Every year I get ASY males first, then the females show up along with a few subbies.
The very first year they came we had no house for them. I had 5 Martins. all adults, visiting daily. They kept coming to our yard sitting on the many power lines that cross my property & singing away. So we got them a house. They have returned every year since. We usually get 4-7 nesting pair each year. I think allot depends on the weather & the long trip back from the deep south as to how many we end up with. I know we lost a female one year to a broken leg. She hung in there & feed her chicks until they were ready to fledge then flew away & died. She'd crash land on the balcony with dragonflies & lay on her chest, hobble to the nest hole & feed her 3 chicks, then she'd rest & fly off for more dragonflies. The male ended up fledging the babies. That's dedication!
Our weather can do freaky things this time of year (like the snow 2 weeks ago & cold temps last week), so I tend to wait to put the house up. Also one year the sparrows took it over before the martins got here & we had to keep tossing them out. The neighbors had seeded their yard & spread it with straw. The sparrows packed a 5 gallon bucket full of their straw into our martin house daily!! Now I only get 2 pair of sparrows that share the house with the martins. The male we have here today is diving at the male sparrow. Tomorrow if he brings friends they will torment the daylights out of the sparrows. I've seen the martins actually sit in front of the sparrow nest hole & refuse to let them in to feed their babies until dark.
We also let the house up for a few weeks after all the babies fledge, as the parents keep bringing them back during the day. Once we no longer see them we take the house down & clean it & store it for winter. We also remove the tri-tel pole & store it for winter. We get too many wind storms over winter to risk letting it up to be damaged.
I just checked the house & the male is gone. It's almost dark, so he may have gone to the forest for the night. Tomorrow is another day

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Hey the humming birds will be here soon too

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Toy in PA