An aggressive 4.2-metre long crocodile has been trapped at a popular fishing spot in north Queensland.

Rangers have trapped a 4.2-metre crocodile spotted chasing another croc at a popular fishing spot in north Queensland.

The huge reptile was one of two male crocodiles seen chasing a female crocodile near a boat ramp on a river south of Townsville.

Rangers laid floating traps in the Haughton River last week and managed to catch the big croc on Tuesday.

It will be relocated to a farm or zoo.

State Environment Minister Andrew Powell urged boaties to take extreme caution or avoid the area until the other crocs have been trapped.

“These are very large crocodiles and they are showing very aggressive behaviour,” he told reporters on Wednesday.

Recently a Port Douglas canoe club, north of Cairns, relocated its headquarters from a croc-infested waterway to a nearby beach.

The reptiles considered a threat to people in Townsville, Hinchinbrook, along the Cassowary Coast and in the Cairns region are relocated.

Under the state government’s croc removal scheme 56 crocs have been trapped and relocated since early 2013.

One of the biggest was a 4.5m croc caught in the Herbert River near Ingham in August last year.

Concerns have been raised that the scheme doesn’t work because other crocs may take over an area once one is removed.