Urbantrout Diaries 4: Spawning Time
This month it’s time for the trout to get down to it on Theo’s local River Wandle...
By early December, our city trout have started to spawn. For the last few weeks, a persistent northerly airstream has set up across the British Isles, funnelling bands of rain and plummeting temperatures down from the Arctic.
A hard core of grayling fishers put a little spike into sales of our ear-warming Urbantrout beanie hats, and the wild trout have taken notice too, drawn upstream by ancestral instinct and those vital extra inches of cold, oxygenated winter rain bubbling over gravel glides and riffles.
Here on the Wandle, it’s a curious fact that since we saw that first pair of trout cutting redds on New Year’s Eve in 2007, the peak of activity actually seems to have crept a little earlier as each spawning season rolls round. By mid November this year, one of the Wandle Trust’s catchment officers had already spotted the telltale signs of trout getting down to some concentrated gravel cleaning.
When I walked downriver the following afternoon, the trout were still there: two big fish cruising the daylight shallows like nuclear submarines, with their grey backs half out of water and clear wakes veeing off their dorsal and adipose fins.
Crouched behind some bankside bushes to watch, a sudden disturbance made me look downstream: something threw a wedge of water three feet into the air, and a second hook-jawed male came charging into the flotilla, unsettling their sense of purpose and leading them away into the white water under a little weir.
Under an arc-chrome shower of birch leaves, out there on the shallows, the early stages of a clean gravel redd were already plain to see. A three or four-pound hen trout can shift an impressive mound of flints, eroded knobs of slag, even half bricks or lumps of concrete, several feet downstream, and since watching this happen for the first time, I’ve speculated whether our platonic ideal of a feature-filled humped-and-hollowed river bed is partly created by salmonids at spawning time.
Not so long ago, the National Rivers Authority used to keep whole flood defence teams busy through the winter by sending them into rivers like the Wandle to flatten every one of those natural humps and hollows with heavy machinery. So you slowly start to wonder about city trout as ecosystem engineers: nosing into parts of rivers which may have been functionally troutless since the Victorian era or even before, throwing gravels around in a careful, careless spawning frenzy, and shaping them back to habitability for a whole web of river species.
But even the most energetic trout take time, and urban rivers need all the help they can get. Out on that river walk with a group of local partners, our catchment improvement officer was in the final stages of planning a major river restoration project. When the wet work finally happens in a few months’ time, we’re aiming to transform a wide area of muddy impoundment into almost an acre of new spawning and juvenile habitat, ready to start pumping a steady supply of little wild urban trout fry down the river in spring 2015.
The Wandle’s trout don’t know it yet, but all of their Christmases may be about to arrive at once…
Images courtesy Lysanne Horrox
ABOUT THE AUTHOR
Theo is a freelance marketing, fly-fishing and environmental writer. He’s also Chairman of Trustees of the Wandle Trust, and founding editor of Urbantrout.net a website dedicated to the urban fly-fishing and river restoration improvements.
Theo’s trailblazing book Trout in Dirty Places: 50 rivers to fly-fish for trout and grayling in the UK’s town and city centres was published by Merlin Unwin Books in 2012. His new book on invasive non-native species is due in May 2014.
Articles by the same author
- Brexit - What Are The Implications For The Environment?
- Urbantrout Diaries 9: A Year of Mending Urban Rivers: Part 3
- Urbantrout Diaries 8: A Year of Mending Urban Rivers: Part 2
- Urbantrout Diaries 7: A Year of Mending Urban Rivers: Part 1
- Urbantrout Diaries 6: Taking the Fight to Invasive Non-native Species
- Urbantrout Diaries 5: Wet Weather in Wincanton
- Urbantrout Diaries 4: Spawning Time
- Urbantrout Diaries 3: Discovering the Dour
- The Urbantrout Diaries 2: Bashing Balsam
- The Urbantrout Diaries: Spinners in South London