For farmers, there is probably nothing worse than waking up in the morning to find an invasion, especially one with an insatiable appetite. Recently a spate of farms in my local area of northern Tasmania have found themselves at war with a pest, a small caterpillar like grub called the Armyworm. They are called Armyworms for the fact they will eat out an area and then march out en masse to take over the new ground in search of new food. It’s on this army like march that some of these Armyworms will reach a river or stream and it is here they end up crawling out onto the edge of foliage and dropping off into the water where they float downstream. 
It’s at the river’s edge the legion of feasters on the move then soon becomes the feast and it starts raining these chewy little grub morsels down on the trout like gummy bear manna. The trout religiously start jostling for the best position along the river’s edge for the feast, lining up along the bank to be fed by this conveyor belt of food like starving patrons at a sushi train restaurant where they eagerly wait for the next tasty bit to come their way.
Some trout will take up prime position under the foliage and wait for that distinctive plop as the tasty grub takes the drop. These trout in anticipation move fast towards anything that hits the water and it soon gets an inspection and the taste test. Other trout will post themselves in a likely position for food items to pass by, usually any slightly protruding edge of the bank that juts out just enough to funnel the drifting armyworms into a narrower band is a good place to be. Trout are smart, why work too hard for your food when you can have it either raining down on your head or conveyed into your mouth.
All this make me think about my own smarts or sometimes lack of them and how that ravaging disaster for a farmer ironically can be a fly anglers win fall. Three weeks early a number of local news sites ran stories about farmers battling the increased damage from armyworm grubs. And here I was standing by the river watching this amazing event unfold as trout gulped down grubs in a frenzy. I was given the pre-warning it was there in the news and like most anglers, I just didn’t pick up on it and here I was bankside caught out without some sort of a grub fly. Our increasing crops and pastures have provided the ultimate food source that has fuelled various cycles of herbivorous insect and grub pest. Many of this pest and plagues, in turn, become an abundant feast for the many fish that inhabit the rivers and streams that wind through our farmlands. It really gets you thinking more so about types of crops that may be grown in your own local area and the cycles of associated agricultural pest that come with them and how that plague might turn into one of the best fishing sessions for the season.
Steven Ooi is a Tasmanian photographer who takes incredible shots of trout in his local waters. Be sure to check him out on Instagram @finripplemedia!
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