Dredging for scallops

Scallops are one of many real delicacies to come from the sea but many people consider gathering them for themselves is just too hard to bother with. Instead they will settle for some bought from the local supermarket, where they will be clean, hassle free and if you’re lucky several days old.

While diving is an environmentally friendly option for gathering scallops it is beyond the means of many of us. I‘ve never dived and probably never will as I’m much happier sitting in a boat or on the shore breathing in air as nature intended, with nothing likely to sneak up behind me and bite me in half. An irrational fear for sure but that’s how it is. Needless to say I can’t teach you about diving for scallops but I certainly respect those who do and I leave those scallop beds alone. I do all of my dredging on the Manukau Harbour in areas where people don’t dive. Other west coast harbours have similar scallop beds so together with a little local knowledge the same techniques will apply.

The areas I target are generally around 4 to 5 metres deep at high tide, meaning that they are in very shallow water at low tide. That’s an important piece of advice right there because the easiest way to collect scallops is to stop at an exposed sand bar at low tide. If you choose a very big tide then harbours such as the Manukau and Kaipara will have large exposed mud flats at low tide.  It’s then a simple matter of wading the shallows and picking them up. It couldn’t be easier and it also shows you exactly where they are or alternatively, where they aren’t. Either way, you learn! You do need a keen eye to spot them but it is very easy to select the bigger ones. Of course you need to ensure that your boat is well anchored or you have a boat man onboard because if for any reason you can’t get back to your boat things will get very serious very quickly, especially as the tidal movement on the big tides will be severe.

I’ve heard many different theories about how you must drag against the tide and just as many that say you must go with the tide. My theory is that it doesn’t really matter! Recently after a bit of a fishing session with my youngest son Scott, we decided to dredge for scallops. I set us on a course, telling him to aim for something in the distance. At 16 he’s old enough to operate the boat and I went through the controls with him, giving him instructions not to touch the throttle and to let me know if any boats approached. As I busied myself setting the dredge, a process that took maybe a couple of minutes and not a word from Scott I looked up and saw we were heading back to where we came from. Having just completed a half circle there was nothing for it but to stop the boat and reset the drag. When it came in we had near our limit of 30 legal scallops.

That experience emphasises two important points: direction is not critical and you don’t need to tow the dredge for more than a few minutes – especially while you’re prospecting for them. Once the net is full you are simply disturbing the sea floor for no reason and several short drags will soon tell you if you are in the right spot.

The set up I use is just one of those budget models available from most of the bigger stores, I have 5 metres of 6mm chain attached to it and 20 metres of 10mm rope with the end tied to a stainless steel ring I had made up. Off that ring I have two ropes of around 3 metres long with a loop tied in the end of each one. I put each loop on the rear cleats of my boat. Alternatively you can just attach the rope directly to one cleat but that will cause the boat to slew to the side that the dredge is attached to. I don’t recommend that for small boats, especially if the sea is anything but calm. A ski pole makes the best attachment point but my bridle set up works just as well. Remember to attach the dredge to the cleat or pole before you do anything else, I’ve heard of many of them disappearing over the stern!

Before you set out make sure that the rope is coiled so it won’t tangle and there is nothing in the way that will prevent its smooth progress out the back end of your boat.

When I start to deploy the dredge I do so smoothly keeping tension on the rope at all times. That keeps it from tumbling or getting tangled up in the chain or rope. Once it is on the bottom, I feel for it ‘bumping’ along the sea floor which is similar to when you are drift fishing with a heavy sinker bouncing along a stony sea bed. If the rope goes tight and there is just a smooth heavy pull on the rope you will be scooping up mud and you don’t want that! You also don’t want to put the dredge out at speed, I get my boat chugging along just off idle and once the whole thing is out I increase speed to 3 knots which is around 1200rpm on my boat. A lot of people want to help you with this task but it really is best if you put the dredge out yourself. When you do, be careful not to wrap the rope around your hand. I’ve seen a few do that, luckily not when the dredge has struck heavy mud. If people are keen to help have one steer the ship and the others can keep a look out for other vessels.  Of course if there is a dive flag in the area, either come back later or find another scallop bed.

Although I said earlier that I don’t believe it makes a difference whether you drag with, against or across the current flow, retrieval is much easier if you drag against it. The boat tends to come to the dredge that way leaving the only muscle work required to lift it up to the boat. My boat has a duck board on the back which the dredge sits on nicely so no mess comes on board. Alternatively a good heavy tarp or towel draped over the gunnel will prevent scratching you shiny boat. A nylon tarp on the deck to place the dredge on keeps the mess to a minimum.

If you have a lot of empty shells or other debris with only one or two scallops, you are probably right on the edge of a bed so move 50m either side of where you did your first drag and try again before giving up on an area. A GPS is a fantastic aid to help build a picture of where the beds are clean and bountiful. Once you’re onto the tasty buggers, mark the spots so you cover an area rather than just a straight line from A to B.

Make yourself aware of the regulations for your area before you go and keep a couple of measures on board. You can easily make a measure yourself but there are some inexpensive multi species measures that do the job well. I make sure none pass through the gauge and if someone else is measuring I check the small looking ones they have already measured as a spot check. Counting your catch can be surprisingly tricky. I lay them out in pairs and arrange them into rows of ten scallops. It’s then a simple matter of counting the rows. That’s how fisheries officers count shellfish catches and it works for me too.

Sometimes you will find things other than scallops in your catch especially if you stray off into areas of sea grass or weed. On a couple of occasions where I’ve done this we’ve had sea horses in the dredge. It’s not uncommon to get starfish, crabs and little sucker fish. Unfortunately it isn’t uncommon to find beer cans and bottles, bait bags, berley nets and other rubbish. Take your crap home! I have heard of people scooping up fishing rods and long lost dredges too.

Strictly as research for this article of course, I was forced to go and harvest some scallops on the same week as I wrote this article. Three of us left the boat ramp at 5.00pm and we were back high and dry with our boat cleaned and a limit catch of 60 scallops an hour and a half later. That was even allowing for a photo session and a slow trip out in sloppy conditions. It took us two attempts with our first effort netting twenty six legal sized scallops. One more drag and we had sixty four if the things! That meant we had to throw 30 back. One answer I can’t give you is why you always get the big catches when you only need a few more. When that’s all we have to complain about though life’s pretty good isn’t it? Give it a go, it’s a rewarding way to spend an hour or so!