The possibility of occurrence of the phenomenon “fishing down marine food webs” in the coastal waters of Hormozgan Province (north of the Persian Gulf and Oman Sea)

We examined the temporal trend in mean trophic level (mTL), trophic category landing (TrC) and landing profile (LP) of the exploited marine community (49 species) in the fishing zone of Hormozgan (north of Persian Gulf and Oman Sea) from 2001 to 2011. LP had an increasing trend (r = 0.88, P<0.001), whereas, mTL of the landings showed a significant decrease from 2001 to 2011 (r = -0.69, P<0.05). We observed a decreasing trend in the landing of carnivores and predators of the upper level food web during the study period, which could be a sign for the phenomenon of fishing down marine food web in the water bodies of Hormozgan Province. The results of cluster analysis and nonmetric dimentional scale divided the composition and amount of landings into two year groups (2001–2007 and 2008–2011). Analysis of similarity revealed a significant difference between these two year groups (r=0.88; P=0.005). Benthosema pterotum and Thunnus albacores were responsible for this dissimilarity in composition and amount of these two groups.