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Bamboo Worms Polycheate Worm Reproductive Phenomenon Nereis virens (Polychaeta) Clam worms? Worm feeding Mysterious calcified clusters

Bamboo Worms - Received from Silva in Ucluelet, B.C.

Q: Thanks for answering my limpet question! Here's another one: about marine worms. Every few months there is a huge drift of what I think are worm tubes washed up on Long Beach. The tubes are empty, translucent, segmented, and only a few millimetres in diameter. Locally they are called "bamboo worms" What I'm curious about is: are they worm tubes? If yes, why do they wash up in huge drifts every few months? Are the worms shedding their tubes or do they die off?

A: Yes, what you found on the beach are Spiochaetopterus costarum (commonly known as the Bamboo worm) tubes. Bamboo worms are members of a family of polychaete worms called Chaetopteridae and are found in rocky subtidal habitats. All chaetopterids have translucent tubes and usually occur in large aggregations. Spiochaetopterus costarum is distinctive because of its segmented tube. Since tubes of bamboo worms are found on the surface of the substratum, any disturbance, especially storms, can easily dislodge pieces of the tube or the entire tube. The tubes you see washed up on the beach are not shed by the worms, but the empty tubes do not indicate a dead worm either. Often when there is a disturbance, bamboo worms will contract so that their bodies are located near the bottom of the tube, leaving the empty top part of the tube to be broken off and washed away, or eaten by a predator. They can build new tubes if their old one is damaged. It should be noted that the common name of "bamboo worm" is often applied to members of the family Maldanidae, which are actually quite different from chaetopterids. These have tubes with thick walls made of mud and fine sand grains, and are not translucent and thin-walled like those of chaetopterids.

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Polycheate Worm Reproductive Phenomenon - Received from Robert Lewis in Winnipeg

Q: My name is Rob Lewis and I'm a second year bio major at the University of Winnipeg. I (and three other universities) are having trouble identifying an animal. One of my professors said that you folks would be the people to ask. I'm not sure if I'm emailing the right person about this but I'm sure you could let me know who to deal with at the station.
Well, here's the situation, a friend of mine is a professional underwater cinematographer. He was filming during a night dive somewhere in central America(I don't excactly recall where) when out of the darkness came these thin, roughly fifteen foot worms. The worms swam in a cork-screw fashion towards the divers. When they got to close to the light they literally exploded into a green silty substance. Any pieces of the initial organism still intact continued to swim about. Ian (my friend) managed to attain about five minutes of high quality footage of the animals.
In the past three years Ian has been trying to identify these creatures without any luck. If you or any of your colleagues would be interested in trying to identify the animals I would be more than happy to mail a copy of the tape to you. Please let me know. Thanks.

A. Most likely, the event that your friend Ian observed and filmed was a reproductive frenzy of polychaete worms. We have a related phenomenon here on the BC coast each summer. A few species of polychaetes belonging to the genus Nereis will swarm on certain summer nights. Both males and females swim near the surface and their segments break up dispersing gametes that will fertilize and develop as plankton in the sea. The spawning of Nereis pelagica is especially spectucular, as they can form swarms of thousands of worms. Nereis brandti also spawns at the surface, and they are so big (up to approximately 3 cm in diameter and 60 cm long) that they look like a mink swimming in the water from a distance.

Your observed event probably involved sexually mature worms of both sexes swarming (they generally are attracted toward the moon, -- your friend's dive lights probably substituted for that). The posterior portion of each worm was probably an "epitoke", a gamete-filled sequence of segments, that suddenly breaks apart releasing the gametes in the thick of the frenzy of worms. The anterior portion of the animal probably then swam offto return to the coral reef.

In the South Pacific there is a similar event where "Palolo" worms swarm precisely on the 7th night after the first full moon following the autumnal equinox. The Palolo worms are reported to be 40cm or more, and they are actually only the epitoke portion (the head end remains down in the coral reef). You might check the textbook by Pears, Pearse, Buchsbaum, and Buchsbaum LIVING INVERTEBRATES, 1987 edition or later. On page 413 and 414 of this edition, there are pictures of the worms.

Answered by David Denning, BioMedia Associate and Tara Macdonald, polychaetologist.

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Nereis virens (Polychaeta) - Received from Tyler in Lake George, New York.

Q: I am currently doing some research on Nereis virens with the assistance of Dr. Carl Merrill and Dr. Tom Trott, both with Suffolk University. I am attempting to determine what particle size in the substrate will be most advantageous to worm growth and health in mariculture. If you could give me any info or links to info on this polychaete it would be greatly appreciated.

A: Nereis virens inhabits muddy sand areas of the littoral and sublittoral zones in both marine and estuarine habitats. This species is found throughout the temperate regions of the northern hemisphere. N. virens lives in both sandy and gravelly sediment types, and has been kept experimentally in sand sediment sieved between 500 and 1000 mm using Endecott sieves and then washed with running sea water. This species does not appear to do well in muddy sediment, at least under laboratory conditions.

References:

Bass, N.R. and A.E. Brafield. 1972. The life-cycle of the polychaete Nereis virens. Journal of the Marine Biological Association of the U.K. 52: 701-726.

McLeese, D.W., C.D. Metcalfe and D.S. Pezzack. 1980. Uptake of PCBs from sediment by Nereis virens and Crangon septemspinosa. Archives of Environmental Contamination and Toxicology. 9: 507-518.

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Clam worms? - Received from Jessica in Duncan, B.C.

Q. : what is a clam worm? could you please tell me what it is. Thanks
Jessica

A:This was a tough one! It points out the difficulty that we can sometimes have with so-called "common names" for animals and plants. A common name in one area may not be the same anywhere else! In this case, the name "Clam Worm" does not appear in any of our local field guides to marine animals, and nobody that we contacted could say for sure what it might be, but we do have a couple of guesses.

You might be talking about the Shipworm, Bankia setacea.. This animal is not really a worm at all, but is actually a related to a clam! (so perhaps some people might call it a "clamworm") It burrows through wood by rocking its rough shells and carving out a smooth channel. A piece of wood that has been floating at sea for a long time may sometimes contain the burrows from these animals, and sometimes live animals inside. The burrows are about the thickness of a pencil, and have material inside that looks like it was made out of clamshell.

Another possibility for your mystery animal might be the worm, Nereis vexillosa. This is a large worm, up to 15 cm in length, and can be bluish or greenish in colour. It is often seen in quiet bays, especially at night, as it is attracted to the lights around docks. It burrows into muddy and sandy areas, often around mussel beds and in areas where there are likely to be clams. These worms may be referred to as "clam worms" by some people.

A common name for an animal is essentially a name that has been made up without regard for accuracy or duplication. A "scientific name" is a two part name that has been agreed upon by scientists all over the world. Only one animal in the whole world can have this two part name, which enables scientists from all over the place, who may speak different languages, to communicate with each other. It helps to avoid confusion! A scientific name is written in Latin, and is printed in italics - genus first, then species. For example, your genus and species is Homo sapiens.

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Worm feeding - Received from Emily in Indiana.

Q: How are earthworms and amphitrites alike regarding what they eat but very different in how they obtain their food? Why have the amphitrite evolved its particular way of getting food?

A: This is quite an interesting question, and needs some background first for those who may be unfamiliar with the genus of worms known as Amphitrite. The common earthworm (for example, the genus Lumbricus) and the worms in the genus Amphitrite are both in the Phylum Annelida (segmented worms). However, they are in different classes - earthworms are in the class Oligochaeta, while Amphitrite are in the class Polychaeta. To put this in perspective, they are as distantly related as a bird is to a mammal.

Both of these worms are deposit feeders. They take sediment or dirt into their mouths, and digest the organic material found in this sediment. Where they differ is in where they live, and how they obtain the sediment to eat.
Amphitrite are in the family Terebellidae, and live in soft sediment on the ocean floor. They are selective deposit feeders. Special head stuctures extend over the ocean substrate, and move back and forth. Deposit material sticks onto mucous found on these structures, and is conveyed back to the mouth where it is eaten. The worm does not have to leave it's burrow to feed. Earthworms crawl through the soil, eating sediments or dirt directly. The pharynx acts like a pump, drawing material into the mouth.

We are not aware of any speculation as to why the Terebellid worms have evolved the selective deposit method of obtaining food. It is possible that on the ocean floor, organic debris is located primarily on the surface, so these worms concentrate their food gathering activity only on the top layer of the substrate.

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Mysterious calcified clusters - Recieved from Greg in Malvern, PA

Q: When diving on a wreck in the bay behind Atlantic City, New Jersey, the sunken ship was covered with calciferous clusters of small white tubules (~0.2 - 2.0 mm dia and 1 - 10 cm in length). What are these stuctures? Are these the exoskeleton of Teredo navalis ?

A: Teredo navalis is actually a mollusc specialized for boring into wood. Although they line their borrows with calcium carbonate (it's not really an exoskeleton), these linings are in the wood, and usually flake off when the animal dies and the borrow is exposed to sea water. If the ship's hull was metal, it definitely wasn't T. navalis. What you are seeing is likely the result of tube-dwelling worms which excrete a tough calcified tube for protection. There are many different types out there. I suggest you look up a local intertidal field guide at a library or bookstore to see exactly which species it is.

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