In this thesis, I explored whether and how environmental clutter affects the process in which an animal searches for a goal. Previous research has suggested that to locate a goal, animals encode specific properties of landmarks. How uninformative objects, or clutter, in the search space impacts this landmark-based goal calculation needs further investigation. I examined this topic using rock pigeons (Columba livia) and pinyon jays (Gymnorhinus cyanocephalus), chosen for their pronounced spatial abilities. I hypothesized that these species would differ in their use of spatial information when learning the location of a goal, and that pigeons would be more affected than pinyon jays by modifications to landmark color and by the appearance or disappearance of environmental clutter. I trained the birds to find a goal using an array of four distinctively colored landmarks. For each species, I assigned birds to one of two groups. Whereas the search space for Group Open contained just the landmarks and the goal, the search space for Group Clutter also contained a set of uninformative objects to simulate environmental clutter. During training, the goal-landmark array rotated and moved across the search space, so that only the landmarks can inform the goal location. Following training, I tested the birds and measured their search error for each experimental manipulation. When learning about the goal location, rock pigeons interpolated the absolute and relative metrics from adjacent landmarks, in both environments. Moreover, pigeons in the cluttered environment used absolute metrics from single landmarks. Pinyon jays exclusively used the absolute metrics from single landmarks in both open and cluttered environments. When the distinctive color information was removed from the landmarks, pigeons but not pinyon jays searched with more error in both environments. For both species, adding clutter to the open environment increased search error, whereas removing clutter from the cluttered environment decreased search error. Findings from the present study suggest that rock pigeons and pinyon jays use different metrics to encode goal-landmark relations, pigeons are more affected by changing the landmarks’ color information than pinyon jays, and the abrupt change in environmental clutter impacts search error for both species.