KNOWING how to measure your catch accurately is important to ensuring it complies with Queensland size limits.
Queensland Boating and Fisheries Patrol district manager Brett Depper said there was often debate among fishers about how to correctly measure their catch.
"The correct way to measure a fin fish is lying on their side and measuring from the tip of their snout to the end of their tail," Mr Depper said.
"The fish should not be manipulated in any way when measuring. For example, fishers shouldn't pinch the tail together to lengthen a fish's overall length.
"A sturdy ruler or coil tape measure with an end stop on it is the most accurate tool for measuring fish.
"By having an end stop, it means the fish can be put against the edge for accuracy.
"Measuring devices which are adhesive or flexible should only be used as a guide.
"Stick-on rulers and similar devices sometimes shrink when exposed to the weather so are unreliable and could give an incorrect measurement.
"If a fisher catches an undersized or unwanted fish they should return it to the water immediately, taking as much care as possible to avoid causing the fish any injury."
Mr Depper said mud crabs were measured from point-to-point across the widest part of the shell and must be a minimum size of 15cm.
Blue swimmer crabs are measured from the notch immediately forward of the base of the largest lateral spine on one side of the crab to the notch immediately forward of the base of the large lateral spine on the other side of the crab, and this notch-to-notch measurement must be a minimum of 11.5cm.
"The easiest and most accurate way to measure a crab is with a crab gauge, which can be found at bait and tackle shops," Mr Depper said.
"Recreational fishers should also remember that female mud and blue swimmer crabs are protected in Queensland."
If you suspect illegal fishing, whether you see it in person or online, report it to the Fishwatch hotline on 1800 017 116.
For more information on Queensland fishing rules, visit www.fisheries.qld.gov.au, call 13 25 23 or download the free Qld Fishing app from Apple and Google app stores.
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