A group of long-billed prairie birds migrates from a pristine, protected prairie to a nearby, newly restored prairie. They colonize and establish a breeding population in the restored prairie. Years later, scientists compare the two bird populations and find that long-billed prairie birds in the newly colonized area consume a much smaller range of food types than birds from the original population, even though food availability is similar in the two areas. What might be an explanation for this

While the long-billed prairie-bird’s fundamental niche included a wide range of prey species, competition with other species in the newly colonized prairie reduced the realized niche such that fewer food types were utilized

Explanation:

Options  are given:

The two populations of the long-billed prairie-birds had different fundamental niches, but the same realized niche

The original population of long-billed prairie-birds had higher levels of competition for food resources and in order to find enough food had a more varied diet. Those in the newly colonized area faced less competition and adapted to a smaller range of food types.

While the long-billed prairie-bird’s fundamental niche included a wide range of prey species, competition with other species in the newly colonized prairie reduced the realized niche such that fewer food types were utilized

The long-billed prairie-bird’s fundamental niche shifted as a result of competition with other species such that individuals in the newly colonized prairie foraged on a smaller variety of food types

Since in the question it is mentioned that scientists compare the populations with respect to the two bird and determined for the long billed prairie birds and the available of food is same in the two areas

This above situation represents the competitive exclusion concept. The species should be entered into the competitor in the case when there is a large number and the feeding should be started for survival

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.