On the Rotorua lakes, Taupō and lakes like them, summer trout go deep and sit at one depth. A downrigger takes your lure straight to that depth on a weighted cable and lets go when a trout strikes, so you fight it on light line with no lead. This guide covers the setup, finding the depth, speed and set-back, the lures to start with, rods and reels, lead line versus downrigger, and the rules.

Why a downrigger

Why use a downrigger for trout

Three reasons it out-fishes a flatline in summer.

Depth

The exact depth

The counter shows how much cable is out, so the lure runs at the depth the trout are holding and you can return to it every time.

Light

Light line, no lead

The ball does the work, so your own line can be light mono or braid. Nothing heavy is on the line when you fight the fish.

Release

A clean fight

The release lets go on the strike. The ball stays on the cable and the trout is on the rod alone.

01 · The downrigger

Scotty manual downriggers

Laketroller to Depthmaster

For lake trolling a manual downrigger is all you need. The Laketroller 1073 and Clamp 1071 suit small boats and weights under 4lb. The Depthmaster 1050 and Compact 1060 add a 23in boom, a depth counter and a rod holder for bigger boats and deeper lakes. The Scotty guide compares every model.

The mission
Put the lure at the depth the trout are holding
Best for
Small boatsLakesManual

The setup

The setup, part by part

What each part does and the sizes for lake trolling.

Mount

Mount it where you can reach it

The Laketroller 1073 comes with a side deck mount; the 1071 clamps on. Bigger units take a quick-slide bracket, gimbal or swivel base.

Ball

Ball size for lakes

Match the ball to the downrigger's rating. The Laketroller is rated for weights under 4lb, so a 3lb keeled ball is the match.

Release

The line release

Clip the release to the ball or cable. Set it firm enough to hold the lure, light enough to let go on a small trout.

Cable

Stainless cable

Standard on most units and hard-wearing. It can hum in the water and kinks if mistreated.

Braid

Braided downrigger line

Quiet, doesn't kink and has less blowback. It won't carry electricity, so it doesn't suit electronic voltage systems.

Stops

Beads and terminal kit

Stopper beads and a terminal kit protect the cable end and the ball snap.

Shop downrigger line and weights

Watch

Watch how it's done

Scotty | How To Use A Downrigger

Scotty's animated guide to how the cable, ball and release work together.

Video by Scotty Fishing & Outdoor Products, on their YouTube channel
Geoff Thomas - How to Use a Scotty Downrigger!

Geoff Thomas walks through rigging and using a Scotty manual downrigger on the lake.

Video by Geoff Thomas, on the Monster Distribution YouTube channel

Finding depth

Find the depth first

Common practice on the Rotorua lakes and Taupō. Your sounder is the final word.

Summer

The lake layers up

In summer a warm layer sits on top of cold water. Trout hold where the water is cool and has enough oxygen, often around the layer between, called the thermocline.

Sounder

Read the sounder

Many sounders show the thermocline as a faint band. Look for trout and smelt marks near it, then set the counter a little above the fish.

Spring

Spring and autumn

When the water is cooler trout are shallower, and harling or a short lead line works. As the lake warms, they move down.

Winter

Winter mixing

In winter the lake mixes top to bottom, so trout spread out and are often shallower. Some lakes close to boats in winter areas: check the rules.

Above

Run above the fish

Trout look up to feed. Set the lure a metre or two above the marks rather than below them.

Log it

Write down what works

Note the depth on the counter, the speed and the lure when you get a strike, and go back to it.

Speed and set-back

Trolling speed and set-back

Common practice, not hard rules. Adjust until the lure swims right.

1

Troll slowly

Around walking pace. DOC's Taupō trolling page says no faster than a walking pace. Watch the lure beside the boat before you send it down.

2

Set the lure back

Let out about 5 to 15 metres of line behind the ball before you clip it in. Go longer in clear, shallow water where trout are spooky.

3

Clip in and lower

Put the line in the release, lower the ball to depth on the counter, then wind the rod tight so it bends.

4

Watch the rod tip

A trout pulls the line free and the rod springs up. Wind fast to come tight, then play the fish.

5

Wind up the ball

Bring the ball up while the fish is played so the line can't tangle in the cable.

Compare

Lead line or downrigger?

Both put a lure deep. Each suits a different day.

Lead line

Simple and cheap

A lead-core line sinks as you let it out, so there's nothing to mount. Depth depends on how much line is out and how fast you go, so it is only approximate, and you fight the fish on heavy line.

Downrigger

Exact and light

Exact depth on the counter, light line and a clean fight once the release lets go. It needs a mount, and works best when the fish are holding at one depth in summer.

Shallow

When lead line makes sense

Spring and autumn fish in the top few metres, a boat with nowhere to mount a downrigger, or covering water at changing depths.

Deep

When the downrigger wins

Mid-summer trout sitting deep on the thermocline, light-line fishing, and going back to the exact depth that caught the last fish.

The rules

Licence and lake rules: Rotorua lakes and Taupō

Rules change each season. Check the current rules before you go; these are from the 2026/27 Eastern Fish & Game notice and DOC's Taupō rules.

Licence

Two different licences

A Fish & Game licence covers the Rotorua lakes and the rest of NZ, except Taupō. Lake Taupō needs a Taupō fishing licence from DOC.

Fish & Game Eastern regulations 2026/27

Rods

One rod each

Both notices allow one rod and line per angler, with up to 3 lures on it. Set rods are allowed from a boat on the Rotorua lakes.

DOC Taupō rules

Taupō

Single hooks on Taupō

On Taupō each lure may carry only one hook, and it must be single-pointed. Swap trebles for a single hook. You can't troll within 200m of the stream-mouth landmark posts.

DOC Taupō rules

Rotorua

Rotorua lakes

Minimum size 350mm and 8 trout a day, no more than 2 of them brown. No fishing between midnight and 5am. No fishing from an unanchored boat within 200m of a landmark pole.

Fish & Game Eastern regulations 2026/27

Seasons

Open seasons and winter areas

Lake Rotorua and Okareka are open all year. Tarawera, Rotoiti and Okataina open 1 October to 30 June, and boats are barred from their winter shoreline areas 1 July to 1 October.

Fish & Game Eastern regulations 2026/27

Banned

Where downriggers are banned

Downriggers, paravanes and metal-cored or wire lines are banned on Lakes Waikaremoana and Waikareiti. Check each lake's notice before you go.

Fish & Game Eastern regulations 2026/27

South Island

South Island trolling lakes

The main trolling lakes by Fish & Game region, from the 2026/27 regulations. A Fish & Game licence covers them all, and everywhere it's one rod and line each with up to 3 lures.

OtagoWakatipu, Wānaka, Hāwea, Dunstan
LakeSeasonDaily bagSize limitBoats and gear
WakatipuAll year2 trout, 4 salmonNo minimumBoats allowed; motor boats keep 100m from anglers on the shore. Closed in Queenstown Bay and within 100m of the Walter Peak wharf.
WānakaAll year2 trout, 1 salmonNo minimumBoats allowed; motor boats keep 100m from anglers on the shore. Closed within 150m of the Wānaka wharf, the marina jetty and the shore between.
HāweaAll year2 trout, 4 salmonNo minimumBoats allowed; motor boats keep 100m from anglers on the shore.
DunstanAll year2 trout, 1 salmonNo minimumBoats allowed; motor boats keep 100m from anglers on the shore.
SouthlandTe Anau, Manapōuri
LakeSeasonDaily bagSize limitBoats and gear
Te AnauAll year2 trout; region limit 1 salmon and 4 sports fish a dayNo minimum or maximumNo boat or downrigger rule listed. Some Fiordland areas need a Clean Gear Certificate: ask Southland Fish & Game.
ManapōuriAll year (incl. Waiau Arm)2 trout; region limit 1 salmon and 4 sports fish a dayNo minimum or maximumNo boat or downrigger rule listed. Some Fiordland areas need a Clean Gear Certificate: ask Southland Fish & Game.
Central South IslandBenmore, Aviemore, Tekapo
LakeSeasonDaily bagSize limitBoats and gear
BenmoreAll year4 sports fish, trout and salmon combinedTrout: none. Salmon: 250mmNo boat or downrigger rule listed.
AviemoreAll year4 sports fish, trout and salmon combinedTrout: none. Salmon: 250mmNo boat or downrigger rule listed.
TekapoAll year6 sports fish, no more than 4 trout or 4 salmonTrout: none. Salmon: 250mmNo boat or downrigger rule listed.
North CanterburyColeridge
LakeSeasonDaily bagSize limitBoats and gear
Coleridge1st Saturday in Nov to 30 Sep4 sports fish, trout and salmon combinedTrout and salmon: 300mmFishing from boats allowed; boat use itself is set by the council.
Nelson/MarlboroughRotoiti (Nelson Lakes), Rotoroa
LakeSeasonDaily bagSize limitBoats and gear
Rotoiti (Nelson Lakes)All year2 troutNo minimumDownriggers permitted. No fishing from a motor-powered boat within 100m of the Travers River, Coldwater Stream, Black Valley Stream or Buller River mouths.
RotoroaAll year2 troutNo minimumDownriggers permitted. No fishing from a motor-powered boat within 100m of the Sabine, D'Urville or Gowan river mouths.
West CoastBrunner, Kaniere
LakeSeasonDaily bagSize limitBoats and gear
BrunnerAll year2 brown, 2 rainbow, 1 salmonNo minimumNo boat or downrigger rule listed.
KaniereAll year2 brown, 2 rainbow, 1 salmonNo minimumPut-and-take fishery stocked for lake-resident salmon. No boat or downrigger rule listed.

Source: Fish & Game 2026/27 South Island sports fishing regulations, each region's Schedule 2. Downriggers, paravanes and metal-cored or wire lines are banned on Lake Alexandrina (Central South Island). Rules change each season: check the current notice before you go.

02 · Rigging

Releases, weights and line

Scotty and Monster Fishing

The parts that wear out or get lost: release clips, keeled balls, stainless cable, braided downrigger line and the beads and snaps that hold it together.

The mission
Finish the rig
Best for
ReleasesWeightsCableBraid