Spawning By Myself…

20 12 2012

Recap:  To bring more credibility to my project and determine how realistic my experimental design with surrogate particles is, I will release live gametes and measure the amount of fertilized eggs in a mesh container as a function of distance from live sperm, released from a fixed distance using an IV bag.  To learn how to spawn abalone, I participated in a pinto spawning up in Mukilteo several weeks ago.  I received 16 red abalone from the Cayucos Hatchery, and have been holding them for six weeks with the intention of further honing my spawning skills…

 

My red abalone (B. Blaud)

My red abalone (B. Blaud)

Spawning by myself sounds like something completely dirty, but I assure you, it’s not.  Since November 6th, I have been holding red abalone in the basement at the University of Washington with the intention of practicing the spawning protocol I learned with pinto abalone up in Mukilteo and honing the methods to something I can use in the field as part of my experimentBy the time I was ready to practice spawning them, I had 13 red abalone, 9 females and 4 males.  I was preparing to go to San Nicolas Island (SNI) for one of my experimental runs with surrogate particles, but wanted to have one solo spawning under my belt beforehand.

 

I headed down to the basement fairly early on the Friday morning to set up for the spawning experience.  The first steps are measuring up the participants, their gonads to be exact.  I measured the gamete index for each abalone, to identify which abalone was ripe, and separated them into buckets based on gender – boys in one bucket, girls in another.  Determining ripeness was a little more difficult than I anticipated, as none of my abalone were all that ready to spawn.  I looked under each of their skirts, but had a hard time identifying males from females in many cases.  It’s supposed to be fairly straightforward.  I hold the abalone, shell down in my right hand with the base of the swirl in the shell, their head near my fingertips and the apex in my palm.  After the abalone calms down for a second, I’m able to move the foot to the side to see the gonad at the base of the shell.  The gonad index identifies ripeness based on color and the amount of swelling in the gonad.  Yellowish-creamy white means male (makes sense – sperm is white), and a greenish-purple indicates female (the eggs come out an olive green).  An index of 0 is unripe, where the gonad is indistinguishable as either male or female; an index of 1 indicates when there is slight coloration and swelling of the gonad; an index of 2 has swelling of the gonad up to the mantle, the edge of the shell; and the highest index of 3 is visibly swelled over the edge of the shell, where you can see it with barely moving the foot to the side.  All of my abalone were at my un-expert opinion a gonad index of 0 or 1. 

 

Diagram of abalone gonad (Rogers-Bennett et al. 2004 J Shellf Res 23: 553).

Diagram of abalone gonad (Rogers-Bennett et al. 2004 J Shellf Res 23: 553).

I separated the abalone I rated as a gonad index of 1 into separate buckets, then put a couple abalone rated as 0 into their own buckets, since I couldn’t conclusively determine their gender, but wanted to spawn more than a handful of my abalone.  I added the appropriate amount of Tris(hydroxymethyl) aminomethane (or Tris, for short) and 6% hydrogen peroxide, covered them in a tarp to provide darkness (and a little privacy), and then left them alone with only short, periodic checks for spawners.  I mentioned before that these are all unripe abalone with a gonad index of 0 or 1, so it goes without saying that I wasn’t overly optimistic about the possibility of getting any of them to spawn.  So, imagine my surprise when I went down after only 90 minutes of them sitting in the dark to find one male and one female spawning in separate buckets!  I was so excited, I barely remembered that I was supposed to rinse them off and put them in a bucket of clean seawater (with no chemical additions), so they could finish spawning and have usable gametes.  As soon as that was done, I ran up a couple flights of stairs to find Glenn, who would share my astonishment and simple joy at these unripe, unready abalone suddenly releasing their gametes.

 

Hatched abalone larvae (http://www.lib.noaa.gov/)

Hatched abalone larvae (http://www.lib.noaa.gov/)

Eventually, after about 3 hours, all the red abalone had been rinsed and placed in buckets of clean seawater.  Due to the unripe nature of the abalone, they didn’t spawn a significant amount of gametes.  It was a great exercise going through the protocol, and learned a lot about what would work in the field, what needs to be modified, and ponder what it would be like to be an abalone parent, with millions of children, somewhere out there… but I’m weird.

 

After spawning my red abalone, a good practice run, I felt oddly optimistic about future experiments.  I should say, cautiously optimistic, because when you say the word “experiment,” I get an ominous chill and view of everything that could potentially go wrong.  I am starting to get more and more excited about the results that experiments with live gametes will yield.  But that, my faithful readers, is a story for another day.

 

And next, I will tell you all about Run 7, and my latest stay on the island…I can’t wait to go back!

Advertisements

Actions

Information

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s




%d bloggers like this: