cactusflower

Donut blob that stumped the experts …

The Question: A friend found an egg sack shaped like a donut in Millinocket Lake in central Maine, and we are wondering what laid the eggs. The photo was taken with an underwater camera. The egg sack was in a little more than a meter (4 feet) of water and the blob was about 8 cm (3 inches) in diameter total.  The bottom is sandy with some silt sediments.  Nearby are lily pads, and a few grassy weeds, but otherwise, not much of anything else.

Submitted by: Pamela and Lori-Ann, Maine, USA

The Short Answer: This one has me stumped. I sent the photo to an expert on amphibian eggs who insisted it wasn’t anything he’d seen before. I sent it to an expert on bryozoans, the “blob under my dock” that is one of the most common questions for AskaNaturalist.com. The answer was negative. I sent it to an expert on freshwater snails, who nixed that possibility. It has been viewed by at least half a dozen biologists who work with fresh water lakes in Maine all the time. None of them could identify it. So you’ve stumped the experts.

My guess is that it’s some kind of anomaly – a normal object rendered abnormal by strange coincidence. For example, maybe it’s a salamander egg mass that happened to get curled around into a donut shape, and then stayed intact after the eggs hatched and the tadpoles dispersed. Or maybe it’s an Ophrydium blob that formed a donut shape. If you look at the third picture on this page, http://www.bio.umass.edu/biology/conn.river/ophrydiu.html, there is an Ophrydium blob in a roughly similar donut shape. Due to its symbiotic algae, Ophrydium would normally be green, but maybe this one somehow lost its algae so that it appears to be clear. One biologist suggested a shed snake skin that just happened to form a donut shape.

We’re grasping at straws here, maybe. So instead of a good answer, I can only offer two things:

1. If you ever see anything like this in Millinocket Lake again, please take more pictures and send them along and I’ll take another shot at it.

2. If any AskaNaturalist.com reader has an idea about what this is, please add it as a comment to the end of this article. If your suggestion is a good one, I’ll see if I can get an expert confirmation.

Thanks to Pamela and Lori-Ann for the question. Sorry I don’t have a better answer.

Share:
  • Digg
  • Facebook
  • Twitter
  • Google Bookmarks
  • RSS
  • del.icio.us
  • Reddit
Print Friendly Print Friendly

3 Responses

  1. Lori-Ann Willey Says:

    Tom,

    Thank you for your attempts. This one still has me curious, and all the more eager to get back into the lake and snorkel, but now that winter is upon us, it’ll be a while for sure though if possible, I break the ice and get underwater shots even during the winter months…always curious. I snorkel the shallow waters throughout the lake and will definitely be on the look out for such a thing as this in the future.

    Again, thank you for all your help.

    Always curious of nature! I can’t get enough of it, esp. the underwater world!

    Merry Christmas!

    Lori-Ann Willey

  2. Pamela Says:

    Once again, Maine baffles the Nation (smiles). Would it possibly be fresh water jelly fish? One year in Plymouth, Maine there were jelly fish found in Round Pond. It was the talk of the town!

  3. Tom Says:

    Pamela,

    I don’t think it could be fresh water jellyfish (Craspedacusta). They are considerably smaller than this. And they aren’t really donut shaped.

    I wrote something about freshwater jellyfish here: http://askanaturalist.com/is-it-safe-to-swim-with-freshwater-jellyfish/

    And some time ago, on an earlier website, I wrote something more extensive on freshwater jellies:

    http://curiousnature.org/A1-Jellyfish.htm

Leave a Reply

Your email address will not be published. Required fields are marked *

Please note: Comment moderation is enabled, so your comment may not show up immediately. Also, it's possible for your comment to be blocked incorrectly by the spam blocker. If you don't see your comment within a day or so, please use the Contact link in the menu above.

310,628 Spambots Blocked by Simple Comments

HTML tags are not allowed.