http://ksmrsm.blogspot.com/?zx=3f40fba6993e0ff3
Teaching out here in the bush has created countless experiences that I could not have had anywhere else. That, of course, is part of what has kept us out here this long. The experiences. And this is another one that is going to be pretty cool... This year, the opportunity came up to acquire the equipment to rear salmon eggs in the classroom...and - of course - I jumped at it. Those of you who have known me any significant amount of time knew how that was going to turn out without me telling you... At any rate, I attended an inservice in Fairbanks in October, and returned with a bunch of equipment, the rest of which would follow later in November before we were supposed to get the eggs. The funny thing is, I thought about how this WOULD HAVE BEEN the first year in a long.......long time that I haven't done any work with salmon, seeing as we didn't go to Orzinski last summer - worked with trout and catfish and sturgeon instead :). But that has now changed, and 2012 is no longer aquaculture free. :)
The project was very highly anticipated by the students. A week or so prior, I began working with the students on learning about rearing salmon in both Math AND Science class, and the enthusiasm that was met with was quite encouraging.
So, well ahead of time, Sarah and I got the tank and all the necessary equipment set up and running to let it operate a bit in advance. A pretty simple recirc system, the setup would be fairy easy and operation/maintenance would also be relatively light in intensity, thanks to such perks as a UV light, and brand-new cooling system with digital temp control, etc. Here are some pics of the riggin'......
The tank is covered in insulation foam to help keep in the cold temps required, as well as keeping out excessive light during the eggs and alevins' sensitive periods:
The system requires a chiller....(notice temp shown in this pic is Fahrenheit and is before operation)
as well as a canister, three-tiered filter system.......
Here is a shot of the two together:
The mess of hoses you see are transporting water from the tank into the filter, and then into the chiller unit, and then back up and into the tank, now at a balmy 5 degrees Celsius (41 Fahrenheit). The vertical intake nozzle that removes water is in the back corner of the tank, and the outflow from the chiller leads to the spreader bar all across the front of the tank, where the treated, chilled water dumps in. This creates a kind of reverse-upwelling water flow over the eggs.
The intake nozzle is covered with a sponge, so as to keep adventurous alevins and fry from getting sucked up into the filter...
Add some appropriately-sized gravel, and some water that's not loaded with fish killing agents or minerals, and away you go. :)
The eggs were scheduled to arrive last week (week of Thanksgiving) from the Ft. Richardson hatchery, and their arrival was so highly anticipated that there were about 20 students there on Tuesday to watch the action, even though it was after school hours.
The eggs came wrapped in a muslin (no, not 'muslim') cloth that was soaked in water, and that was wrapped in wet newspaper and surrounded by bags of ice.
After the ooohs and aaaahs, we placed the eggs in a mesh basket, and set them in place. A square was cut in the foam on the front of the tank in the appropriate spot so we have a removable viewing window right in front of the mesh basket, but do not have to expose the eggs to any extra light.
Though we'll have to try again this holiday weekend, Sarah took some pics of the eyed eggs so we could get a better look at the embryos inside:
There are pics still to add on this post***as of 11/23
Again, there will be many more posts, background info, and updates on the salmon project at the following website - another blog where my classes are working along with those at another school, St Mary's, from further downriver. Check it out!
http://ksmrsm.blogspot.com/?zx=3f40fba6993e0ff3
No comments:
Post a Comment