Cape York Peninsula tropical savanna explained

Cape York Peninsula tropical savanna
Map:Ecoregion AA0703.svg
Biogeographic Realm:Australasian
Biome:tropical and subtropical grasslands, savannas, and shrublands
Border1:Carpentaria tropical savanna
Border2:Einasleigh Uplands savanna,
Border3:Queensland tropical rain forests
Area:121,160
Country:Australia
State1:Queensland
State2:Torres Strait Regional Authority
Coordinates:-13.5°N 142.6°W
Conservation:Relatively stable/intact
Protected:35,713 km² (29
Protected Ref:)[1]
Type:region
Cape York Peninsula
State:qld
Area:122564.57
Near-N:Torres Strait
Near-Ne:Coral Sea
Near-E:Coral Sea
Near-Se:Wet Tropics
Near-S:Einasleigh Uplands
Near-Sw:Gulf Plains
Near-W:Gulf of Carpentaria
Near-Nw:Gulf of Carpentaria
Near:Cape York Peninsula

The Cape York Peninsula tropical savanna is a tropical grasslands, savannas, and shrublands ecoregion in northern Australia. It occupies the Cape York Peninsula in Queensland, mainland Australia's northernmost point. It is coterminous with the Cape York Peninsula (code CYP), an interim Australian bioregion.[2] [3] [4]

Geography

The ecoregion covers the northern portion of the Cape York Peninsula, along with the adjacent Torres Strait Islands. The Coral Sea lies to the east of the peninsula, and the Gulf of Carpentaria is to the west. The ecoregion is bounded by the Carpentaria tropical savanna ecoregion to the southwest, Einasleigh Uplands savanna to the south, and Queensland tropical rain forests to the southeast.

The west of the region is dominated in the south by an extensive Tertiary sand sheet dissected by the drainage systems of the Holroyd Plain, the Tertiary laterite of the Weipa Plateau, and the low rises of Mesozoic sandstones, while the northern section consists of the Weipa Plateau together with extensive coastal plains along the Gulf of Carpentaria. To the east lie aeolian dunefields. Along the eastern margin the Coen-Yambo Inlier, which includes the Iron and McIlwraith ranges, has complex geology of volcanic, metamorphic and acid intrusive rocks. The subregion of the Battle Camp Sandstones, formed from deeply dissected plateaus, lies in the southeast of the region. The Laura Lowlands, composed of sands and silts and colluvial and alluvial clays, lies between the Coen-Yambo Inlier and Battle Camp Sandstones, in the catchment of the Normanby River.[5]

The northern end of the Great Dividing Range runs through the ecoregion, parallel to the east coast of the peninsula. 15 freshwater drainage basins or watersheds overlap the ecoregion. Rivers that drain eastwards to the Coral Sea include the Olive, Pascoe, Lockhart, Stewart, Hann, Normanby, Jeannie, and Endeavour, and the Jardine, Pennefather, Ducie, Wenlock, Watson, Archer, Ward, Holroyd, Coleman, and Alice rivers drain westwards to the Gulf of Carpentaria.[5] [6]

Subregions

In the IBRA system, Cape York Peninsula (CYP) has nine sub-regions:

IBRA regions and subregions: IBRA7
IBRA subregionIBRA
code
Area
acres
CYP01 2312126ha
CYP02 512498ha
CYP03 94367ha
CYP04 1444223ha
CYP05 504409ha
CYP06 1791228ha
CYP07 2848753ha
CYP08 2464074ha
CYP09 284780ha

Climate

The climate is tropical, humid or maritime, with rainfall varying from 1000 mm to 1600 mm, including some high-rainfall areas at high elevations.

Flora

Plant communities are diverse, and include woodlands, heathlands, sedgelands, mangroves, and vine forests (including both semi-deciduous vine forests on the eastern ranges and deciduous vine thickets on western slopes). In all 39 distinct vegetation types are recognised.[7]

The predominant plant community is eucalypt woodlands and savannas, which cover 64% of the ecoregion's area, with Darwin stringybark (Eucalyptus tetrodonta) as the dominant tree in 36% of the ecoregion. Open woodlands of Melaleuca spp. cover 15% of the ecoregion.[7]

Rainforests and vine thickets cover smaller areas, concentrated along the east coast, and represent 20% of Australia's total.[7] Rainforests and vine thickets are of several different types, which vary with climate and soils. Littoral rainforests and coastal vine thickets extend along the east coast southwards of Princess Charlotte Bay, including offshore islands like the Flinders Group. Characteristic species include beach cherry (Eugenia reinwardtiana) and Micromelum minutum.[8]

The Iron and McIlwraith Ranges are home to the most extensive rainforests and vine forests in the ecoregion, which grow on older metamorphic rocks on the eastern side of the escarpment. These include evergreen notophyll vine forests.[9] These forests have floristic affinities to New Guinea.[10]

Heathland of low-growing plants is common on nutrient-poor sandy soils formed from eroded granite, including large areas of the Iron and McIlwraith ranges.[11]

Most of the ecoregion's watersheds are relatively intact, home to freshwater aquatic species and often lined with dense riparian forests.[7]

Mangrove forests are found in the north east and along the estuaries on the coasts. 36 mangrove species are recorded on the peninsula.[7]

40% of the ecoregion's plant species are shared with New Guinea. There are also 330 bioregionally endemic plant species and five bioregionally endemic plant genera, including Wodyetia, Jedda, and Indagator.[10]

Fauna

Birds endemic to the Cape York Peninsula include the buff-breasted buttonquail (Turnix olivii), golden-shouldered parrot (Psephotus chrysopterygius), lovely fairywren (Malurus amabilis), white-streaked honeyeater (Trichodere cockerelli), and yellow-spotted honeyeater (Meliphaga notata).[12] Several species are native to both the northern Cape York Peninsula and New Guinea, including the palm cockatoo (Probosciger aterrimus), southern cassowary (Casuarius casuarius), yellow-billed kingfisher (Syma torotoro), Papuan pitta (Erythropitta macklotii), trumpet manucode (Phonygammus keraudrenii), magnificent riflebird (Ptiloris magnificus), fawn-breasted bowerbird (Chlamydera cerviniventris), and yellow-legged flycatcher (Kempiella griseoceps).[11] The ecoregion is on important migration routes for both land birds and seabirds.[7] [12]

The spotted cuscus (Spilocuscus maculatus) and giant white-tailed rat (Uromys caudimaculatus) are native to the ecoregion and to New Guinea.[7] The Cape York melomys (Melomys capensis) is a species of rat endemic to the ecoregion.[13]

Conservation and protected areas

Most of the ecoregion has infertile soil, which has limited the development of agriculture. Much of the ecoregion is used for livestock grazing, and overgrazing has degraded some areas. Introduced species, including feral pigs, cane toads, and invasive weeds, have endangered native species by predation, competition, and altering habitats. Non-Aboriginal settlers changed the ecoregion's fire regime, which has reduced and degraded some plant communities and habitats. Several Important Bird Areas in the ecoregion, including Lilyvale, Morehead River, Lockerbie Scrub, and Iron and McIlwraith ranges, are threatened by property and tourism development.[7]

34.29% of the ecoregion is in protected areas. Protected areas in the ecoregion include Endeavour River National Park, Possession Island National Park, Mount Cook National Park, Alwal National Park, Jardine River National Park, and Annan River (Yuku Baja-Muliku) National Park. Protected areas on Aboriginal land include Apudthama National Park, Batavia National Park, Biniirr National Park, Bromley (Ampulin) National Park, Bromley (Kungkaychi) National Park, Cape Melville National Park, Daarrba National Park, Errk Oykangand National Park, Juunju Daarrba Nhirrpan National Park, Kulla National Park, Kutini-Payamu (Iron Range) National Park, Lama Lama National Park, Melsonby (Gaarraay) National Park, Muundhi (Jack River) National Park, Ngaynggarr National Park, Olkola National Park, Oyala Thumotang National Park, Rinyirru (Lakefield) National Park, Wuthathi (Shelburne Bay) National Park, and Kaanju Ngaachi Indigenous Protected Area.[3]

Notes and References

  1. Eric Dinerstein, David Olson, et al. (2017). An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm, BioScience, Volume 67, Issue 6, June 2017, Pages 534–545; Supplemental material 2 table S1b. https://doi.org/10.1093/biosci/bix014
  2. Web site: Map of Ecoregions 2017. Resolve. en. August 20, 2021.
  3. Web site: Cape York Peninsula tropical savanna. Digital Observatory for Protected Areas. en. 13 August 2024.
  4. Web site: Cape York Peninsula tropical savanna. The Encyclopedia of Earth. en. August 20, 2021.
  5. https://wetlandinfo.des.qld.gov.au/wetlands/facts-maps/ Wetland Summary—facts and maps
  6. Environment Science and Services (NQ) (1995). "Stage 1 Overview Reports: Overview of Current Resources, Land Uses and Issues". Cape York Peninsula Land Use Strategy, Department of the Premier, Economic and Trade Development, Brisbane, and Department of the Environment, Sport and Territories, Canberra.
  7. https://www.oneearth.org/ecoregions/cape-york-peninsula-tropical-savanna/ Cape York Peninsula Tropical Savanna
  8. Web site: Littoral rainforests and coastal vine thickets of eastern Australia . Department of the Environment, Water, Heritage and the Arts, Australian Government . March 2009 . Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) policy statement – Nationally threatened species and ecological communities guidelines . 20 June 2023.
  9. Neldner, V.J and Clarlcson, J.R. (1995). 'Vegetation Survey and Mapping of Cape York Peninsula'. (Cape York Peninsula Land Use Strategy, Office of the Co-ordinator General of Queensland, Brisbane, Department of the Environment, Sport and Territories, Canberra, and Queensland Department of Environment and Heritage, Brisbane.
  10. Wannan, Bruce (2014). Review of the phytogeography of Cape York Peninsula: a flora that illustrates the development of the Australian sclerophyll biota. Australian Journal of Botany 62, 85-113. https://doi.org/10.1071/BT13295
  11. BirdLife International (2024) Important Bird Area factsheet: Iron and McIlwraith Ranges. Retrieved 18 August 2024.
  12. BirdLife International (2024). Endemic Bird Areas factsheet: Cape York. Retrieved 14 August 2024.
  13. Burnett, S & Winter, J. 2016. Melomys capensis. The IUCN Red List of Threatened Species 2016: e.T13117A22420633. https://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T13117A22420633.en. Accessed 20 August 2024.