My outdoor containers are mostly kept with raising daphnia in mind. I have
found that usually if the containers are kept under the trees (and in my
case strategically between a wood pile and berry patch to cut down on
tourist traffic) the dragon flies have almost never found them to lay eggs.
(Knock on wood....)
It was suggested to me that exposed water reflecting sunlight is visible at
quick a distance in the air. Some years back our exposed containers
certainly drew dragonfly and subsequent larvae, damselfly and their larvae,
a couple of species of water bug, water skaters, and backswimmers. We are
down wind from some marginal wet lands.
Under the trees the daphnia gets joined by blood worms, other cladocerans
(brought in by the wind? varmints' whiskers?) and the occasional glass worm.
If the daphnia population is maintained at a pretty high density, the vast
majority of mosquito larvae are evidentally consumed while microscopic and
few large larvae were found. (This last dry year for some reason was a
better year for glass worms. Maybe a lack of alternate sites)
Mossie egg rafts are useful floating in the tanks of small mouthed, surface
feeding fry and were skimmed off once in a while.
Rarely damsel fly larvae will infest a culture. They don't seem to take the
toll that dragonfly larvae take and are pretty well accepted by fish if the
damselflies are bite sized.
As an experiment last summer several smaller containers - the 20 gallon
plastic tubs (blue in our case) sold for $6 each at Menards - were placed
under the trees. Standard floating aquarium plants (water sprite, salvinia,
anacharis), water hyacinth and a little water lettuce were included in
different containers. Fish growth wasn't very impressive, indicating that
such small containers needed to be more often fed.
We actually added RO and rain water to the tubs so that birds, squirrels and
chipmunks could drink without falling in.
Despite a thinning of the tree leaves in the parched summer months, most of
the fish survived without noticeable predation.
I would be interested, from the standpoints of live food production and fish
raising, in what the experiences of others might have been raising aquatic
things in the shade as opposed to in the open sunlight.
Jeff's accounts of larger containers are intriguing. Maybe a move after
retirement would be to a larger parcel of land where projects such as that
are possible. Then will have to learn to keep sunfish. :)
Also ... know of killie nuts raising daphnia in stock tanks - then one needs
a freezer and bagging kit to save the daphnia. ;)
Jeff, do you have photos of your outdoor tubs and of your greenhouse on-line
Thanks and all the best,
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