Newsletter: Tow the line

Hi divers

Weekend dive plans

No diving

Dive conditions

Seasonal changes are one thing, but the conditions have been less than great for a while. Good diving days have been rare over the last six weeks. This weekend – again – is not too rosy from more than one angle.

Firstly, this week my tow vehicle decided to have a career change, so the boat has nothing to attach to. Secondly, even if I am able to wrest the panel van back from my wife, shore dives don’t look like a good option as there is a 2.5 metre, 16 second swell tomorrow. This grows to 4 metres on Sunday, and the swell goes somewhat southerly. This lingers on Monday, by which time the wind starts humping again.

The Jeep in happier days, at Hout Bay
The Jeep in happier days, at Hout Bay

Plan ahead

Please bear in mind, if you do head out to Simon’s Town this weekend, that the navy is running a simulated disaster/attack scenario from early on Saturday morning, and you should expect detours and delays. Plan accordingly!

regards

Tony Lindeque
076 817 1099
www.learntodivetoday.co.za
www.learntodivetoday.co.za/blog/

Diving is addictive!

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Article: Outside on acoustic sanctuaries for whales

Departing dolphins, and Christo
Departing dolphins, and Christo

Whales and dolphins make extensive use of sound to communicate. Some of the purposes of this communication may be to organise during a hunt, to socialise or to co-ordinate group movement.

The predominance of long-distance shipping as a cost-effective and efficient way to transport goods around the world has increased the amount of anthropogenic noise in the ocean to the extent that, in some parts of the world, populations of wild cetaceans struggle to make themselves heard in order to communicate with each other.

Outside Online describes a recent paper that proposes “acoustic sanctuaries” to protect cetacean populations of marine mammals off the coast of British Columbia in Canada. This is a fascinating idea, and need not be difficult to implement:

These quiet areas could be pain-free places for governments to formally institute quiet zones, the paper argues. Ships wouldn’t have to be rerouted, the authors note, they would simply have to continue avoiding sensitive areas.

Read the full article here.

To read more about acoustic communication between cetaceans, try this article, the book Listening to Whales by marine mammal scientist Alexandra Morton, or (for a touch of eccentricity) the book Thousand Mile Song.

Article: The Atlantic on finding whales by listening

Humpback whales
Humpback whales

Let’s stay with whales for a bit. I love tales of serendipity in science. My favourite Ed Yong writes for The Atlantic about a team using multiple (160, to be exact) hydrophones (underwater microphones) to listen for fish in the Gulf of Maine. They were able to visualise the locations of millions of herring; they also discovered that they could hear thousands of whale calls clustered in specific locations, mostly humpbacks, which are very vocal animals. But this was not all:

Each whale species calls within a certain frequency range and makes its own distinctive repertoire of sounds. Using this information, the team could look at their recordings and extract the locations of five huge filter-feeding species (the blue, fin, humpback, sei, and minke) and three toothed ones (sperm, pilot, and killer).

The team was able to visualise the spatial distribution of the whales, and scientists may be able to use the multiple-hydrophone technique to study  the interactions of predator and prey species.

Read the full article here.

Whale carcass reporting in Cape Town

Whale skull near the Thomas T Tucker
Whale skull near the Thomas T Tucker

The Environmental Resource Management Department at the City of Cape Town needs your help:

We would like to try and get to whale carcasses well before they wash ashore on our coastline to deal with them more effectively and efficiently. As ocean users, if you come across a whale carcass floating anywhere in False Bay or from Cape Point north to Silwerstroom Strand we would be most grateful if you could call, whatsapp or sms 083 940 8143 (available 24/7) with an approximate location and time of sighting.

Please could I ask that you also forward/share this email to as many friends, colleagues or groups that you are aware of that use the ocean as we would like as large a network of people as possible that could report sightings.

Save that number in your cellphone contacts, and do your bit for beach safety and, hopefully, for the environment, by reporting sightings of deceased whales before they reach the beach.

Ideally (environmentally speaking) dead whales should be left out at sea to be scavenged upon by marine life and then sink to the bottom and return their nutrients to the ecosystem. Unfortunately the prevailing summer wind direction in Cape Town (south easterly) generally brings any such carcasses onto the beach in False Bay. This is a hazard to human safety because of the co-incident inshore presence of great white sharks during the summer months. A dead whale is a great feeding opportunity for sharks, and its accompanying oil slick will be evident from miles away, potentially bringing in more sharks to investigate. This is why the City wants the opportunity to deal with whale carcasses before they reach your local swimming beach.

It’s timely to remember that while some cetaceans die and end up on the beach because of reasons such as ship strikes, ingesting plastic or other pollutants, or acoustic disturbances related to human activity, some of these animals also die of natural causes or illness unrelated to man’s impact on earth. Many times, scientists will examine the dead animal and be able to state what most likely led to its demise. While it is distressing to see any dead animal, and particularly strange and discomfiting to see a whale on shore, this is not necessarily confirmation that “the ocean is dying” or that we are “killing False Bay.” Sometimes it’s just the circle of life. Dead whales were an important source of nutrients and building materials to Strandloper communities long before industrial shipping plied the world’s seas.

For more on what happens to whales that die at sea (hint: it’s magnificent), check out this video. For more on the collision of dead whales and the urban environment, there’s this post about a whale on the beach in Fish Hoek, this one about a whale on the road in Cape Town, and this one about a stranded whale in the United States.

But I digress. Save this phone number: 083 940 8143, and tell your ocean-loving paddler, surfer, sailor, boater and diver friends to do the same!

Newsletter: Castles in the sand

Hi divers

Summer weather patterns and wind direction are sure taking their time heading off. This far into March and we have not yet had any spectacular diving. Well it has to change sometime, but I don’t think the time is this weekend.

Saturday looks good from a wind point of view, however the swell is supposed to peak at 4 metres on Friday afternoon with a 14 second period. That will make for  very surgy diving, and even deep dives will feel the 14 seconds. The swells don’t always arrive as predicted but this evening just before sunset it was already at 3 metres and starting to ruffle a few feathers.

Aaaaaaand tip!
Aaaaaaand tip!

Sadly, once again, I think we are set for a dry weekend. Sunday has more wind and less swell, and visibility will most likely be good out of Hout Bay but 15 knots of wind, 2-3 metre swells will not make for great diving. I have a sand dune at home so if you are at a loose end you are welcome to pop in and build a castle.

regards

Tony Lindeque
076 817 1099
www.learntodivetoday.co.za
www.learntodivetoday.co.za/blog/

Diving is addictive!

To subscribe to receive this newsletter by email, use the form on this page!

Newsletter: 70,000 wheels

Hi divers

Weekend dive plans

Saturday: Shore dives at Long Beach

The weekend looks quite rosy for change, and both Saturday and Sunday should be great. False Bay would be best on Saturday but on Sunday there are going to be approximately 70,000 wheels all trying to pass one another on the peninsula from really early until late afternoon. This is going to severely hamper diving opportunities around the peninsula, so you’re either going to have to get creative, or crack out the popcorn and a lawn chair and enjoy the Cycle Tour spectacle.

I am doing shore dives with students on Saturday, most likely at Long Beach. Let me know if you want to join us.

Clouds at Scarborough
Clouds at Scarborough

Be a good ocean citizen

The Department of Environmental Affairs has proposed 22 new Marine Protected Areas for South Africa. It only takes an email to throw your support behind this excellent development. Read this for more information.

regards

Tony Lindeque
076 817 1099
www.learntodivetoday.co.za
www.learntodivetoday.co.za/blog/

Diving is addictive!

To subscribe to receive this newsletter by email, use the form on this page!

Marine-related MOOCs from edX

As a fourth and final (perhaps) installment to our guide to ocean-related MOOCs for the curious armchair scholar, here is a list of offerings from provider edX, including one about SHARKS. All about sharks!

I have only just discovered edX, so (unlike Coursera, Future Learn and Open2Study) I have not done any of these courses, and don’t speak from experience. The format looks similar to Coursera, so you can pay to get a “verified certificate” for the course, or just choose to audit it (like a Scientologist… bad joke, sorry), which doesn’t cost anything. Like Coursera, edX has an app so you can work (on certain mobile-friendly courses) on your iPad or Android tablet.

Sharks! Global Biodiversity, Biology, and Conservation is from Cornell University and the University of Queensland, and looks like a complete primer about sharks, from their evolutionary and life history all the way through to management issues and human-shark interactions. The next sessions starts on 28 June. Will I see you there?

Tropical Coastal Ecosystems (also from the University of Queensland) is self-paced, which means you can start whenever you want to. The Great Barrier Reef is used as a study example in many instances, and the course deals with coral reefs, seagrass meadows, and mangrove swamps.

Two courses that are focused more specifically on climate and related science are:

Climate Change: The Science from the University of British Columbia in Canada doesn’t have any current or future sessions scheduled, but you can still view the course material. This course not only covers climate, science, but aims to equip you to evaluate climate science, and to communicate facts about the climate to others.

Sensing Planet Earth – Water and Ice from Chalmers University of Technology in Sweden deals with the measurement and monitoring of earth’s ice and water bodies, in order better to understand the changing climate.

Have fun!

Say yes to 22 new Marine Protected Areas for South Africa

Twenty two new marine protected areas have been proposed for South Africa. The benefits of MPAs are well known, so this is excellent news for the future of our marine environment. The public is invited to comment on the proposal, and as a responsible ocean loving individual, sending an email to comment would be one of the ways you can save the ocean. Read on to find out the details.

Proposed new MPAs for South Africa (existing ones in navy blue)
Proposed new MPAs for South Africa (existing ones in navy blue)

Included in the proposed new Marine Protected Areas are South Africa’s first offshore MPAs. The press release from the Department of Environmental Affairs states that:

Many of these new MPAs aim to protect offshore ecosystems and species, ranging from deep areas along the Namibian border to a more than tenfold expansion of iSimangaliso Wetland Park in the KwaZulu-Natal Province. They include charismatic features, such as, fossilised yellow wood forest at a depth of 120m off Port Nolloth, a deep cold-water coral reef standing 30m high off the seabed near Port Elizabeth and a world famous diving destination where seven shark species aggregate, at Protea Banks in KwaZulu-Natal. These MPAs also include undersea mountains, canyons, sandy plains, deep and shallow muds and diverse gravel habitats with unique fauna.

What good will these MPAs do? According to the press release:

The new MPAs will secure protection of marine habitats like reefs, mangroves and coastal wetlands which are required to help protect coastal communities from the results of storm surges, rising sea-levels and extreme weather. Offshore, these MPAs will protect vulnerable habitats and secure spawning grounds for various marine species, therefore helping to sustain fisheries and ensure long-term benefits important to food and job security.

The new MPAs will increase the protected portion of South Africa’s territorial waters from less than 0.5%, to 5%. The government has undertaken to get this figure to 10% by 2019.

What does this mean for you?

Scuba diving

If you’re a scuba diver, you probably know that diving in a Marine Protected Area – particularly in a no-take zone – is an extra special experience because of the abundant fish and other marine life. The prospect of richer, more diverse dive sites to explore is an exciting one, but there are more benefits to this proposal than just enhanced eco-tourism opportunities.

Scuba diving businesses will have to acquire permits from the Department of Environmental Affairs (for about R500 per year) to operate in the Marine Protected Areas. (This has been in force for some time, and ethical dive operators in Cape Town who take clients diving in any of the existing MPAs should be in possession of a permit already.) There are also the permits issued to individual scuba divers (for about R100 per year, obtainable at the post office) to dive in an MPA – you will see this mentioned in Tony’s newsletter now and then, as a reminder.

Environmental protection

Some of the new MPAs are in offshore regions that would otherwise be at risk from destructive trawl fishing and other exploitative activities such as mineral, oil and gas extraction from the seabed.

Many of these MPAs will, like the Tsitsikamma MPA, serve as nurseries for fish stocks. Recreational and commercial fisheries will benefit from allowing the fish to spawn unmolested in protected areas along the coast. Holding ourselves back from fishing everywhere, at every opportunity, shows long-term thinking, and will have short-term benefits as well as for future generations.

Undesirable activities

Not all of the MPAs will be closed to fishing – those of you familiar with the network of protected areas around the Cape Peninsula will be familiar with this idea. For example, a number of pelagic game- and baitfish species may be caught within the Controlled Pelagic Zones of the Amathole, iSimangaliso, Protea and Aliwal Shoal Marine Protected Areas. Commercial fishing permits may also be issued for use in the MPAs.

Existing discharges of effluent are permitted to continue – specifically into the Aliwal Shoal MPA.  This means that SAPPI may continue to pump wood-pulp effluent onto the dive sites there.

What to do?

If you would like to show your support for the proposal – and who doesn’t love a well-chosen MPA? – send an email to MPARegs@environment.gov.za. You have until 2 May 2016 to do so, and you can include any other relevant comments about the MPA proposal in your missive.

You can download the full document detailing the proposed new MPAs complete with maps, management regulations and co-ordinates (a 336 page pdf) here.

Tony and I are looking forward to passing over some of the new MPAs on the Agulhas Bank (maybe numbers 11 and 12 on the map above) next year – without getting wet. You can come too! (But you may have to impersonate a twitcher.)

Who to thank?

This project has been spearheaded by a team at SANBI (the South African National Biodiversity Institute) led by Dr Kerry Sink. Dr Sink has been awarded a prestigious Pew Fellowship in Marine Conservation for 2016, and her fellowship work encompasses a range of projects aimed at strengthening and expanding South Africa’s network of Marine Protected Areas.

We are extraordinarily fortunate to have a scientist and conservationist of Dr Sink’s calibre as a champion for MPAs in South Africa. So you can thank her!

Newsletter: Blooming tides

Hi divers

Weekend dive plans

Saturday: Launching at 6.00am from Simon’s Town jetty for a double tank dive

Coral display at the aquarium in Copenhagen
Coral display at the aquarium in Copenhagen

The water is really doing its best to limit diving right now. It is either murky green or way too windy for decent diving on a regular basis. At some point it will change, but I doubt it will change in time for the weekend. There are areas in False Bay that are clean and free of red tide, but you need to go and look for them.

Saturday has pretty strong south easterly wind and a fair amount of swell, Sunday is not looking much better. I have students who require shore and boat dives so I will launch at 6.00am on Saturday for a quick look and double tank dive, and plan the weekend around what we find.

If you’d like to be notified of diving plans that may materialise if we find suitable conditions, let me know!

regards

Tony Lindeque
076 817 1099
www.learntodivetoday.co.za
www.learntodivetoday.co.za/blog/

Diving is addictive!

To subscribe to receive this newsletter by email, use the form on this page!

Bookshelf: Sharks in Question

Sharks in Question – Victor G Springer & Joy P Gold

Sharks in Question
Sharks in Question

After an extremely enjoyable and informative experience with Whales and Dolphins in Question, another volume in the Smithsonian’s “in question” series, I sought out Sharks in Question.

Published in 1989, this book is chiefly enlightening as a primer in how shark science and attitudes towards sharks have progressed in the last quarter century. Like Ainley and Klimley’s Great White SharksSharks in Question is seriously dated. Far from making this a frustrating reading experience, I found it incredible how much more certain we are of so many things that the authors mention here in speculative terms.

If you’re looking for some current shark science, I would recommend Global Perspectives on the Biology and Life History of the White Shark or Sharks of the World. You could also check out the BBC’s wonderful Sharks series. If you are looking to complete your library of all things shark, however, you could find a place for this volume.

You might be able to get a copy here (South Africa), otherwise here or here.