Māori name: Hautere 
Scientific name: Trachurus spp  
All-tackle NZ record: 1.940kg  
Eating quality: Good, but usually used for bait!

Description

Jack mackerel are primarily used as live or dead baits by Kiwi anglers, although some anglers specifically target them for their eating qualities. In Japan, jack mackerel (aji) is often eaten raw as sashimi or cooked deep-fried (karaage) style.

There are three different species of jack mackerel, difficult to tell apart, swimming in NZ waters. They are little fish (generally caught between 15-30cm) that are fast-moving and prey on plankton and smaller pelagic fish like anchovies. 

Their distinctive feature is their unusual bony plates (scutes) which cover the lateral line and form a broad spiky keel at the tail. The colour scheme includes a silver-green back that fades to a creamy-white underside and a yellow tail.  

Jack mackerel belong to the family Carangidae, which also includes trevally, kōheru, and yellowtail kingfish. They can be distinguished from kōheru by their distinctive bony, kinked lateral line. 

Where to catch

Found right around NZ, jack mackerel school in midwater and range from bays to oceanic islands. They are often encountered in large schools at inshore depths, both over flat bottoms and around reefs. Good areas to start hunting out ‘jack macs’ are sheltered areas like harbours, bays, sandy drop-offs, and shallow reefs – often in depths between 5-25m.

Birds on the water (gannets, terns, and/or shearwaters) are a good mackerel indicator, and schools often show on your fishfinder as baitballs in midwater. They also congregate around man-made structures such as bridges and wharves, making them an accessible target for any angler.

When to catch

Jack mackerel can be reliably found throughout the year, although the schools tend to shift around a bit – therefore, where you found them a month ago might not be where they are now. In shallower coastal areas, large swells influence mackerel and often push fish out into deeper water. 
Although jack mackerel feed throughout the day, they become more active in the dark, making them a great prospect to catch when anchored up overnight. They are also attracted to lights, meaning wharves and city breakwalls are popular areas for keen aji anglers.    

How to catch

The most common method of catching jack macs is on a sabiki, a string of 3-6 small flies tied on tiny fine-gauge hooks. Keen live-bait fishers generally cruise around and find the bait with the fishfinder. Mackerel sign will either show up as big balls or small scattered shapes around mid-water. 

You’ll likely hook several fish on a single drop if you get onto a hungry school. Try to keep the sabiki flies moving. Normally, the best technique is simply to drop all the way to the bottom and then retrieve quite quickly, interspersed with a few jiggly pauses. This way, you cover the whole water column and keep the flies looking alive. 

At other times, they can be a tad fussy, so parking up with some berley in conjunction with tiny slivers of bait on the sabikis will help your chances. If you’re catching mackerel under lights at night, micro-softbaits (ajis) or very small jigs can be deadly.