Rehabilitation studies and recovery of a once lifeless estuary: the Golden Horn

Abstract

Within this study fluctuations in biodiversity of the Golden Horn from past to present are evaluated. Limited studies and observations dating back to 60 years ago pointed out the importance of the Golden Horn as a fishery. Unfortunately, in accordance with increase in unplanned settlements and industry around the Golden Horn in the 1960s, pollution stress became a demanding factor for this unique environment, affecting biodiversity adversely. Preliminary studies in the 1990s indicated survival of only a couple of pollution-resistant species, at the relatively cleaner outer estuary. Following intensification of "Still ongoing" rehabilitation studies in 1998, a remarkable day-by-day recovery in marine life has began, in regard to improvements in water quality. Surveys conducted in 2002 using SCUBA, documented the level of diversification of life at the Golden Horn. Extended till Halic, Bridge, all appropriate substratums were intensely covered by macrobenthic forms and particularly filter feeders dominated the plankton-rich ecosystem. Detection of seahorses at the inner-middle parts of the estuary, in addition to numerous fish, invertebrate and macroalgae species, clearly depicted the level of recovery and change in the ecosystem. All results support the existence of a dynamic biological life at the Golden Horn, improving considerably with rehabilitation studies. Achieving the diversity of the 1940s is not possible, since the Black and Marmara seas, highly influencing water quality in the Golden Horn are also suffering from anthropogenic impacts and are far beyond their rich diversity in the 1940s. However, it is obvious that ecosystems should recover when mankind gave a chance to them. Recovery of the recently lifeless Golden Horn in such a short period of time is a very good example.