Nightcrawlers are a form of earthworm

Earthworm

Earthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...

. Prized primarily for use as fishing bait

Fishing bait

Fishing bait is any substance used to attract and catch fish, e.g. on the end of a fishing hook, or inside a fish trap. Traditionally, nightcrawlers, insects, and smaller bait fish have been used for this purpose...

, nightcrawlers are generally known as either Canadian or European

Canadian nightcrawlers are the larger of the two, measuring up to 14 inches (35.6 cm) when fully extended. Fishermen enjoy the Canadian worm

Worm

The term worm refers to an obsolete taxon used by Carolus Linnaeus and Jean-Baptiste Lamarck for all non-arthropod invertebrate animals, and stems from the Old English word wyrm. Currently it is used to describe many different distantly-related animals that typically have a long cylindrical...

 more because of its size. It can be easily secured to a fish hook

Fish hook

A fish hook is a device for catching fish either by impaling them in the mouth or, more rarely, by snagging the body of the fish. Fish hooks have been employed for centuries by fishermen to catch fresh and saltwater fish. In 2005, the fish hook was chosen by Forbes as one of the top twenty tools...

, and stays lively while submerged in water for up to 5 minutes. The Canadian nightcrawler is used for catching largemouth bass

Largemouth bass

The largemouth bass is a species of black bass in the sunfish family native to North America . It is also known as widemouth bass, bigmouth, black bass, bucketmouth, Potter's fish, Florida bass, Florida largemouth, green bass, green trout, linesides, Oswego bass, southern largemouth...

, smallmouth bass

Smallmouth bass

The smallmouth bass is a species of freshwater fish in the sunfish family of the order Perciformes. It is the type species of its genus...

, carp

Carp

Carp are various species of oily freshwater fish of the family Cyprinidae, a very large group of fish native to Europe and Asia. The cypriniformes are traditionally grouped with the Characiformes, Siluriformes and Gymnotiformes to create the superorder Ostariophysi, since these groups have certain...

, trout

Trout

Trout is the name for a number of species of freshwater and saltwater fish belonging to the Salmoninae subfamily of the family Salmonidae. Salmon belong to the same family as trout. Most salmon species spend almost all their lives in salt water...

, catfish

Catfish

Catfishes are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores...

, sunfish

Lepomis

Lepomis is a genus of freshwater fish in the sunfish family of order Perciformes. The most recognizable species of the sixteen in this genus is the Bluegill....

, walleye

Walleye

Walleye is a freshwater perciform fish native to most of Canada and to the northern United States. It is a North American close relative of the European pikeperch...

, and other freshwater fish. The Canadian nightcrawler will not survive in temperatures above about 65 °F (18.3 °C). Therefore, bait shops must keep them refrigerated and attention must be given to ensure that the worms are not left to rest in the hot sun while fishing

Fishing

Fishing is the activity of trying to catch wild fish. Fish are normally caught in the wild. Techniques for catching fish include hand gathering, spearing, netting, angling and trapping....

.

Harvesting

Canadian nightcrawlers are harvested in certain locations in North America. Most come from Canada's Ontario region, while many millions more are harvested along the Appalachian Mountains

Appalachian Mountains

The Appalachian Mountains #Whether the stressed vowel is or ,#Whether the "ch" is pronounced as a fricative or an affricate , and#Whether the final vowel is the monophthong or the diphthong .), often called the Appalachians, are a system of mountains in eastern North America. The Appalachians...

 - from western North Carolina

North Carolina

North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...

 up to New York

New York

New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...

. The worms are collected by headlamp-wearing hunters. The worms come out from the ground only at night (or when the ground is deeply saturated following a decent rain fall).

In popular culture

Nightcrawlers is an imagination-based game played by the characters Charlie and Frank on the television program It's Always Sunny in Philadelphia

It's Always Sunny in Philadelphia

It's Always Sunny in Philadelphia is an American television sitcom that premiered on FX on August 4, 2005. New episodes continue to air on FX, with reruns playing on Comedy Central, general broadcast syndication, and WGN America—the first-ever cable-to-cable syndication deal for a sitcom...

. The goal is to crawl around on the ground at night like worms. Charlie's rival, Schmitty, suggested that the game be enhanced by having 'bases.'

In Fargo

Fargo (film)

Fargo is a 1996 American dark comedy-crime film produced, directed and written by brothers Joel and Ethan Coen. It stars Frances McDormand as a pregnant police chief who investigates a series of homicides, William H...

, nightcrawlers are given to Norm Gunderson by his wife Marge.

In the 1995 Warner Bros.

Warner Bros.

Warner Bros. Entertainment, Inc., also known as Warner Bros. Pictures or simply Warner Bros. , is an American producer of film and television entertainment.One of the major film studios, it is a subsidiary of Time Warner, with its headquarters in Burbank,...

 movie, Grumpier Old Men

Grumpier Old Men

Grumpier Old Men is a 1995 romantic comedy film, and a sequel to the 1993 film Grumpy Old Men. The film stars Jack Lemmon, Walter Matthau, Ann-Margret, and Sophia Loren, with Burgess Meredith, Daryl Hannah, Kevin Pollak, Katie Sagona, Ann Morgan Guilbert...

, nightcrawlers and the gathering thereof are employed as a vehicle to facilitate the developing romantic relationship between Max Goldman (Walter Matthau

Walter Matthau

Walter Matthau was an American actor best known for his role as Oscar Madison in The Odd Couple and his frequent collaborations with Odd Couple star Jack Lemmon, as well as his role as Coach Buttermaker in the 1976 comedy The Bad News Bears...

) and Maria Sophia Coletta Ragetti (Sophia Loren

Sophia Loren

Sophia Loren, OMRI is an Italian actress.In 1962, Loren won the Academy Award for Best Actress for her role in Two Women, along with 21 awards, becoming the first actress to win an Academy Award for a non-English-speaking performance...

).