Mouse Plagues and Cicadas

I saw the trailer for a new movie from the team at Gin-Clear Media called The Source - New Zealand and was intrigued not only by the high quality product that I've come to expect from this media tribe but by a few of the details I had read on the Gin-Clear blog as well. I asked Nick Reygaert for a little more explanation and he was kind enough to shed light on things. First let me start by sharing the written excerpt that got me thinking:

"If ever there has been a summer to make a New Zealand fly fishing movie the last 12 weeks have been it. The weather has been fantastic and the fish have been in superb condition thanks to a mouse plague that happened earlier in the year. Once we saw the size of some of the fish being caught we made the decision to begin filming The Source - New Zealand immediately, a full 12 months earlier than planned. In the end it was an easy decision, this summer was basically a once in a decade chance to film fish of epic proportions. The filming began with a trip with big fish hunter Silvio. The timing of the trip was paramount as we intended it to coincide with the first hatch of cicadas. Big fish tend to go a bit silly when the first of these big insects hits the water and previously hard to catch fish will totally lose their heads and smash dry flies with the reckless abandon of a fingerling. We got very lucky! We hit our chosen rivers at exactly the right time. The fish were moving up to 3 meters to intercept our cicada imitations. These rivers all had a mouse plague earlier in the year and the fish were carrying an extra 2 to 3 pounds of weight."

After reading this I had to understand this thing about the "mouse plague" better. Was this mouse hatch something that an angler could predict? I figured the Way Upstream community might be interested to know too. Nick sent me this explanation by email:

"The mouse plague is a largely misunderstood phenomena, it happens because the beach trees bare fruit every five years or so and this causes an explosion in the number of mice around. When there are lots of mice around they become an important food source for large trout as they are continually falling in the water. Trout put on as much as 1-2 pounds of weight for every month the plague lasts. The big misconception is that these fish are regularly taken on mouse flies during the day, it is unusual for these large fish to be fooled by a mouse pattern during the day and it is much more productive to fish with nymphs or dry fly for these fish. The reason that the mouse plague is such a highlight for NZ fishers is that fish that have been feeding on mice are bigger and in fantastic condition - 7 pounders become 10 pounders! It pays to note too that mouse plagues tend to be very localized. The trick is to find the small areas that have had lots of mice and then target the rivers/lakes within these areas. It takes lot of leg work and local knowledge to get it right but when you do the results are spectacular."

I think it's fair to say that this film is going to contain some rare and special moments. Look for the full length release this July. Have a peek at the 2 minute trailer and consider making plans to fish New Zealand someday. You just might want to pay special attention to beach tree fruit and cicada hatches before you go.



Photos by N. Reygaert Mouse illustration by El Pescador