Parakeet Paradise [Rottnest Island] EarthCache

🛰 Parakeet Paradise
[Rottnest Island] 🌏

Welcome to Rottnest Island (Wadjemup)'s first Earthcache!

This EarthCache has been placed with the permission of the Rottnest Island Authority.

Little Parakeet Bay is a small piece of paradise situated on the northern coastline of Rottnest Island. The purpose of this EarthCache is to take you on a short journey to discover some of the island's prominent and less obvious geological features.

Acknowledgement of Country

We acknowledge the Traditional Custodians of the Land on which this cache is located, the Whadjuk People of the Noongar Nation, and their continuing connection to Country and community. We pay our respect to Elders past, present and emerging.

Their land stretches from Victoria Plains to the north, Toodyay in the south, eastwards as far as west of York, and includes Rottnest Island (Wadjemup). It also extends towards the southern coastal frontier to the vicinity of Pinjarra, includes the eastern and northern tributaries of the Swan River and runs to beyond Mount Helena in the hinterland.

We recognise the Aboriginal and Torres Strait Islander people as the First Australians and we are committed to honouring their unique cultural and spiritual relationships to the land, waters and seas, and their rich contribution to society.

Help Protect the Environment of Rottnest Island

Rottnest Island is an 'A' Class Reserve and therefore the natural environment is protected by Legislation, including all flora and fauna.

• The sand dunes and limestone must not be climbed upon, damaged or interfered with. They are part of a fragile ecosystem, which is at risk (particularly at Little Parakeet Bay) and it is being monitored by the Rottnest Island Authority.
• You are not permitted to destroy, remove or bring any flora or fauna on or off the Island.
• Feeding or interfering with the wildlife, including exotic species is prohibited. Feeding of wildlife can result in their death, disease or over population.

Are you a CITO Crusader?

Every geocache presents us with a perfect opportunity to CITO (Cache In Trash Out).

Please help clean up some litter while you're here visiting this cache and attach a photo to your log to show off your much appreciated efforts!

Finding this Geocache

Instructions and How to Verify Your Find

Once you have visited all Waypoints and complete the EarthCache requirements you can post your find, as per the EarthCache guidelines.

You will, however, need to verify your find by sending me a message via the Message Center with the GC code and cache name (GC55T4W Parakeet Paradise) on the first line and provide your answers to the questions listed below, otherwise your log may be removed. To do this, visit my profile and click on Send Message.

Adhering to the EarthCache guidelines, please be careful not to include any detail in your log or photos that may assist others in answering the questions without actually visiting the sites and carrying out the fieldwork.

Make sure you stick to the designated paths and leave no trace. Please do not interfere with the geological material, vegetation or wildlife – the tasks can be completed without the need to damage the environment.

OPTIONAL: You are encourage to take a photo of yourself, as well as any other members of your party, with GPS in hand with the Indian Ocean in the background and another one in front of the Limestone outcrop on the beach. Upload the photo to your log.

EarthCache Questions:

1) Name three biotic factors that have impacted the limestone in the area.

2) What is the most prominent biotic factor at Little Parakeet Bay? Explain your answer.

3) Name two abiotic factors that have impacted the limestone in the area.

4) What type of limestone is exposed at Little Parakeet Bay (Tamala, Rottnest or Herschell Limestone)?

5) Describe the look and feel, as well as the noticeable characteristics, of the limestone at Little Parakeet Bay.

6) Do biotic or abiotic factors generally have a greater influence on the amount and type of sediments deposited in each layer of the limestone? What effect does this have on the limestone?

FTF honours: starlemusique.

Earth Sciences Lesson: Geological Material

Rottnest Island was once connected to the mainland but separated around 7,000 years ago when the sea level rose, creating a chain of islands on the continental shelf opposite Perth, Fremantle and Rockingham. These islands are formed of limestone rocks with a thin covering of sand.

The three major geological units of Rottnest Island are Holocene coastal sand dunes (less than 10,000 years old), Holocene swamp and lake deposits and Pleistocene Tamala Limestone and lime sand dunes (10,000 years to about 1.5 million years old). The coastline of the island is characterised by alternating rocky headlands and bays. Most of the bays, including Little Parakeet Bay, have sandy beaches that back onto sand dunes.

The island is predominantly built of Tamala Limestone (late Pleistocene to early Holocene dune limestone) with a thin intercalation of Rottnest Limestone (late Pleistocene coral-reef limestone) overlain by a thin Herschell Limestone (middle and late Holocene shell beds).

The Tamala Limestone is a unit of eolian calcarenite, composed of wind-blown shell fragments and variable amounts of quartz sand. The characteristics of Tamala Limestone are large-scale cross-bedding, marking successive dune slopes.

Rottnest Limestone is a late Pleistocene unit of coral-reef limestone and associated shelly, gastropod-rich limestone. Herschell Limestone is a unit of Holocene marine shell beds with interbedded lime sand, ranging from friable to strongly cemented, and is subdivided into two members known as the lower Vincent Member and the Upper Baghdad Member.

(Sources & further reading: Guidebook to the Geology of Rottnest Island by Phillip E. Playford).