ORIGINAL: zrexpilot
I'm not sure it's limited to hotter months, I think an animal infected with worms or parasites is infected, they dont just magically go away when it gets cold.
I killed a doe during season , it was cold! she had worms inside her. she smelled rotten whenI opened her up. Just left her for the yotes.
the wolfes (or bott flies larva) are only in summer times or hot mo's.
the internal parisites in an animal (worms)are there until they die or someone add wormer to the water supply. the (bott flys are like the skitters;in winter there gone; pretty much) they don't produce the eggs in winter.
sorta like worms in the speckle trout in the gulf waters. they have a few all year.in the hotter summer mo's. July ;Aug.; Sept. they have a BUNCH.just nature. the worms have to eat also.

thats what the intomoligest training says anyway.
JMHO.