Gemini
CC Moore
Ben Gratwicke Features
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Should you break the ice or not?

We ask top fishery owner, Ben Gratwicke, should we break or not break the ice?

“Wind the clocks back a few years to the winter of 2010/11 and lakes and reservoirs were frozen solid for weeks, even months.

“The question that is often asked is: should you break the ice on a pond or lake to protect Mr. Carp or any other fish for that matter? The answer: maybe. If your pond or lake freezes for a few days then you really have nothing to worry about but if that rolls into weeks or months then that changes things a lot! The two scenarios are going into their third week of being completely frozen with no let up on the horizon.

Scenario 1

“The lake is 120-acres, very open and wind swept, has an average depth of 10ft, is spring fed via a rich gravel seam and has a stock of 200 fish with a small shoal of big bream as well as your usual perch and eels. In this scenario you have nothing to worry about.”

Scenario 2

“If on the other end of the scale your lake is a two-acre weedy estate lake, surrounded by trees, has an average depth of 4ft and has a head of 400 fish averaging mid-double, a good head of silvers, tench to 6lb and is fed sporadically via farm run off and rain water I should pay attention. Once a lake becomes frozen the following things happen…

- “Light levels are decreased especially coupled with snowfall. This in turn stops algae photosynthesizing. The algae then dies and uses up valuable oxygen within the lake.

- “No wind can blow on the water. Without wind on the water, the water body is not circulated and oxygen is not spread through the water column or allows oxygen exchange.

- “No gas can escape from the lakebed. Where oxygen levels are low within the water body, anaerobic bacteria partially breakdown the sediment on the lakebed, as this process occurs they expel hydrogen sulphide (this is the horrible egg smell you get in that really black silt). Hydrogen sulphide is harmful to insects and fish as well as toxic to aerobic bacteria. Usually all this gas escapes unless its trapped under a thick layer of ice in which case it dissolves back into the water making the water highly toxic.

“Now, for scenario 1, the above is not a problem, as it has a huge volume of water with a low stock density and a constant supply of fresh water running through it and due to its gravely nature very little organic debris.

“Scenario 2 is a very different outcome all together. With very little light in a shallow rich lake with a heavy organic load, big stock density, no regular fresh water running through and a very silty nature I would be concerned if the lake stayed frozen solid for more than two weeks.”

My top tips

01 “Try to keep an area free of ice to allow gas to escape, keeping an area free will also aid with thawing when it comes.”

02 “Keep a good flow of water running through your lake if you can.”

03 “If you can’t get water running through, maybe get some type of aerator to move the water and aerate it.”

04 “Do NOT feed the fish if you are having trouble.”

05 “And most importantly, DO NOT put yourself at risk.”