A South African Winter of Shark Research: The Adventure Continues

by Madeline Jehenself

The first project I worked on at the South African Shark Conservancy (SASC) was a portion of their broader Marine Ecology Research Programme (MERP) which explores the biodiversity of Walker Bay. Walker Bay is a gorgeous piece of the Atlantic Ocean between Hermanus to the northwest, and Gaansbaai, renowned white shark cage diving destination, to the southeast. These shallow, temperate waters are productive, however the extent of the biodiversity they contain (particularly when it comes to sharks!) is unknown.

Walker Bay as seen from an overlooking mountain & the idyllic town of Hermanus

To investigate, SASC uses basic rod and reel shore angling. They fish at 5 coastal habitats (estuary, sandy bottom, rocky shore, harbour, and kelp forest) all year long in order to compare catch rates of shark species, sexes, stages of maturity, and sizes between different habitat types, seasons, and years. Once a shark is caught a timer is immediately started, recording the length of time the fish is out of the water. The shark is laid on a measuring mat and measurements such as total length and precaudal length (distance from the tip of its rostrum to the base of its caudal fin on the dorsal side) are recorded. Sexual maturity (applicable only to males) is determined by checking the level of calcification, or stiffness, of their claspers. A fin clip of the first dorsal fin is taken for genetic analyses, and the shark is tagged before release. SASC uses spaghetti tags, which are the most basic identification tags out there for sharks. These tags are inserted directly adjacent to the first dorsal fin.

Spaghetti tags. These two would be used to tag smaller, bony fishes. The SASC tags are about 10cm long. Courtesy of the California Department of Fish and Wildlife, image modified.

Each tag has a unique ID number on it, which is recorded alongside the shark’s measurements. After release, changes in size and condition with subsequent recaptures are tracked. This information is used in studies of aging, growth, maturity, population dynamics, and site fidelity (its movements in relation to the place it was originally caught). Inserting a spaghetti tag is simple, but can be a bit stressful due to the stubbornly tough nature of a shark’s skin, which is covered in tooth-like dermal denticles!

A scanning electron micrograph of spiny dogfish (Squalus acanthias) denticles.


Since 2010, SASC has tagged 6 species of shark in Walker Bay: puffadder shyshark, dark shyshark, brown shyshark, leopard catshark, pyjama catshark, and one smoothhound shark. There has been an 18% recapture rate, and the sharks generally seem to favour kelp forests and rocky shores. These are just rough, preliminary findings, and the whole picture of shark biodiversity and habits will gain ecological sense as the Walker Bay sharks project continues!


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A South African Winter of Shark Research: The Adventure Begins


by Madeline Jehensef

When you are wholly invested in something, especially something that you have been building anticipation around for a long time, do you ever find yourself in a place of blissful ignorance where there is no possibility of a negative aspect existing about your something? Well, that was the place I was drawn from when I heard that there was a small group of protesters picketing outside the Maharani Hotel, the venue for Sharks International 2014.

The Elangeni-Maharani Hotel in Durban, SA. Note the blue and white Sharks International banners outside

At first, I felt guilty. I am a protester too, when there is a worthy cause! Was there something I was missing? My guilt subsided fairly quickly however, as I realized that these protesters were a tad uninformed. In my experience, I have found that there are two main types of ineffective peaceful protesting. The first (which does not describe the Sharks International protesters, by the way) are what I like to call ‘Umbrellavists’. These protesters have many issues they would like to bring to the table, but they tend not to distinguish between them at any given protest, regardless of the target audience. The second form is under-informed protesting, and this was the kind occurring at the conference. The Sharks 2014 protesters were picketing against the bather protection nets that are along some beaches of the east coast of South Africa to reduce interactions between beach-goers and large sharks. These are set by the KwaZulu-Natal (KZN) Sharks Board, the organization that played host for the conference.

The use of bather protection nets (a combination of drumlines and gill nets that are about 300m long, 6m deep, with 51cm stretched mesh) is controversial in many countries that employ them because they are indiscriminate in their catch; as you can see in the table below, animals like sea turtles, dolphins, and seabirds are also caught in these nets.

Table retrieved from the KZN Sharks Board website: http://www.shark.co.za/CatchStatistics Note: ‘C’ stands for total catch, ‘R’ stands for released individuals

This bycatch is clearly not ideal however, it is important to note that the KZN Sharks Board is also a very active research body and uses the specimens it finds for daily dissections and studies. Along with conducting their own studies on shark biology and behaviour, they have research collaborations with many organizations locally and internationally, they provide samples to researchers around the world, and they participate in scientific conversation by attending and hosting events like Sharks International 2014. What’s more, they are actively pursuing non-lethal shark deterrents and have reduced the use of bather protection nets to half their original extent along the east coast. If this background information didn’t convince the protesters, they were free to peruse the conference program which was (and still is!) available to the public on the website.

I feel that the real issue here is that humans have an irrational fear of entering the sea and we should instead acknowledge and rejoice that there are still parts of our world that are ‘wilderness’! The good news is that this paradigm shift is underway with the facilitation of science and passionate people. Following the conference, I was lucky enough to spend two months with some of the most passionate scientists I’ve ever met, at the most beautiful little research station I’ve ever seen.


The South African Shark Conservancy in the heart Hermanus, Western Cape. Photo courtesy or Tamzyn Zweig

The South African Shark Conservancy (SASC) is literally surrounded by oceanic inspiration while being steps away from the little bustling tourist town of Hermanus, what a glorious place to work! On my first morning, as I was led down the windy stone stairs and along a narrow outcrop of rock with the waves lapping the smooth fluid stone just feet below me, I started to think that we must be on a scenic detour before heading to SASC because there was no way a building could fit here. The next two months were a dream as I worked on some of the 13 on-going research projects, interacted with the public, and spent time with the gorgeous creatures of this biodiverse coastline that was so unfamiliar to me. Southern Africa is home to 34 endemic sharks, which means these species are found nowhere else in the world…to put that into perspective, Canada is only home to 28 species of shark in total! In my next entry I’ll tell you a bit more about these South African sharks, including the stripey pyjama catshark shown below, and what SASC is doing to protect them.


South African endemic pyjama catshark (Poroderma africanum) spotted on a dive off the Simon’s Town coast

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A South African Winter of Shark Research

by Madeline Jehenself 

As a freshly minted marine biology graduate from Canada with a particular fascination for sharks, you can imagine my overwhelming excitement to launch straight into three months in South Africa, one of the shark research capitals of the world! My name is Madeline Jehnself, and the following blog series will focus on the captivating and important field of marine conservation through the lens of my experiences in Mama Africa this past summer. First, I’ll take you to the scientific conference I attended in Durban, then I’ll tell you a bit about each research project I was involved in while I was studying sharks and marine ecology as an intern at the South African Shark Conservancy.

Despite booking my flights 5 months in advance, I must say that this adventure didn’t fully enter into my reality until I was holding a brandy and coke at the suave Maharani Hotel overlooking the Indian Ocean in Durban. Just over a month before I was hopped up on soy lattes, haphazardly pouring over research papers and government reports as I (somewhat desperately) tried to figure out what significance my honours research could possibly hold in the world of marine science, and perpetually freaking out about every detail of my thesis. Is ostracoda a genus name? Should I capitalize it? Italicize? What reference style guide should I use? Is CSE too simple? APA too complicated? WILL I PASS UNIVERSITY?!

Map of South Africa, with Durban circled in red

Now, don’t be fooled – schmoozing at an elegant hotel in a city reminiscent of Miami Beach was only the setting of 1 of my 13 weeks in South Africa…my life hadn’t quite taken THAT dramatic of a turn. I was at the gorgeous Maharani Hotel during the first week of June while attending the Sharks International Conference. The meeting brought together academic, governmental, and non-governmental researchers from around the world to discuss the successes, challenges, and future priorities for the study and conservation of chondrichthyes (the class of fishes comprised of sharks, skates, rays, and chimaeras). In other words, it was the prime environment to completely nerd-out about the coolest and most imperilled creatures on our planet. Sharks are very different from most of their bony fish relatives, these ancient creatures have evolved to live a long time, grow slowly, and have few offspring with long gestation periods (we refer to the combination of these traits as a ‘slow life history’). Slow life histories are part of the reason sharks have thrived in the oceans for over 420 million years, but they are also the reason sharks are extremely slow to recover from overfishing and environmental impacts.

The Great Ilanga Room at the Southern Sun Elangeni and Maharani Hotel was the larger of two rooms used for talks during Sharks International 2014.


The daily itinerary at Sharks International involved listening to a series of 15 minute talks about chondrichthyes from 8:30am – 4:30pm.and the evenings were no less shark-y! Some of the nightly gatherings included ‘Welcome Drinks’ with traditional Zulu dancers, a gala hosted by the Save Our Seas Foundation, a science communication and social media workshop by David Shiffman (Ph.D. student from the University of Miami), and a dorsal fin identification workshop by Dr. Demian Chapman (which is usually held for customs officers to help them enforce international fin trade laws). As my first international                                               conference, I was relieved to find that the week wasn’t                                                       all talk. I learned practical skills and I heard some incredible stories.

Interestingly, the most valuable lesson I learned from Sharks International was that there is no doubt in my mind about devoting my life to conserving and rebuilding the ocean. In my next entry I’ll discuss an unanticipated point of conflict at Sharks International before introducing my newly found home-away-from-home, the South African Shark Conservancy!

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Skates and Rays in Atlantic Canada

by Hilary Goodwin

Skates and rays are often referred to as “flat sharks”. They are the lesser known chondrichthyans, a class of fish that includes sharks, sawfish, and chimaeras. Skates and rays are part of the batoid superorder, which is composed of 574 species. That’s more species than all nine orders of sharks combined! Batoids are cartilaginous fish like sharks, but tend to inhabit soft benthic environments. In Canada, batoids range from the Northern Labrador Sea down to the Bay of Fundy and Georges Bank and can be found in a wide range of depths up to 4,000 m.

You may be surprised to learn there are 14 skate and 4 ray species in Atlantic Canada – for more details on the diversity of skates and rays, please visit the WWF Identification Guide to Sharks, Skates, Rays and Chimaeras of Atlantic Canada – http://awsassets.wwf.ca/downloads/identification_guide_to_sharks__skates__rays_and_chimaeras_of_atlantic_canada.pdf.

There are two main differences between skates and rays – where they live and how they reproduce. Skates are present at higher latitudes and in deeper waters while rays prefer shallower and warmer temperate to tropical waters. To reproduce, skates produce egg cases (oviparous) while rays produce live young (viviparous).

The Bedford Institute of Oceanography and the Department of Fisheries and Oceans (DFO) have undertaken studies on skate ageing, reproduction characteristics, and population trajectories. Without these types of studies, it is difficult to adequately manage skate populations in Atlantic Canadian waters. As skates are both targeted and caught as bycatch, they have been the more studied batoid.
Some scientists have argued that skates (Family Rajidae) are the most vulnerable of exploited marine fishes. Between 2005 and 2012, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has assessed four species of skate, including their sub-populations – Winter skate (four sub-populations), Barndoor skate, Smooth skate (four sub-populations), and Thorny skate.

Summary of COSEWIC assessments for Atlantic skate species

Scientists estimate that Winter, Thorny, and Smooth skate populations have declined as much as 90 percent off the Eastern Scotian Shelf since 1970. Even though a sub-population species of Winter and Smooth skate have been assessed as endangered and threatened, no skate species have been listed under the Species at Risk Act (SARA). The consideration to list Winter skate under SARA in 2008 failed, and recovery targets for Winter skate have not been set.

Winter skate

Atlantic Torpedo Ray © Sue Scott









For more information on skate fisheries, discards, and management, please tune into next month’s blog on skate management in Atlantic Canada.


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This year at NAFO…

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by Hilary Goodwin Last week, the Northwest Atlantic Fisheries Organization (NAFO) met in Halifax, Nova Scotia for their annual meeting. NAFO, an intergovernmental fisheries science and management body, is the only Regional Fishery Management Organization (RFMO) to have an elasmobranch … Continue reading

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