Fishing the New Zealand Mouse Hatch

A mouse-eating New Zealand giant.
A mouse-eating New Zealand giant.Field & Stream Online Editors

Do you see the mouse in this photo?

Still don't see it? Here's a hint. The fish ate it. Don't worry it took me a while too… A bit on the gross side, eh?

Gross, but oh so cool if you like fishing mice patterns on top for trout. The past few years I've really gotten into fishing with the little rodents. So when fly shop owner and fly tier extraordinaire Stu Tripney sent me this photo I had to ask him about the "Mouse Hatch" that's supposedly going off down in New Zealand where Stu lives and runs his business. It seems every few years there's an overabundance of the little rodents way down south and it can make for some spectacular fishing. Here's what Stu had to say about the matter.

FLY TALK: Is the mouse "hatch" really a real thing?

STU: We as fly fishermen and women, seem to call any mass of fish food a hatch. Amongst the beach trees where it all starts, although I have never found any mouse eggs or discarded shells. What we do get sometimes is plauges of mice, more rodents than normal…

FLY TALK: Does it happen every year?

STU: Yes every year there are areas where the population of rodents is greater than others. Though in certain years if everything in nature comes together there can be a much larger explosion of rodents. This seems to be anywhere from five to eight years and that is when the big rodent plague happens.

FLY TALK: Tell us a little about it I you don't mind?

STU: There are always mice and rats around the countryside, but in certain years there can be more than normal. This is when some fun can be had during the day fishing with a mouse pattern fly… Watching a big brown or rainbow gently lift up from the bottom in gin clear water and sip down the large fly is incredible. Though fishing during the night produces the best results. Often, some people will scout out a lake, surrounded by beach trees during the day and put little markers were they can stand and get a clear back cast when they return for a night of mousing.

FLY TALK: What causes it?

STU: It is caused when all the beech trees flower at once and then seed en-mass. In turn there an abundance of food and rodents throughout New Zealand take the opportunity to increase their numbers.

FLY TALK: Do you really notice more fish eating mice these years than say a regular year?

STU: Most definitely, This is when you see very fat and heavy fish. This is when most people have a chance of breaking the 10lb trout mark regarded by many kiwis as the ultimate trophy trout.

FLY TALK: What's the most mice you've ever heard being found in one fishes stomach?

STU: Twenty one mice.

FLY TALK: What's the craziest mouse/fishing story you can give us in a few sentences?

STU: I don't have any crazy mouse stories, just plenty interesting ones. Like the guys who came into my shop to show me a few photos of a fish they had caught recently. It was around eight pounds in weight and was in top mouse eating condition. When the guy netted the fish, he then went to look at the fish and take out the fly. Putting his hand down into the net he jumped back with fright as there was a huge long rats tail hanging out the trouts mouth. His friend thought it was all rather hilarious when his mate got the fright and threw down the net. Realizing it was not a snake, he removed his fly. It was amazing that the fish had just swallowed a big rat and still wanted to eat a small nymph.

FLY TALK: Do you have a secret mouse fly?

STU: Yes I have my Bionic Mouse fly that I may release this year...