Match the hatch – surface lures for Murray Cod

I cast my big jointed surface lure to edge of the river and it landed with a distinct SPLOOSH. Within a couple of seconds there was a second SPLOOSH. A water dragon had left its sunny rock and plunged into the water nearby. It raced over to the lure and started to give chase as the lure blipped and blooped back towards the boat. As both the lure and water dragon (now in hot pursuit) passed over a submerged boulder we all held our breath. Surely one of them was about to be inhaled from beneath by a hungry Murray Cod.

Targeting Murray Cod on surface lures is probably the fastest growing segment of the freshwater scene in southern Australia. Instead of peppering likely logs and rocks for cast after cast with spinnerbaits hoping to ‘annoy’ a Cod into striking, there is a window where these amazing fish actively hunt their prey and take them down (literally) with violent surface strikes. It’s interesting to think about what the lures are imitating in this scenario; is it a white-tailed water rat, a water dragon, a snake, a small duckling!?

The more time I spend on our inland freshwater rivers, the more I’ve come to appreciate the unique ecology of these systems. What do I mean by ecology? According to the dictionary definition “the branch of biology that deals with the relations of organisms to one another and to their physical surroundings”. That pretty much hits the nail on the head.

Take our last trip chasing cod on surface lures. 1 hour before sunset, water dragons were flinging themselves into the water and chasing our lures. It happened time after time. Kudos to Lee, who managed to get some great photos of this happening. I would speculate that the dragons were either trying to eat the lure (although the lures were 110mm long), breed with the lure, or chase it away as part of a territorial response. The latter seems the most likely unless water dragons have developed a taste for gaudy yellow and red lady lizards. And according to wikipaedia, males are known to be territorial, and in areas of higher population density … exhibit displays of aggression toward other males including posturing and chasing. That settles it, the males are defending their patch from intruders. At least the lures are fooling the dragons.

30 minutes before sunset, the same phenomenon was still occurring. Water dragons were launching into the water to give chase to our pesky lures. By now, the sun was getting very low and the shadows from the gorge covered the entire water. From experience we know this is the ‘magic hour’ and any minute now, either the dragons or the lures would be engulfed by a Murray Cod in waiting.

Nothing.

But around 15 minutes before sunset (don’t forget there is still around 30 minutes of light between sunset and ‘last light’) the dragons suddenly refused to enter the water. They would glare at the lures from their rock but they never jumped in from this moment onwards. Not once.

It was about 10 casts after this, after this invisible environmental switch had been flicked, that Lee’s surface lure was absolutely smashed by a cod as it passed over some likely looking rocks. How the dragons suddenly knew that it wasn’t safe to enter the water is beyond me.  This is what I mean by ecology. A water dragon that enters the river when the cod are feeding makes no babies and is lost from the gene pool. The two creatures have obviously co-evolved to share the river … Nature is amazing ain’t it?

As the sun continued to fall we ended up with 5 cod on surface lures.

So one of the keys then to a good surface lure for Murray Cod is to have an action that mimics a swimming water dragon.  Match the hatch as the cliche goes. Obviously this is nothing new to lure makers, those big plastic bibs on Mantis, Cod-Walloper and Cod-Seeker lures all have essentially the same action. They lurch from one side to the other while making lots of splash and bubbles. Add a jointed body (two bits of wood connecting by a metal ring) and you get the seductive waggle of a water dragon in full flight across the top of the water.

These lures certainly catch fish, particularly Cod in the 60-90cm range, but are they big enough? Typically these lures come in 80-120mm sizes.  But referring again to wikipaedia for a description of water dragons; “including their tails, which comprise about two-thirds of their total length, adult females grow to about 600mm long, and adult males can grow slightly longer than one metre”. From this we can deduce that the body length (not including tail) of a fully grown female is about 200mm long and a male perhaps 300mm long.

Enter the over-sized lure. On the grapevine, many of the keenest cod anglers are throwing huge surface lures typically 300-450mm long. From all accounts they are especially effective on the bigger fish.  I guess it’s not surprising when you consider the size of the prey they are chasing and the amount of energy a fish might expend in giving chase and those violent surface strikes. Energy in – energy out.

So there you have it. Match the hatch, fish the magic hour and you’re in with a chance. But if the water dragons are still happily entering the water it might be time for a spinner bait. For those aspiring lure makers out there, I think there is a niche for a 200mm jointed lure with a long tail extending from the rear treble … just saying 🙂

Thanks for reading

Graz

PS In case you haven’t seen it, there is a cool little video here of the session in question complete with a surface strike captured on video.