This paper is about a threatened bird species endemic to Africa. It is a wetland dependent large waterbird. Although it is found in many countries, its population in Tanzania has declined sharply in recent years. This article is a review of what happened for such unexpected decline.The study was supported by The SIMMORS-Project, Mohamed bin Zayed Species Conservation Fund Project No. 0925790, Tampa's Lowry Park Zoo, and Seoul National University Environmental Leadership Program Alumni Scholarship.