sharp point (torndirrup national park) goode beach ... · a small, shallow, rocky-floored embayment...

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40 3.3 ALBANY Sharp Point (Torndirrup National Park) Goode Beach (Vancouver Peninsular near Mistaken Island) Little Beach (Two People’s Bay National Park) Regional setting of the Albany transects Albany experiences a sub-humid Mediterranean climate with warm dry summers and cool wet winters. Mean annual rainfall is 933 mm (Australian Bureau of Meteorology, 2005). It is part of the Esperance Plains BioRegion ( IBRA, 2000). The region is part of the Albany-Fraser Geological Province with Proterozoic-age gneiss and granite forming the bedrock and commonly outcropping along the coast as hills, headlands and islands (Muhling & Brakel, 1985). This rock is largely overlaid inland by Tertiary-age Plantagenet Group sediments (formed during marine transgressions) and near the coast by fluvial or aeolian Quaternary deposits. The latter deposits include estuarine and lagoonal clay, silt and sand, Pleistocene-age limestone and abundant white quartz sand as either mobile or vegetation-fixed dunes. Landforms and sediments of the Albany transects Albany is set in a coastal landscape of great variety and scenic beauty with several magnificent national parks adjacent to the coast. However it was difficult to find representative locations close to the town where the shore could be safely accessed in order to survey vegetation close to sea level. The Sharp Point transect was established in the Torndirrup National Park, south of the Albany suburb of Little Grove. Here tall gneiss cliffs capped with limestone face Torbay on the high energy Southern Ocean. Transect sites comparable to that established by Sauer in 1965 at the Blowholes nearby (where vegetation was sampled down to the splash zone) were avoided for safety reasons. The start of the SWALE 2 transect was at a relatively safe place on the edge of the high plateau adjacent to the Sharp Point lookout. The cliff face below this transect was not surveyed and as such is not shown strictly to scale on the transect diagram (Fig 26). The Sharp Point transect continued inland across the limestone capped plateau, over the low crest of a perched dune and down to a broad valley beyond. Another transect (Mistaken Island- Goode Beach) was established across the Vancouver Peninsular from Goode Beach (on Frenchman’s Bay in King George Sound) and west towards Princess Royal Harbour. The Vancouver Peninsular is a tombolo that formed between gneissic islands in the north and the spine of the

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Page 1: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea

40

3.3 ALBANY Sharp Point (Torndirrup National Park)

Goode Beach (Vancouver Peninsular near Mistaken Island)

Little Beach (Two People’s Bay National Park) Regional setting of the Albany transects Albany experiences a sub-humid Mediterranean climate with warm dry summers and cool wet winters.

Mean annual rainfall is 933 mm (Australian Bureau of Meteorology, 2005). It is part of the Esperance

Plains BioRegion ( IBRA, 2000). The region is part of the Albany-Fraser Geological Province with

Proterozoic-age gneiss and granite forming the bedrock and commonly outcropping along the coast as

hills, headlands and islands (Muhling & Brakel, 1985). This rock is largely overlaid inland by Tertiary-age

Plantagenet Group sediments (formed during marine transgressions) and near the coast by fluvial or

aeolian Quaternary deposits. The latter deposits include estuarine and lagoonal clay, silt and sand,

Pleistocene-age limestone and abundant white quartz sand as either mobile or vegetation-fixed dunes.

Landforms and sediments of the Albany transects Albany is set in a coastal landscape of great variety and scenic beauty with several magnificent national

parks adjacent to the coast. However it was difficult to find representative locations close to the town

where the shore could be safely accessed in order to survey vegetation close to sea level. The Sharp Point

transect was established in the Torndirrup National Park, south of the Albany suburb of Little Grove. Here

tall gneiss cliffs capped with limestone face Torbay on the high energy Southern Ocean. Transect sites

comparable to that established by Sauer in 1965 at the Blowholes nearby (where vegetation was sampled

down to the splash zone) were avoided for safety reasons. The start of the SWALE 2 transect was at a

relatively safe place on the edge of the high plateau adjacent to the Sharp Point lookout. The cliff face

below this transect was not surveyed and as such is not shown strictly to scale on the transect diagram (Fig

26). The Sharp Point transect continued inland across the limestone capped plateau, over the low crest of a

perched dune and down to a broad valley beyond.

Another transect (Mistaken Island- Goode Beach) was established across the Vancouver Peninsular from

Goode Beach (on Frenchman’s Bay in King George Sound) and west towards Princess Royal Harbour. The

Vancouver Peninsular is a tombolo that formed between gneissic islands in the north and the spine of the

Page 2: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea

41Torndirrup Peninsular to the south. It is composed of Quaternary sand dunes overlying muddy estuarine

deposits with sand overlying the gneiss of the former islands in some places. Except for a narrow channel

that provides access for shipping to Princess Royal Harbour in the north, a series of tombolos bar the

harbour from King George Sound. The Goode Beach transect encompassed a foredune (that fronted the

relatively sheltered oceanic environment of King George Sound) and extended west over a rocky outcrop

to a perched sand dune overlying the gneissic bedrock.

The third Albany transect was established about 30km east of the town at Little Beach. This is a rocky

shore site with an unusual sheltered embayment in the south of Two Peoples’ Bay. Little Beach is located

on the western flank of the large granitic headland of Mt Gardner. The terrain landward of Little Beach is a

series of deep quartz sand dunes overlying granitic bedrock at depth.

The beach of the transect is the seaward tip of a narrow band of sand extending from the perched dunes of

the hinterland and terminating at the sea between two granitic outcrops. The sandy beach is situated above

a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just

above mean sea level. Landward from the beach is a seasonally-waterlogged, gently-sloping wetland

(paluslope) extending about 3.5 m above sealevel, encompassing the supratidal zone and the adjacent

lower slope of a quartz dune. (The latter dune rises to a crest 15m in height about 85m inland). The lower

section of the vegetation of this slope (adjacent to the beach) is subject to intermittent storm surges that

bring water of marine salinity and debris into the terrestrial vegetation. Concurrently however there is a

significant seepage of freshwater throughout the year downslope from the landward dune aquifer and most

of this is absorbed by the peat and vegetation of the paluslope.

The most common surface material found in the Albany transects was white, pure quartz sand. At the

foredune on Goode Beach, this sand had a small fraction of black mineral sand grains (of the same fine

size as the dominant pale quartz grains).

Page 3: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea

42Table 9: Albany transect surface sediments

Soil sample site : Transect and landform

Dominant vegetation Sediment description

Sharp Point plateau at start of transect

Low species- rich heath inc. Melaleuca pentagona Templetonia retusa, Pultenaea quaerita, Gahnia sp. Headland & Desmocladus austrinus

Fine-to-medium, cream to light grey carbonate and quartz sand

Sharp Point very low perched dunes over limestone

Closed scrub of Agonis flexuosa with Scaevola nitida, Spyridium globulosum Lepidosperma gladiatum and Acacia littorea

Fine-to-medium, white quartz and carbonate sand

Sharp Point shallow valley at end of transect

Banksia praemorsa & Adenanthos sericeus closed scrub

Fine-to-medium, grey, humic quartz sand with a small carbonate fraction.

Little Beach supratidal flat wetland and adjoining paluslope

Juncus kraussii grading to Baumea spp sedgeland with emergent tall shrubs of Callistachys sp South Coast.

A thin layer of sandy peat (i.e. medium white quartz sand in an organic matrix )

Little Beach dune Species- rich heath inc. Melaleuca thymoides, Anarthria scabra and Cyathochaeta equitans

Medium-to-coarse, white quartz sand.

Goode Beach- Mistaken Island foredune

Adenanthos sericeus tall open shrubs over *Pelargonium capitatum and naturalized alien herbs and grasses.

Fine, white, quartz sand with small fine black mineral sand fraction

Goode Beach- Mistaken Island mid slope granite outcrop with shallow soils

Patchy Verticordia plumosa low shrubs with emergent Anthocercis viscosa, geophytes & annuals.

Very fine peaty quartz sand

Goode Beach- Mistaken Island lower slopes of dune –shallow sand over granite

Darwinia diosmoides heath with Needhamiella pumilo and Stylidium repens

Fine- to- medium humic quartz sand

Goode Beach- Mistaken Island dune crest

Melaleuca thymoides heath with Anarthria scabra

Medium-to-coarse, white quartz sand.

The sand of the perched dune immediately inland of the supratidal flat at Little Beach and the perched

dune above the gneissic slope at the Goode Beach transect was a medium-to-coarse white quartz sand. The

upper layer of the sand from these two locations contained a significant proportion of dry organic debris.

The sand of these dunes therefore appeared superficially grey in contrast to the pure white of the

foredunes. In the wetland at Little Beach, medium-sized white quartz grains were a minor component of

the fine black organic matter that formed the framework and thus this material was classed as a sandy peat.

In contrast to this, in the shallow moist soils on the gneissic slope at the Goode Beach transect, very fine

white quartz sand particles were more abundant than the much smaller, interstitial, mud-sized organic

Page 4: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea

43particles. Therefore this material was classed as peaty sand. Fine to medium quartz sand coated with

organic particles (i.e. humic sand) comprised the shallow soil just above the outcropping rock in this

transect. The shallow soils of the high limestone-capped plateau adjacent to the cliffs at Sharp Point was

the only material in the Albany transects that contained some carbonate grains but, as in the above, the

predominant material was fine-to-medium white quartz sand.

Vegetation and flora of the Albany transects 1. Sharp Point The beginning of the Sharp Point transect in the Torndirrup National Park was situated on the edge of a

high plateau truncated by tall cliffs facing the Southern Ocean near the Sharp Point lookout (Figs 26, 27 &

28). From the relatively flat area of limestone pavement on the seaward edge of the plateau, there was a

gentle upwards slope north to the crest of low irregular-shaped perched dunes. Beyond this was a gentle

downwards slope to the northern end of the transect.

A species-rich low heath (less than about 30cm in height) with perennial sedges dominating the herb layer,

was found on the shallow soils of the limestone pavement on the plateau at the start of the transect. This

vegetation commonly included Melaleuca pentagona, Templetonia retusa (Cockies Tongues), Pultenaea

quaerita, Gahnia sp. Headland (G.J Keighery 8501) and Desmocladus austrinus. Also common were

Acacia littorea, Acrotriche cordata, Asteridea nivea, Brachyscome iberidifolia, Euphrasia collina subsp.

tetragona, Haloragis digyna, Hibbertia grossulariifolia, Isotoma scapigera, Logania fascicularis, a local

variant of Lysinema ciliatum (Curry Flower), Opercularia spermacoccea, Pimelea ferruginea, Spyridium

marjoranifolia, Stylidium fasciculatum, Thomasia triphylla, Velleia trinervis, Westringia dampierii and

Wurmbea dioica. Although the transect was only surveyed from the safety of the cliff plateau, it was

apparent that similar vegetation to that found at the start of the transect also extended for a distance down

the cliff face.

The deeper sands on the crest of low irregular perched dunes nearby were dominated by a closed scrub of

Agonis flexuosa (Peppermint) less than 3m in height with Scaevola nitida and a distinctive assemblage

including Gahnia sp. Headland (G.J Keighery 8501), Gyrostemon sheathii, Lepidosperma pubisquameum,

Lepidosperma gladiatum, Lomandra micrantha subsp. micrantha, Sollya fusiformis, Spyridium

globulosum, Westringia dampierii and occasionally Melaleuca ringens and a broad leaf form of Logania

vaginalis.

Page 5: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea

44A more dense but very species-rich heath to a maximum of about 1.5m in height was prevalent on the

gentle slope to the north of the transect. This heath was dominated by the silver-foliaged Adenanthos

sericeus subsp. sericeus (Albany Woollybush) and Spyridium globulosum (Basket Bush) with Acacia

littorea, Acrotriche cordata, Desmocladus austrinus, Gahnia sp. Headland (G.J Keighery 8501),

Melaleuca pentagona, Olearia axillaris, Templetonia retusa and Westringia dampierii. The shallow valley

at the end of the transect was a closed scrub of Banksia praemorsa and Adenanthos sericeus to about 4m in

height with a sedge and rush understorey including Desmocladus austrinus.

Page 6: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea
Page 7: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea
Page 8: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea

472. Goode Beach (near Mistaken Island) The foredune colonizers at the Goode Beach transect (Figs 29, 30, 31& 32) were *Euphorbia paralias,

*Cakile maritima and *Tetragonia decumbens. Adenanthos sericeus subsp. sericeus (Albany Woollybush)

first recruited within 4 metres of the start of this colonizing vegetation. Further from the beach, Adenanthos

sericeus formed an open scrub to 3.5 m in height. This zone was dominated by naturalized alien taxa

(including some very vigorous weeds) although a significant indigenous flora was also present. Common

taxa included *Avena barbata,*Bromus diandrus, Caladenia latifolia, Carex preissii, Carpobrotus

virescens, Conostylis aculeata subsp. aculeata, Daucus glochidiatus, Desmocladus sp., *Ehrharta

longiflora, Ficinia nodosa, Hibbertia cuneiformis, Lepidosperma gladiatum,*Pelargonium capitatum,

Pimelea clavata, Poa poiformis, Rhagodia baccata,*Senecio elegans and an undetermined alien Iridaceae

species.

Towards the landward margin of the foredune, Agonis flexuosa subsp flexuosa formed a closed scrub to

5m in height with a thick understorey of tall shrubs and sedges dominated by Hibbertia furfuracea and

including Pimelea clavata, Hibbertia cuneiformis, Clematis pubescens, Lepidosperma pubisquameum,

Desmocladus sp., Opercularia hispidula and Parietaria debilis. Occasional low mallees of Eucalyptus

staerii were present at the western edge of the Agonis scrub. Here the construction of a gravel track has

probably eliminated most of the vegetation of the transition between the dune and the rocky outcrop

originally present in this zone of the slope. The remnants of this included Adenanthos sericeus, Spyridium

globulosum, Lepidosperma pubisquameum, Leucopogon cucullatus, Leucopogon revolutus, Hibbertia

furfuracea and Calytrix acutifolia.

The base of the gneiss outcrop slope was a heath about 1m in height of Darwinia diosmoides with an

annual herb and geophyte understorey. Common associates were Andersonia sprengelioides, Cryptostylis

ovata, Drosera pallida, Eutaxia cuneata, Needhamiella pumilo, Phyllangium paradoxum, Pimelea rosea,

Stylidium spathulatum and Trachymene pilosa. There was very little vegetation over most of the central

zone of the outcrop except patchy low clumps of Verticordia plumosa subsp. plumosa and Pimelea

imbricata with emergent sparse shrubs of Anthocercis viscosa subsp. viscosa and moss swards with

annuals and geophytes including Chamaescilla corymbosa, Drosera ?erythrorhiza, Philydrella pygmaea,

Siloxerus filifolia, Stylidium inundatum, Stylidium perpusillum and Thelymitra flexuosa. On the upper

margin of the outcrop the vegetation was similar to that at the base of the outcrop i.e. a Darwinia

diosmoides heath.

Page 9: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea

48The slope of the dune above the rock outcrop was a species- rich heath less than 1 m in height

dominated by Melaleuca thymoides, Lysinema ciliatum and Anarthria scabra. It also included

Adenanthos cuneifolius, Amperea sp., Andersonia caerulea, Astroloma baxterii, Bossiaea praetermissa,

Chorizema glycinifolium, Darwinia diosmoides, Dasypogon bromeliifolius,

Jacksonia spinosa, Lomandra sonderi, Lyginia imberbis, Petrophile rigida, Schoenus caespititius,

Stylidium repens and Xanthosia rotundifolia subsp. rotundifolia.

Page 10: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea
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Page 12: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea
Page 13: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea

523. Little Beach The vegetation of the Little Beach transect (Figs 33 &34) immediately adjacent to the beach at about 1m

above mean sea level was a closed sedgeland of Juncus kraussii with the rhizomatous herb Samolus repens

and occasional Apium prostratum and Villarsia parnassifolia. The rocks truncating the beach at both ends

were fringed by Sarcocornia quinqueflora. The sedgeland was more species- rich further upslope so that at

about 2m above sea level Baumea juncea, Baumea acuta and Baumea preissii subsp laxa were also

present.

The vegetation of the wetland between about 2.5m to 3m above sea level was a relatively species- rich

sedgeland with tall open shrubs of Callistachys sp. South Coast to about 2.5m in height and Hypocalymma

cordifolium subsp. cordifolium to about 1.1m in height. Associated with these were Baumea juncea,

Baumea acuta, Baumea preissii subsp laxa, Gahnia trifida, Lepidosperma striata, Meeboldina scariosa

and Schoenus sp. South Coast. On the upper margin of the paluslope wetland about 3.5m above mean

sealevel (apart from Callistachys sp. South Coast and Hypocalymma cordifolium) there were also large

clumps to 2m in height of Lepidosperma effusum and Acacia myrtifolia, Agrostocrinum stypandroides,

Anarthria prolifera, Baumea rubiginosa, Boronia spathulata, Dampiera leptoclada, Hibbertia

cunninghamii, Leucopogon carinatus, Patersonia lanata, Sphaerolobium fornicatum, Taxandria

juniperina, Thelymitra flexuosa and Velleia trinervis.

The middle and upper slope of the dune facing the beach was a heath less than 1m in height dominated by

Melaleuca thymoides, Anarthria scabra and Cyathochaeta equitans. Associated with this were Adenanthos

cuneifolius, Bossiaea praetermissa, Chorizema glycinifolium, Dasypogon bromeliifolius, Gompholobium

scabrum, Loxocarya cinerea, Lyginia imberbis, Lysinema ciliatum, Jacksonia spinosa, Melaleuca striata,

Petrophile rigida, Pimelea longifolia subsp. longifolia, Scaevola striata, Schoenus caespititius, Stylidium

repens and Xanthosia rotundifolia subsp. rotundifolia.

Page 14: Sharp Point (Torndirrup National Park) Goode Beach ... · a small, shallow, rocky-floored embayment that is sheltered on the seaward margin by a line of rocks just above mean sea