Last month I wrote praising the general run of anglers for their maturity and responsibility in the way they have learned to appreciate native and other fish and in particular to practise catch and release when fish aren't required for the table.

While I still stick to this I was swiftly reminded straight afterwards of the other side of human nature, the one dominated by greed, insensitivity, irresponsibility or simple defiance of the law.

It started when a group of anglers noted a fellow acting suspiciously on the Murrumbidgee River upstream from Burrinjuck Reservoir. They contacted the local NSW Fisheries officer at Yass and when he investigated he found the fellow using illegal mesh nets to trap Murray cod and golden perch, fish which undertake important migrations up and down this section of river. This was in an area likely to contain protected animals such as Macquarie perch, trout cod, platypus, water rats, tortoises and a wide variety of birds.

The 65-year old was charged, brought before Yass Local Court and fined a nice pocket-emptying $4225.

The bad part of all this is the appallingly destructive behaviour of the netter, killing fish and possibly other animals indiscriminately. But the good part is that anglers took the time and effort to observe, then report their suspicions to the proper authority.

They didn't try to apprehend or interfere with the netter; instead they provided enough information for the professionals to do their job. And that's the way it should be.

If you see something suspicious, call your local Fisheries office straight away – not hours or days later. If you don't know that number, call the Fisheries Watch Hotline on 1800 043 536. It’s a free call.

Collecting the right information is important. Note the exact time, nature and location of the suspect activity, details of the build, hair colour, clothing and other characteristics of the people involved, the equipment being used and the make, model and registration numbers of boats or motor vehicles involved or parked nearby.

The more detailed and accurate information you can provide, the more effectively the professional inspectors can do their job. They are trained professionals but you can be their eyes and ears.

Inspectors usually have large geographic areas to cover and can only work so many hours in a week. You can make them more effective and useful by working with them at every opportunity.

Incidentally, the same inspector later found four anglers fishing in the Murrumbidgee River without valid licences. That cost them $800 in fines and they are still whingeing about it and the fact that they didn't expect to get lumbered because they were 29km off the main road.

You will get caught no matter how far off the main road you are. Stop moaning and buy a licence like the rest of us and remember that it was anglers themselves who several years ago voted overwhelmingly in favour of a recreational fishing licence because they recognised the good that that would do angling. But only if we all play the game and throw in a few bob each year for a licence.

Curiously, it is sometimes catching a fish accidentally during a closed season that makes people realise the value and significance of releasing fish. The Murray cod closed season is a good case in point.

It is illegal to catch and keep a Murray cod in NSW and the ACT during September, October and November. This period corresponds to the fishes’ most likely breeding period, during which they act in splendidly silly fashion and are likely to take almost any lures or baits offered to them.

It's to protect them against themselves, as it were. It's obviously important maintain a proper breeding stock of fish, in NSW waters, and although cod do not breed where they are stocked in the urban lakes in the ACT, the closed season is imposed to maintain parity of legislation with surrounding NSW and also on the slim chance that the fish may one day migrate downstream to waters where they could breed.

In a strange juxtaposition of events, anglers fishing with legally-allowed lures for redfin, silver perch, golden perch or even trout during the closed season for cod probably have the best chance all year of catching one.

That's great in one sense because for many anglers catching a cod is the epitome of success – a big cod is the Holy Grail of freshwater angling. Having caught it, however, they know they are required to look after it and release it as unharmed as possible.

So they do just that and therein is sown the seed of catch and release. From then on it is simple; you catch a fish and you release it.

‘Losing’ the fish is no big deal. In fact you even feel good about it; so good that when the open season comes around again you are mentally attuned to catch and release and that's how you fish, even though you could kill and keep a cod if you wanted to.

It’s a nice little cycle of conservation-style fishing that all started with accidentally hooking a fish during a closed season.

It’s a perversity of the law that has worked very much in favour of the fish – not just cod but lots of other species where anglers get their satisfaction from the capture and perhaps a trophy photograph but not a dead fish carcass.

Fishing in the region has been pretty good. Continuing flows in the high-country trout streams, especially the Thredbo, Eucumbene and Murrumbidgee rivers, have resulted in some excellent dry-fly fishing.

A few browns and a lot of rainbows, which normally would have returned to the lakes this year stayed much later than usual upstream of Eucumbene, Jindabyne and Tantangara, have provided good sport on White Moth, Humpy, Hairwing Coachman, Tups Indispensable and various grasshopper patterns.

The lower streams are a different picture. Many have had good flows following the breaking of the drought but a lot of the fish have died. They have been restocked but it will be next season before the fish are of worthwhile size.

An additional hazard is that a number of the streams have been invaded by carp, which worked their way well upstream during the drought and have since established themselves in water we have always though of previously as trout-only. Whether they stay there in better water flows remains to be seen.

The big trout lakes continue to provide very satisfying fishing. Early morning trollers have taken some big browns and Flatfish, Wonder Crocodiles, Tasmanian Devils in reds, blues and yellow-winged, Attack minnows, Baby Merlins and Strike Pro Pygmies all have been useful.

After about 8am it is worth going deeper and concentrating more on rainbows with lead-core line or a downrigger, with the fish generally dropping down initially to about seven metres, then 10 to 15 metres as the sun gets directly above.

Bait fishers have fared well with PowerBait, bardi grubs, wood grubs, scrub worms and mudeyes, again in the early morning and late afternoon and evening.

Some excellent Murray cod and golden perch have been taken from Googong, Burrinjuck and Wyangala reservoirs where water levels are a lot higher than during the drought years, although abstraction for downstream irrigation and power production is still a worrying spectre.

The more stable Canberra lakes have also been productive for cod and perch and also for larger redfin – bigger than we have seen in previous years. We may not like some of the redfin’s habits but they do provide good fun on lure, bait and fly and they are one fish around here worth keeping for the table.