The Basics of Blood Worms

Not to be confused with the leech, which is a carnivorous or bloodsucking worm, the bloodworm is the larvae of the midge and it feeds on algae and detritus. Blood worms are red because their blood plasma contains haemoglobin, like human blood. Also spelled “hemoglobin,” haemoglobin increases its ability to take up oxygen. The larvae commonly burrow in the oxygen-poor mud bottom of pools and rivers, so haemoglobin is of great value to the larvae.

Blood worms are quite long, and they have a distinct head. Segmentation is pronounced on the abdomen. Prolegs or “leg like” projections are found on the first thoracic and last abdominal segments of the bloodworm. On the last abdominal segment, are the gills. On some blood worms, gills can also be found on the segment preceding the last segment. They have an average length of 6 mm/0.2 inches in length.

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Blood worms have a special talent. They frequently build tubes of mud around themselves. The tubes may be may be attached to stones. Because blood worms are a favorite for fish, fishermen commonly use them for bait.

While the most recognizable physical characteristic of the bloodworm is its red color, not all midge larvae are red. Some are green and others may have blue bands. Green blood worms get their color from their environment. They typically frequent surface waters.

Where to Buy Blood worms

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Frozen blood worms can be purchased through a number of online as well as freeze-dried. Simply search “buy blood worms” for results. They can also be purchased from just about any bait and tackle store. It is important to keep in mind that once defrosted, blood worms can accumulate bacteria. This can also happen if you thaw them, then refreeze them. This can be dangerous if you plan to feed them to your tropical fish.

1 Comment

  1. Rebecca Lee

    We use bloodworms for bait while ice fishing on the Kennebec river in Maine. They are always at least 5 inches in length and often come 15 or more inches long with more “legs” than one can count. They can bite with their mouth that contains retractable “fangs” that look similar to snake fangs but instead move straight forward out or back into their mouth.

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