"Larval fish" are the "tadpoles" of fishes. They are hatchlings that have
uncurled and become mobile and fishlike. They have a long, almost
continuous fold of skin around their bodies called the fin-fold from which
the dorsal, anal, and caudal fins develop. There are two (or three) main
stages: yolk-sac stage or prolarvae (when fish live off their own energy
reserves but begin to feed on their own) and postlarvae (when fish are
feeding, and when they have attained recognizable internal organs, rudiments
of fin rays etc.). Fish are no longer considered larvae when they have
attained their full fin-ray counts. After this is a stage is a phase some
people call pre-juvenile, when scales, fins, spines, and pigmentation
formation are completed - this is when fish are usually referred to as fry.
All fish pass through a larval stage of some sort (except livebearers?).
>>>What else is typically caught in a drift net? If the mesh is small
enough,
local wild daphnia?<<<
Aquatic insects, entomostraca.
>>>When you check a drift net, how do you do it? Empty everything in a
glass
jar and see what is there?<<<
Right. The net everts and you dump the material accumulated in the back of
the net into an enamel pan or jar.
>>>Could you jury-rig up something with say cheese
cloth? How big are they normally?
Probably but I do not think it would be worth the effort - usually 12-18 "
>>>Anyone have a picture or a good
description of the shape of one?<<<
check out Merritt and Cummins book - "An Introduction to Aquatic Insects of
North America"
or any biological supply catalog
>>>How deep are they set? Would you catch
anything in a stationary one in a lake or pond?<<<
usually in water < 1 m deep. Probably not - no way to keep net extended, no
impetus for animals to go into the net.
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