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Fish Conditioning: Do fish become conditioned by contact with divers?

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In Mauritius, some of the species are completely relaxed, and others extremely nervous around divers. The most remarkable are the sharks in the shark pit in Mauritius. We have been there with a small group to find as many as 23 sharks finning around in the washing machine current. To them we do not exist. They completely ignore us.

Once they have got used to the fact that the air-breathers are harmless they go about their business happily, unafraid of the invaders.

In Mozambique the Potato Bass are happy to interact with divers, lying on the sand, eyeing them hopefully, swimming beside them and rubbing against them. The legendary Bert was among these.

The controversy over Cage Diving and chumming for sharks rages on, and although we enjoy the adrenalin rush of the Tiger Shark Dive at Aliwal Shoal, there is always a nagging doubt that we are supporting something that could lead to later danger. It is extremely rare for a diver to be attacked by a shark, unless he is in a bait ball or in the wrong place, or behaves foolishly. The Dive Operators who offer these extreme experiences have never themselves felt in any danger.

The raggies at Aliwal shoal are like bull terriers. They are completely familiar with divers, and they are unfazed by photographers. The pregnant females at Sodwana fin trance-like around groups of divers.

I watched Walter Bernardis brush a piece of sardine away from my buddy’s head just as a Black Tip was diving for it, and the Black Tip veered away from his hand. Shark diving is exhilarating, but I have never felt threatened by the animals themselves. After five years of diving with the Tigers, I have noticed that the grey reef and black tips that come to feed are no longer wary of divers. They brush you out of the way to reach the bait ball. Once they lose their fear of divers, these sharks are completely relaxed in the water.

The one animal that always seems completely aloof, has never changed, and which completely ignores diver and which typifies the apex predator is the Tiger. Nothing changes their behaviour that I have ever seen. They are always looking for something to taste. They are always alert to anything new in their world. They will always nibble on anything unfamiliar, and a nibble from a tiger can remove most of your torso.

Is it a bad thing for fishes to become conditioned to the presence of divers in their private domain? Theoretically, anything that changes the behaviour of a creature in its natural habitat is unwarrantable interference. However, the test of stress in a creature is whether it continues to live, to eat and to breed and the evidence of stress-free fish life is everywhere.

In the bad old days, Dive Masters in Mauritius used to conceal pieces of uneaten cheap Government bread in their BC pockets. Unnoticed by the early naiive Resort Course divers, the DMs crumble the bread into the water around them, and are soon mobbed by shoals of damsels, who like nothing more than a little French loaf for breakfast.

When you dived with certain Dive Operators there you had to swat away the aggressively seeking damsels. They bit your hands or the naked areas on your face. Their teeth are too small to draw blood, but the nip was painful nonetheless. Conditioned to expect something from divers? Absolutely.

At Sodwana Bay on Stringer Reef and on Quarter Mile Reef the Sergeant Majors (Abdadufduf abdadufduf ) lay their eggs in nests in the hollows of the eroded rocks and caverns. In December they can be seen hovering anxiously over their nests, but if a diver gets too close they dart away, and the wily wrasses pile in and gobble their eggs.

Incredibly, the Wrasses know they fear divers, and we have often been plagued by colourful wrasses weaving seductively in front of the camera lens, and then darting towards the Sergeant Majors’ nests hoping we will follow them. It’s almost as though they are saying, “Come on guys, come and look at these eggs, come and photograph these fish.” We have often seen pairs of mournful-looking Sergeant Majors rushing back to their eggless nests after an oblivious dive group has finned down for a closer look.

Conditioning? Looks like it.

Less obvious conditioning is on new or undiscovered reefs, where the fish are much more nervous when a group of divers arrives, and whole shoals will fin away from the intruders. I’ve seen this happen at little –known Reefs like Fusilier, or Snapper College at Sodwana.

Perhaps, just as we are learning about Reef Fish, they are learning about us – and if their behaviour is anything to go by, once they get to know us, they simply accept us.


Words Jill Holloway

Pic David Holloway

Copyright Ocean Spirit

www.osdiving.com

Jill Holloway lives in Mauritius and at Sodwana Bay Isimangaliso Wetland Park in South Africa. A PADI qualified Nitrox diver with over 1,500 dives, she is a passionate observer and preserver of the marine environment, and has a database of over 35,000 fish pics and hundreds of Gopro videos on fish behaviour, which she shares with her readers.

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Scubapro Free Octopus Promotion 2024

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scubapro

Free Octopus with every purchase of a SCUBAPRO regulator system

Just in time for the spring season, divers can save money with the FREE OCTOPUS SPRING PROMOTION! Until July 31st SCUBAPRO offers an Octopus for free
with every purchase of a regulator system!

Get a free S270 OCTOPUS with purchase of these combinations:

MK25 EVO or MK19 EVO with A700

MK25 EVO or MK19 EVO with S620Ti

MK25 EVO or MK19 EVO with D420

MK25 EVO Din mit S620Ti-X

Get a free R105 OCTOPUS with purchase of the following combinations:

MK25 EVO or MK19 EVO with G260

MK25 EVO or MK17 EVO with S600

SCUBAPRO offers a 30-year first owner warranty on all regulators, with a revision period of two years or 100 dives. All SCUBAPRO regulators are of course certified according to the new European test standard EN250-2014.

Available at participating SCUBAPRO dealers. Promotion may not be available in all regions. Find an authorized SCUBAPRO Dealer at scubapro.com.

More information available on www.scubapro.com.

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Northern Red Sea Reefs and Wrecks Trip Report, Part 3: The Mighty Thistlegorm

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red sea

Jake Davies boards Ghazala Explorer for an unforgettable Red Sea diving experience…

Overnight, the wind picked up, making the planned morning dive a bit bumpy on the Zodiacs to the drop point on Thomas Reef. There, we would dive along the reef before descending through the canyon and then passing under the arch before ascending the wall with a gentle drift. The site provided great encounters with more pelagic species, including shoals of large barracuda, tuna, and bigeye trevally.

Once back on the boat, it was time to get everything tied down again as we would head back south. This time, with the wind behind us, heading to Ras Mohammed to dive Jackfish Alley for another great gentle drift wall dive before then heading up the coast towards the Gulf of Suez to moor up at the wreck of the Thistlegorm. This being the highlight wreck dive of the trip and for many onboard, including myself, it was the first time diving this iconic wreck. I had heard so much about the wreck from friends, and globally, this is a must on any diver’s list. Fortunately for us, there was only one other boat at the site, which was a rarity. A great briefing was delivered by Ahmed, who provided a detailed background about the wreck’s history along with all the required safety information as the currents and visibility at the site can be variable.

red sea

Kitting up, there was a lot of excitement on deck before entering the water and heading down the shoreline. Descending to the wreck, there was a light northerly current which reduced the visibility, making it feel more like the conditions that can be found off the Welsh coast. At 10m from the bottom, the outline of the wreck appeared as we reached the area of the wreck which had been bombed, as our mooring line was attached to part of the propeller shaft. Arriving on deck, instantly everywhere you looked there were many of the supplies which the ship was carrying, including Bren Carrier tanks and projectiles that instantly stood out.

red sea

We headed around the exterior, taking a look at the large propeller and guns mounted on deck before entering the wreck on the port side to take a look in the holds. It was incredible to see all the trucks, Norton 16H, and BSA motorcycles still perfectly stacked within, providing a real snapshot in time.

red sea

Overall, we had four dives on the Thistlegorm, where for all of the dives we were the only group in the water, and at times, there were just three of us on the whole wreck, which made it even more special, especially knowing that most days the wreck has hundreds of divers. Along with the history of the wreck, there was plenty of marine life on the wreck and around, from big green turtles to batfish, along with shoals of mackerel being hunted by trevally. Some unforgettable dives.

red sea

The final leg of the trip saw us cross back over the Suez Canal to the Gobal Islands where we planned to stay the night and do three dives at the Dolphin House for the potential of sharing the dive with dolphins. The site, which included a channel that was teeming with reef fish, especially large numbers of goatfish that swam in large shoals along the edge of the reef. These were nice relaxing dives to end the week. Unfortunately, the dolphins didn’t show up, which was okay as like all marine life they are difficult to predict and you can’t guarantee what’s going to be seen. With the last dive complete, we headed back to port for the final night where it was time to clean all the kit and pack before the departure flight the next day.

red sea

The whole week from start to finish on Ghazala Explorer was amazing; the boat had all the facilities you need for a comfortable week aboard. The crew were always there to help throughout the day and the chefs providing top quality food which was required after every dive. The itinerary providing some of the best diving with a nice mixture of wreck and reef dives. I would recommend the trip to anyone, whether it’s your first Red Sea liveaboard in the Red Sea or you’re revisiting. Hopefully, it’s not too long before I head back to explore more of the Red Sea onboard Ghazala Explorer.

red sea

To find out more about the Northern Red Sea reef and wrecks itineraries aboard Ghazala Explorer, or to book, contact Scuba Travel now:

Email: dive@scubatravel.com

Tel: +44 (0)1483 411590

www.scubatravel.com

Photos: Jake Davies / Avalon.Red

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