gardenlen writes:
more thinking of teh ingrediants which i will try this season, but
will still use my trap bottles so once in they can't get out and
usually drown anyway, just that the femal tropical fruit fly is very
hard to lure we run male fruit fly wicks in trap bottles not made to
hold the fly in in but to protect the wick from weather once in the
bottle they succumb to the pheramone small and land on the wick or
breathe the fumes and die.

Ah! I misunderstood you. I associate you with homemade lures and traps, so
when you said you were trapping mostly males, I pictured your vegemite +
sugar, etc., lure to be attracting a few females but lots of males. I see now
that you are using separate traps. (Though I wonder whether you couldn't
combine them, with the wick placed in the neck of the jar well above the
liquid lure? Especially if you could arrange for the females to not drown
or die, this would allow their natural pheromones to continue beckoning
in hordes of males.)

Anyway, by coincidence, on Don Burke's radio gardening program today
an expert was discussing fruit-fly traps. He said that as soon as females
emerge they head for a source of protein as this is required to get their
eggs developing. Once they have fed, their mission then becomes to find
a male and after that a suitable fruit to deposit their eggs. He said that
you have to catch them as soon as they hatch and before they get that
first protein feed otherwise they are not interested in your lure. From
this I would conclude that you'd need to have your female lures set right
from the word go, so they stand a good chance of intercepting those early
hungry virgin females.

The expert on the radio didn't explain exactly what sources of protein the
females would typically seek out, but I know yeast is a source of protein,
whereas sugar is not. The trap he was talking about was Eeco Natura Lure.

I recall reporting here some years ago on an article I'd read, where the
finding was that fruit-flies are strongly attracted to certain colours.
This varied with the species, but I recall bright purple being a strong
attraction for one species. (I'd guess they were talking about female
flies, with the idea being to have hanging around your garden lots of
sticky objects of the fly's preferred colour. That sticky fly paper that
you can hang from the ceiling could be a source of sticky stuff to put
near a bright purple plastic bottle. Or you could put your vegemite lure
inside a purple plastic bottle to give it an even stronger allure.

If, despite high levels of fly infestation, you are managing to trap few
females, perhaps they are hatching earlier than you allow for, or perhaps
the protein source or the Winter refuge for the flies is in a new location
where they are now hatching nearer to a source of protein than to your
traps? Thus they never pass by your lure, at least, not until they have
mated and are scoping out your back garden for some fruit in which to
deposit their eggs. It does seem counter-intuitive, but instead of
hanging female traps all around your own garden, maybe you need to
search for that person in the neighbourhood who is allowing fallen fruit
to rot on the ground and ask may you hang a few hundred female traps
throughout their backyard instead of yours during Spring and Summer?!

Good luck with your Spring trapping! Maybe there's a market for the pelts?

BTW, do you still have your eco-friendly "enviro throne" there Len?
--
John Savage (my news address is not valid for email)