REEF FISHES OF NE KANGAROO ISLAND: A NURSERY ROLE FOR EASTERN COVE

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REEF FISHES OF NE KANGAROO ISLAND: A NURSERY ROLE FOR EASTERN COVE?

S.A. Shepherd1, J.L. Baker2, A.R. Brown3 and H.M. Crawford

4,5

1

Email: [email protected] Senior Research Fellow, SARDI Aquatic Sciences PO Box 120 Henley Beach SA 5022.

2 J.L Baker, Marine Ecologist, Somerton Park, SA, 5044. Email: [email protected]; 3

Dept for Environment and Heritage, GPO Box 1047, Adelaide SA 5011

4Visual Artist, [email protected] 5

Marine Life Society of South Australia http://www.mlssa.asn.au

H. Crawford H. Crawford

Supplementary Report for Commonwealth Department of the Environment, Water, Heritage and the Arts

Envirofund Project 63120 October 2009

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REEF FISHES OF NE KANGAROO ISLAND: A NURSERY ROLE FOR EASTERN COVE?

SUMMARY

Reefs in Eastern Cove and American River (called the estuary) and at nearby open coastal sites outside Nepean Bay and Eastern Cove were surveyed in November 2007. In all, 42 fish species were recorded commonly in visual censuses over 7 days, and 7 additional species recorded during accompanying benthic searches of shallow reef habitats. Of the common species, five species showed patterns of abundance related to environmental or other gradients. The abundance of blue groper juveniles peaked ~7 km within the estuary declining toward the entrance and further in, whereas sub-adults declined with distance within the estuary. Sweep and scalyfin declined in abundance with increasing distance within the estuary, whereas weed whitings showed the reverse trend. The abundance of herring cale was correlated with the abundance of its preferred food, the laminarian Ecklonia radiata. Abundances of other species were too low to show significant relationships with particular variables. However, juveniles of several species were abundant within the estuary, emphasizing its role as an important fish nursery.

INTRODUCTION

The reef fish fauna of sheltered embayments and estuaries is not well known in South Australia, mainly because attention has hitherto focused on fish associated with seagrass or sandy, estuarine habitats (Gillanders et al. 2008; Jones et al. 2008). On Kangaroo I. there is only one estuary of note―Nepean Bay, Eastern Cove and American River―and, although the algal and seagrass ecology of American River has long been known (Womersley 1956), the fish fauna is known mainly from (i) a summary of museum collections made since the late 19th

century, including two museum expeditions in 1966 (SA Museum) and 1975 (joint Australian and SA Museums) (Glover, in Tyler et al., 1979, cited by Kinloch, 2005); and (ii) an unpublished report by Duyverman (1976), who used 60 x 2 m set and haul nets with 10 mm mesh to catch fish at 6 sites in American River Inlet and Pelican Lagoon from 25-31 October 1976. In recent years, collection of specific taxa (e.g. gobies) have also been made (M. Hammer, unpubl. data, and in Gillanders et al., 2008).

In this study, the abundance of reef fishes was examined on near-shore rocky reefs in American River and Eastern Cove, and on reefs outside these bays, including Kangaroo Head and Christmas Cove (eastern edge of NE bays region of Kangaroo Island); a site near Point Marsden (western edge of NE bays region of KI) and in Backstairs Passage (Cape Coutts), during accompanying studies investigating uncommon and cryptic species. Earlier reef fish surveys of Kangaroo I. have concentrated on exposed and semi-exposed coasts (e.g. Shepherd et al., 2002, 2004; Edgar et al., 2006), and little attention has previously been given to the reef fish fauna of sheltered waters. The survey presented here was carried out from 10-17 November 2007.

Figure 1: Map of NE Kangaroo Island, with survey sites as listed in Table 1

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METHODS The location of sites surveyed is shown in Figure 1. Surveys used the visual census technique in which divers or snorkellers swim in a given direction, recording the number and size of fishes within a 5 m swathe over a distance of 100 m. The authors are all well experienced in the method, and have been trained in estimating fish sizes correctly. Experience with a 100 m line have shown that this takes ~10 min swimming time at the speed at which we customarily record number and size of fishes, and in this study we used 10 min swims as an estimate of a 100 m transect. Visibility was generally high (6-8 m) during the surveys, except for Cape Coutts where it fell to ~ 4 m. At each site we used a minimum of 4 replicates, and in this report we present data for groups of 4 replicate 100 m swims, with an estimated total coverage of 2000 m2

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Habitat substratum characteristics were noted, major algal canopy species recorded, and an index of exposure estimated subjectively according to the dominant macroalgal canopy species present (see Shepherd & Brook 2007). Also, we estimated rocky bottom relief, according to the average elevation of the reef above the surrounding bottom under the transects. To estimate distance within the estuary from the open coast for sites within Eastern Cove, we drew a straight line geodesic from Point Marsden to Hog Point (near Penneshaw) on a map, and measured the shortest straight line distance from each site to that line. In this report we use the term ‘estuary’ to refer to the whole Nepean Bay/Eastern Cove embayment, because it is a weak reverse estuary with slightly higher salinities in its highest reaches in Pelican Lagoon compared with the waters of Investigator Strait (Womersley 1956).

RESULTS AND DISCUSSION

Habitats The type of rocky bottom substrate and the dominant algal canopy species are given in Table 1. Other details of sites (relief, visibility, exposure index, canopy cover) and numbers and species of fish encountered (numbers 2000 m2

) are given in Appendix 1.

Table 1. Bottom topography and algal dominants at 16 surveyed sites, ordered from west to east.

Site Substratum Algal canopy species 1. Emu Bay eastern caves Schists, high relief reef 1-2

m. Inshore extensive caves Ecklonia, C. moniliformis, C. subfarcinata, Acrocarpia

2. Emu Bay nr White Point 3. Ballast Head Schists inshore, extensive

debris and concrete piles Ecklonia, C. polycystidea

4. Brown Beach Calcrete platform reef, and sandy patches with seagrass

C. subfarcinata, C. polycystidea, Caulocystis, Scaberia, Sargassum cf linearifolium; Caulocystis

5. Baudin Beach S. Low, patchy calcrete reef, with several continuous low ledges through area

Ecklonia, Caulocystis, mixed Sargassum spp. (e.g., S. decipiens, S. paradoxum, S. in linearifolium group), C. polycystidea and C. botryocystis.

6. Baudin Beach W. 7. Baudin Beach N. 8. American Beach West Calcrete boulders and sandy

patches with seagrass C. polycystidea, C. monilifera, Scaberia, Sargassum spp., Gelidium (bleached), corallines. 9. American Beach N.

10. Kangaroo Head W. Schists, high relief reef. Ecklonia, Seirococcus, C. moniliformis, C. monilifera, Sargassum spp. Gelidium 11. Kangaroo Head E.

12. Christmas Cove W Schists, low relief, with boulders

Ecklonia, Seirococcus, C. moniliformis, C. monilifera, Sargassum spp. (wave-degraded), Gelidium. 13. Christmas Cove E.

14. Hog Point, Penneshaw 15. Cape Coutts 1. Schists, high relief reef Ecklonia, Cystophora monilifera, C. moniliformis and

other Cystophora spp., Sargassum spp., Caulerpa, Xiphophora on rock faces

16 Cape Coutts 2.

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Furthest within the estuary, sponge, seagrass and low rubbly habitats are common in the channel leading into Pelican Lagoon (Figure 2A). A feature of this habitat is the strong N-S tidal currents of up to 1.5 m sec-1, sweeping the bottom, and flowing continuously, except during neap tides or at high and low water. In the shallow subtidal at Muston (inner western American River), in patches seaward of the Zostera seagrass fringe, the dominant macroalgae include large clumps of the green alga Caulerpa remotifolia, and the brown algae Caulocystis, and Hormosira banksii (the form labillardieri, with large vesicles), plus various epiphytic red algae, including Spyridia. There are abundant large sponges (individuals 50-60 cm across), and high densities of large Pinna razor fish, scallops, and decorator crabs. Large sponges increase in density towards the centre of the channel. Gobies were the most commonly observed fishes, including one species matching the description of Tamar Goby Afurcagobius tamarensis (which has been recorded in the area e.g. SAMA Ichthyology No. F05069; DEH-SA, 2007 and references therein), and also other sand gobies (Nesogobius, of which 4 species are known from American River – Hoese & Larson 2006; Gillanders et al. 2008). At Muston, gobies were recorded at high densities (~15 m-2

in some areas). Juvenile weed whiting and juvenile moonlighters were also recorded.

Further down the estuary toward the entrance (Site 3 in the west, and Sites 4-9 in the east) depths are shallow, and calcrete low relief platforms are common (see cover picture), with occasional overhanging ledges providing shelter for fish (cover photo, and Figure 2B). Here, algal forests of some canopy species, sometimes 1-1.5 m in height, may form a semi-closed canopy, providing shelter and food for numerous fish species (Figure 2C). In other places, where a thin veneer of sand covers the rocky substratum, species such as Scaberia, are more common, and form a much more open forest (Fig. 2D). Further toward the open coast, as wave action increases, the canopy species such as C. polycystidea etc give way to species better adapted to greater water movement (see Appendix 1), and on the open coast the habitat is dominated by species adapted to moderate to strong water movement (e.g. Cystophora spp, Seirococcus).

Figure 2A: Shallow subtidal at Muston, American River. Photo: J. Baker

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Figure 2B: Juvenile blue groper and silver drummer at American Beach, Eastern Cove. Photo: J. Baker

Figure 2C: Border between seagrass bed and algal-covered shallow subtidal ledge, Baudin Beach, Eastern Cove. Photo: J. Baker.

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Figure 2D: Shallow subtidal sandy and rocky (ledges and rubble) habitat, Brown Beach, Eastern Cove. Photo: H. Crawford.

Fish communities In Appendix 1 fish species are ordered ecologically in terms of the part of the water column which they inhabit. Group 1 are pelagic species found throughout the water column; Group 2 are species associated with sand or seagrass that wander into reef areas; Group 3 are benthic omnivores or carnivores; Group 4 are species which live and move about under the algal canopy or rest in shelter; and Group 5 are cave-dwelling or cryptic species.

Sites varied in terms of exposure to wind waves and swell from extreme shelter in American River to moderate exposure on sites on the north coast of the Island. The most sheltered sites were nurseries for juveniles of several species of fish, e.g. sea sweep, silver drummer, zebra fish, blue-throated wrasse, blue groper, leatherjackets, and moonlighters (6-banded coral fish). Juveniles of not all of these species are obligately associated with sheltered bays, as some of them, e.g. juvenile sweep and blue-throated wrasse, also occur on more exposed coasts, but in locally sheltered habitats. Sheltered bays are well known as nurseries for other species associated with sandy bottom e.g. King George whiting, but these were seldom seen in our censuses, which focused on reefs. A cleaning station was observed under a shallow ledge at Baudin Beach, where a moonlighter was cleaning magpie perch, blue-throated wrasse and other reef species in the vicinity.

Factors affecting the distribution and abundance of fish are numerous, and include: bottom relief, exposure to swell or waves, algal composition and canopy cover, and preferred food and its availability. These factors together determine the habitats in which fish are found. As an example of one important factor, we show the relation between rocky bottom relief and abundance of site-attached reef species (Groups 3-5) within the estuary and on the open coast (Figure 3). For this comparison we omitted two schooling species, zebra fish and hula fish, which vary greatly in abundance due to chance encounter of large schools with the diver. It is evident that the abundance of site-attached species increases markedly with bottom relief for sites on the outer coast, although the data are noisy, but that the pattern is different within the estuary. Here, even though bottom relief is generally very low, abundances are often much higher for a bottom given relief than predicted outside the estuary. A factor contributing to the higher levels of abundance within the estuary may be its role as a nursery for juveniles of e.g. six-banded coral fish, silver drummer, zebra fish, blue-throated wrasse, as well as other species considered below. Of these species, young zebra fish were especially common, and aggregated in groups around low ledges in the shallow subtidal (to ~2 m depth).

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y = -19.19x2 + 101.6xR² = 0.266

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Rocky Bottom relief (m)

Reef-attached fish species

Outer coast

Estuary

The Ballast Head site (3) was of particular interest, because fish abundances there were higher than elsewhere in the estuary, due not only to the large numbers of hula fish and juvenile zebra fish, but also to other species. Examination of Figs 4-6 show that the Ballast head datum (at 10 km within the estuary) was substantially higher than adjacent points. These high abundances are likely due to the moderate tidal currents, the moderate to high bottom relief, and the extensive crevice habitat, resulting from the mass of debris left after demolition of the Ballast Head loading wharf.

In this report we also detail habitat relationships for five species, which were apparent from the data. Such relationships could only be examined for common species on specific, measured gradients, given the small number of surveyed sites. We present lines of best fit for these species, although the trends suggested may not always be statistically significant.

Figure 3. Plot of change in abundance of reef-attached species (Groups 3-5) with rocky bottom relief at sites outside American River/Eastern Cove (solid diamonds), compared with sites within the estuary (hollow squares). Curve of best fit is shown for Outer Coast data.

Blue groper Abundances of juveniles (< 20 cm) of this species peaked at 7-9 km within the estuary, declining further within, and toward the entrance. In contrast, sub-adults (20-60 cm) showed the opposite trend, being absent furthest within the estuary, but increasing in abundance toward the open coast (Figure 4). Adults (> 60 cm) were only seen on the open coast adjacent to deep water at Sites 15, 16 (Cape Coutts).

The blue groper is a bottom feeder, and earlier studies (Shepherd 2006; Shepherd & Brook 2007) have shown that juveniles (< 20 cm i.e. < 1 year-old) are restricted to sheltered waters, such as back-reef locations and lagoons sheltered from strong wave action. Their abundance data in these surveys have especial interest, because they show that very large estuaries, extending over >300 km2

, like Nepean Bay/Eastern Cove have an important nursery role, commensurate with their size, for this species. The increase in abundance of sub-adults toward the outer parts of the estuary suggests that with growth in size individuals migrate toward the open coast. This hypothesized movement is consistent with the food requirements of the groper, which switch with increasing size to larger prey (using ram-and-bite technique) or to epifauna in algal mats (using bite-suction technique), available on more open exposed reefs with high algal cover (see Shepherd 2006).

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Blue groper

y = -0.62x + 7.14R2 = 0.1802

y = -0.019x3 + 0.19x2 + 0.23x + 0.10R2 = 0.4522

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Sea sweep

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Figure 4. Change in abundance of juvenile < 20 cm)(▲) and sub-adult (20-60 cm) (■) blue groper with increasing distance within Eastern Cove/American River estuary. Curves of best fit are shown. Each point is a datum from one 2000 m2

survey.

Sweep and scalyfin Sea sweep and scalyfin were most abundant outside the estuary, and both species declined in density with distance within (Figures 5 & 6). This distribution pattern can also be explained in terms of food availability and shelter. Sweep are mainly planktivores, but are also known to feed on benthic red algae, and we hypothesize that their food supplies are more abundant where currents are stronger and reefs are of moderate to high relief (Shepherd & Baker 2008). As juvenile (< 10 cm) sweep followed the same distribution pattern as adults, we present density data for all sizes combined.

Figure 5. Change in abundance of sea sweep with distance within Eastern Cove/American River estuary, with curve of best fit.

Scalyfin is a territorial species, which browses mainly on red algae in moderately exposed reef habitats with reef of moderate to high relief (Shepherd et al. 2008; unpublished data)—habitats rare within the estuary but common outside. Scalyfin also establish their territory around a shelter hole, also more commonly found on reef of moderate to high relief.

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Scalyfin

y = 0.0403x2 - 0.6246x + 2.9779R2 = 0.1762

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Sharp-nosed and long-rayed weed whitings

y = -0.5184x2 + 7.0739x - 3.6018R2 = 0.5047

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Figure 6. Change in abundance of scalyfin with distance within Eastern Cove/American River estuary, with curve of best fit.

Sharp-nosed weed whiting (Siphonognathus caninus) and long-rayed weed whiting (S. radiatus) These two species are not easily distinguished in the field. The majority seen by us were the former species (maximum size ~14 cm), but the largest ones seen (~25 cm) were likely the latter species. So, for the purposes of this graph they are combined. Abundances of the two species, particularly juveniles, were highest well within the estuary and declined toward open water (Figure 7). Hence, the data suggest that both species may be obligately associated with seagrass near reef edges and/or calm-water habitats. Of more than 175 shallow reef sites so far surveyed along the SA coast from 2002-2007, the abundance of S. caninus was highest at the inner eastern reefs of Eastern Cove (unpublished data).

Figure 7. Change in abundance of sharp-nosed weed whiting and long-rayed weed whiting with distance within Eastern Cove/American River estuary, with curve of best fit.

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Herring cale

y = 0.1541xR2 = 0.4377

02468

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Herring cale This species was mainly recorded on reefs where the laminarian Ecklonia radiata, its main diet, was found. Ecklonia cover was highest on the open coast, but at times patches were seen on elevated reef well within the estuary, as at Site 3 (Ballast Head). A plot of this species’ abundance versus Ecklonia cover recorded on the transects shows a significant linear relation with Ecklonia % cover (Fig. 8), a result similar to that recorded by Shepherd & Brook (2003) at Nuyts Archipelago.

Figure 8. Change in abundance of herring cale with Ecklonia cover within and at entrances to Eastern Cove/American River estuaries.

Other species In addition to the species listed in Appendix 1, we recorded other species not on transects during the study at Eastern Cove and American River. We also dived American River in December 2008, and recorded several most species not seen on the previous dive in 2007. These, together with those recorded by Duyverman (1976), are listed in Appendix 2. The data of Duyverman (1976), although not strictly comparable with our data, due to different collecting methods, nevertheless have interest. He recorded spiny-tailed leatherjacket, queen snapper (i.e. southern blue morwong) and gummy shark as common to very common, whereas they were not recorded by us at all in 2007, although both surveys were done at about the same time of year. It is likely that the gummy shark has substantially declined in numbers since the 1976 survey (see chapter on Triakidae, in Baker 2009), and this situation may also apply to queen snapper, which is fished extensively in more open waters off Fleurieu Peninsula (see Appendix 3, Shepherd & Baker 2008; and chapter on Cheilodactylidae, in Baker 2009). Queen snapper were recorded at several sites during similar fish surveys along the northern coast of Kangaroo I. in 2002 (Shepherd & Baker 2008), and at Snug Cove and Pt Marsden during our north coast survey in 2008.

ACKNOWLEDGMENTS

The authors thank the Department for Environment and Heritage in South Australia for a Wildlife Conservation Fund grant that enabled this survey to be undertaken, in conjunction with a study on distribution of uncommon and cryptic fishes along the central SA coast. We also thank Chris Hall (MLSSA), Danny Brock and Martine Kinloch (Coast and Marine program of KI NRM Board), Tony Geyer (KI resident and dive boat driver extraordinaire), and Kevin Smith, for helpful field support, equipment, and good company. Thanks also to John Lavers and family for diving equipment and advice.

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REFERENCES Baker, J.L. (2008) Marine Species of Conservation Concern in South Australia: Technical Report – Bony and

Cartilaginous Fish. Prepared for the South Australian Working Group for Marine Species of Conservation Concern. (J. Baker, consultant; S.A. Department for Environment and Heritage; Marine and Coastal Community Network; Reef Watch, Conservation Council of South Australia; and Threatened Species Network).

DEH-SA (2007) Kangaroo Island Natural Resources Management Region: Estuaries Information Package. (Department for Environment and Heritage, South Australia).

Duyverman, H. (1976) Data: American Inlet Aquatic Reserve. Report to Dept Fisheries 27 pp. (Dept Fisheries, Adelaide).

Edgar, G.J., Barrett, N.S., Brook, J.B., McDonald, B. and Bloomfield., A. (2006) Ecosystem monitoring inside and outside Sanctuary Zones within the Encounter Marine Park - 2005 baseline surveys. TAFI Internal Report. Tasmanian Aquaculture and Fisheries Institute.

Gillanders, B. M., Elsdon, T.S. & Hammer, M. (2008) Estuaries of Gulf St Vincent, Investigator Strait and Backstairs Passage. In ‘Natural History of Gulf St Vincent’ (Eds S.A. Shepherd, S. Bryars, I. Kirkegaard & P. Harbison) pp 181-200. (Royal Society of SA, Adelaide).

Hoese, D.F. & Larson, H.K. (2006) Description of two new species of Nesogobius (Pisces: Gobioidei: Gobiidae) from southern Australia. Memoirs of Museum Victoria 63(1), 7–13.

Jones, K. Connolly, R.M. & Bloomfield, A.L. (2008) Ecology of fish in seagrass. In ‘ Natural History of Gulf St Vincent’ (Eds S.A. Shepherd, S. Bryars, I. Kirkegaard & P. Harbison) pp 166-180 (Royal Society of SA, Adelaide).

Kinloch, M. (2005) Review of Kangaroo Island Marine, Coastal and Estuarine Biodiversity Monitoring and Research Programs. Kangaroo Island Natural Resources Board, Kingscote, Kangaroo Island.

Rowntree, J, (2004) Patterns of Species Richness and Abundance of Fish in South Australian Estuaries, School of Earth and Environmental Sciences, University of Adelaide, Adelaide, South Australia.

Shepherd, S.A. (2006) Ontogenetic changes in diet, feeding behaviour and activity of the western blue groper, Achoerodus gouldii. In ‘The Marine Fauna and Flora of Esperance, Western Australia Volume 2 (Proceedings of the 12th

Shepherd, S.A. & Baker, J.L. (2008) Reef fishes of lower Gulf St Vincent. In ‘Natural History of Gulf St Vincent’ (Eds S.A. Shepherd, S. Bryars, I. Kirkegaard & P. Harbison) pp 301-320. (Royal Society of SA, Adelaide).

International Marine Biology Workshop) (F.E. Wells, D.I. Walker and G.A. Kendrick Eds) pp. 477-494 (Western Australian Museum, Perth).

Shepherd, S.A. & Brook, J.B. (2003) Encounter 2002 expedition to the Isles of St Francis, South Australia: reef fishes. Trans R. Soc. S. Aust.127, 269-279.

Shepherd, S.A. & Brook, J.B. (2005) Foraging ecology of the western blue groper, Achoerodus gouldii, at the Althorpe Islands, South Australia. Trans R. Soc. S. Aust.129, 202-208.

Shepherd, S.A. & Brook, J.B (2007) Distribution and ontogenetic shifts in habitat and abundance of the temperate western blue groper, Achoerodus gouldii. Journal of Fish Biology 71, 1–22.

Shepherd, S., Brook, J. and Brown, A. (2002) A preliminary survey of the Western Blue Groper on Kangaroo Island. Reef Watch report. Conservation Council of South Australia, Adelaide. 10p.

Shepherd, S.A., Clark, M. & Ferguson, G. (2008) Habitat-dependent foraging behaviour and diet of the scalyfin, Parma victoriae, in South Australia. Trans R. Soc. S. Aust.(ms submitted)

Shepherd, S., Kinloch, M. A and Bartram, H. (2004) A pilot study of inshore reef fish assemblages on Kangaroo Island. Kangaroo Island Natural Resources Board, Kingscote. 7p.

Tyler, M. J., Twidale, C. R. and Ling, J. K. (Eds) (1979) Natural History of Kangaroo Island (1st edn). Royal Society of South Australia, Adelaide. 184p.

Womersley, H.B.S. (1956) The marine algae of Kangaroo Island. IV. The algal ecology of American River Inlet. Aust. J. Mar. Freshw. Res. 7, 64-87.

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Appendix 1. Sites surveyed (each 2000 m2

) and numbers and species of fish recorded, with data on relief, visibility, exposure, and distance of site from outer coast (see text). EB=Emu Bay; BH=Ballast Head; BrB=Brown Beach; BaB=Baudin Beach; AB=American Beach; KH=Kangaroo Head; XC=Christmas Cove; HP=Hog Point, Penneshaw; CC=Cape Coutts.

Sites EB EB BH BrB BaB BaB BaB AB AB KH KH XC XC HPt CC CC E Pt S W N 1 2 E W W E 1 2 Site Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Replicates x 100 m 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 Depth 3 3 3.5 2 2.5 4 3 3 4 3.5 3 3.5 3 5 6 4 Rocky bottom relief (m) 1.5 1.5 1.5 0.1 0.2 0.3 0.4 0.3 0.2 2.75 2.5 0.4 2 0.9 2.5 2 Visibility (m) 8 8 8 8 8 8 8 8 8 8 8 6 6 5 4 4 Exposure index (0-4) 2 2 1 0 0 0 0 0 0 1 1 2 2 2 2 2 % algal canopy cover 90 80 60 25 70 80 75 20 20 50 50 60 60 90 80 80 Distance from outer coast 0 0 10 11 9 9 8 7 7 3 3 1 1 0.5 0

0 Fishes Density/2000m2 Group 1 Arripis truttaceus WA salmon 100

Dinolestes lewini Long-finned pike 1

Scorpis aequipinnis sea sweep 78 60 27 1 6 1 11 4 4 41 31 38 7 13 52

20 Enoplosus armatus old wife 8 4 17 15

Arripis georgianus tommy ruff 40

Group 2 Trigonorrhina fasciata fiddler ray 1

Platycephalus bassensis sand flathead 1

Sillaginodes punctata King George whiting 1 2 1

Siphonognathus caninus sharp-nosed weed-whiting 11 28 22 7 39 33 1

Upeneichthys vlamingii red mullet 2 2 1 1 1

Group 3 Achoerodus gouldii western blue groper 5 7 1 2 5 1 9 5 19 6 18 10 11 14

4 Dactylophora nigricans dusky morwong 3 2 1 2 1 4 1 2 1

Kyphosus sydneyanus silver drummer 16 22 60 1 10 23 34 27 17 1 20 12

14 Pentaceropsis recurvi-rostris l-snouted boarfish 2

Cheilodactylus nigripes magpie perch 14 4 7 1 3 7 4 1 8 6 2 2 8 6

1 Girella zebra zebra fish 30 52 232 5 5 45 46 107 40 1 89 7 3 5 3 Notolabrus tetricus blue-throated wrasse 103 47 39 21 9 95 25 45 49 110 70 48 66 64 30

48 Notolabrus parilus brown-spotted wrasse 1

Dotalabrus aurantiacus Castelnau’s wrasse 2 1 2 1

1 Austrolabrus maculatus black-spotted wrasse 3 2

Ophthalmolepis lineolatus maori wrasse

2

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Sites EB EB BH BrB BaB BaB BaB AB AB KH KH XC XC HPt CC CC E Pt S W N 1 2 E W W E 1 2 Meuschenia flavolineata y-stripe leatherjacket 16 2

1 Meuschenia freycineti 6-spined leatherjacket 1

Meuschenia hippocrepis horseshoe leatherjacket 9 10 7 1 2 1 1

Eubalichthys gunnii Gunn's leatherjacket 1 2

Chelmonops curiosus western talma 2 2 1 4

Group 4 Othos dentex harlequin fish 1

Aplodactylus arctidens southern sea carp 1 1 1 1 2

2 Odax acroptilus rainbow cale 1

Odax cyanomelas herring cale 14 3 4 6 4 3 1 10

Pictilabrus laticlavius senator wrasse 7 3 3 2 4 2 3 2 3 7 2 3

Siphonognathus beddomei pencil weed whiting

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Parma victoriae Victorian Scaly fin 9 3 3 1 2 4 1 4

Tilodon sexfasciatus 6-banded coral fish 3 2 15 2 11 19 7 4 2 2 4 1

Aracana ornata ornate cowfish 1

Bovichtus angustifrons dragonet 1 1

Lepidoblennius marmoratus western jumping blenny

2 1

Group 5 Pempheris multiradiata common bullseye 24 3

Parapriacanthus elongatus slender bullseye

3

Trachinops noarlungae yellow-headed hulafish 445 20 85 375

Norfolkia clarkei common three-fin 1 1

Number of species 17 13 25 11 19 18 12 12 11 11 12 8 12 10 13 9 Number of individuals 347 210 877 48 114 332 522 247 166 210 218 122 103 139 240 94

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Appendix 2. Other fish species recorded in American River and Eastern Cove by one or more of our team during dives in 2007 and 2008. * indicates those also recorded by Duyverman (1976). Frequency of encounter in the estuary according to Duyverman, indicated as follows: vc = very common; c = common; occ = occasional. ES = recorded during our Envirofund-supported surveys but not previously by Duyverman. NB This list contains only the species observed by Duyverman, and by our team members during the 2007 and 2008 surveys. It is not a complete fish species list for American River. For example, a number of other goby species have been recorded from the river, including Nesogobius maccullochi, N. greeni and N. pulchellus (Hammer, in Gillanders et al., 2008). It is also noted that Duyverman (1976) recorded a hardyhead as very common, but its identity is uncertain.

Acanthaluteres brownii spinytail leatherjacket vc* Afurcagobius tamarensis Tamar goby (ES - unverified) Alabes dorsalis common shore-eel c* Arenigobius bifrenatus bridled goby vc* Aspasmogaster tasmaniensis Tasmanian clingfish c* Aulopus purpurissatus sergeant baker occ* Callogobius mucosus sculptured goby vc* Cristiceps australis southern crested weedfish vc* Engraulis australis anchovy (ES) Eubalichthys mosaicus mosaic leatherjacket occ.* Favonigobius lateralis southern longfin goby Girella tricuspidata luderick (ES) Gymnapistes marmoratus cobbler or soldierfish occ* Haletta semifasciata blue rock or weedy whiting vc* Helcogramma decurrens black-throated threefin occ* Mustelus antarcticus gummy shark vc* Nemadactylus valenciennesi queen snapper c* Nesogobius sp. 5 sicklefin Sandgoby (ES) Nesogobius spp. (2 others in addition to sp. 5, not identified)

Parablennius tasmanianus Tasmanian blenny vc* Pelates octolineatus striped trumpeter or perch c* Rhomboselea tapirina greenback flounder occ* Sphyraena novaehollandiae snook /short-finned pike occ* Stigmatopora argus spotted pipefish (ES) Stigmatopora narinosa southern gulfs pipefish (ES) Tasmanogobius gloveri Glover’s Tasman Goby (ES) Trygonoptera mucosa western shovelnose stingaree (ES) Trinorfolkia cristata crested threefin (ES) Vincentia (reported as badia) (scarlet) cardinalfish c*