Reel Life December 2025 - Eastern

Hot Weather Changes The Game

A heatwave that has smothered the North Island early in December has had a rapid and dramatic effect on trout behavior, causing anglers to change tactics to get results.

Image above: Jeff and Robyn Tuavera after a successful day jigging on Rotoiti  

Surface temperatures on the main Rotorua lakes have risen to over 20 degrees during the heat of the day and a thermocline is well formed and visible on sonar units about the 12 to 15m mark. Stream mouth fishing, where colder inflowing water provides refuge for trout on Lake Rotorua and some of the Waikato hydro lakes, has taken off. Trout are comfortable in temperatures around the mid-teens and will actively seek out cooler water once temperatures reach 19 or 20 Celsius. Fish at these locations don’t tend to be too fussy as warm water increases their metabolism. A wet fly, such as a small Wolly Bugger, generic smelt fly or nymph slung under an indicator will all do the trick, as will spinners and softbaits.

Water temperatures are an important factor in locating trout during the summer and lake temperatures can be seen via a Regional Council monitoring page found here. The page takes a few seconds to load, but simply select the dropdown for the lake you want, and the data is shown in a graph. See below for our Boat Fishing How-to that will teach you more about temperatures, the thermocline and how to locate fish.  

On the deeper Rotorua lakes thick layer of ‘clutter’ can be seen on fish finder units down to about 15m where the water starts to cool. This is perfectly normal and is made up of things such as algae, zooplankton, smelt and sometimes trout which are foraging there. Fish can often be found sitting just below this layer, actively ambushing smelt from below. There are also many fish sitting feeding near the bottom in 20+ metres of water which will come up to have a look at softbaits and flies.

Insert image: Thermocline and fish     

Deep trolling gear (10 colours of leadline), will still get you down to where the fish are currently sitting and downriggers enable exact depths to be targeted. Shallow trolling, now that the temperatures are rising rapidly, will only be effective for a couple of hours after dawn, after which the fish will move deeper.    

Boat Fishing How-to    

If you are new to boat angling, and want to learn more about this stuff, consider booking a spot in our Boat Fishing How-to, on Saturday, January 10^th 2026. It’s a beginner's guide to learning about things like the thermocline, smelt and trout behaviour, all of the methods of catching fish on lakes, tips on targeting fish, lure selection, fish finders, rigging your gear and even boning and smoking your catch. It’s free, but spots are limited. Get more information and book by clicking here.

The Boat Fishing for Trout How-to will be held in January 2026

Taranaki Lake to be Drained

Taranaki’s lake Rotomanu, in which the invasive freshwater clam (Corbicular) was found in November, is to be drained to allow a science team to study the incursion announced Taranaki Regional Council recently. This is an important reminder to all users of freshwater resources about the need to clean equipment between waterways. The old mantra CHECK, CLEAN, DRY applies here and it’s not difficult to do. The Rotorua lakes also have an MPI Controlled Area Notice (CAN) applied around cleaning for Lake Okataina and if vessels have been in the Waikato River within the previous 30 days. See here for more.        

Catch and Release during Hot Weather

With summer water temperatures likely to rise further it’s a good time to remember to take particular care of your catch when fishing in water above 20 degrees Celsius. Fish in cooler sections of rivers, lakes and streams or at cooler times of the day to prevent undue stress from occurring when releasing your catch. And, always handle fish well, with minimal time out of the water (aim for less than 5 seconds), and with wet hands. Take a look at this article on good C&R practice: https://782c075b.flowpaper.com/FGIssue61WEB/#page=32

New Access Mapping System

 A new online mapping system has just been adopted by the Eastern Fish & Game Region (and several other regions). It is still in development, but is already a useful tool for finding fishing locations and the regulations that apply to that spot. The filter tool (top right of screen) enables users to focus on the access or fishing style they are interested in.
Select here to view

Don’t forget to CCD!

The new season is a good time to remind everyone of our need to Check, Clean and Dry gear between waterways. Pest organisms are sadly on the increase and the precious resource we all love is at risk. Please remember to CCD between your fishing trips, follow the instructions of the Regional Councils and MPI.

Datawatch tagged Trout

Tagged trout can now be entered online. Entries go into the draw to win one of 10 free whole-season fishing licences: https://www.surveymonkey.com/r/QCH5ZR6

Eastern Region Fishing Diaries – All lakes and streams

Fill in your fishing diaries here to help us manage the Eastern Fish & Game region. Participants go in the draw to win a $100 voucher from Kilwell: https://www.surveymonkey.com/r/QRSD7D3