Fudge got back to me with some info. Below find the text of his reply, and my email to him. I stand vindicated on my statement that the content of concentrate content had to be an order of magnitude less than someone’s estimate of 2 to 5% concentrate. I was wrong on my comparison to slug slime.
there aren’t any good numbers published in the literature (yet) on the percentages of water, fibres, and mucus protein in naturally formed hagfish slime. some preliminary experiments that i’ve done suggest that the slime concentrate swells several hundred fold in volume when it hits seawater, and a typical hagfish has about 3% of its body weight on board as slime concentrate. that means a hag can quite easily produce a mass of slime that is many times the volume of its own body.
as for what happens to the slime, if left undisturbed in a large volume of water, the mucus part of the slime will eventually dissolve away, leaving nothing but a wispy 3-D web of fibers. if the slime is disturbed, then the fibres tend to coalesce and trap the mucus, forming a mat of fibres and mucus. eventually, though, the mucus will disperse and the fibers presumably are broken down by bacteria.
slug slime is very different from hagfish slime in that it is more concentrated, cohesive, and insoluble.
i hope this helps, and sorry for the long reply time. i’ve been away for several weeks.
-------- REPLY, Original message follows --------
Date: Saturday, 06-Jan-01 07:09 AM
To: Doug Fudge \ Internet: (email@example.com)
Subject: hagfish slime questions
I got into a discussion of hagfish slime recently (odd thing, I know). Since I first saw a (less than 1 pound) hagfish turn a five gallon bucket of seawater into slime, I have wondered how the dickens they are able to do that. Seems like a huge drain on resources to me. If five gallons of seawater weighs about 44 pounds, and the proteins in the snot made up only one percent by weight of the resultant slime, the fish would be giving up 7 oz of protein (impossible, obviously, for a one pound fish) so the actual percentage of ingredients must be much lower. How much protein (and other important ingredients) does it take to make a given volume or weight of slime? How much slime can be produced by a single fish? Does this slime continue to grow and eventually dilute itself to nothingness, or does it reach a given size blob and stay at that size until it decomposes? I’ve seen pictures of hagfish traps with what looked like multiple ten foot long strings of slime hanging off them. Impressive, if you are into that sort of thing. I was interested in your description of the strings within the mucus. I made the guess (in mydiscussion/argument that precipitated this email) that terrestrial gastropods which use lots of slime probably used chemistry similar to that hagfish in order to produce the stuff efficiently. That supposition now seems largely in danger. Thanks for any light you are able to shine on this topic.