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Identifying the Canadian Nightcrawler Worm

Vermicomposting is fun, challenging, and faster than hot composting. I compost with blues, red wigglers and European nightcrawlers.

Large Canadian Nightcrawler With Blue Ruler

Large Canadian Nightcrawler With Blue Ruler

Canadian nightcrawlers are on of the largest commonly available worms. They are sometimes called "dew worms" because they are sometimes found outside early in the morning, when there is morning dew on the ground and nearby plants. The scientific name for them is Lumbricus terrestris. Other names include "lob worm" or just "nightcrawlers."

Despite the name, Canadian nightcrawlers are believed to have originated in Europe.

They are not great for vermicomposting, however. They are more solitary worms compared to red wigglers, euros, African nightcrawlers, and even blue worms.

Canadian nightcrawler with Alabama jumper with ruler for scale

Canadian nightcrawler with Alabama jumper with ruler for scale

Size

Canadian nightcrawlers are large. Larger than most other worms with which you will come in contact. The one pictured below stretched to over 7 inches long. They are about as long as African nightcrawlers, but much thicker. They dwarf European nightcrawlers in both thickness and length. They are much longer and thicker than both red wigglers and Indian blue worms.

Canadian Nightcrawler on Ruler, Red Wiggler Above

Canadian Nightcrawler on Ruler, Red Wiggler Above

Identifying Characteristics of Canadian Nightcrawlers

In addition to their size, Canadian nightcrawlers also have a number of other characteristics that will help you identify them.

Canadian nightcrawlers are:

  • About as thick as a pencil
  • About 6–8 inches in length
  • Obvious, raised clitellum
  • Rounder on head size
  • Flatter on tail side
  • Spade-shaped tail
  • Dark purple color on head
  • Get lighter in color towards the tail
Closeup of Canadian Nightcrawler Flattened, Spade-Shaped Tail

Closeup of Canadian Nightcrawler Flattened, Spade-Shaped Tail

Environment

Canadian nightcrawlers like it pretty cold. They live in about 60°F soil year round. They can be kept in bins, if the environment can be kept cold enough. They need lots of decaying plant matter, like leaves and grass clippings, in their environment. They do not do as well as other composting worms at breaking down food waste.

I am currently attempting to see if Canadian nightcrawlers can survive at all in Florida temperatures. If I see any success, I will run a more formal test. During the summer, the temperature will reach 95°F, which will certainly make the soil greater than 60°F.

As with most worm species, Canadian nightcrawlers should be kept shaded from the sun. They need some moisture in order to help oxygen exchange, but too much water isn't good either. As a general rule, if there is standing water in your bin, you have too much liquid. Adding extra dry debris or bedding will help absorb the excess water.

Canadian Nightcrawler vs European Nightcrawler

Canadian Nightcrawler vs European Nightcrawler

Movement

Canadian nightcrawlers move somewhat slowly. They move similarly to red wigglers and European nightcrawlers. They generally move forward in a wavelike pattern, stretching out the front have of their body, then dragging the rest of their body forward. This is dissimilar to Alabama jumpers and Indian blue worms.

Canadian Nightcrawler and Alabama Jumper

Canadian Nightcrawler and Alabama Jumper

Where to Purchase Canadian Nightcrawlers

The most likely place to source Canadian nightcrawlers will be a bait and tackle shop. I was able to purchase 12 nightcrawlers for $4.50.

Due to their size, Canadian nightcrawlers make excellent fishing bait. They are much easier to pierce with a hook, compared to African and European nightcrawlers. They are almost too large for many small hooks, making them a tempting target for fish.

Canadian Nightcrawler Underside, Showing Clitellum/Saddle

Canadian Nightcrawler Underside, Showing Clitellum/Saddle

Can You Vermicompost With Canadian Nightcrawlers?

In short, not really. While you can keep Canadian nightcrawlers, and create a thriving population with which to use as bait, they are not great composting worms.

Canadian Nightcrawlers are anecic. This means they tend to make deep burrows, surfacing only to feed on decaying plant matter. They then retreat into their vertical burrows. Composting worms are generally epigenic, meaning they live in and around the surface of the soil, will use the same burrow occasionally, but will also travel around and explore the bin more often. Due to the behavior of epigenic worms, it is easier to feed them.

Vermicompost, called castings, will tend to gravitate towards the bottom of the bin. Fresh bedding and food can be added to the top, where epigenic worms will migrate to eat the decaying food.

Canadian Nightcrawler and Indian Blue Worm

Canadian Nightcrawler and Indian Blue Worm

Canadian Nightcrawlers are very large worms, with an obvious clitellum and flattened, spade-shaped tails. You can keep a population of Canadian nightcrawlers if you can keep them cool and ensure they stay moist, with lots of leaf litter. However, they do not make for great composters, due to their burrowing nature.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2021 Devin Gustus

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