Windswept and interesting

A fine spring day at the beach – although windy – can often bring pleasant surprises. If you don’t go, you don’t know.

This eastern osprey (Pandion haliaetus cristatus) swept in over Lighthouse Beach, Ballina, holding a large, wriggling, very much alive fish in its talons. It alighted on a dead tree and proceeded to peck at its lunch. The bird was struggling to stay balanced in the brisk breeze.

Osprey with freshly caught fish meal

We often see them scouring the waters for food at Ballina and raising chicks in nests they’ve built on tall poles specially made for them by the local council. We are lucky to have them – they are getting rarer in other areas. Their conservation status in NSW is ‘vulnerable’.

Happy snappering

Beachcombing is satisfying when you come across something unusual, isn’t it?

And you get a second dose of endorphins when you find out what it is. At least, I do.

So when Andrew found this strange thing on the sand at Ballina, I sent off photos to the Queensland Museum, who kindly identified it for me.

It was hard, but not as hard or cold as a stone, and smelt faintly of fresh fish.

It turns out to be the protuberance on top and towards the rear of the head of a large  Australian snapper (Chrysophrys auratus, previously known as Pagrus auratus). This one has separated from the rest of the skeleton.

Chrysophrys auratus (photo by Pengo, Wikimedia Commons). Note the distinctive “head hump”.

It is partially eroded on one side but you can see where it was attached to the skull on the basal stem, as illustrated in the two skeletons below.

Part of the skeleton of a large snapper, Chrysophrys auratus, showing the protuberance at the top and rear of the head. (Photo by Museum Victoria, Creative Commons licence)

Skeleton of snapper, Chrysophrys auratus (photo by Pengo, Wikimedia Commons). The protuberance at the top of this one is rather large.

The function of such a hump seems to still be a mystery. According to  Dr Ben Diggles:

The enlargement of particular areas of fish bones is known as hyperostosis, a fancy word that simply means “above normal bone growth”. The condition is not new; it has been observed in fossilised fish and was first described in modern times as far back as 1655. Today, hyperostosis occurs in at least 96 species of mainly marine fishes worldwide in 22 families, but for Australian recreational fishers it’s most commonly seen in snapper, trevallies, and threadfin salmons. …

       The location of the bones that are affected and how they grow appear to be fairly consistent and predictable within a species. …

      The cause of hyperostosis is unknown, mainly because it occurs mainly in older wild fish and has never been reproduced under controlled laboratory conditions. However, science has been able to rule out some of the possibilities, putting the most common of the urban myths to rest in the process. The condition occurs in both male and female fish, and is certainly not due to injury or repeated bumping of affected areas during feeding. I have examined several affected fish (snapper and king threadfin) and can confirm the opinions of other scientists that the hyperplastic bony tissue growth is not cancerous, nor does it seem to contain any pathogens which might indicate it is caused by a contagious disease-like condition.

Current thinking suggests that because hyperosteosis only occurs in certain fish species which display consistent and characteristic patterns of bone overgrowth, the condition probably has a genetic basis. Certainly it has been found that some sub-populations of Australian snapper are more likely to exhibit hyperostostis than others, which would be consistent with a genetic cause.

Hence, for those species of fish affected by hyperostosis, a genetically encoded hormonal or biochemical anomaly affecting calcium storage or bone remodeling, [which] may be triggered by certain environmental or nutritional conditions, cannot be ruled out. Alternatively, other scientists favour a purely genetic cause, pointing out that fish with prominent hyperostosis tend to be bottom feeders, and that increases in bone mass would be beneficial for these species by providing negative buoyancy, which would assist them during bottom foraging activity.

Which is a detailed way of saying “nobody knows”, but it’s fun to speculate.

Ballina is a fishing centre so my “hump” may have come from one of the boats, commercial or otherwise.

I must go down to the sea again, to look for more mysteries.

The other victims of the flood

The magnitude of the Lismore floods is truly hard to comprehend until you drive through town and see the mud stains high on houses, and remember that many were flooded well over their roofs. The huge stinking piles of wrecked goods – furniture, clothing, possessions – made me cry as I drove through town on the way to the ocean. There is going to be a lot of PTSD. The videos on social media were bad enough, but seeing it in real life brought it home. I am thankful that damage to my own place was minimal.

Lismore has always been a flood area, a fact well-known to the First Nations people who lived here (and still live here) before the white settlers. The CBD is in the bottom of a geographical bowl and you can see from the 1889 map below the many creeks that drain into it, forming the Wilsons and Richmond rivers. The Great Scrub (aka the Big Scrub) no longer exists except in small remnants – it was cut down for timber and to create space for first sheep and then dairying. After the forests were cleared, roads were built, eventually lessening the need for river transport. Many of the outlying towns and villages that appear on a modern map didn’t exist at that time.

The Richmond River was then the only practical transport. If a ship was too big to make it all the way to Lismore  from ports on the coast, people and goods from Brisbane and Sydney were offloaded onto smaller boats at, say, Ballina, and these would make their way up the Richmond River, stopping at smaller settlements on the way. Lismore was built where the boats finally docked and was a very busy town in the early days of white settlement.

From Frederick Chudleigh Clifford (1889) “Richmond River District of New South Wales. New Italy. A brief sketch of a new and thriving colony, etc. [With a map.]” Publisher: C. Potter; Wikimedia Commons

The enormity of the flood caused dire problems not just for human inhabitants. Wildlife and hundreds of livestock were drowned – we’ll never know the full extent. One cow became famous for travelling 150 km south from her original herd along the riverside.

Great quantities of fresh water stormed down the catchments and into the Richmond River, pushing over trees and dragging them, fishes and vegetation out of the mouth at Ballina. The massive gush of fresh water would have killed many saltwater fish, too, as we witnessed on Lighthouse Beach. I was going to ask the Queensland Museum for IDs, especially of the very large fish washed up, but they are busy with their own clean up at the moment, so IDs will have to wait.

The council had pushed the debris up the beach and the smell wasn’t too bad at first. As the day heated up, the fishes began to swell and smell. We spent an hour or so there, but retreated before being too overwhelmed. Here are a few shots of what we found.

The 5c piece under the jaw of the fish gives scale.

I’m not sure what the structures within the mouth (below) are – gills? I imagine the spiky bits could be for holding prey so it won’t get away while being swallowed. If anyone knows, please tell me.

  People should keep their dogs from eating porcupine fish like the one below. They are toxic and will kill dogs that eat them.

Porcupine tish – toxic even when dead

I managed to retrieve the porcupine fish’s jaws.

Jaws of porcupine fish
Inside view of porcupine fish jaws

People should keep their dogs from eating porcupine fish like the one two photos above. They are toxic and will kill dogs that eat them. The Smithsonian website says:

Startled porcupine fish suck in air or water to inflate their bodies, becoming a prickly balloon-like shape to defend themselves from predators and some contain a neurotoxin a thousand times more potent than cyanide in their ovaries and livers. They are also good at offense, crushing the shells of clams and other marine mollusks with beak-like jaws so tough that they are preserved as fossils to be discovered millions of years later.

https://www.si.edu/newsdesk/releases/comparing-jaws-porcupine-fish-reveals-three-new-species

There were no sharks, rays or eels. Perhaps they escaped to the depths.

Half a dozen silver gulls were poking about – I was surprised there weren’t more as it would be a veritable feast for them. Normally we’d see sea eagles and brahminy kites cruising above the waters for live fish, but perhaps they don’t scavenge. The turbulent water was an impenetrable brown so they couldn’t have seen anything worth eating.

Overnight, the crabs will come out and help themselves. In the meantime, maggots were already doing their best to clean up the corpses.

I’m sorry this is not a more cheerful post. But eventually the beach and ocean will return to their calmer and more pristine selves. Normally it’s a soothing and uplifting place to be.

Not right now.

Green sawfish

Lismore is in a state of shock and the clean-up is progressing. I’m so sorry for the trauma people have gone through in this, the worst flood in the Northern Rivers and South-East Queensland in white history. We had relatively minor damage at my place, but repairs are progressing. The media will show you pictures if you search for “Lismore floods” or similar on your favourite search engine.

The Lismore Museum’s ground floor was flooded and some items have been trucked to Brisbane for conservancy. Volunteers have taken other items away for cleaning and restoration. I wrote this piece about an exhibit for the next bulletin, but I think publication may be delayed for a while.

Here is a saw that was blunt, but still cut enough to get food for its owner. It’s the rostrum (nose extension) of what was probably a green sawfish (Pristis zijsrow), also called the dingagubba. The museum accessioned it in 1955.

Green sawfish rostrum

The green sawfish was a type of ray that used to be found in the estuaries of the Richmond, Clarence and Tweed rivers and in deeper waters offshore.

Alas, this species is presumed to be extinct in New South Wales. Numbers started dropping quickly in the 1970s due to entanglement in gillnets (now banned) and being bycatch in shallow-water prawn trawling. The saws were often cut off and kept or sold as trophies, and the fins sold for the sharkfish fin trade.

Green sawfish have been measured at up to 5 metres tip to tail, and are thought to have grown up to 7 metres. Females gave birth in a river mouth, and the young swam upstream to spend four or five years in freshwater before returning to the coast. The reproduction rate was slow, not helping to bolster the dropping numbers.

Our sawfish’s rostrum has 24 ‘teeth’ (actually modified scales) on one side and 21 on the other. It is 950 cm in length. Green sawfish did have real teeth in their mouths on the underside of their bodies. The fleshy part of the rostrum had pores that detected movement and electrical fields  ‒ all animals make a weak electrical field even if it’s only from their heartbeat, and seawater is an excellent electrical conductor ‒ so the animal was able to locate and crush crabs, shrimps and other small bottom-dwelling invertebrates, swallowing them whole. In deeper water, the sawfish used the rostrum to side-swipe shoaling mullets and stun them enough to gulp them down for food.

Live green sawfish in an aquarium; photo by Flavio Ferrari, Wikimedia Commons

An Australian citizen science project is underway to gather data on sawfish, so if you see one, dead or alive, whole or rostrum only, drop a note to http://www.sharksandraysaustralia.com. The organisation is keen to build up more information and the best resource is people on the ground or in the water – you!

“It’s worse than that, it’s dead, Jim”

That’s what ran through my head on seeing this sea urchin in a rock pool at Flat Rock, Ballina, yesterday (why I was thinking of Star Trek, I’ll never know). Its green tube feet were moving quickly, but it wasn’t going anywhere. The orange spines were also moving and it would normally be speeding (if you can call it that) across the sandy rock pool bottom on the tube feet. But this one had met its demise. What it had left for a nervous system was causing the movement –  if you want to know more about what’s inside, go here.

The underside shows, in the centre, the mouthpiece (called the Aristotle’s lantern), which it would have used to scrape algae off the rocks and move it inside the body for digestion.

This one had been thoroughly speared and its guts eaten by a bird, possibly one of the sooty oystercatchers or the eastern reef heron (Egretta sacra albolineatai, dark morph) that was poking its beak into the pools.

Various migratory birds were enjoying a rest or gleaning. They’ll be off to the northern hemisphere in autumn.

There was also a small octopus on its last legs, so to speak, looking very unhealthy in one of the pools. It was upside down, flailing its arms and couldn’t right itself, and when I carefully moved it right-side-up, it didn’t trundle off to shelter like they usually do. Perhaps it was at the end of its life – octopuses often last only a year or so.

All in all, a bit of drama on the rock platform in the hot summer sun.

UFOs identified

Unidentified Floating Objects can be a bit of a challenge to identify. By the time they reach shore and are washed up, features have often been pecked off or removed by wave action, or the creature has just rotted away and what’s left is a bit of a mystery. In the case of the latter, a rotting whale carcass washed up on a beach may sometimes be mis-identified as some sort of fabulous sea monster.

Hundreds, possibly thousands, of clear, stiff, gelatinous ‘medallions’ have been washing up at Ballina – and, it turns out, in many places along the east coast.

In my quest to find out what these are, I emailed Ceridwen Fraser, associate professor in the Marine Science Department at the University of Otago and author of a new book called Beachcombing.

In her book, I had noticed a photo of a salp, which looked somewhat similar, but she thought my critters were jellies. She kindly put me onto the Facebook post of Coolum and North Shore Coast Care, which says:

These jellyfish are a relatively new species called Aldersladia magnificus, a genus and species within hydromedusa and within the Aequoreidae family found in tropical and subtropical waters (Gershwin, L. 2006).

What causes these blooms to happen? There are multiple causes, some contributing factors are ‘Eutrophication, climate change, overfishing, and habitat modification’ (Qu CF, Song JM, Li N. 2014).
When washed up they appear to have no tentacles, but when seen in the water they have long tentacles that can retract. These tentacles can sting so please be careful whilst swimming at the moment. Don’t be too scared though, Jellipedia rates them as a 1/5 on their sting-o-meter.
 
they are … bioluminescent. If you head down to the beach at night time at the moment to a spot where there are plenty of them you will see for yourself.

In 2006, Lisa-Ann Gershwin identified the new genus and published a paper, ‘Aldersladia magnificus: A new genus and species of hydromedusa (Cnidaria: Hydrozoa: Leptomedusae: Aequoreidae) from tropical and subtropical Australia’, and if you want all the gritty details you can download it for free from here.

Thank you to Ceridwen for pointing me in the right direction. It’s great fun finding and tracking down things I haven’t seen before. Now I can add one more thing to my bucket list: a salp!

 

The sound of breath freezing

The sound of breath freezing is very much outside my experience. I’ve lived most of my life on the driest continent on Earth and some parts of it are very hot, so the concept intrigues me.  I first read about it in one of the many books I’ve been devouring on the polar regions. For the breath to freeze, the air temperature has to be much lower than I’ve experienced (which was pretty much 2ºC all day and ‘night’ in the 24-hour-light Arctic summer, and minus a couple of degrees in rare frosts at home). The lowest temperature recorded in Australia (not counting our bit of Antarctica) was -23C (-9.4F) in the Snowy Mountains in 1974.

Apparently the indigenous people of Eastern Siberia have the lovely phrase, ‘the whisper of the stars‘.

When the temperature drops below the mid-minus 50s Celsius, a soft whooshing sound can sometimes be heard, like rice or grain being poured. This noise is caused by the moisture in one’s own exhaled breath turning to ice crystals in the cold dry air.

The Weather Doctor, reporting on temperatures of -64C (-83F) in Canada, gives another description:

The freezing of one’s breath produced a continuous hissing sound similar to dry blowing snow, and a tinkle when the ice crystals hit the ground.

I cannot imagine what -50C would be like, let alone -64C, but there are plenty of people who choose to live in that world.

Ice cliff at the edge of a glacier, Svalbard. It will calve off one day with an almighty boom and wave.

Photo by Bruce Moore

Seeing so much ice and so many glaciers in Svalbard was hard to get my head around – I kept pinching myself to confirm I wasn’t dreaming. Sipping drinks in the comfortable bar of the ship, I could hear the popping of the ice cubes in the drink, taken from small floating chunks of ice  – that released air was very likely to be thousands of years old.

Of course, looking at photos is nothing like actually being there – you’re missing on out on the feel of very cold air in your nose and on your skin, the sounds (the screaming birds, the gentle hum and vibration of the ship and the waves lapping against the bow if we were moving, and the marvellous, deep silence underneath all that), movement, peripheral sights, smells (oh, how clean that air smelt!) – but the beauty cried out to be captured.

Before the trip, I thought of glaciers as pristine, white and glowing, but the reality can be very different.

The different colours indicate the contents of the ice. The brown is dirt that has been transported down with the glacier, scraped off the rock it has scoured over thousands of years. Clear ice has been compressed over thousand of years, squeezing out any air bubbles that would reflect light. White ice is the result of a top layer of snow, reflecting all colours of light so that we see white. Different shades of blue show the amount of impurities inside. Green indicates algal growth.

Close-up of Svalberg iceberg; photo by MG

As the ice melts, unique artistic forms emerge.

Photo by Bruce Moore

Photo by Bruce Moore

Photo by Bruce Moore

Photo by Bruce Moore

Photo by Bruce Moore

Photo by Bruce Moore

Photo by Bruce Moore

There’s a bunch of descriptive words in English for different forms of ice. Here’s how Jill Fredston puts it in her book Rowing to Latitude: Journeys along the Arctic’s Edge:

Saltwater begins to freeze at just over 28ºF [-2ºC]. It progresses from a stew of individual crystals to thicker slush, to a bendable layer that, when it thickens and whitens, is called first-year ice. Any ice that survives a summer of melt, in the process becoming bluer, denser, and less salty, is known as multiyear ice. Typically, this ice thickens to ten or twelve feet. More generally, any sea ice not fixed to the land is termed pack ice.  … Pieces of pack ice, called pans or floes, move in response to wind … In contrast, glacier icebergs … are driven primarily by current.

Bergy bits are floaters smaller than icebergs, and growlers are smaller than bergy bits. The terms go on and on.

Brash ice (small pieces broken down from larger chunks) on the left. Note the clean cut-off line on the right, probably because the sea temperature is higher there.

The various forms of sea ice are important for a number of animals. Seals haul out on it to rest and warm up between feeds, and polar bears rely on them (mainly ringed seals) for food. After hibernation in winter, bear continually roam the ice in search of whatever they can find – whale carcasses, sea birds, seals hauling out, people …

The questing bear is the cream bit in the middle.

This bear went after a bearded seal, but ringed seals are much easier to catch.

Bearded seal hauled out on ice

Photo by Bruce Moore

Photo by Bruce Moore

I’ve been reading up on ice, the properties of ice, its nature and its relationship to living things. It’s been studied extensively for several hundred years by both explorers or scientists, as well as thousands of years by indigenous people who must know it intimately to survive. I won’t bore you with stuff you can easily look up but I’ve been struck by one thing (well, many things, but this intrigued me).

It was once thought that not much lived under the ice (except fish and the things that ate them and that they ate), but that turns out to be very wrong. As divers and ROVs go down, they are finding more and more strange and wonderful creatures, such as shown here in Antarctica.

Not only do algae live on the undersurface of ice, but also small patches of bottom life. Barry Lopez tells how this can happen in his wonderful sequel to his wonderful Arctic Dreams,  called Horizon:

… in some spots a weak bottom current might eddy around a cluster of benthic creatures, rocks, and bottom sediments and come to a complete halt in some crevice or notch. Here, a few molecules of seawater might freeze. Over time this initially smaller platelet of frozen freshwater might expand (as seawater crystallizes into platelets, it squeezes out the sea salts that keep seawater from freezing at 32ºF), creating a growing matrix of freshwater ice crystals. (The specific gravity of freshwater allows crystals of it to float in seawater.) At some point the expanding mass of freshwater ice becomes large enough to exert an upward force sufficient to uproot a section of the bottom. This scrap of the benthic community continue to float upward until it lodges on the underside of the sea ice cover.

One day I almost swam straight into a dark basalt cobble floating in the water column in front of me. I assumed it was encased in freshwater ice, but I could find no angle of observation that made this apparent. Had I not learned what can happen in these very cold waters, I would have had to conclude that here in Antarctica, dens rocks float.

We have so very much to learn.

The world’s northernmost museum

I’ve mentioned before that I’m fond of museums. Having worked in a museum early in my career (a natural history one), and now volunteering in one (a historical one), I know how much effort goes into them. I couldn’t resist going to the one in Svalbard. There’s a mining museum in Ny-Ålesund, which strictly speaking takes the title of world’s northernmost museum (at 78.92 degrees latitude), but Svalbard’s is the northernmost general museum (in Longyearbyen, 78.22 degrees latitude).

It’s modern style and well set-out, and looks like it’s had lots of money thrown at it. It covers natural history, mining history, and sealing/whaling history. That last is the main reason people first came to Svalbard after it was discovered in 1596 by the Dutch explorer William Barentz – there’s no sign of indigenous people there. Archaeology in Svalbard consists mainly of hunters’ huts and coal mining machinery. The coal mines are being phased out, with only one mine working at the moment. There’s even a failed marble quarry. Here’s an article on industrial archaeology in the polar regions if you want to get into the nitty-gritty.

 

I was pleased to see exhibits on underwater life in addition to the larger, more well-known animals. In summer, upwelling currents bring tonnes of phytoplankton and zooplankton to the upper levels of the sea, creating a bonanza of food for animals who must stuff themselves silly to either survive the winter on site or migrate south. I was hoping to get a book on underwater life in the fjords, but had to wait until the Bergen aquarium to find one in English. There is a lot more life on the cold sea bottom that I imagined.

Translation: hard bottom fauna

Translation: pair of ice amphipods

I like these 18th century illustrations.

Coal mining was extremely hard work, horizontally in narrow channels carved by the miners themselves. Miners had to climb up the steep mountain slopes to enter the mine, then work long hours in poor conditions.

Artwork tribute to miners on the main street of Longyearbyen

‘Sykehus’ (sign on the left of the statue) means ‘hospital’

There’s only one working mine now, and the old mines have been left as they are. They’ll probably be preserved indefinitely in the cold climate where things take a long time to rot down (if they ever do). Imagine walking up to this one every day for long hours of back-breaking labour in all seasons (including -40 degrees C and blizzards).

Bronze tribute to miners in the main street of Longyearbyen

 

 

Modern coalmining here is now much safer and better paid – see this article (note that it is a 2007  article, but gives an idea of modern conditions).

The photo below shows a disused mine and the graveyard below it. The white crosses mark the graves, including those of several miners (numbers vary depending on which website but seven seems to be in the majority) who died in the 1918 Spanish flu outbreak. The graveyard stopped being used in the 1950s. Bodies don’t tend to stay buried in the ground (buildings also rise up, due to the melting and re-freezing of the permafrost, unless they have special footings), and don’t decompose due to the extremely cold temperatures. In 1998, researchers exhumed some corpses to see if there was any Spanish flu virus still alive. I haven’t been able to find anything definitive on whether they found the virus. One website says traces of the virus were found in one body. Another says only skeletons were found (despite many websites saying bodies froze in the permafrost and so would be preserved). Dead bodies, and dying people, are now flown to the mainland for burial there. There’s been talk of moving the cemetery due to avalanche risk.

Old mine and graveyard

This website says:

… after exhuming six of the seven bodies in Longyearbyen cemetery, Canadian medical archaeologists extracted their lung, liver, kidney, and brain tissue using a boring device for taking tree core samples. The genetic material of the 1918 flu, researchers found, was still there — bits of ribonucleic acid (RNA) fragmented in the bodies. Back in the laboratory, researchers cultured the bacteria clinging to lung tissue; still alive, they grew hardily when placed in nutrient broth and heated to body temperature.

So I’m a tad confused about what actually happened.

Alcohol restrictions are in force in Longyearbyen, as a left-over from the old mining days when there wasn’t much to do except drink, leading to fighting. Our German guide said much the same about winter and whiskey (he didn’t mention fighting, though). Residents are limited to a quota of either 24 beers or two litres of hard liquor a month, but wine purchase is unrestricted. There aren’t any taxes on alcohol, so it is quite cheap (especially compared to mainland Norway where I paid A$16 for a schooner of beer, normally A$5 at my local pub).

Our guide’s alcohol card

 

Any human artefacts (including what seems to be junk) from 1946 and before are designated cultural heritage sites and must not be disturbed. So intriguing old huts like these are definitely off limits. Look from afar but don’t touch.

It’s a shame that ugly old machinery spoils the illusion of a pristine wilderness, but removing it is probably in the ‘too hard basket’.

Industrial archaeology

I suppose one could consider it an ‘open-air museum’. There are no curators here, though.

Arctic trip – beluga whales

I’d seen a beluga whale (Delphinapterus leucas) only once before, and that was in the Atlanta aquarium in the United States. In the wild it’s a more holistic experience, although it’s impossible to see the whole of the animals unless they’re beached – you’re getting a sense of how they live and behave in the environment they are adapted to.

The whole group went on a zodiac cruise to see what was out there, and we were fortunate to come across four or five belugas in a pod.

The younger ones are grey, whitening with age to very white at adulthood (7-9 years old). They are not that big – like a large dolphin. The white colouration camouflages them against orcas, polar bears and people, which are the three main predators.

They are toothed whales and dive to about 20 m, although have been recorded much deeper, looking for fish, shrimp, squid, octopus, crabs, clams and suchlike.

Beluga whales, Svalbard; photo by Bruce Moore

Photo by Bruce Moore

Photo by Bruce Moore

There is no dorsal fin. (Having one would be awkward when they bump up against the underside of ice.) The ‘melon’ (of fatty tissue) on the head helps with echolocation and communication, and is unusual in that it changes shape while the animal makes sounds.

Beluga whale at the Atlanta aquarium. Photo by Greg Hume, Wikimedia Commons

They shed their skin every year, in spring, rubbing themselves against gravel on the shallow bottoms of estuaries to help remove it.

I was keen to see a unicorn (yes, they do exist), but apparently narwhals are very shy of ships, so unusual to see.

Narwhal pod (Monodon monoceros); photo by Dr Kristin Laidre, Polar Science Center, UW NOAA/OAR/OER_NOAA, Wikimedia Commons

It’s common for narwhals and belugas to hang out together, and hybrids have been seen, called, ugh, ‘narlugas’. Is ‘bewhals’ better? You be the judge.

Walruses suck!

They really do! Let me explain.

I’d only seen walruses (Odobenus rosmarus, ‘odobenus’ from the Greek meaning ‘tooth-walker’; they sometimes haul themselves out of the water using their tusks) in TV documentaries, a la David Attenborough. I think Taronga Zoo in Sydney has at least one, but seeing such animals in the wild is a very, very different experience and much to be preferred if you can.

Walruses, like the polar bear, seem adorable, but this is a slightly condescending attitude we may have only if we are temporary visitors, far removed from the realities of living with them, unlike the Inuit who have relied on the North American population for food, knives and other tools, and weapons, for generations. Like with the Inuit, respect is paramount, along with the recognition that these are wild, and so potentially dangerous, animals. There are no native peoples in Svalbard, but walruses’ tough skin and ivory were sought after by Europeans there until protection in 1952. Numbers are increasing, from pretty much nothing to about 2,000 now.

Walrus haul-out, Svalbard

We saw the steam coming off the walruses before we saw the colony.

 

In the zodiac we sneaked up very quietly, turning off the engine and paddling the past few dozens of metres so as not to disturb them, and kept more than the minimum 30 m away. The guide asked us to speak in whispers if at all. Of course, the enormous beasts saw us and a few swam out to investigate, coming right up to the zodiacs in some cases.

They are very social and like to touch each other (thigmotactic).

Photo by Bruce Moore
Photo by Bruce Moore


Photo by Bruce Moore

The red colouration is due to the expansion of capillaries on the skin, helping the walrus lose heat.

The tusks can grow up to 1 m, but can get broken off in male-male breeding battles. Females have tusks, too.

Long walrus tusks in the Oslo Natural History Museum

According to National Geographic:

Walruses use their iconic long tusks for a variety of reasons, each of which makes their lives in the Arctic a bit easier. They use them to haul their enormous bodies out of frigid waters, thus their “tooth-walking” label, and to break breathing holes into ice from below. Their tusks, which are found on both males and females, can extend to about three feet, and are, in fact, large canine teeth, which grow throughout their lives. Male walruses, or bulls, also employ their tusks aggressively to maintain territory and, during mating season, to protect their harems of females, or cows.

Walruses apparently don’t see terribly well (it wouldn’t make sense to rely on eyesight in any season except summer, and don’t need it when feeding), but can smell – to detect the approach of predators (like polar bears) and identify their young – and hear extremely well (noises up to a mile or 1.6 km away). The whiskers (vibrissae, which can grow up to a foot or 30 cm long but mostly break off in contact with the sea bottom) are very sensitive. Walruses mostly eat clams buried in mud, but also take worms, crabs and sea cucumbers on the sea floor, diving down to 10-50 metres, and have been seen to eat ducks and seals!

Now the sucky bit. They rummage around on the sea floor, using their flippers and squirting water out to clear the clams of mud. Then they literally suck the soft parts right out of their shells, leaving the empty shells behind. A 2003 paper, ‘Feeding behaviour of free-ranging walruses with notes on apparent dextrality of flipper use’, goes into quite a bit of detail, concluding, among other things, that walruses are mainly, err, right-flippered.

Walruses mouths create massive suction. Photo by Bruce Moore

The paper says:

Walruses (Odobenus rosmarus) are highly specialised benthic feeders feeding almost exclusively on bivalves, making them an important component of the benthic ecosystem. It is mainly the soft parts of the bivalves that are found in walrus stomachs, with pieces of shells seen only rarely. Almost 6400 bivalve siphons have been reported in a single walrus stomach …

The walruses showed four different foraging behaviours; removing sediment by beating the right flipper, removing sediment by beating the left flipper, removing sediment by use of a water-jet from the mouth and rooting through sediment with the muzzle. There was a significant preference for using right flipper over left flipper during foraging.

I rather liked this 1962 nature journal detailing an expedition to one of the Svalbard fjords.

The whole skeleton gives you an idea of the size.



Walrus illustration, Longyearbyen Museum

It was yet another awesome encounter in Svalbard.