Winter still has its grip on the watery world at this time of year, however Matt Lind shares how to pick the hot conditions for cold water diving and hunting.
Cool gear to handle the cold
Winter diving can be very successful but there are a couple of key considerations. The first is simply dealing with the colder water. You can’t concentrate or dive well when you’re cold, so you must keep warm.
Using the right wetsuit means cold water simply isn’t a problem. For me that’s a full 7mm suit but I dive with other guys that are able to get away with a 5mm and others that need a 9mm.
Wind chill out of the water is another major factor especially diving out of small boats. Smoothskin wetsuits have a chicle rubber exterior rather than the usual nylon so they cut the wind and dry instantly.
I have a set of commercial fishing wet-weathers that I always wear over the top of my suit whenever I’m travelling any distance in an open boat and that includes the gumboots. I get stick from my friends but it makes a huge difference to me staying warm over a long day.
Carefully choosing in cold conditons
The next key is choosing the right conditions. Bad visibility and surgey conditions make diving especially hard.
Learning the right weather conditions for your dive sites makes all the difference when it comes to cold water diving. The easiest part to picking the conditions is judging wind and swell conditions.
For snapper snooping especially we need to have perfectly calm conditions so the snapper come and park up in the shallows.
Everyone has their favourite weather website, but I personally just look at the Metservice site as they tend to be pretty conservative.
For shore diving any on-shore swell over say half a meter is going to affect you. If the swell is over a meter it will wrap around points so you might be better off holding out for a calmer day.
Off-shore winds of virtually any strength are good. On-shore winds are not. Anything approaching about 10 knots is going to start being a pain. On-shore winds over 10 knots are a write-off.
Visibility conditions can be much harder to pick. Underwater visibility is affected by three main factors: algae, swell and rain run-off.
One of the best things about winter and early spring diving is that once the water drops below about 18 degrees the algal blooms that can destroy visibility through summer are all but eliminated. Any swell will stir up the bottom and affect visibility.
The amount of swell needed to muck things up varies a lot depending on bottom composition so a bit of local knowledge is necessary here. The good news about bad vis caused by swell is that as soon as the swell dies off, all the sand and other particles making the water murky will drop and the conditions will clear within a day or two.
The worst thing for visibility is run-off. This is what causes the muddy, brown vis that divers hate so much. How long it takes to clear after the rain stops is dependent on a lot of factors, the main one being how heavy the rain was.
It can take days for swollen rivers to go down as the rain makes its way from the catchment area to the sea and a week or more for the mud it’s picked up on the way to clean up. After rain you need to avoid dive sites anywhere near river mouths or harbours, as these will be the worst affected.
Provided you rug up properly and make good condition assessments there’s no reason why cool water conditions can’t provide some seriously productive diving.
As always the trick to successful spearfishing is adapting to meet the conditions and that is the key to consistently bringing home fish year round.
Learn your dive sites and get to know how different winds and tides will affect them. You only need a little stretch of coast and one rock holding fish to turn a slow day into a great one and remember that it could be this next one right in front of you.