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Fish can actually shrink in cold water

Hot off the news wire this week: Trout shrink! A group of Norwegian and Finnish scientists have recently observed that during cold temperatures, Salmoniods can reduce their body length up to 10%.

Hot off the news wire this week: Trout shrink!

A group of Norwegian and Finnish scientists have recently observed that during cold temperatures, Salmoniods can reduce their body length up to 10%.

It's believed that they do this by reducing the gel in their vertebral disks.

Add this new revelation to the fact that a fish's whole metabolism slows down in relation to dropping temperatures, along with knowing that they can also change their skin colour to adapt to their surroundings -- science has documented that trout can change colour completely in 36 hours -- and one gets a glimpse into whatscience has named "functional ecology."

Amazing creatures these fish, which are also able to change their colour to hide from predators, regulate their food intake and digestion with their metabolism, along with conserving energy by reducing their body size.

After reviewing all this data, one question stands out in my mind: How big, actually, was my friend Dave Rice's 44-inch, fly-caught Thompson River Steelhead before it shrank?

One can only imagine.



The report

The ice is off our Lower Mainland lakes but it will take a day or two of sunny skies to get the fish feeding actively again.

If you are going try a slow retrieve or troll, use Big Black, Woolly Bugger, Micro Leach, Sixpack, Dragonfly Nymph, Halfback, Doc Spratley or Zulu.

Our Lower Mainland beach and estuary fisheries for sea-run cutthroat are likely your best bet until all the high water recedes.

Try Epoxy Minnow, Tied Down Minnow, Muddler Minnow, Clouser's deep Minnow, Lioness, Grizzly King, Mickey Finn, Coachman, Knudson's Spider, Zulu, Purple Joe or Borden Special.

The Fraser River is slow to fair for cutthroat and dolly varden. For cutthroat try Rolled Muddler, Mickey Finn, Eggo, Tied Down Minnow, Epoxy Minnow, Winter Stone, Flesh Fly, Professor, Lioness, Coachman, Zulu, Chez Nymph.

For dolly Varden try: Large (#4 to #1) Eggo, Dolly Whacker, Bucktail, Epoxy Minnow, Big Black, Muddler or Zunker.

The Vedder River should be fishable, and good for steelhead, dolly varden and rainbow, by the weekend.

For steelhead try big Black, Popsicle, Steelhead Nightmare, Polar shrimp, GP, Thor, Squamish Poacher, Kaufmann Stone, Purple Peril, or Eggo.

For rainbow try: Rolled Muddler, Mickey Finn, Eggo, Flesh Fly, Kaufmann Black Stone, Black Gnat, Zulu, Chez Nymph, Big Black, Sixpack or Renegade.

The Stave River is good for rainbow and cutthroat.

The Chehalis River is fair for steelhead and cutthroat.

The Harrison River is fair to good for cutthroat and rainbow.