Wednesday, 7 May 2008

Baby Corys?

A while ago I tried to convince my pygmy corys to breed, but without much luck. Water changes (especially in coincidence with weather fronts) could get them to come out and "dance". Recently I have noticed more complex behaviour, including what looked a bit like the "classic-T" behaviour that spawning corys adopt. But I had pretty much given up hope of anything actually happening.

Last night I noticed something moving at the front of the tank. Before it darted back into the thicket of Hemianthis I saw something that looked like a tiny tadpole, maybe 4-5 mm long. It took me a moment to realise what I had seen - fry! Over the next couple hours I caught another glimpse of it. Very cool!

Now, I can't say for certain that it actually was a baby cory - there are also a few Otocinclus in the tank, but odds are that it was a pygmy cory. Pygmy corys are considered easy to breed, while Otos are rather less easy. Also both fish are easier to breed in groups - I had 7-10 corys in the tank, but only three Otos (and one, I suspect, is a different species from the other two).


While I have read some of the people at ScienceBlogs on a daily basis for months, I still have not plumbed the depths of what’s available in terms of good reading. I recently came across Shifting Baselines, a good ecology/conservation biology blog written by Jennifer Jacquet, a doctoral student at the University of British Columbia, Josh Donlan, a conservation scientist at Cornell and Randy Olson, the creator of A Flock of Dodos.

In January, Jacquet discussed a study which looked at replacing fishmeal (which is used to feed chickens, pigs and fish) with “bugmeal”. Working with striped bass, researchers at Mississippi State University found that the fish readily took the “bugmeal” and the final product was similar to fishmeal raised fish, but had a less “fishy” smell (which is considered a bonus by American consumers). Today she presented some response to questions she asked Lou D’Abramo, the lead scientist on the Mississippi State project.

The first question really gets to the heart of the problem of our industrial food production system: what are the insects raised on? The answer - grain, probably corn. Lovely. Fortunately, D’Abramo seems to be aware of the problem with that, and discussed the idea of raising them on fish wastes. He also talked about raising insects on waste products to alter their fatty acid profile - something that wouldn’t have have been the least bit surprising had I read that with my aquarist brain switched on…you read a lot about fatty acid profiles in the context of getting your Corydoras to breed. (I should do a less good job of compartmentalisation.)

Finding a substitute for fish meal is a good thing. Insects sound like a good substitute. But our industrial system of agriculture just makes things like this awfully complicated - needlessly complicated. Small farmers feeding fish on grubs or mealworms raised on locally generated waste sounds workable. Industrial-scale “bugmeal” production, on the other hand, raises the usual problems of energy demands, transport, and waste production. One step forward, but we’re on a conveyor belt running us backward…