Year in the Wild Blog

Days 69-70 – YITW 2013-14 – De Hoop’s fish study helping to save SA’s marine life

Most visitors to De Hoop are bowled over by the superb scenery.

Located just to the east of the southern-most tip of Africa, this CapeNature protected area comprises both terrestrial and marine habitats. It’s extremely photogenic, with blinding-white sanddunes, turquoise-emerald water, secluded coves, wild beaches, and flowering fynbos. Then there’s the De Hoop Vlei, one of the best places in South Africa for birding, and the Potberg Mountains, which shelter one of the last breeding colonies of Cape griffon vultures in the country.

The manor house at De Hoop, part of the fantastic collection of accommodation at the reserve. The beautiful De Hoop vlei is one of the main features of this protected area.

The gravel road that leads through De Hoop to the coast

Looking east from Koppie Alleen on the De Hoop coast.

The accommodation at De Hoop Collection is also among the best of any protected area – more on this in another blog.

But De Hoop is ultra special because of it’s Marine Protected Area, which extends 46km along the coast, and three nautical miles out to sea. Much of De Hoop’s magic resides in this oceanic habitat. The most obvious evidence of this are the southern-right whales, which come in their hundreds during the Southern Hemisphere spring to calve and mate in the bay, making this reserve one of the best places in the world to see whales from the shore, and probably the world’s most important nursery for this species. (The Whale Trail in the reserve is one of the premier hiking routes in the country, and offers plenty of opportunities to see the whales).

Southern-right whale and her calf in De Hoop's MPA

But, equally important, the MPA is also the site of one of the longest-running and most comprehensive fish studies in the world, the evidence of which has had huge implications for marine conservation in South Africa and internationally.

The researcher at the centre of this study is Colin Attwood, an associate professor of Zoology at University of Cape Town. While I was at De Hoop, Colin was there along with several other anglers, as part of the fish-tagging study that has been running since 1987.

Every year in October, Colin and his team of anglers use standardised angling techniques to catch fish in designated areas. All caught fish are recorded, identified, measured and then released. Some of them are tagged, so if these fish are caught again, their movements can be monitored. Around 50 000 fish to date have been caught and released at De Hoop, and of these, about 30 000 have been tagged.

About 300 species of fish can be found in De Hoop’s marine area, but Colin and his monitoring team typically catch and release about 40 of these, including dusky kob, galjoen, white musselcracker, black musselcracker, red roman, elf, and red and white steenbras. Also caught and released are spotted gully shark, smooth hound shark, lesser guitar fish, eagle ray, blacktail, zebra and bronze bream.

Colin Attwood and one of his beloved galjoen, before tagging it and releasing back into the ocean.

Colin Attwood tagging a galjoen, before releasing it back into the ocean at De Hoop.

I have chatted to Colin a few times in the past, and the results and implications of the study are fascinating.

“De Hoop was a watershed for marine protected areas,” Colin explained. “It was regarded as one of the prime angling areas in the country up until it’s proclamation as an MPA in 1985. Then fishermen were excluded and it presented an excellent opportunity to monitor what will happen to species like galjoen, if they are protected.”

“The main result of the study is that the fish showed a massive recovery. That’s not surprising today. We know now that if we create marine reserves fish stocks will recover. But in 1985, that was big news, because marine reserves were very controversial at the time. No one really believed that MPAs would make any difference. Most people thought that line anglers had no impact. Instead, everyone blamed trawlers. Fishermen and scientists thought that fish moved around so much that it wouldn’t help closing a particular area.”

“This all proved to be false of course. Many fish species are resident, and are very reluctant to move. The marine reserve definitely helped with the recovery of fish.”

Red Roman fish on a reef at De Hoop

A ragged-tooth shark surrounded by sardines at De Hoop

“The big insight came with the tagging which proved that the fish weren’t moving all over the show. No-one at the time would have believed that a galjoen spends its whole life in an area of three to 400 metres. They are known to move, but the incidence of movement is less than 5% of its life. If you tally up all the time that it spends away from its area, its around 5%. And we know they always come back again.”

But how do marine protected areas benefit fishermen in areas that aren’t protected? If fish species like galjoen, red roman and musselcracker don’t move much, then is the rest of the coastline doomed to being overfished and devoid of life? This is where the implications of MPAs are massive for not only marine conservation but also the nation’s food security.

“Most of the benefit is the result of the spread of eggs and larvae,” Colin said. “A fish can lay two to five hundred thousand eggs in a season, and those eggs float for a short time, then they hatch into larvae which can’t swim very well, so they are at the mercy of currents, which distribute the eggs and larvae all over the ocean.”

“In other words, De Hoop is home to a centralized breeding stock which can re-populate a much larger area. The analogy is like having money in the bank. If you have a certain amount of capital, then you can live off the interest. It’s not a perfect analogy, but sometimes it gets through to fisherman that you can’t take everything out of the sea all at once. You have to leave a core amount of fish to breed. And the MPA concept works because of the spreading of eggs and larvae, rather than spreading of adult fish.”

An octopus on a reef, with red roman nearby

The bizarre and wonderful compass jellyfish

A few species of fish will move further than their eggs, like elf and white steenbras which are migratory, sometimes moving a thousand kilometres. But many fish will spend their whole lives within a certain area. And some fish – like red roman – have the remarkable ability to change sex as they get older. The small, young fish are females, and once they grow to a certain size, they turn into males. So if all the big (male) fish are removed it creates a huge imbalance in the breeding ratio, and the species could die out as a result.

“Fishing changes the numbers drastically,” Colin emphasised. “If there are 300 species in an area, fishing might affect 30 of them. Fishing disrupts the balance and this filters all the way down to the tiny benthic invertebrates at the bottom of the food chain.”

It’s like reducing the number of lions in Kruger National Park, or reducing the elephant numbers dramatically. If you reduce the numbers of large animals like these, it has a top-down effect on the ecology, and the entire habitat of an area is disrupted because of the reduction of a key species. The same thing happens in the ocean.”

The De Hoop fish study has had big ramifications for ocean conservation around the world. The results of the study were published internationally and since then other studies around the world have proven the same thing: if you create a marine reserve in an area that is heavily fished, the fish will come back, and they will repopulate other areas with their eggs and larvae.

“It seems incredibly logical now in hindsight,” Colin said. “But even some of the best thinkers at the time were convinced the MPA wouldn’t make a difference. Today it’s common knowledge fortunately.”

And although De Hoop wasn’t the first MPA in South Africa (Tsitsikamma is the oldest, proclaimed in 1964), the fish-tagging research study at De Hoop was the first of its kind.

Two anglers on Colin Attwood's research team

If it wasn’t for the South African military’s missile testing range that is located to the west of De Hoop, a reserve and MPA may never have been declared. The government didn’t want large communities of people living in what is today De Hoop Nature Reserve, and they didn’t want fishermen on boats offshore, in case a wayward missile came crashing down. Testing does still occur, but only for a few days every year.

“The muscle for the protection of De Hoop’s oceans didn’t come from conservation. It came from the military exclusion zones, so without the military the reserve wouldn’t have been proclaimed. The environmental arguments at the time for the proclamation of a protected area weren’t strong enough to win the day.”

It’s not often that we can thank the military for it’s contribution to conservation, but in De Hoop’s case, there was a valuable co-incidence, because the coastline here proved to be a perfect area for a fish study.

“The De Hoop coastline is not unique,” Colin emphasised. “That’s the interesting thing about it, and that’s why its so good to study, because it’s representative of so much of the rest of the southern Cape coast. If in the year 1700 someone said there is a horrible civilization coming, and we should proclaim reserves now, I would not have proclaimed one at De Hoop. There would have been nothing at De Hoop that would have made me say ‘Goodness this is special.'”

“In fact, De Hoop’s coastline is very ‘ordinary’ compared to other areas of SA’s coast. There are no quiet bays, and there is comparatively little production of fish, unlike False Bay for instance, which is highly productive because it’s shallow, big, and protected from waves, attracing a wide variety of juvenile fish. De Hoop can’t compare really to places like Langebaan lagoon, Algoa Bay, Saldanha Bay or Mossel Bay, all of which are are nodes of production for fish stocks.”

“De Hoop is quite the opposite. It’s very exposed, there’s little protection for juvenile fish, and it’s habitat is repeated all along the coast. You’ll find the same broken sandstone shoreline at Tsistikamma, Port Elizabeth, Struisbaai, Goukamma, and all along the southern Cape coast. So there is nothing particularly special or unique, but this is why it makes such a good place to study the recovery of fish.”

De Hoop’s marine protected area may be one of the best examples of what can be achieved through conservation. Take a seemingly ordinary area that has been exploited to dangerous levels, then protect it, and see what happens. The spectacular recovery of fish is now scientifically proven.

Just 1% of the world’s oceans are formally protected. Let’s hope that more MPAs are declared – our ethics, and survival, demands it.

**Many thanks to award-winning photographers Jean Tresfon and Peter Chadwick (a former reserve manager at De Hoop), who joined me for a few days at De Hoop. And thanks to Jean for the use of his spectacular underwater images from De Hoop. Jean is a seasoned international diver and has dived at De Hoop several times. He believes the marine life compares with the best anywhere in the world. Not bad for an “ordinary” piece of coastline!**

For more, go to www.yearinthewild.com and www.facebook.com/yearinthewild. Check out my Flickr photos at www.flickr.com/scottnramsay and my Instagram photos at www.instagram.com/wildscotty. Twitter on www.twitter.com/yearinthewild.

Thanks to my partners Cape Union MartFord EverestGoodyear, and K-Way.

As well as WildCardEeziAwnFrontrunnerGlobecommHetznerNational LunaOutdoor PhotoSafari Centre Cape Town, Tracks 4 Africa, and Vodacom.

Conservation partners BirdLife South AfricaBotswana Department of Wildlife and National ParksCapeNatureEastern Cape Parks and TourismEzemvelo KZN WildlifeGorongosa National ParkiSimangaliso Wetland Park, Namibia Wildlife Resorts, Parque Nacional do Limpopo, South African National Parks and Zimbabwe Parks and Wildlife Management Authority.

3 comments

  • Very glad to see the rejuvenation of the marine live in the area. I have been going to De Hoop for the last 30 odd years and was dismayed the first time I found out that the marine life along the coast was so dangerously in need of protection. It is one of the few success stories from around the world. Keep up the good work. Thank you for caring

    • Thanks Eric. I’ve travelled now enough around SA’s coastal areas to see for myself the difference between protected areas and exploited areas. It amazes me that skeptics still doubt the value of protecting our natural heritage – including marine areas. I’m currently in Agulhas National Park, and the ocean offshore of this park is not protected in any way. The shoreline and birdlife just can’t compare to that at De Hoop or Goukamma. I don’t need to be a scientist, and I don’t need to be a researcher to tell you that protection makes an unbelievable difference…I walked several kilomeres of beach at both De Hoop and Agulhas, and the difference is startling, even though the habitat is largely similar. For example, the Black Oystercatcher birds. At De Hoop, I stopped counting them – there are new pairs every hundred metres. At Agulhas, I counted just a few pairs over an equivalent distance of beach. This also applies to other species, and I’m sure this applies to the ocean reefs and fish life…

  • I have always been intrigued with your exploration adventures, have a lot of respect for your insight and knowledge, and find your photographs very inspirational. I was wondering what your take(feeling) is with regard the new hotel within the DE HOOP nature reserve. And in particular its impact on the marine life once it is operational. I have attempted to obtain documentation and environmental studies for this development, and to date, have not had any feed back from the National Authorities, Cape Nature, and or Denel. Africa can be protected one-step-at-a-time, it can also be lost one-step-at-a-time. Thank you for making the difference.

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