There is something about diving arches that really gets my blood going. In one short dive you could easily see more life in one tiny area than if you combined a dozen dives in other locations! Recently I watched an episode of Robson Green’s Extreme Fishing show. He was about to jump in and have a spearfish. The backdrop showed a group of islands, one of which had an arch running through the middle of it. Without any knowledge of the area, my immediate thought was that, if that were me, I’d visit the arch first, as it looked the most likely place to get a feed. And, sure enough, the arch was where he went and got some nice fish.

If you’re a fisherman, there’s a lot to be said about getting in the water to see for yourself where and why fish like to hang out in certain places. It will also provide the different species you’re likely to encounter at the differing phases of the tide. All this information will give you more confidence to fish different spots, and if you put what you have observed and learnt into practice, your fishing success will no doubt increase, too. But what is it that makes arches such a hot spot?

Well, most of the ocean is like a desert, but wherever you find food, you will find life, and I know it’s hardly profound, but wherever you find lots of food, you’ll probably find lots of animals that want to eat it! Most of us know that sudden rises on the ocean floor are great places to fish. That’s where the planktonic fodder the whole food chain relies on is concentrated as the current pushes up and over the rise. There you will find fish that feed on the plankton (baitfish), along with the rest of the food chain, including the larger predators prowling the outskirts. I guess fish are not too dissimilar to us in that they know where to find an easy feed, and they will go for an easy feed over a hard one anytime!

Arches are very similar to pins in that the food suddenly gets concentrated, this time through a narrow gap. It’s likely you’ll find the baitfish facing into the current at the end where the current is hitting first, as this is where the food concentration is at it’s greatest. In northern regions the most common fish you’ll see here are demoiselles, blue maomao and sweep, with trevally normally not too far away. Due to this overabundance of life, you can guarantee that the predators are nearby as well, with kingies often seen prowling just on the outer edge or occasionally cruising menacingly through the arch.

Other predators such as snapper and sharks could well be present too, but because of their shy nature and the noise that our bubbles make, they are not commonly seen – unless diving in a marine reserve where snapper become tame! But the big appeal for me at these spots is that you’re never too sure what you’ll see. Sometimes it can be as busy as peak hour on a motorway in Auckland, and at others it’s like a back-country road at 3am in the morning.

Last week I was invited to do some filming with Outer Gulf Charters at a Great Barrier Island rock I’d visited plenty of times before. It starts at 5m below the surface and goes straight down to about 30m below. At 18m there’s an archway that can be spectacular for fish, and frequently I’ve found kingfish sitting just under the roof, swimming slowly into the current to keep their position. Occasionally a large snapper will accompany them, along with the ever-present schools of large porae and colourful mado. It’s different from the previous arches I’ve mentioned though, as it’s the predators that seem to be resting up, rather than the baitfish, which are right out to the front of the rock. I wonder if it’s a cleaning station, where large fish come to get the parasites cleaned off their scales?

I’m going to have a closer look next time, as these cleaner stations are real handy, being like truck stops where every large fish in the area knows it can come regularly for a good clean-up and service! Something that definitely makes this a hotspot is that there’s deeper water nearby and it has a nice current running past – fish love this scenario, as they have easy access from the deep and there is always plenty of bait out the front for a meal.

On this particular day the visibility was not great, so despite being buzzed by a good school of kingies a couple of times, and seeing a school of golden snapper and mado just below us in the green haze, I decided to fix my attention on the walls and see what I could film up close. I’d heard that the walls are spectacular here, and what I found definitely did not disappoint. Under my bright LED lights they came alive with an array of vivid colours and shapes. Colonies of bright purple, pink and orange jewel anemones were everywhere, with bright yellow finger sponges scattered down the wall – not a centimetre was uncovered…

But something I’ve never seen before was an army of Jason’s nudibranchs spread up the cliff face. I’ve got to say I haven’t spent much time trying to find nudibranchs, but today you would have had to be blind not to see them, possessing stunning purple bodies and what looked like white dreadlocks on top swaying in the current. Some were large too – up to about 100mm. Normally I prefer filming fish, especially in such a spectacular setting, but with the rather average vis forcing me to turn my attention to something I wouldn’t normally look at, an ordinary dive was turned into something very different and quite spectacular.

Tomorrow I’m heading out to dive at New Zealand’s capital for stunning arches – the Poor Knights Islands. There’s no shortage of them there, and it’s one place I can’t get enough of!

Have a great time over summer. Dive safely with a buddy and fly your dive flag always. But even with a flag up, take real care, as there are some cowboys on the water who don’t know what one is!