I have a large multi-species African savanna habitat with multiple keepers assigned. Many of the food enrichment isn't being filled. For example: the giraffe feeder and forage enrichment have never been filled. While the fruit pole and the forage box (for ostrich and warthog) regularly are filled. The filled and unfilled are near eachother. The keepers pile food near the enrichment. Food grade 3. Land is flat and navigable. Any ideas? More keepers?