This super rare squid is a deep-sea mystery. We recently spotted not 1, but 5, in the Great Australian Bight

Osterhage et al., Author provided

Hugh MacIntosh, Museums Victoria and Deborah Osterhage, CSIRO

The mysterious bigfin squid has been spotted in Australia’s waters for the first time. My colleagues and I from the CSIRO and Museums Victoria detail the encounters in our new research, published today in Public Library of Sciences ONE.

There have only been about a dozen bigfin squid sightings worldwide over the past two decades. Ours happened more than two kilometres below the ocean’s surface in the Great Australian Bight, off the coast of South Australia.

For many people, the phrase “deep-sea squid” may conjure up images of the giant squid, Architeuthis dux, or krakens with huge tentacles swimming in inky black water.

But there are dozens, if not hundreds, of other species of deep-sea squid and octopus (both members of the class Cephalopoda) that are just as mysterious.

First encounters with a slippery individual

For years, one of the only ways to sample the deep sea was to trawl the sea floor with nets. This often damaged the soft bodies of deep-sea organisms beyond recognition. These mangled specimens are then difficult to identify and reveal little to nothing about the creatures.

Fortunately, newer technologies such as remotely-operated vehicles (ROVs) equipped with high-definition cameras are letting scientists see species as they’ve never seen before — offering deeper insight into their shapes, colours and behaviours in the wild.

Magnapinna is a member of the Cephalopoda class, which includes octopuses and cuttlefish.
Osterhage et al., Author provided

The enigmatic bigfin squid, Magnapinna, is one case in point. When scientists first described the species in 1998, all they had to go by were some damaged specimens from Hawaii.

The most distinctive feature of these specimens were the large fins (at the very top of the body), which gave the squid its name. Years later, scientists exploring the deep Gulf of Mexico with ROVs realised they had come across Magnapinna in the wild.

They discovered that in addition to its distinctive fins, its arms had incredibly long filaments on the tips, making the bigfin squid unlike any other encountered.

These delicate filaments, which are mostly broken off in collected specimens, give Magnapinna an estimated total length of up to seven meters!

In 2001, scientists exploring the seafloor off Oahu, Hawaii, captured footage of a bigfin squid estimated to be between four and six metres long.

Mysterious critters and where to find them

But despite deep-sea ROV surveys becoming more common, Magnapinna has remained elusive.

The handful of sightings have been as far apart as the Central Pacific, North and South Atlantic, Gulf of Mexico and Indian Ocean. This suggests a worldwide distribution.

Yet, the big fin squid had never been seen in Australian waters. That is, until recently, when our team took part in a major research project to better understand the biology and geology of the Great Australian Bight, through the Great Australian Bight Deepwater Marine Program.

On the CSIRO’s research vessel Investigator and charter vessel REM Etive, we surveyed as deep as five kilometres below the water’s surface. Using nets, ROVs and other camera equipment, we recorded hundreds of hours of video footage and uncovered thousands of species.

On one dive, as we watched the video feed from cameras far below us, a wispy shape emerged from the gloom. With large undulating fins, a small torpedo-shaped body and long stringy limbs, it was unmistakably Magnapinna. We yelled and brought the ROV to a halt to get a better look.

The meeting lasted about three minutes. During this time we managed to use parallel laser pointers to measure the squid’s length — about 1.8 meters — before it swam away into darkness.

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In total, we recorded five encounters with Magnapinna in the Great Australian Bight. Based on the animals’ measurements, we believe we recorded five different individuals: the most Magnapinna ever filmed in one place.

Most previous records have been of single Magnapinna, but our five squid were all found clustered close to each other. This might mean they like the habitat where they were found, but we’ll need more sightings to be sure.

Unexplained behaviours

The footage we captured has offered new information about Magnapinna’s ecology, behaviour and anatomy.

Previously, Magnapinna has been seen many meters off the sea floor in an upright posture, with arms held wide and filaments draping down. We’re not sure what the specific function of this behaviour is. It might be a way to find prey — akin to dangling sticky, sucker-covered fishing lines.

On our voyage, we saw the squid in a horizontal version of this pose, just centimetres off the sea floor, with its arms and filaments streaming behind. Again, we don’t know whether this behaviour is for travelling, avoiding predators or another method of searching for prey.

If you look at this photo carefully, you can a bigfin squid with its arms spread wide, and its filaments as faint lines stretching away to the bottom right.
Osterhage et al.

One near-miss with a camera gave us a very closeup image of Magnapinna which showed filaments that appeared to be coiled like springs. This may be a means for Magnapinna to retract its filaments when needed, perhaps if it wanted to avoid damage, or reel in something it caught.

Until now, only one other cephalopod, the vampire squid (Vampyroteuthis infernalis), has been known to coil its filamentous appendages this way.

A close encounter just centimetres off the seabed shows the squid in a horizontal posture, with its arms spread and filaments dragging behind. Curiously, some of the filaments appear to be coiled like springs.
Osterhage et al.

We have learned more about the mysterious bigfin squid. But until we have more sightings, or even an intact specimen, questions will remain.

One thing we do know is ROV surveying has great potential to enhance our understanding of deep-sea animals. With so much of the ocean around Australia yet to be explored, who knows what we’ll see coming out of the gloom next time?

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Hugh MacIntosh, Research Associate, Marine Invertebrates, Museums Victoria and Deborah Osterhage, Marine Scientist, Oceans and Atmosphere, CSIRO

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Piglet Squid

Squid team finds high species diversity off Kermadec Islands, part of stalled marine reserve proposal

This squid belongs to one of the families (Histioteuthidae) that is highly diverse but was not previously recorded from the Kermadecs.
Richard Young, CC BY-SA

Kat Bolstad, Auckland University of Technology and Heather Braid, Auckland University of Technology

Squids and octopuses could be considered the “parrots of the ocean”. Some are smart, and many have complex behaviours. And, of course, they have strange, bird-like beaks.

They are the subject of ancient myths and legends about sea monsters, but they do not live for decades. In fact, their high intelligence and short lifespan represent an unusual paradox.

In our latest research we have discovered several new species that have never been reported from New Zealand waters. Our study almost doubles the known diversity for the Kermadec region, north of New Zealand, which is part of the proposed, but stalled, Kermadec–Rangitāhua ocean sanctuary.

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More than we bargained for

Collectively, squids and octopuses are known as cephalopods, because their limbs attach directly to their head (cephalus). Our team studies cephalopods in our part of the world – the waters between Antarctica and the most northern reaches of New Zealand, the Kermadec Islands – as well as further afield.

Our first inkling of an impressive regional diversity came as we began to open boxes of frozen cephalopod samples at the National Institute for Water and Atmospheric Research (NIWA). These animals had been collected during a deep-sea survey voyage to the Kermadec Islands to better understand the region’s marine biodiversity. Members of the AUT Lab for Cephalopod Ecology and Systematics (ALCES), also known as the “squid lab”, had come to identify and examine them.

As we gently defrosted each specimen, we marvelled at their perfect suckers, iridescent eyes, and shining light organs. We noticed that many species were rare among New Zealand collections. There were some familiar faces, but also some we had only rarely or never encountered before in our local waters. Some were known from neighbouring regions; others, we suspected, might be entirely new to science.

We examined them, photographed each one, took small samples of muscle tissue for DNA analysis, and preserved them for additional work in the future. Then we set about systematically comparing our observations with what had previously been reported in New Zealand waters. And we were in for a surprise.

Doubling known diversity

Among the 150 cephalopod specimens that were collected, we identified 43 species, including 13 species that had not been previously found anywhere in New Zealand waters. Three entire orders – the taxonomic rank above family, which is the level at which, for example, egg-laying mammals split off from all other living mammals – had not been reported from this region: “Bobtail squids” (sepiolids), “comb-fin squids” (genus Chtenopteryx, order Bathyteuthoidea), and myopsid squids (coastal squids with eyes covered by a cornea).

We extracted DNA and obtained sequences for the species that had been seen for the first time in New Zealand waters. This allows us to compare them with individuals from other regions of the world. These included the strange tubercle-covered “glass” (cranchiid) squid Cranchia scabra, and the little “ram’s horn squid” Spirula spirula.

Examples of squid specimens collected recently from the Kermadec Islands Ridge: A) Histioteuthis miranda, B) Heteroteuthis sp. ‘KER’ (likely new to science), C) Chtenopteryx sp. ‘KER1’ (likely new to science), D) Leachia sp. (likely new to science), E) Pyroteuthis serrata, F) Enoploteuthis semilineata. Scale bars: 5mm.
Images by Rob Stewart/Keren Spong, CC BY-ND

Five species appear likely new to science, across a number of families with colourful common names such as “strawberry” and “fire” squids (Histioteuthidae and Pyroteuthidae, respectively). These individuals were genetically distinct from all other specimens that had been previously identified and sequenced (by us or others). Their physical appearances will now need to be compared in detail with other similar-looking species in order to fully evaluate their taxonomic status.

In total, 28 of the species we encountered had not previously been reported in the Kermadecs. This brings the total number of species in the region to at least 70. Of these, half are not known to occur elsewhere in New Zealand waters.

Kermadec–Rangitāhua Ocean Sanctuary

The Kermadec Islands, north-north-east of New Zealand, represent a diverse and nearly pristine environment. The region includes (among other habitats) a chain of seamounts and the second-deepest ocean trench in the world.

Currently, the Kermadec Islands region is on a tentative list of UNESCO World Heritage Sites. A small proportion of the area is already protected by an existing marine reserve, which extends 12 nautical miles around each of five islands and pinnacles.

This map shows New Zealand’s Exclusive Economic Zone (EEZ) in light grey, the existing Kermadec Islands marine reserve in dark grey, and the proposed Kermadec–Rangitāhua Ocean Sanctuary outlined in black.
Heather Braid, Kat Bolstad, CC BY-ND

The proposed Kermadec–Rangitāhua Ocean Sanctuary would extend the protection to 200 nautical miles and protect 15% of New Zealand’s ocean environment. It would be among the world’s largest marine protected areas.

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We strongly support the establishment of the proposed sanctuary, especially since most of the cephalopod taxa newly reported by this research are deep-sea species whose habitat is not protected by the existing marine reserve.

Although the creation of the sanctuary is supported by most political parties, New Zealand First, which is part of the government coalition, opposes it. So does the fishing industry because fishing would be banned. It is possible that the sanctuary might be created with a lower level of protection than originally proposed (with some fishing still permitted), but the government has reached an impasse.

If the Kermadec–Rangitāhua ocean sanctuary were to be established, it would protect habitats that are used by over half of the known squid and octopus biodiversity in New Zealand waters, including 34 species that have so far only been reported from the Kermadec region.

Kat Bolstad, Senior Lecturer, Auckland University of Technology and Heather Braid, Postdoctoral Research Fellow, Auckland University of Technology

This article is republished from The Conversation under a Creative Commons license. Read the original article.