Birding around Caracas

There seem to be a migration route for boreal migrants especially raptors, swallows and swifts passing by Sabaneta, Mun. El Hatillo, Miranda state just half an hour out of the city of Caracas. I have been observing migration movements in Sept-Oct-Nov for quite some years and comparing with other sites around Caracas I have noticed a significant difference. Sabaneta lies along a ridge connected to more mountainous regions to the west and could be the easternmost outpost of the central coastal mountain-range for birds migrating along the coastal mountains. Migrants taking an easterly route after coming down through central america, passing Colombia and then hitting the Venezuelan Andes, might be the origin of these migrants but why are there so few turkey vultures if that is the case and so many swallows compared to other sites along the coastal mountain-range ? And where do these Broad-winged Hawks, Swainson´s Hawks, Barn Swallows, Bank Swallows, Cliff Swallows, Purple Martins, Ashy-tailed Swifts etc. end up after leaving leaving Sabaneta ? Guatopo N.P.? If so, and after Guatopo ?