"Attack of the Giant Vultures" is a short film that appeared on Nickelodeon's "Short Films by Short People" series; a show that showcased short films made by kids. It aired a few times in the late 90s-early 2000s, but has never shown up online.
The cooked vulture, as seen in the promo video
The short involes a giant vulture chasing a pair of kids, culminating with them cooking and eating the bird. Some report that this short was particularly frightening for them as children.
The only footage available online are a few snippets seen in a promo video found on YouTube. I have personally emailed 2 of the 3 creators, (one of whom has confirmed that she doesn't have a copy, and one of whom hasn't replied) and Fred Seibert, (who produced the Nicktoons Film Festival, for which the short was originally produced) who sadly, does not have a copy either. Currently awaiting a reply from the 2nd creator...
The vulture can be seen at 0:10 and 0:19 in this promo video.