For most of the Western Australian Museum’s Aquatic Zoology team, a recent expedition to Gascoyne Marine Park delivered a treasure trove of weird and wonderful creatures from depths of up to 5000m below sea level.

The Museum’s Head of Aquatic Zoology Dr Lisa Kirkendale, Curator of Crustacea and Worms Dr Andrew Hosie, Curator of Fishes Dr Glenn Moore and technical officers Corey Whisson and Ana Hara were part of a multidisciplinary scientific team to uncover some of the strangest creatures ever found off Western Australia’s coast: dark-purple sea urchins that sparkled with iridescent blue light; blind, fuchsia-pink 50cm-long scampi; translucent, white-fleshed squid exquisitely studded with multi-coloured shining “jewels” and a tiny clingfish were amongst the plethora of specimens carefully preserved during the expedition.

Slit shell. Courtesy CSIRO, Frederique Olivier 

For Dr Kirkendale who specialises in molluscs the discovery of a spectacular “slit” shell (an ancient gastropod that evolved about 500 million years ago) in the Indian Ocean was like finding a unicorn! The few surviving modern species are all deep-sea dwellers and are particularly rare in the Indian Ocean – yet one individual was found that has an enormous and iridescent sculptured shell the size of two fists.

Witnessing the behaviour of a deep-sea scampi species was a highlight for Dr Hosie: captivating footage showed the scampi sitting in a complex burrow with what appear to be multiple openings rather than just a simple hole. The stunning fuchsia-coloured scampi was seen sitting at one entrance with its finely toothed claws cocked open ready to ambush unwary prey. This species was found at a depth of 1000m and, at 50-60cm, is bigger than the typical lobsters found in seafood stores.

For Dr Moore, the remarkable diversity of fish species was astounding but, among the hundreds of species they recorded, a single tiny clingfish was one of his highlights. This stunning little pink and yellow fish only grows to around 3 centimetres long and, as far as we know, survives life in the deep water by hiding in empty snail shells on the seafloor.

Sunlight does not reach the deep sea and the pressure of water is truly immense: both these characteristics shape the deep-sea environment and the creatures that live there. The aim of the expedition, which was led by CSIRO, was to document as much biodiversity as possible across all depths within the Marine Park. CSIRO research vessel (RV) Investigator, from which the team worked, was equipped to tow nets and underwater camera and video equipment to collect specimens, images, and footage at a depth of 50m – 5,000m.

Deep-sea cucumber (Enypniastes sp.). Courtesy CSIRO, Frederique Olivier

Scientists from WA Museum, CSIRO, Tasmanian Museum and Art Gallery and Museum of Zealand Te Papa Tongarewa spent an exhaustive month working around the clock on 12-hour shifts in the close quarters of RV Investigator. Since returning from the expedition, the Museum’s Aquatic Zoology team started preparing for the detailed identification of the specimens; including rehousing specimens to museum standards for long-term storage and comparing them with known species to determine which are new to science.

Gascoyne Marine Park is part of a network of 60 Australian Marine Parks in Commonwealth waters which are managed by Parks Australia.

This research was supported by CSIRO, Parks Australia and a grant of sea time on RV Investigator from the CSIRO Marine National Facility.

Information for this article has been extracted from Australian Geographic’s article Delivered from the Deep, which can be read in full here.