About the Scuds
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Class Crustacea, Order AmphipodaMany people mistake Scuds for crayfish and shrimp. But Scuds are only distant cousins to these species, and their only true common name is Scud.
Did You Know... 20% of the trout diet consists of Scuds, making them second in importance only to the chironomids (midges). Lakes with lots of Scuds produce amazing growth rates in trout.
What do Scuds look like?
If you look closely, scuds are actually quite different from shrimp and crayfish. They look quite a bit like a tiny armadillo, up to two centimeters in some varieties, much smaller in others. Only this armadillo ranges in colour from green to yellow and even blue. It has seven pairs of legs under its hard, segmented exoskeleton, and two pairs of long antennae. They move in a jumpy, uneven manner, sometimes swimming upside down.
Food for Thought... Scud colouring changes depending on the environment. Why would they tend to be light-coloured when weed growth in the lake is low?
Where do Scuds live?
Scuds like the shallow parts of lakes, usually fifteen feet or less, but they may be found as deep as fifty feet. They usually live in vegetation and under rocks.
What is the life cycle of the Scud?
Scuds have no pupal stage at all, and spend their whole lives under water. Click here to see the life cycle of a scud. And there are lots of them underwater in an average lake. A single pair of Scuds can produce about seven broods, perhaps more, totally around 20,000 offspring every year. The result? In the average lake, there are literally billions of Scuds under the surface!
Scuds will eat just about anything, including larger organisms, although they mostly seem to eat vegetable matter.
| Did You
Know... the colour of trout flesh comes from an orange pigment in Scuds called
carotene, the same pigment that gives carrots their colour.
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