Premise: Hundreds of sea gulls scavenge for food as bulldozers bury rubbish at the now-closed Wake County Landfill in North Raleigh in this file photo. A study by Duke University researchers concludes that gulls feeding on trash can be a significant course of nitrogen and phosphorus at nearby lakes. TRAVIS LONG TRAVIS LONG
Hypothesis: The site in North Raleigh, which was used to fill trash is no longer used as there were  gulls which were feeding on the waste and it may the reason of  an increase in the level of phosphorous as well as nitrogen at water bodies closer to the landfill.