Are you in the Pacific Northwest? Codling moths are flying here now, just started, but the apple maggot fly is still weeks (to a month?) away....so I am not sure you really meant to say apple maggot flies. The drosophilia fly, on the other hand, will be flying, but my understanding is they are currently not a problem....but when they become a problem, they will first go for the blueberries and strawberries and won't hit most fruits until maybe near ripening time.....and probably not the pears at all.... Anyway, the wet and humid Pacific Northwest is worried about this new fly in western Washington to enter onto the scene, but Eastern Washington and most parts of the country probably doesn't have to worry....I think. California has also been concerned. I welcome corrections if I am giving misinformation. I have heard of different traps, but it seems to me that white vinegar is often one ingredient used in some of the traps. http://www.ipm.ucdavis.edu/EXOTIC/drosophila.html

Personally I have had the most success with this sort of trap: The key is knowing how to properly use the traps. If I can find a good hole I get them 1st try about 90% of the time. This is a good informative video on how to do it properly: http://www.youtube.com/watch?v=Epe4DXA1yow We have such sandy soil here that I dont put the plug back on top of the hole, I use a small piece of plywood that is about 18" square and toss it on top and put dirt around the edges so that no light gets in. When I check the next day, normally the trail of ants is a dead give away that I got my gopher. I lay 2 traps 1 facing in each direction in the hole, have never used the peanut butter but it may be worth a shot. To be proactive against the gophers, I take the casualties and toss them on top of a 6' tall post that has a platform on top and usually that day, or sometime in the evening a hawk or owl will come by and eat them. I figure by feeding the prey animals they will be more likely to be in my area and they can do the job for me! Another technique I used to do is to take the dead gopher and push him into the hole I just caught him in and then fill the rest of the hole in. That way when he decomposes the stink passes through the rest of the passages hopefully sending a message to fellow gophers that this is not a safe area. My uncle has 300 acres and the gophers squirrels and moles get in and undermine graded banks etc, he ended up resorting to this: http://www.youtube.com/watch?v=DeywW7r4LA4 Must say its one of the funnest gopher traps I have ever used!

The baits like Sluggo with iron phosphate are safe for pets, and quite effective. Renais

When I had a severe fruit fly problem I put a small jar on top of my bin with a 50/50 mixture of water & white vinegar plus a couple drops of Dawn detergent and I literally caught hundreds within a couple days. But the traps are only a short-term solution. You have to have a properly designed bin system with most vent holes covered with fine mesh. Also, bury all fresh scraps well underneath the old stuff. Also, each time you add new material, cover the entire top surface with a layer of soil, shredded paper, or a solid layer of newspaper. Also, empty the tea regularly.