What you heard is simply not true. I asked this question of them while there. They changed what animals are in what savanahs. The same amount are there. The savanah directly affected by construction has Zebras (one baby, 3 full grown), giraffes (3 or 4, cant recall), various birds, african cattle (3), ostriches (2).
I was just in a room overlooking that savanah and saw all those animals. Its unfortunate you changed your booking based on false information. There is also very little noise, with the door closed on that savanah we heard absolute none over 10 days, with the door open you could hear som between the hours of nine and 5 sometimes, but not often. I often read on the balcony looking at the animals.
Give me a moment, I'll post pictures.
I checked Allearsnet, and the change in the animals in the savannah takes effect in January, right before our trip. So, to the OP, your August trip should be just fine

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Here is the info I found:
MPORTANT SUNSET SAVANNA INFORMATION: May 1, 2008: After receiving a reader email about animals being removed from the AKL savannas, AllEars® talked with
DVC spokesperson Diane Hancock:
"As the development of Kidani Village continues at Disney's Animal Kingdom Villas, crews are preparing to complete the new savanna and acclimate the animals to their new habitat. To accommodate this important process, animals are not scheduled to be on Sunset Savanna from Jan. 15-April 15, 2009.
Members and Guests who reserve a savanna-view room during this time will be advised of this process, and confirmations for those bookings will include a notation to that affect. Approximately 30 days prior to arrival, the resort will determine, based on occupancy and booking date order, which Members will be assigned to a Sunset Savanna view room. Member Services will notify affected Members, who, after their stay, will receive a Vacation Point credit reflecting the difference between a savanna view and standard view. As a reminder, animals on the other savannas can be viewed from multiple public locations at the resort."
Also, at this time, DVC has not set an official opening date for the Kidani Village and therefore has not set a date for reservations.