Fish

There is professional fishing in Princess Royal Harbour, Oyster Harbour and King George Sound. The main fish caught are pilchards, which are netted in King George Sound and Princess Royal Harbour. Pilchards are processed for pet food and angling bait in Albany. Other important commercial fish species include cobbler, leatherjacket, Australian herring and Australian salmon. There is an oyster farm in Oyster Harbour.

Fisheries Western Australia annually reports on commercial fisheries of the south coast. A combined report is given for the fishery of Princess Royal Harbour and King George Sound. Unlike other estuaries which are permanently open to the sea along the South Coast, this fishery has a lot of different fish species that it catches. The main fish caught ('main' here means the annual catch exceeds 10 t) are pilchard, Australian herring and leatherjacket. These different sorts of fish are caught mainly because Princess Royal Harbour and King George Sound get very little fresh water, and so salinity is usually relatively stable. The water in the harbour is more like a coastal bay than a changing estuary. So a lot of different ocean fish come into the harbour and sound.

Mercury contamination of the sediments within Princess Royal caused the closure of the western end of the harbour, from 1984 to 1992, to the capture of all fish and shellfish. During this time the fish catch for the harbour and sound (comprising 25 species excluding pilchards) declined marginally to a constant level and then, once reopened to fishing in 1992, increased to 111 t. The key species caught included Australian herring (24.9 t), leatherjacket (22.2 t), cobbler (17.7 t), yellowtail scad (5.2 t), flathead (4.3 t), King George whiting (3.2 t) and garfish (2.9 t).

Fishing is also an important leisure activity for the people of Albany. A lot of people fish from the town jetty and other places around the harbours.

Fishery management in the harbours is the responsibility of Fisheries Western Australia. The agency has a regional office based in Albany and gives specialist advice on the fishery to management bodies such as the Albany Waterways Management Authority (AWMA). AWMA in turn gives advice to Fisheries Western Australia on the impact commercial fishing may have on the environment of the waterways. Particularly important to AWMA is what effect commercial fishing, especially aquaculture, has on the seagrasses in Princess Royal and Oyster harbours. If commercial fishing is going to continue in these harbours, the water quality must be good. There must be places for the fish to feed and breed. Seagrasses are essential for all of these things. If the seagrasses decrease or die, then commercial fishing will probably end as well.

Invertebrates

No systematic invertebrate surveys of Princess Royal and Oyster harbours or the King and Kalgan rivers have been done. However, some samples have been taken.

There are about 133 species of mollusc found in Oyster Harbour (of which about 55 have been found alive). Most of these species are regarded as marine species (species which only enter estuaries for short periods of time or at irregular intervals) or `marine affinity' species (species which mainly live in the sea but are found frequently in estuaries).

Other marine animals found in the harbour include starfish and the sea urchin Temnopleurus michaelsenii. One hundred and thirty-four species of Foraminifera have also been found, though only a dozen were common to the harbour. One, Elphidium sp., was very common throughout the harbour.

Several marine affinity species live on the shell beds in the lower King River, but not further upstream. In the Kalgan River the snail Bembicium, barnacles (Balanus) and tube worms (Ficopomatus) are abundant on rocks and logs downstream of the rock bar and there are mud oysters (Ostrea angasi) in the lower reaches. The estuarine mussel Xenstrobus securis is common in both rivers. Elphidium sp. is the dominant species of Foraminifera, with only two other species found in the Kalgan River and six in the lower reaches of the King River.

The invertebrates listed above are also found in Oyster Harbour.

Aquatic vegetation in the Albany harbours

Fringing and saltmarsh vegetation around the waterways

Fringing vegetation is important in the Albany waterways ecosystems. Saltmarshes on the edges of the harbours are usually flooded by the tides. During the summer months, when the tides are lower, the already salty sea water remaining in the marsh can become extremely salty because of evaporation. Plants in these areas, such as samphires, are mostly salt-tolerant. Areas of the marsh which are less saline support rushes.

Saltmarshes are an extremely productive part of the estuarine ecosystem. They are a major source of detritus which provides food for other organisms in the ecosystem.

There are three main saltmarshes around Oyster Harbour.

1. An extensive marsh on the south-western shore where Yakamia Creek and the Lake Seppings creek enter the harbour. This marsh is dominated by astartea (Astartea fascicularis), wattle (Acacia myrtifolia) and greenbush (Oxylobium lanceolatum). The outer fringe of the marsh is dominated by shore rush (Juncus kraussii), backed by saltwater paperbark (Melaleuca cuticularis) trees and twig rush (Baumea juncea).

2. Tidal mudflats and shallows upstream and downstream of the Lower King Bridge. Plants found in this area include samphire (Sarcocornia quinqueflora) and seablite (Suaeda australis). Halosarcia halocnemoides and Halosarcia lepidosperma are found in the drier parts, while shore rush and saltwater paperbarks are found on rising ground along the shore.

3. The south-eastern shore features a narrow samphire fringe with Suaeda australis and Halosarcia spp., with patches of shore rush and saltwater paperbark marsh inland.

In Princess Royal Harbour saltmarshes are found along the south-eastern shore of Shoal Bay and as far west as Limekilns Point; in patches between Limekilns Point and Pagoda Point; between Stuarts Head at Little Grove and the western shore of the harbour; immediately west of the Wool Stores on the north-western corner of the harbour and in patches to the eastern side of the Town Jetty. These saltmarshes are made up of mixed and isolated open herb and sedge communities with plants such as trailing joint weed (Hemichroa pentandra), saltwater couch (Sarconia quinqueflora), creeping brookweed (Samulus repens), silky wilsonia (Wilsonia humilis), streaked yellow grass (Triglochin stiata) and shore rush.

Both harbours have areas where there is substantial freshwater seepage. In these areas freshwater vegetation is able to survive well into the tidal zone. These plants are twig rush, growing on the landward side of shore rush areas, and coastal saw sedge (Gahnia trifida). Other species found with these communities are coast sword sedge (Lepidosperma gladiatum); Acacia littorea, Leucopogon obovatus and coast daisy bush (Olearia axillaris); knotted club rush (Isolepis nodosa) and native tufted grass (Poa porphyroclados).

Patches of saltwater paperbark forest are found on the shore where there isn't much fresh groundwater seepage. The understorey is sedges and salt-tolerant rushes also found elsewhere in the harbours.

Inland from Princess Royal harbour, communities of Warren River cedar (Agonis juniperina) and Western Australian peppermint (Agonis flexuosa) form low and stunted woodlands. Other species found in these communities are Acacia littorea, scrub sheoak (Allocasuarina humilis), sea berry saltbush (Rhagodia baccata) and the herb, angled lobelia (Lobelia alata).

Western Australian peppermint and swamp banksia (Banksia littoralis) are found with paperbarks (Melaleuca incana) and saltwater paperbark in swampy sand and peat areas. Sedges and rushes are also common, along with small- to medium-sized shrubs such as the Australian blue bell (Sollya heterophylla), rose banjine (Pimelia rosea), coast beard heath (Leucopogon parviflorus), greenbush, basket bush (Spyridium globulosum), and variable leafed hakea (Hakea varia).

Western Australian peppermint and an understorey of sedges and rushes dominate moist sandy rises.

Beach and sandy rise vegetation

Sand and shell grit rises and sand dunes are often found next to beaches, saltmarshes and other areas of waterway fringing vegetation. These sandy areas support communities of shrubs and sedges.

In Princess Royal Harbour this vegetation can be divided into three groups:

1. Open shrubland. This consists of the grey-white cushion bush (Calocephalus Browni), Pimelia imbricata, trailing joint weed and the introduced plant false caper (Euphorbia terracina).

2. Sedgeland. This consists of dense and open patches of sedges and other plants. Common species are knotted club rush, coast sword sedge, false caper and seablite. Other less common species are sea celery (Apium prostratum), shore rush, creeping brookweed and saltwater couch.

3. Sedgeland which colonises dead seagrass and algae washed onto the shore. These sedgeland communities are found along the western shore of Vancouver Peninsula growing on deposits up to a metre deep. These communities consist of Atriplex hypoleuca, sea rocket (Cakali maritima), seablite and pigface (Carpobrutus virescens).

Inland forest vegetation

Behind the saltmarshes grow salt-tolerant saltwater paperbarks and scrub sheoaks. Further inland, in low-lying areas, beyond the influence of salt water, are freshwater paperbarks and flooded gums. Higher ground supports myrtle and tea tree scrub, along with wattle and shrubs like hakea, Jacksonia and Hibbertia. Open forests of marri and banksia with tuart on the higher ground are found further inland again.

Riverine fringing and forest vegetation

In the estuarine reaches of the Kalgan and King rivers the saltwater paperbark is the dominant tree. It usually grows among dense stands of shore rush and coastal saw sedge. In the upper freshwater reaches of the rivers above the rock bars, saltwater plant species are replaced by a fringing forest of marri (Eucalyptus calophylla), Western Australian peppermint and swamp paperbark (Melaleuca rhaphiophylla); a variety of freshwater sedges, including sword sedge (Lepidosperma effusum) and twig rush, and the tall shrub astartea. The thin soils which cover granite outcrops along the river banks support areas of jarrah (Eucalyptus marginata) and one-sided bottlebrush (Calothanus quadrifidus).

Other trees and tall shrubs found further inland, along the freshwater parts of the rivers include flooded gum (Eucalyptus rudis), swamp yate (Eucalyptus occidentalis), river banksia (Banksia seminuda), greenbush, trimalium (Trimalium floribundum) and hakea (Hakea oleifolia). Other plants include sword sedge and the weeds bracken fern (Pteriium esculentum) and sweet vernal grass (Anthoxanthum odoratum). Flooded gums and swamp paperbark dominate in swampy areas and along the banks of the rivers.

Marri and jarrah forest is found along the river banks with river banksias, hakea, astartea, lemon-scented darwinia (Darwinia citriodora), harsh hakea (Hakea postrata) and bracken fern. Ground plants, most of which are introduced weeds, include hispid stinkweed (Opercularie hispidula), loxocarya (Loxocarya flexuosa), purple tassles (Sowerbaea laxiflora), bridal creeper (Myrsiphyllum asparagoides), great brome (Bromus diandrus), yorkshire fog grass (Holcus lanatus), sweet vernal grass, quaking grass (Briza maxima and minor), and annual veldt grass (Ehrharta longiflora).

North of the Porongurup Range the Kalgan River is fringed by marri, flooded gum, swamp paperbark and swamp yate. Smaller shrubs include Melaleuca vinminea, thryptomena (Thryptomene saxicola), dodonaea (Dodonaea ceratocarpa) and lemon-scented darwinia. Along the river banks are trees also found along the floodway, the limestone marlock (Eucalyptus decipiens) and the one-sided bottlebrush.

In the upper reaches of the Kalgan the water becomes increasingly saline and estuarine species such as samphires and shore rushes, typical of Oyster Harbour, dominate the floodway of the river along with a variety of Melaleuca species (Melaleuca thymoides and Melaleuca viminea). Wandoo (Eucalyptus wandoo) and swamp yate dominate the upper river embankments.

In freshwater areas of the rivers, where fences haven't been built or maintained, livestock have grazed and trampled the native fringing vegetation. Summer fires have destroyed any surviving plants. This has encouraged the growth of introduced, shallow-rooted plants. The loss of deep-rooted native vegetation has led to the erosion and subsidence of the river banks. In the upper region of the Kalgan River, increased salinisation has also killed native fringing forests over large sections. In some cases, salt-tolerant tree species, such as the saltwater paperbark M. cuticularis, have replaced less salt-tolerant species.