A Tiny Feather Duster Worm in Lake Baikal - Observation of the Week, 2/25/19

Our Observation of the Week is this Manayunkia feather duster worm, seen in Russia by @septima15!

Home to over 20% (!) of all the world’s surface freshwater, Russia’s Lake Baikal is Earth’s largest freshwater lake (by volume) and home to thousands of plant and animal species, the vast majority of which are endemic to its waters and surroundings.

Olga Medvezhonkova (septima15) works at a research institute near the lake, where she hydrobiology researcher. What does that entail? “Most of the time I spend on the beaches or the shallow lake area for sampling bottom animals and then studying them under a microscope to determine the taxon and count the number” is how she describes it. “This is part of the science of hydrobiology!”

“I met the polychaetes during the processing of the sample from a depth of 4-5 m,” explains Olga, “and I decided to learn how to identify them to species, and for this I took pictures.” A wealth of biodiversity can be found in these samples, and she says “I [also] constantly find mollusks, oligochaetes, nemtodes, and others in the samples, but most of all I’m passionate about water bears (Tardigrades).” Check out some of her water bear photos here - hopefully she’ll add some more to iNat!

The worm photographed above is in the genus Manayunkia, which is a member of the Sabellidae, or feather duster worm family. These are polychaete worms, and polychaetes are commonly called “bristle worms” due the setae protruding from each segment of their bodies. Many move about freely, like this enormous Alitta brandti, but others like the feather duster worms create a tube in which they reside. Olga says that Manayunkia reach about 5-8 mm in length, and “at the front end there is a corolla of tentacles, with which they breathe. [The] worms live in tubules built from silt or sand particles. Manayunkia live on sandy and silty soils, stones, sponges [and] they feed on detritus. The fauna of polychaete of Baikal today includes only 3 species, conditionally considered to be endemic (http://irkipedia.ru/content/bespozvonochnye_baykala_polihety).” Nearly all polychaetes are marine, so these freshwater species are of definite interest.

Olga joined iNaturalist only recently but says it’s “a very useful idea for collecting information on the global distribution of species. And to me personally, it helps to identify species in the definition of which I’m not an expert...I am very, very glad that the Internet users liked the photo of the Manayunkia so much, and even more so if they became interested in the Baikal Polychaeta itself.”

- by Tony Iwane

- Amazingly, Lake Baikal has its own endemic seal species

- Like many tiny things, Manayunkia can have a large impact on its environment. For example, Manayunkia speciosa can harbor myxozoans that parasitize salmonid fish.  

- Here’s some video of a much larger feather duster worm. 

Posted by tiwane tiwane, February 26, 2019 05:43


Wow! This tiny wonder is pretty impressive, thanks for sharing it. I just learned a whole lot I wouldn't have otherwise known...Thanks! Anyone else think this looks like a tiny cthulhu monster?

Posted by mira_l_b over 2 years ago (Flag)

Wow, I'm so excited to see more observations from Lake Baikal, @septima15! I visited in 2004 with the Tahoe-Baikal Institute Summer Environmental Exchange, and have been to Bolshiye Koty where this was collected! I wish I'd taken so many more photographs during my time in the area, but I was only able to add a couple of observations from old photographs. Lake Baikal has such incredible endemism and I was thrilled to visit. @maryeford also participated in TBI SEE, but before I did. Are there any other TBI alumni who are active in the Baikal area?

The recent growth of user activity in Russia is wonderful to see. I'm tagging @apseregin from the rapidly growing Flora of Russia project and @milakalinina from Funga of Russia.

Posted by carrieseltzer over 2 years ago (Flag)

Thanks so much for a very interesting observation!

Posted by susanhewitt over 2 years ago (Flag)

Very interesting!

Posted by bluejay2007 over 2 years ago (Flag)

An incredible addition to iNat.

Posted by lonnyholmes over 2 years ago (Flag)

Thanks @carrieseltzer for the respond. Two days ago the 100 000th observation from Russia was uploaded (see https://www.inaturalist.org/projects/flora-of-russia/journal/21914-31-000-flora-of-russia-100-000 for details). Currently, 38,5% of observations from Russia are vascular plants, 25,2% are birds, 19,2% are insects, 7,9% are fungi and lichens. 14 months ago (mid-December 2017) there were only 5,000 observations from Russia.
The national-wide projects include:
I'd like to tag @alexeiebel, @birdchuvashia, @dryomys and @max_carabus for promoting of iNaturalist's projects in Russia.

Posted by apseregin over 2 years ago (Flag)

Wow, I would love to see some of the Mollusk species.

Posted by predomalpha over 2 years ago (Flag)

Me too!

Posted by susanhewitt over 2 years ago (Flag)

Hidrobiology is an exciting job and potentially promises constant discoveries. Tony Iwane's note is appreciated. Thank you to Olga Medvezhonkova for giving us a sample of the polychaetes that inhabit Lake Baikal. @tiwane @septima15

Posted by geomanuel over 2 years ago (Flag)

Wow! Very fascinating! I learned so much from this post! Way to go, Olga! Keep those observations coming!

Posted by erikamitchell over 2 years ago (Flag)

Amazing! :)

Posted by paleo over 2 years ago (Flag)

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