Can't say for sure with that description, but it certainly sounds like barn swallows.
If you go on build to survive the drakobloxxers tou can use the small purple brick. But put it on both legs and then if tou do it properly you wil be able to stqrt moving forward and up.
brick
brick layers
Some birds do not build nest's .why?
1 year-not done yet brick brick brick
Used to build houses
why do all birds build nest
Other Birds
Found a few good sites:http://www.readersdigest.com.au/handyman/how-to-build-a-brick-letterbox/article114102.htmlhttp://www.bluecirclesoutherncement.com.au/Docs/Howto/PackagedProducts/HP_HowTo_BrickLetterbox_pf.htmlhttp://www.renovateforum.com/f176/my-new-brick-letterbox-77979/
2500
brick
90