Winter 2009 Newsletter

The calendar may say it’s still winter around here, but love is in the air for some of our fishes! Several of the earliest spawners are busily going about the business of making little ones.

For the first time, we are working with sculpins! These fish came from the South Fork Holston River in Virginia. That makes for a fun time assigning species names with confidence (to living ones at any rate). Three species of Cottus could be present there, and the differences are subtle. Probably, the larger ones spawning right now are Cottus carolinae. Normally, knowing exactly what we are working with is a much greater issue. Not necessarily so in this case. These guys are going to be used as host fish for mussel propagation and any of these fish that might end up back in the wild would be returning to their place of origin. So, that aside, we do have a number of them spawning! The one tank where we have made most of our observations (almost certainly C. carolinae) has four females and one male. It appears that he has spawned with all of the females….one at a time. The clutches of eggs are separate, but in very close proximity to one another. We have chosen to leave this male in the tank with his nests and we also left the females to see what would happen. He is vigilant, but not terribly aggressive. He dutifully fans the eggs, mostly with his anal and caudal fins. The females pay little or no attention to him or the eggs once they have spawned.

We also removed a nest from another tank to make developmental observations. During all of this, our hatchery water temperatures have ranged from mid-40s F to mid 50s F. That’s pretty chilly water to be spawning in! Egg development has been extremely slow. The first spawns were noticed on January 28th. At the time of this writing (February 18th) none of the eggs have yet hatched! For the nest we removed, it took more than two weeks for the eggs to begin to develop eyes. They all sat for nearly two weeks with little or no signs of development at all. This makes us wonder if this is a response to the colder water. Water temperatures affect development times in all fish we have worked with, but it was as if these eggs experienced something like delayed development. We should hopefully know more about this with some of the later spawns.

If we are successful with these, they may prove to be a better option than wild collected fish currently being used as hosts.

Our slackwater darters, Etheostoma boschungi, from various wild populations are now spawning. What beautiful fish! I’ll throw in a picture just because! This is a propagated fish pictured here from the Middle Cypress Creek population.

Another first time fish for us is the rush darter, E. phytophilum. These began spawning last week. We have collected eggs and are incubating these as I write this. We have had good success with a close relative, the goldstripe darter (E. parvipinne).

We also have ashy darters, E. cinereum, spawning. We had limited success with these last year, but this year we have two very robust pairs and they seem to be producing viable eggs at this point.
This is one we will have to update you on in a later newsletter!

Aside from all of this we have been our usually busy selves! Thanks to a generous donation by one of our individual supporters, we have been able to have a 12’ x 12’ storage building installed on our deck. Having this will allow us to move much of our dry equipment out there….wetsuits, nets, masks etc. This will free up enough room to install three more racks to help expand our propagation efforts. Then we’ll have to expand outdoors and/or build a new building, because the back room will be full!

Finally, we now have more of our staff t-shirts in stock. This batch is a pale green (bamboo is what the shirt company calls them!). As with the others, these are 100% cotton and wear very well! One can be yours for a contribution of $25! We also have a new way of contributing. On our home page, there’s a blue button that says “Donate Now”. This will take you to a site called Change.org, specifically to the CFI page of Change.org. If you make a donation here of $25 or more, just be sure to fill in what size shirt you’d like and where to mail it to in the “Comments” section. If you prefer to donate through PayPal, the link above this button will take you there! We try to make this easy and painless. These donations really help us with the purchase of everyday items we need around here. Things that help us keep this work going! We really appreciate it!