The Cape Agulhas lighthouse museum

Cape Agulhas lighthouse
Cape Agulhas lighthouse

The ground floor of the Cape Agulhas lighthouse is devoted to a lighthouse museum and curio shop/tourist information centre. The museum is small, but well worth investigation if you’re a lighthouse buff.

Poster display about the Cape Agulhas lighthouse
Poster display about the Cape Agulhas lighthouse

There is a large number of posters on display, covering the history of the Agulhas light and the surrounding area, as well as lighthouses around the world. There is also a selection of lenses and other historical lighthouse and rescue equipment.

Display of historical lighthouse paraphernalia
Display of historical lighthouse paraphernalia

Entry to the museum is included in the lighthouse entrance fee.

Documentary (BBC): Arctic with Bruce Parry

1422966653_ARCTICfMuch of my recent Arctic obsession has been historical, with a related interest in the hostile environment that has stymied (and killed) so many explorers over the centuries. Bruce Parry is a British documentarian (didn’t know that was a thing, but it seems fun) who seems to be dearly loved and some kind of national institution to the Brits. After watching this five-episode BBC series on the Arctic and its people, we could understand his charm.

Parry visits people living in Siberia, Greenland, northern Canada, Alaska, and the far north of Norway. He throws himself into their activities – whether rounding up reindeer, hunting for seals on the ice, fishing in Alaska (I had some serious lifestyle envy at this point), or racing up mountains. He is sensitive and respectful, and seems to forge genuine bonds with the families he visits.

The common thread that marks the lives of many of the tribes and peoples’ that Parry visits is that climate change, and the encroaching changes wrought by the pace of modern life, are challenging their traditions and lifestyles. Having lived sustainably off the land for generations, these people’s movements, traditions and futures are now circumscribed by all sorts of interventions from modern society. Not least of these is a lack of understanding of and respect for how they live.

Tony and I found much to discuss – for example, after the episode covering a traditional whale hunt in Alaska. Is there a difference between Japanese industrial whaling and an Inuit community’s subsistence hunting  for a couple of whales a year, done with reverence, prayers, and gratitude for the whale, whose bones will be scraped clean by polar bears after the entire carcass has been distributed in the village? Is it possible to kill an animal as large as a whale, humanely? Is all whaling wrong? These are difficult questions but it is worth grappling with them. As my friend Tami has exhorted me in the words of Rilke (in a different context, admittedly), “live the questions!

The series was filmed over the course of a summer, during which time much of the usual ice that marks the Arctic landscape was absent. The look of the landscape initially puzzled (and disappointed) me – without the icy covering, everything looks quite barren and gravelly!

You can get the dvd here (South Africa), otherwise here or here.

Bookshelf: Rescue Warriors

Rescue Warriors: The US Coastguard, America’s Forgotten Heroes – David Helvarg

Rescue Warriors
Rescue Warriors

Much of this book reads like one of the Reader’s Digest “drama in real life” stories that I used to devour from the magazines that my granny brought us when she came to visit. (She’d also bring a packet of Sparkles or Cadbury Eclairs.)

Journalist, activist and former war correspondent David Helvarg (who also wrote Saved by the Sea and 50 Ways to Save the Ocean) spent two years embedded with various branches of the US Coastguard in order to experience their work.

I had naively thought that the US Coastguard, despite being funded by the government, and despite their website having a .mil for military domain name, was just a slightly larger, more financially flush version of South Africa’s National Sea Rescue Institute (NSRI).

I was wrong. The mandate of the US Coastguard is to enforce maritime law (this is its primary difference from the NSRI) as well as to perform search and rescue operations. Viewers of the Deadliest Catch series will be familiar with the rescue work of the Coastguard in extremely challenging conditions. As a result of its law-enforcement mission, the Coastguard uses weapons and provides a lot more military-style training than you’d expect from a pure rescue operation. The Coastguard falls under the department of homeland security and operates cutters (with guns), icebreakers, small boats, helicopters, and other aircraft.

Helvarg’s conservationist tendencies shine through in several parts of Rescue Warriors, and he does not shy away from confronting the aspects of the Coastguard that he finds problematic. His contention is that the Coastguard receives far less publicity than it deserves. This book goes some way towards bringing attention to the individuals who have saved tens of thousands of people during Hurricane Katrina, via water evacuation during the September 11 attacks, and in countless other less well-known emergency situations.

This is a gripping read which I thoroughly enjoyed. I was amazed by the amount of funding and equipment that the Coastguard has at its disposal compared to the NSRI, even though the organisation is actually badly underfunded, especially when considered relative to the rest of the United States war machine. I was also impressed by the egalitarian approach that draws many women to join the Coastguard and enables them to rise in its ranks. The Coastguard made all its jobs available to women in 1977, something which other branches of the military have not yet done.

You can get a copy of the book here (South Africa), here or here.

Colour fronts in False Bay

Colour front seen from Sunny Cove on 27 November 2015
Colour front seen from Sunny Cove on 27 November 2015

Perhaps you have wondered what causes the patterns of strange coloured water in False Bay during the summer months. Perhaps you have dived in it, and wondered why sometimes you can’t see your hand in front of your face! Wonder no more – I am here to help.

Colour fronts

Frequent visitors to and residents of the shores of False Bay will observe that at certain times of the year, the ocean is marked by bands and arcs of sharply contrasting coloured water. This phenomenon is known as a colour front. In oceanography, a front is the interface or boundary between two separate masses of water. In this case, the water masses are easy to discern, because they are of different colours. There are usually other characteristics of the water on each side of the front that differ, too. Fronts are either convergent (the water masses are moving towards each other) or divergent. The presence of marine debris (like pieces of kelp) at the front boundary suggests that it is convergent.

Causes of colour fronts in False Bay

Prior to 2005, there was much conjecture about the causes of these fronts (including the usual pollution bugbear), but little evidence to support any of the theories. By sampling, the fronts were found not to be caused by pollution, or by plankton blooms in the surf zone. It was known that a colour front was most likely to occur in False Bay after a period of southerly or south easterly wind lasting a few days. October and November seem to be prime months for the phenomenon.

When a large, obvious colour front arose near Simon’s Town in November 2005 with milky green water on one side, and darker blue-green water on the other, researchers from UCT and IMT sprang into action, sampling the water on each side of the boundary so that they could measure its characteristics. Speed is of the essence in these situations; colour fronts can disappear quickly. The one in the picture below is busy decaying – notice the smudged boundary.

Colour front in north western False Bay on 13 November 2014
Colour front in north western False Bay on 13 November 2014

Measurements revealed that the milky green water overlaid the clearer, bluer water, down to a depth of 11-12 metres (this will vary from front to front). The milky water did not extend to the ocean floor.  Scuba divers around the Cape Peninsula will be familiar with the experience of diving through two or more layers of water, with varying turbidity (clarity) and temperature! (Here is picture of Tony and Christo diving near Oudekraal in the Atlantic that shows what the boundary between two layers of water can look like.)

The researchers found that the milky coloured greenish water was full of fine, almost neutrally buoyant particles of calcium-rich sediment. The green-blue water contained much less calcium, but relatively more silicon, which would suggest the presence of diatoms (a kind of phytoplankton – you can think of them as teeny tiny plant-like organisms) or sand in the water. The origins of the calcium-enriched sediment in the milky water are interesting: one source is from the shallows (less than 30 metres deep) of north western corner of False Bay, where the ocean floor is made up of rocks that are rich in calcium carbonate (such calcrete and limestone), some areas covered by a thin layer of sand.

Milky-white water near Swartklip on 29 November 2014
Milky-white water near Swartklip on 29 November 2014

The second probable origin for the particles of calcium-rich material is the interface between the sea and the land at the northern end of False Bay. The cliffs at Wolfgat/Swartklip at the head of the bay are made of calcrete, and at Swartklip the beach narrows to the extent that the cliffs erode directly into the water when the sea is high. Strong southerly winds create a wide (of the order of one kilometre) surf zone at Muizenberg and Strandfontein; a spring tide also adds to ideal conditions for the generation of a colour front.

The temperature of the milky water was found to be slightly (0.4 degrees Celcius) higher than the green-blue water. This measurement will also vary from front to front. The researchers speculate that the temperature difference could be because the milky water originated in the surf zone, which is shallower and therefore warmer, or because the high concentration of suspended particles in the milky water caused greater absorption of heat from the sun.

Colour front at Smitswinkel Bay on 24 October 2014
Colour front at Smitswinkel Bay on 24 October 2014

Summary

Here’s the tl;dr: strong southerly and/or south easterly winds, perhaps coupled with spring tide conditions, set up a very wide surf zone along the northern end of False Bay, which disturbs the sediment on the ocean bottom and drives the waves further up the beach than usual. Particles of buoyant calcium carbonate from the sea floor and eroded from the cliffs at Swartklip are lifted up into the water column, changing its colour to a milky-green shade. Wind-driven circulation patterns in the bay push the front from its original location in a southerly direction, towards Simon’s Town.

What to do?

Contrary to what your friends on social media may claim, not all colour changes in the ocean around Cape Town can be attributed to a giant sewerage plume. Hardly any of them can, in fact. In summer, the reason for the ocean looking green, red or even brown is likely to do with a plankton bloom of some description, or related to suspended sediments (as in this case) or other naturally arising material in the water. Instead of using this as an opportunity to become hysterical on the internet, how about celebrating the incredibly dynamic system that we can observe, living near the ocean? Drive up a mountain next to the ocean and take in the spectacle from on high. Dip your face in the water and see what it does to the viz. Take some pictures for posterity. And – if you don’t know what’s causing it – try to find and question someone who does know, like a scientist, or consult a good non-fiction book, to find out some facts.

If you’d like to read more about colour fronts in False Bay, take a look at this scientific paper (pdf), which I used as source material for most of this post. The paper is called A Prominent Colour Front in False Bay: Cross-frontal structure, composition and origin

Bookshelf: Frozen in Time

Frozen in Time: The Fate of the Franklin Expedition -Owen Beattie & John Geiger

Frozen in Time
Frozen in Time

Depending on whether you’ve followed my advice (who am I kidding) and read Franklin’s Lost Ship or The Man Who Ate His Boots, this book could either be a spoiler or constitute a fairly neat wrapping up of the loose ends and methods used to discover the fate of Sir John Franklin’s vanished 1845 expedition to the Canadian Arctic to search for the Northwest Passage.

Owen Beattie is a Canadian forensic anthropologist (a real one) who exhumed the bodies of three members of Franklin’s expedition who died and were buried on King William Island in the Arctic. Beattie’s team visited the island in 1984 and 1986 to work on the exhumation, examination and reburial of the three men. Buried in the permafrost, the bodies were remarkably well preserved (that’s a picture of one of them on the book’s cover).

Frozen in Time describes Beattie’s search for evidence about what led to the death of the men on the expedition, as well as providing a historical context for their search. The rigors of working in the Arctic – even in summer – and the historical, biological and cultural insight that can be obtained from the examination of dead bodies makes this a gripping read. You can read it as a stand-alone account of the Franklin expedition and its grim ending – no prior knowledge is required. Canadian writer Margaret Atwood’s introduction provides a beautiful interface between history, science and the deeper truths about ourselves that are revealed by the imperative to explore the Arctic.

Not everyone agrees with Beattie and Geiger’s thesis about what killed the men – if you’re still reading my Arctic ramblings, check out the argument put forward here.

Get a copy here (South Africa), here or here.

Cape Agulhas lighthouse

View of Cape Agulhas lighthouse from the seaward side
View of Cape Agulhas lighthouse from the seaward side

The Cape Agulhas lighthouse is the most visually pleasing lighthouse that I’ve visited so far. Tony and I visited it while we were staying at De Hoop last September.

View of Cape Agulhas from the top of the lighthouse
View of Cape Agulhas from the top of the lighthouse

Cape Agulhas was named by the Portuguese from their word for needle. During the 1500s, when they were plying Southern Africa’s coastline, the magnetic declination in the area was approximately zero, meaning that there was no deviation between true and magnetic north, and the compass needle pointed to true north.

The door at the top of the tower
The door at the top of the tower

(Technical sidebar: Cape Agulhas lay on an agonic line during the 1500s. An agonic line is a line on the earth’s surface along which the magnetic declination or variation is zero. Earth’s magnetic field slowly changes, and with it the positions of the north and south magnetic poles. For this reason, the variation between true and magnetic north at a point on the earth changes slowly over time. You can examine a map of historic declination over the last 400-odd years here – if you scroll it back to 1590 you can see the green line through Cape Agulhas.)

The lighthouse is within walking distance of the southernmost tip of Africa inside the Agulhas National Park, and was built on land donated by Michiel van Breda, a local landowner (for whom Bredasdorp was named). Van Breda had experienced the trauma of shipwrecks along the stretch of coastline on his farm, with hundreds of dead bodies washing up after ships foundered on the rocky shores in rough seas. The shipwreck museum at Bredasdorp commemorates many of these wrecks.

The lens inside the lantern house
The lens inside the lantern house

The lighthouse was commissioned on 1 March 1849. It has a 7.5 million candela light that emits one flash every 5 seconds and has a range of 31 nautical miles. The lighthouse tower is 27 metres high, with a focal plane 31 metres above sea level. The tower is made of limestone with a white lantern house. By the 1960s the tower had deteriorated to such an extent that the lighthouse was temporarily decommissioned (its job performed in the interim by an aluminium tower), and restoration was undertaken. It was recommissioned in 1988.

View of L'Agulhas
View of L’Agulhas

The lighthouse is open to the public (also on weekends, which is unusual for a South African lighthouse) and contains a museum and a gift shop on the ground floor. The view from the top is well worth the climb.

If you love lighthouses, you need to get hold of Gerald Hoberman’s Lighthouses of South Africa.

Bookshelf: Franklin’s Lost Ship

Franklin’s Lost Ship: The Historic Discovery of HMS Erebus – John Geiger and Alanna Mitchell

Franklin's Lost Ship
Franklin’s Lost Ship

Since reading The Man Who Ate His Boots, my obsession with the history of the exploration of the Canadian Arctic has not abated. You can expect to be troubled by many more Arctic book reviews and related material from me.

This book is a well-illustrated account of the discovery of one of Sir John Franklin’s ships, HMS Erebus, in the waters north of Canada. You will (may?) recall that Franklin’s entire expedition – some 130 men and two ships – disappeared while searching for the Northwest Passage, on a journey begun in 1845. Parts of the mystery of their disappearance, and what happened to them, have since been resolved, but until late 2014 ago no sign of either of the two ships had been found.

If you are interested in the story, this relatively short book both recounts what is known of Franklin’s expedition and the subsequent searches for him and his men, as well as detailing the recent discovery of HMS Erebus by a team of Parks Canada archaeologists. There are underwater photographs and side-scan sonar images showing the ship standing upright in about eleven metres of water. It’s an excellent complement to Anthony Brandt’s more detailed history, but can equally well be read on its own, as an account of history spanning 160 years, meeting technology from the present.

Some sections – such as the extensive and laudatory passages devoted to former Canadian prime minister Stephen Harper and his reflections on the discovery – were puzzling to me. I was pleased to see how much credit was given to the indigenous Canadian people and their maps and oral histories for their role in locating the ship. Their accounts of the fate of Franklin’s men, and clues as to the location of his ships, proved crucial in the discovery of HMS Erebus, despite being immediately disregarded by Franklin’s contemporaries.

You can get a copy of the book here (South Africa), otherwise here or here.

Sea life: Southern elephant seals

Elephant seal busy moulting
Elephant seal busy moulting

A juvenile southern elephant seal (Mirounga leonina) has been seen around the Cape Peninsula for a couple of months. Almost every year solitary individuals are spotted resting on our shores, but they remain uncommon visitors and always cause a bit of excitement. Their usual habitat is subantarctic and Antarctic waters, including the islands belonging to South Africa and New Zealand, the Falkland Islands, and select parts of continental South America. They feed in Antarctic waters and spend winter down by the pack ice, insulated by tremendous layers of blubber. They are expert divers and can hold their breaths for two hours at a stretch.

Elephant seal cooling off with damp sand
Elephant seal cooling off with damp sand

Southern elephant seals are the largest seals, with the males (which can weigh up to 4,000 kilograms and grow to six metres in length) as much as six times larger than the females, which weigh 400-900 kilograms and grow to between 2.5 and 3 metres in length. At sexual maturity the males develop a big, inflatable rubbery snout (more correctly called a proboscis). This gives them their name, thanks to its rudimentary resemblance to an elephant’s trunk.

Juvenile seals are weaned and leave their mothers when they weigh about 120 kilograms. At this point they are just under a month old. This particular seal, which we saw hauled out near Cape Point, was at least two metres long already, and was busy moulting. During this time, the seal loses (as you can see in the top image) and regrows its fur. Some of its blood supply is diverted towards its skin to facilitate hair growth. Moulting happens during summer, and takes about a month (because it happens so suddenly, it is called a “catastrophic moult”). During this time the seals stay out of the water and possibly do not eat. Lying on the beach, well insulated with blubber, can cause them to overheat, so the seal we saw was flicking damp sand over his (or her) back to cool down.

As far as their conservation status goes, they are listed as of least concern on the IUCN Red List. They are probably helped by living so far from human activity, although they are still affected by plastic pollution, boat strikes and the like.

If you do see one of these animals, don’t be a jerk. Keep your distance (at least 20 metres) and don’t completely surround the seal. This ensures the animal stays happy and calm, and sets an example for others who may not have your good attitude, excellent education and experience with animals. Also, seals can move surprisingly fast on land, and an elephant seal is almost certainly going to weigh a lot more than you do. Tony took these pictures from a respectful distance, with his 150-500 zoom lens.

Article(s): The Longform guide to sea creatures (some holiday reading!)

Here are some holiday reading recommendations – not too taxing, not entirely insubstantial – to enjoy while lounging under an umbrella by the pool or waiting for a flight to board. You will probably enjoy them because they’re about marine life, and I assume that if you didn’t have a passing interest in the ocean, you wouldn’t be reading this blog.

Octopus at Pyramid Rock
Octopus at Pyramid Rock

Longform is a website that provides reading recommendations – usually (as the name suggests) long form stories, not restricted to a particular range of topics. I am a subscriber to the Longform newsletter, and lately a user of their iPad app.

The Longform guide to sea creatures is a short list of juicy long articles whose common thread is that they focus on marine animals. I’ve shared some of them with you already – Killer in the Pool and Moby Duck being the most notable. Others are about giant squid, octopus, tuna, whales, and the Loch Ness monster. It’s a page worth bookmarking, should you anticipate requiring a couple of hours of thoughtful, fact-checked, well researched reading on the subject of marine life.

You can find the list of Longform sea creature articles here, and a mostly overlapping but slightly different version on Slate.com, here. (The advantage of the Slate list is that you can send the articles to your Kindle, to read later.)

 

A visit to the Bredasdorp Shipwreck Museum

Exterior of the shipwreck museum
Exterior of the shipwreck museum

In the centre of Bredasdorp, the sleepy town in the Overberg that you will likely pass through on your way to De Hoop, Cape Agulhas, Arniston or any of the surrounding areas, is a museum devoted to shipwrecks. Tony and I paid it a visit while we were staying at De Hoop in September last year, and enjoyed it immensely. The museum is situated in an old church, and spills over into two other adjacent historical buildings.

Artefacts from SS Maori
Artefacts from SS Maori

The shipwreck museum contains artefacts from a wide variety of wrecks – many of them from the coastline between Danger Point and Cape Agulhas, but others from further afield (including our neck of the woods)! There is a display about SS Maori, including some of the pottery that was in the mixed cargo on the vessel.

Interior of the shipwreck museum
Interior of the shipwreck museum

In addition to cargo items (including a vast array of bottles spanning a few hundred years of history), there are figureheads, binnacles, ship’s bells, cannons and anchors – the latter located outside in a beautiful garden behind the museum. The ship’s wheel of SS Kadie, wrecked at the mouth of the Breede River, is also on display. The Arniston, Queen of the Thames, and Birkenhead wrecks also feature prominently. Familiarising yourself in advance with some details about the most prominent wrecks of the Overberg region will enrich your visit.

A separate garage-like structure (technically known as the Old Coach House), accessible over a tiny river bridge in the garden, contains a historical fire engine, carriages and other vehicles and implements of everyday life from a century ago. There is even a rocket-propelled breeches buoy apparatus, used from shore to rescue shipwreck survivors.

Tony for scale!
Tony for scale!

Another building included in the museum facilities is a fully furnished historical Overberg home called the Old Parsonage – when we walked through, there was even a (real live) cat having a cool nap on a hand-sewn quilt in one of the bedrooms.

Reminder about regulations pertaining to shipwrecks
Reminder about regulations pertaining to shipwrecks

Since we’re thinking about shipwrecks, a reminder about South African legislation pertaining to historical wrecks is timely!

If you’re in the area the Bredasdorp Shipwreck Museum is definitely worth a visit. Opening hours and contact details can be found here. The entry fee is minimal.