repercussions on our native species. They are live bearers protecting their 

eggs and young and an exceptionally robust species, surviving in conditions that will kill 

most native species. They eat the eggs and larvae of our native species and survive in 

both fresh and marine environments. They are veracious feeders consuming the same 

food needed for our native species and often outcompeting our smaller native species. 

They are an exceptionally robust species surviving in water conditions that are unsuitable 

for our native species. 

Only small numbers of Gambusia were captured along the full length of all creeks from 

the lagoon to the upper most regions and from all drains with flowing water. Gambusia 

numbers were low with densities of 0-2 per cubic metre of water. The only area where 

numbers were high was around Duffy Park (West Arm drainage). 

Other pest and exotic fish species like swordtails, guppies, mollies, carp & goldfish were 

all absent from the catchment. Much of eastern NSW is impacted by these pest species 

and their absence in the catchment was fantastic news and very encouraging for the 

future health of the local environment and prosperity of the native aquatic fauna. 

Figure 4. The mosquito fish or plague minnow Gambusia holbrooki 


5.2.2. Pseudomugilidae 

Pacific blue-eyes (Pseudomugil signifier) were not found in the catchment. The only 

specimens collected were found within the lagoon close to the entrance (1WPT006). 

5.2.3. Eleotridae 

Striped gudgeon (Gobiomorphus australis) were captured in a tributary of west arm at 

the creek crossing at Duffys Road (1POI032) in the May scoop netting survey. At this 

specific site the creek was in relatively good condition with clear flowing water. Only 

one very large and very healthy gudgeon was captured in May but the follow up trap 

survey in June captured four smaller gudgeons and one Gambusia in a baited box trap. 

No other shrimp, crayfish or aquatic insects were in the water with these fish which was 

not a good sign. The creek on the other side of the road was in a more degraded state 

and produced zero specimens with no sign of aquatic life. 

Figure 5. The Striped gudgeon Gobiomorphus australis. 

5.2.4. Anguillidae 

Freshwater eels (Anguilla reinhardtii) were detected in the lower sections of stream 

around Duffys Park (1POI028, 1POI029, 1POI031). A total of three traps were destroyed by 

eels during our 24 hour trap survey. We did not use specific eel traps as eels are common 

in coastal drainages and are expected in all permanent water areas. The traps we used 

will not normally catch eels but do record their presence. 

Figure 6. Long finned eel. 


5.3. Mollusca 

5.3.1. Hyriidae 

Freshwater mussels were not identified from the Terrigal Lagoon catchment. Despite 

our best efforts we were unable to confirm the presence of any freshwater bivalves. We 

expect the small catchment and intermittent flow rates of feeder creeks are unsuitable 

for these species. 

5.3.2. Planorbidae 

Freshwater snails were not found within the upper catchments. This was surprising as 

suitable habits seemed common with cumbungi rampant in the area which they do 

prefer. 

5.4. Insect Larvae 

Mud-eyes, beetles and bugs were scattered throughout the catchment. 

5.5. Birds 

Birds were not a part of this survey, however, some of the species recorded will be listed 

here. Ducks of various species and dusky moorhens (Gallinula tenebrosa) were the common 

species in the catchment in only small numbers. 

The greatest concentration of birds was in the creek reserve beside Norwich Place, 

upstream of Duffys Park (west arm drainage). The main birds being wood ducks 

(Chenonetta jubata), chestnut teals (Anus castanea), dusky morhens (Gallinula tenebrosa), 

white faced herons (Ardea novaehollandiae) and royal spoonbills (Platalea regia). 

Fig. 9. Chestnut teals 

Fig. 8. Royal spoonbill 

Figure 7. Reserve beside Norwich Place with abundant bird life. 


5.6. Site Results 

Generally the catchment of Terrigal Lagoon was in a relatively poor state with large 

aquatic weed outbreaks. Terrigal Lagoon has two main feeder streams, defined as North 

Arm and West Arm. 

5.6.1. West Arm Survey areas 

Duffys Park, drainage line with artificial pond (site POI023). This pond was in a degraded 

state, litter, such as tables, wheelie bins and bottles were in the pond. Despite this the 

pond looked good with water lilies and birds utilizing the pond. Various ducks and 

moorhens were in and around the pond. Nutrient levels seemed high, indicated by 

filamentous algae and aquatic weeds. The weed needs positive identification as it looks 

like Cabomba caroliniana which is listed as one of Australia’s top 20 weeds “Noxious in 

category W4g” (this identification needs 

to be confirmed by an expert). 

Figure 10. Camboda caroliniana 

Cabomba caroliniana is a native of South 

America; this aquarium species will 

spread quickly and widely once 

introduced to the wild. It will spread by 

seed washed downstream or attached to 

the body or the feet of water birds. It 

will grow from broken pieces and it grows 

well in a high nutrient environment. The 

pond must be very suitable as it’s a large 

outbreak and very healthy growth. 

Because of this fast growth and rapid 

spread it is considered one of the worst 

weeds in Australia. Its invasiveness and 

potential for spread is a worry as it can 

choke waterways along the Central 

Coast. It grows quickly and can consume the water body with a mass of plant material 

made up of rotting leaves and stems that tend to attract algal growths and when a die 

back occurs the water goes rotten with oxygen crashes and aquatic conditions unsuitable 

for native species. 

It is important to identify these infection points and attempt to reduce or contain the 

outbreak. Because of its robust hardy nature this species is difficult to control but 

attempts need to be made, if this species spreads to drinking water supplies then dramatic 

economic consequences will ensue. 

Note: No native species were captured in the pond, just exotic mosquito fish Gambusia 

holbrooki. 


Figure 11. Camboda caroliniana 


Bridgecoast Stadium (1POI027) at the car park bridge crossing there are willows, parrot’s 

feather, cumbungi and duckweed. Well downstream at the weir, lots more milfoil, 

elephant ears, duckweed, azolla and cumbungi. 

POI024 One of the main West Arm feeder stream runs beside Bridgecoast Stadium on the 

southern side. This stream is also in a degraded state consisting of elephant ears (Colocasia 

sp), cumbungi (Typha sp) and an introduced weed parrot feather (Myriophyllum 

aquaticum). 

The purple elephant ear lilies or purple cunjevois (Colocasia esculenta) are not a native 

species and overseas are considered as an invasive species and generally will rapidly 

spread once introduced to wet areas. They have a dense tuber/rhizome (root) system 

that clogs the stream bed and during 

flood conditions these rhizomes can 

wash downstream spreading the infestation. 

They also have a large broad leaf 

that will grow thickly together shading 

out the native plants below. They are 

however, a pretty plant with value and 

sort by many as a home garden species. 

Figure 12. Parrot Feather and weeds swept 

away and flattened by recent rain. 

Cumbungi or bull-rush (Typha sp) is a 

native species and every effort needs 

to be made to encourage its growth as 

it will trap nutrients, and stabilize the 

stream bed providing habitat for native 

species. 

Figure 13. Parrot’s Feather or (Brazilian Water Milfoil) 

Myriophyllum aquaticum is a native of south America. It grows fast in nuitrient rich waters 

and forms dense stands that impede waterflow. 


Figure 14. Purple stemed lilies (Colocasia esculenta) washed flat in creek beside 

Bridgecoast Stadium 


The aquatic weed Parrot’s Feather (Myriophyllum aquaticum) is a concern. Also known 

as Brazilian Water Milfoil, this is a noxious weed. It is only spread by stem fragments as 

seed is not produced in Australia. 

Further down the stream are introduced Weeping Willows (Salix spp). There is concern 

about the spread of willows in NSW usually by pieces of branch being broken off and 

washing downstream or by the seeds produced. Willows grow big and strong in numbers 

that can divert waterways, they also have a huge thirst in summer consuming water 

supplies and their extensive root systems will invade drains and sewers creating damage. 

They do have aesthetic value and are popular in parks as they are good play trees for 

children. In small numbers they aren’t a problem but their spread is the concern and 

should be monitored. 

Willows are declared Weeds of National Significance (Salix spp). In New South Wales 

there is a regional declaration of willows as a Class 5 noxious weed. This provision 

prohibits the sale or planting of most Salix species. Landholders are not obliged to 

remove willows but it is illegal to plant or propagate them or for nurseries to sell them 

(Agriculture and Resource Management Council 2001). 

1POI027 at the car park bridge crossing there are willows, milfoil, cumbungi and duckweed. 

Well downstream at the weir you have lots more milfoil, elephant ears, duckweed, 

azolla and cumbungi. 

Note: No native species captured in this stream, just exotic Mosquito Fish Gambusia 

holbrooki. 

Further upstream around 

Sheffield Drive & Norwich 

Close the stream is heavily 

overgrown with cumbungi. 

Also in the stream around 

Norwich Close (1WPT011) is an 

outbreak of a species that 

appears to be Long-leaf 

willow primrose (Ludwigia 

longifolia). Identification by 

an expert is recommended as 

if Ludwigia longifolia then it’s 

a serious problem that needs 

attention. Note: No native 

species captured in this 

stream, just exotic Mosquito 

Fish Gambusia holbrooki. 

Figure 15. Looks like long leaf willow primrose 

in the stream bed beside Norwich Close 


Long-leaf willow primrose 

(Ludwigia longifolia) 

Willow-leaved primrose is a real nasty 

invasive aquatic weed, it produces 

thousands of tiny seeds in each of the 

capsules that follow the yellow flowers. It 

is a native of South America and introduced 

to Australia as an aquatic ornamental plant 

due to its pretty yellow flowers. 

Figure 16. Long-leaf willow primrose 

This is an erect annual shrub up to 3m high 

with a fibrous root system that loves shallow 

aquatic environments. Once established the thousands of seeds spreadout below or are 

washed downstream spreading the infestation. Floods uproot it and it will also propagate 

by stem fragments. 

This is a difficult weed to control and requires special attention. Ludwigia longifolia is 

declared a Class 3 or 4 noxious weed throughout some areas of NSW under the NSW 

Noxious Weeds Act 1993. Where it is a Class 3 noxious weed it must be fully and continuously 

suppressed and destroyed. Where it is a Class 4 noxious weed, its growth and spread 

must be controlled according to the measures specified in a management plan published 

by the local control authority. 

Ludwigia longifolia is also listed a class 5 noxious weed throughout nsw. As a notifiable 

weed, all outbreaks of Ludwigia longifolia must be reported to the local council within 

three days. The plant must not be sold, propagated or knowingly distributed. 

For further information, go to: http://www.dpi.nsw.gov.au/agriculture/pests-weeds/ 

weeds/profiles/ludwigia-longifolia 

Figure 17. Long-leaf willow primrose Norwich Close 


Figure 18. The creek between Sheffield Drive & Lindford Close 

Further upstream around Sheffield Drive (1WPT012) & Lindford Close (1WPT013) stream 

conditions had deteriorated considerably with brown seepage and oily surfaces along 

stream sides and brown iron slime coating all surfaces within the stream. No visible 

signs of aquatic life and sampling was not conducted. 

Figure 19. Oily surfaces, seepage and iron bacteria. 


1POI032 the most southern tributary of the Western Arm was sampled around the crossing 

at Duffys Road. Here the stream was well shaded with forest growth, tree ferns and 

some lantana. The creek was clear and flowing and without aquatic weeds in that 

section. Habitat was suitable for a range of native species, however, only one Stripped 

Gudgeon was captured. Upstream on the other side of the road the creek was in a more 

degraded state with paperbarks, eucalypts, ferns and cumbungi but water quality 

conditions were less favourable with brown slimy conditions. No aquatic life was seen 

or sampled on this side of the road. 

Figure 21. Lantana flowers 

Figure 20. Lantana was common 


5.6.2. Northern Arm Survey Areas 

POI014 Creek crossing High Valley Close. This Artificial creek/drain was just rock & mud, 

cutting through manicured lawns, with the stream edges sprayed, no aquatic weeds 

were in the stream. Only exotic Gambusia were captured in the stream. 

POI015 was a small flowing creek/drain with swamp oaks, palms, flowing drain, no 

shrimp or snails just a couple of Gambusia spotted but nothing captured. 

POI016 Drain, deep sediments, good cumbungi coverage, clear flowing, surrounded by 

lantana and she oaks. Note: No native species captured in this stream, just exotic 

mosquito fish Gambusia holbrooki. However, a gudgeon was spotted. 

POI026 was a non event, there was no stream as such, just manicured lawns with mown 

grass drainage lines and a large farm dam retaining the available flow. No specimens 

found. 

POI027 was sampled at the end of Beaufort Street. There the creek was no more than a 

drain in a rural/residential area. Ponds full of azolla and cumbungi were along the creek 

and camphor laurel trees (Cinnamomum camphora) were also growing along the creek 

edge. Camphor laurel leaves when dropped in water are toxic and their proliferation 

along watercourses could help to eliminate native fish and crayfish species. Note: No 

native species captured in this stream, just exotic mosquito fish Gambusia holbrooki. 

Additionally, it was noted that there was some sort of eucalyptus dieback occurring in 

the area. Whether this is natural or not is unknown. 

POI028 further upstream on Beaufort St, the creek system is small and ephemeral. It is 

heavily sedimented and infested with Wandering Jew (Tradescantia sp). Wandering jew 

is an introduced species and is well known and dreaded by dog owners as it’s known to 

cause an allergic reaction in dogs, both on the skin and more seriously in their mouth 

and throat. Wandering jew is an aggressive creeper that smothers native plants and 

forms a dense mat along 

riparian zones. No species were 

captured here. 

POI029 Creek crossing Brush 

Road, low swampy area, 

paperbarks and fern, cumbungi 

and flooded grasses. Nothing 

captured in scoop net survey. 

Figure 22. Trad or Wandering 

Jew Tradescantia sp was common 

along creek riparian zones 


6. Field Notes. 

Survey sites were recorded on a Magellan 600 GPS. Additionally, at each survey site a 

survey sheet was filled in which recorded the following: 

1. Date. 

2. Grid reference. 

3. Location-Street address. 

4. GSP location (digital Longitude & Latitude). 

5. Height. 

6. Time. 

7. Mileage. 

8. Habitat description. 

9. Land use. 

10. Water flow/clarity/condition, etc. 

11. Aquatic plants. 

12. Species/collection methods. 

The following is the survey site information brief. 

Table 2. 

Figure 23. Parrot’s Feather washed over weir in creek 

beside playing fields upstream of Charles Kay Drive. 


TABLE 2 Biological Survey Site DATA SHEET 

PROJECT 100056-2 TERRIGAL LAGOON CATCHMENT 

Creator /wpt/@lat /wpt/@lon Specimens Vegetation 

Height 

metres Name symbol 

MapSend Lite 

- 

33.42138 151.43405 11-1 Gambusia 2937 

Rock & Mud, Artificial creek/drain thru lawns, edges sprayed, no aquatic 

weeds. 13 POI014 

Crossed 

Square 

MapSend Lite 

- 

33.43335 151.438567 Flowing crk/drain looked good but nothing She Oaks, palms, flowing drain, no shrinp/snail/couple gambusia spotted 10 POI015 

Crossed 

Square 

MapSend Lite 

- 

33.43978 151.43365 12-1 Gambusia 2938 (spotted flat head type gudgeon) 

Drain, sediments, bullrush, clear flowing, surrounded lantana and she 

oaks 4 POI016 

Crossed 

Square 

MapSend Lite 

- 

33.43993 151.425467 2-2 Gambusia 2939 

Artificial pond in park, filamentous algae, water lillies, aquatic weeds 

Cabomba- noxious, nasturgium along banks. 15 POI023 

Crossed 

Square 

MapSend Lite 

- 

33.44147 151.42475 3-2 Gambusia 2940 

Elephant Ears, Cumbungi & Parrot Feather tyre in crk and willows 

downstream. 17 POI024 

Crossed 

Square 

MapSend Lite 

- 

33.44432 151.4255 4-2 Gudgeon 2941 clear flowing well shaded forest, and some lantana. 46 POI025 

Crossed 

Square 

MapSend Lite 

- 

33.43373 151.4167 NO Ck, lawns and farm dam No crk bed, manicured lawns, farm dam downstream 33 POI026 

Crossed 

Square 

MapSend Lite 

- 

33.43038 151.419683 5-2 Gambusia 2942 (Note eucalypt dieback) Azolla in pond, some cumbungi, nasturgiums 7 flooded grass 8 POI027 

Crossed 

Square 

MapSend Lite 

- 

33.43015 151.41525 NO-SIGN-poss further downstream, wandering dew Deep muddy sediments with covering wandering dew 23 POI028 

Crossed 

Square 

MapSend Lite 

- 

33.42365 151.425167 NO-just Gambusia Unsampled, just veiw roadside. 17 POI029 

Crossed 

Square 

MapSend Lite 

- 

33.44128 151.425217 NO-just Gambusia DUCKWEED-Cumbungi, milfoil, willows 3 1POI027 

Crossed 

Square 

MapSend Lite 

- 

33.44157 151.426433 T41-Opera house trap-eel attack trap Overgrown, lantana, eucalypts 2 1POI028 

Crossed 

Square 

MapSend Lite 

- 

33.44167 151.4263 T42-Opera house trap-eel attack trapl Overgrown, lantana, eucalypts 25 1POI029 

Crossed 

Square 

MapSend Lite 

- 

33.44152 151.426267 

4T3-Opera upstream-nothing/4T4-Opera downstream 

1x strip gudg, 1x gambusia, eel At weir Cumbungi/milfoil -grass, elephant ears, lantana 23 1POI031 

Crossed 

Square 

MapSend Lite 

- 

33.44415 151.4255 

5T1-B-4 stripped gudgeons spec 2986, 1x gambusia 

2987 Sheltered, eucalupts, lantana, tree ferns 13 1POI032 

Crossed 

Square 

MapSend Lite 

- 

33.44432 151.4255 5T2-B-nothing Sheltered, paper barks, eucalupts, lantana, tree ferns, wild rasberries 9 1POI033 

Crossed 

Square 

MapSend Lite 

- 

33.44154 151.441745 

Rake lagoon, blue eye, larvae, shrimp spec 2969, 2970, 

2971. Grassy banks, sandy bottom with flooded grass 5.46 1WPT006 

Crossed 

Square 

MapSend Lite 

- 

33.43848 151.436239 Rake below she oaks-nothing She oak forest, flooded grass and pine needle puddles 2.65 1WPT007 

Crossed 

Square 

MapSend Lite 

- 

33.43815 151.435563 Rake below she oaks-nothing She oak forest, flooded grass and pine needle puddles 4.97 1WPT008 

Crossed 

Square 

MapSend Lite 

- 

33.44138 151.420967 Sediment Gambusia spec2972, 2973 Grassy banks, sedimented bottom, cumbungi, azolla 15.43 1WPT009 

Crossed 

Square 

MapSend Lite 

- 

33.44162 151.420475 Odd gambusia Grassy banks, sedimented bottom, thick cumbungi, azolla 19.23 1WPT010 

Crossed 

Square 

MapSend Lite 

- 

33.44191 151.420034 few gambusia Grassy banks, pencil willow?/cumbungi/azolla in crk bed 19.2 1WPT011 

Crossed 

Square 


MapSend Lite 

MapSend Lite 

MapSend Lite 

MapSend Lite 

MapSend Lite 

MapSend Lite 

- 

33.44157 151.414832 Nothing Sheffield Drive-dirty-scary 23.25 1WPT012 

- 

33.44171 151.4147 Nithing Lindford place-open sewer-scary 24.19 1WPT013 

- 

33.44287 151.418562 Creek drain-Gambusia, spec 2974 Grass, trees, cunbungi, sandy bottom, brown scum 15.58 1WPT014 

- 

33.44327 151.41865 Imelda Ln-Swamp-nothing Soft Reed, deep sediments, azolla 18.07 1WPT015 

- 

33.44344 151.418166 Imelda Ln-Swamp-nothing Soft Reed, deep sediments, azolla 16.62 1WPT016 

- 

33.44259 151.415845 Drain-nothing Flooded grass, bare soil/clay 32.12 1WPT017 

Crossed 

Square 

Crossed 

Square 

Crossed 

Square 

Crossed 

Square 

Crossed 

Square 

Crossed 

Square 


7. Conclusion 

Terrigal Lagoon is a scenic coastal lagoon located within a high population suburban 

setting. Preliminary surveys of the Lagoon proper indicated a range of native species 

present. However, aquatic biological surveys of the catchment area indicate the 

biodiversity within the freshwater aquatic tributary system is extremely low with very 

few native species present and predominantly just exotic mosquito fish Gambusia 

holbrooki but even these were in relatively low numbers. This low fish population and 

biodiversity was reflected by the total absence of mollusc and crustacean species. 

High population areas generate increasing problems with people’s interpretation of 

what species are suitable in their backyards. Exotic invasive aquatic weeds were common 

in many parts of the upper catchments but most of these species are common home 

aquarium species or local garden species and would not be seen as a problem by many 

local residents. Additionally, because it’s a high population area we have all the usual 

catchment problems like, rural runoff, runoff from lawn and garden fertilizers, domestic 

animal wastes and septic seepage, etc. and indications of high nutrient and or low 

oxygen levels was a common theme in the catchment streams. 

This may well be an insurmountable problem as the tributary streams feeding into the 

Lagoon are very small with highly urbanized catchments; there just isn’t sufficient 

catchment or stream flow rates to adequately sustain and flush these short creeks 

systems. The small catchment size limits the capacity of the system to be self cleansing 

and this is amplified in drought conditions. Alternatively, in wet conditions the steams 

will rapidly flush and clean themselves but once the rain stops so does the flow. 

It would be predicted that the catchment streams flush and clean themselves rapidly 

during rain events then slowly deteriorate with increasing nutrient levels as dry weather 

and low rainfall conditions impact. This fluctuation creates unstable conditions not 

inducive to native species. 

Better education on native and exotic species and the dangers or releasing aquarium 

plants and animals could have long term benefits. General community awareness and 

education programs on the aquatic biodiversity of their local streams and what they 

can do to help would have massive benefits. A reoccurring undertone of poor community 

awareness was common throughout the area. I would be sampling creeks basically in 

people’s backyards or along the edge of walkways, etc. and as you see people you would 

say “g’day” and perhaps have a chat on what you’re doing, etc. The common response 

when you tell them “I’m doing a survey and looking for the fish and yabbies in the 

stream” is “You won’t find anything there!” Without fail the local residents considered 

their creeks as polluted and dead with nothing in them and when I would respond with 

“you’d be surprised there are some beautiful little native gudgeons living happily here” 

they are shocked. 


I cannot help but feel this lack of knowledge as to what is in their local creeks is not 

helping in keeping the creeks clean and supporting Councils ongoing initiatives to improve 

the catchment. 

8. Recommendations 

The pond in Duffys Park, with the Cabomba outbreak should be scheduled for draining in 

summer during a predicted dry spell. This could be easily and cheaply achieved by just 

pumping the pond out, sun drying will effectively kill the infestation together with a 

dash of herbicide on any damp areas that refuse to dry. 

My discussions with local residents in the area whilst conducting the surveys indicated 

a willingness by many to clean up their local creeks and riparian zones. Wamberal 

Lagoon directly north is a perfect example of what local volunteers can do to remediate 

the local environment. I would recommend that support and encouragement be given 

to promote local community bushcare groups to start a local cleanup. 

Ongoing efforts to reduce nutrient loads should continue and specifically nutrient loads 

within the creek system at the end of Lindford Close (1WPT013) should be investigated. 

Water quality & biodiversity monitoring of the freshwater catchment streams on an 

ongoing basis would also be recommended. To obtain significant information approx 10 

sites should be monitored for water quality and biodiversity twice per year (winter/ 

summer) on the same day and then over time, trends can be seen, etc. 

Gosford City Council has in place a Coastal Lagoon Management Plan that covers the 

Terrigal Lagoon and catchment. This comprehensive Plan covers most issues and should 

be promoted and supported to help improve the overall health and prosperity of the 

catchment systems. 

Figure 24. Purple Stemed Lilies, Parrot’s Feather & Lantana line the 

banks along creek in Duffys Reserve. 


9. Acknowledgements 

Unless otherwise referenced, information presented on Terrigal Lagoon NSW has arisen 

from recent biological surveys undertaken as part of the broader Australian Crayfish 

Project & Australian Aquatic Biological Survey and we are thankful to Australian Aquatic 

Biological Pty Ltd for sponsoring that work and for providing access to laboratory and 

field equipment. 

Sponsorship for the Terrigal Lagoon project was supported by Gosford City Council under 

the Ecological Research Grants Program 2010 and we are thankful to Gosford City Council 

and Michael Ebert, Environment Officer | Education and Compliance. 

Our thanks to Dr Stephen Keable, Collection Manager, Marine Invertebrates (Natural 

Science Collections) Australian Museum, for his help, support and assistance with making 

the Australia Museum collection available for study. Also Helen and Rodger for all the 

work I keep creating for them, I really do appreciate all your efforts, much thanks. 

Thanks to Janet Waterhouse, Australian Museum for assistance with the confirmation of 

identification of the freshwater snails in the Gosford LGA. 

We are thankful to Palm Grove Ourimbah Creek Landcare Inc. who assisted with weed 

identification. https://sites.google.com/site/palmgroveourimbahcreeklandcare/ 

All collections were authorized by the NSW Department of Industry and Investment 

under Scientific Collection Permit P05/0077-4.1. Special thanks to Bill Talbot (Director, 

Fisheries and Aquaculture) for organizing our permit. 

All collections were authorised by the National Parks and Wildlife Service, under Scientific 

Figure 25. Striped Gudeons were one of the few native species present in the freshwater 

Licence 

environments. 

S13112. 


10. References: 

Australian Crayfish Project, 2005 – 2010. Collection records c/- Australian Aquatic Biological 

Pty Ltd, Karuah NSW Australia. 

Gosford City Council, COASTAL LAGOONS MANAGEMENT PLAN, Wamberal, Terrigal, Avoca 

and Cockrone. Adopted July 1995 

McCormack, R.B., Horwitz, P. (in prep). Gramastacus n. sp. (Decapoda: Parastacidae): 

A new species of freshwater crayfish from coastal New South Wales, Australia. (Peerreviewed 

scientific journal article). 

McCormack, R.B., Horwitz, P., Coughran, J. (in prep). Conservation of Imperilled 

Crayfish – Gramastacus sp. nov. (decapoda: parastacidae), a lowland coastal crayfish 

from the central & mid north coast, New South Wales, Australia. (Peer-reviewed scientific 

journal article). 

McCormack, RB. 2008 “The Freshwater Crayfish of NSW Australia” Australian Aquatic 

Biological Pty Ltd., Karuah, NSW. ISBN 978-0-9805144-1-4 

Terrigal Lagoon, Factsheet W10(1/05), Gosford City Council, Natural Resources Unit, 9th 

Floor - Administration Building, 49 Mann Street (PO Box 21), GOSFORD NSW 2250. 

Weeds of National Significance, Weed Management Guide. CRC for Australian Weed 

Management and the Commonwealth Department of the Environment and Heritage. 

http://www.weeds.gov.au/publications/guidelines/wons/pubs/c-caroliniana.pdf 

© Australian Aquatic Biological Pty Ltd 2010 


This Report Prepared 

for 

Gosford City Council 

By 

Robert B McCormack 

……………………………………………………………………………….. 

31/07/2010 

……………………………………………. 

Research Director 

Australian Aquatic Biological Pty Ltd 

31 st July 2010 


APPENDIX 1 SPECIMEN COLLECTION DATA ‐ TERRIGAL CATCHMENT 

Collecti 

STATE or 

COLLECTION 

Family Genus Species Collector's ID Note Sex 

COUNTRY LOCALITY LATITUDE LONGITUDE ALTITUDE 

on ID # 

TERRITORY 

DATE 

COLLECTOR(S) Vouchered OTHER NOTES 

2937 Poeciliidae Gambusia holbrooki mosquito fish mix x 2 NSW Australia Crk xing High Valley Close, (Terrigal Lagoon Catchment) 33.42139 151.43405 13 26‐May‐2010 RB McCormack Yes scoop 

2938 Poeciliidae Gambusia holbrooki mosquito fish mix x 8 NSW Australia Crk xing Terrigal Drive, opposite Bellbird Ave, (Terrigal Lagoon Catchment) 33.43979 151.43365 4 26‐May‐2010 RB McCormack Yes scoop 

2939 Poeciliidae Gambusia holbrooki mosquito fish mix x 20 NSW Australia Pond, Duffy Park, Terrigal Drive, (Terrigal Lagoon Catchment) 33.43994 151.42547 15 27‐May‐2010 RB McCormack Yes scoop 

2939 Poeciliidae Gambusia holbrooki mosquito fish mix x 26 NSW Australia Creek beside Bridgecoast Stadium, (Terrigal Lagoon Catchment) 33.44146 151.42476 17 27‐May‐2010 RB McCormack Yes scoop 

2941 Eleotridae Gobiomorphus australis striped gudgeon mix x 1 NSW Australia Creek xing Duffy Road (Terrigal Lagoon Catchment) 33.44431 151.42550 46 27‐May‐2010 RB McCormack Yes rake 

2942 Poeciliidae Gambusia holbrooki mosquito fish mix x 6 NSW Australia Beaufort/Vicary Rd (Terrigal Lagoon Catchment) 33.43038 151.41968 8 27‐May‐2010 RB McCormack Yes rake 

2969 Atyidae Paratya australiensis shrimp 3 NSW Australia Terrigal Lagoon, End of Pacific St, Terrigal (Terrigal Lagoon Catchment) 33.44153 151.44175 0 9‐Jun‐2010 RB McCormack Yes rake 

2970 Psuedomugilidae Psuedomugil signifer pacific blue eye mix x 2 NSW Australia Terrigal Lagoon, End of Pacific St, Terrigal (Terrigal Lagoon Catchment) 33.44153 151.44175 0 9‐Jun‐2010 RB McCormack Yes rake 

2971 Fish larvae mix x 2 NSW Australia Terrigal Lagoon, End of Pacific St, Terrigal (Terrigal Lagoon Catchment) 33.44153 151.44175 0 9‐Jun‐2010 RB McCormack Yes rake 

2972 Poeciliidae Gambusia holbrooki mosquito fish mix x 8 NSW Australia Creek, end Norwich Close Terrigal (Terrigal Lagoon Catchment) 33.44138 151.42097 15 9‐Jun‐2010 RB McCormack Yes rake 

2973 mayfly 1 NSW Australia Creek, end Norwich Close Terrigal (Terrigal Lagoon Catchment) 33.44138 151.42097 15 9‐Jun‐2010 RB McCormack Yes rake 

2974 Poeciliidae Gambusia holbrooki mosquito fish mix x 4 NSW Australia Creek/drain beside King Ave, opp Imeda St, Terrigal (Terrigal Lagoon Catchment) 33.44287 151.41857 16 9‐Jun‐2010 RB McCormack Yes rake 

2986 Eleotridae Gobiomorphus australis striped gudgeon mix x 1 NSW Australia Creek xing Duffy Road (Terrigal Lagoon Catchment) 33.44152 151.42627 23 10‐Jun‐2010 RB McCormack Yes trap 

2987 Poeciliidae Gambusia holbrooki mosquito fish mix x 1 NSW Australia Creek xing Duffy Road (Terrigal Lagoon Catchment) 33.44152 151.42627 23 10‐Jun‐2010 RB McCormack Yes trap

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