English, CA, Galindo, HM, Grebmeier,JM, Hollowed, AB, Knowlton, N, Polovina,J, Rabalais,NN, Sydeman, WJ, and Talley, LD
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Human-induced threats to turtles, sea birds and other vulnerable species; overview, needs analysis and stakeholder identification South Africa Prepared for the Benguela Current Convention February 2017 Acknowledgement This project of the Benguela Current Convention’s ecosystem-based management programme is made possible by generous support of the Ministry of Foreign Affairs, Norway. …………………………………………………… Disclaimer Any opinions, findings, conclusions or recommendations expressed in this report are those of the authors and do not necessary reflect the views of the Benguela Current Convention and / or Norway. Executive Summary Fisheries and other human activities have direct and indirect impacts on the aquatic and marine ecosystems, which have resulted in growing ecosystem degradation, loss of habitat as well as inadequate management-oriented research, poor long-term monitoring and limited integrated planning of conflicting uses. The focus of this report is the human activities that can be managed and monitored in the BCC environment. The document provides a synthesis of information on human induced threats pertinent to the protection of seabirds, turtles and other vulnerable species, including reference to elasmobranchs, marine mammals and fish species. As the main thrust of the project is to update the National Plan of Action (NPOA) to curb the incidental mortality of seabirds, emphasis has been placed on providing detailed information which will assist in the compilation of the NPOA. Data and suggestions pertinent to the Penguin Biodiversity Management Plan (PMP) and Turtle Biodiversity Management Plan, both developed by the Department of Environmental Affairs (DEA) are also included. Catastrophic incidents such as oil spill disasters and the long-term impact of plastic debris also fall outside the scope of this report. 2 | P a g e Contents Executive Summary ................................................................................................................................. 2 Acronyms ................................................................................................................................................ 6 1. Introduction ..................................................................................................................................... 8 1.1. Review of human threats to the environment of vulnerable marine and seabird species .... 8 1.2. Scope of the NPOA .................................................................................................................. 9 1.3. Human impacts particular to the BCC environment ............................................................. 10 1.4. Existing Legislation ................................................................................................................ 16 2. Primary drivers affecting conservation status of vulnerable marine species other than seabirds, turtles and reptiles, current initiatives and proposed interventions ................................................... 21 2.1. Marine mammals .................................................................................................................. 22 2.1.1. Competition with fisheries for food .............................................................................. 22 2.1.2. By-catch of marine mammals ....................................................................................... 22 2.1.3. Pollution ........................................................................................................................ 25 2.1.4. Climate or anthropogenic induced ecosystem changes ............................................... 25 2.2. Sharks .................................................................................................................................... 25 2.2.1. By-catch of sharks ......................................................................................................... 25 2.2.2. Pollution ........................................................................................................................ 27 2.2.3. Climate change .............................................................................................................. 27 2.3. Seals ...................................................................................................................................... 27 2.3.1. Competition with fisheries for food .............................................................................. 27 2.3.2. Pollution ........................................................................................................................ 28 2.3.3. Habitat loss and disturbance ........................................................................................ 28 2.3.4. Climate change .............................................................................................................. 28 2.4. Line Fishery ........................................................................................................................... 28 2.5. Abalone (adopted from 12) )................................................................................................... 30 2.5.1. Ecosystem interactions – Habitat loss and disturbance ............................................... 31 2.5.2. Pollution ........................................................................................................................ 31 2.5.3. Climate change .............................................................................................................. 31 2.6. West Coast rock lobster ........................................................................................................ 32 2.6.1. Ecosystem interactions and disturbance ...................................................................... 32 3. Overview: Primary threats affecting conservation status of vulnerable seabirds, turtles and reptiles .................................................................................................................................................. 33 3.1. Seabirds ................................................................................................................................. 33 3 | P a g e 3.1.1. Ecosystem and climate changes ................................................................................... 34 3.1.2. Food Web interactions .................................................................................................. 34 3.1.3. Pollution ........................................................................................................................ 35 3.1.4. Habitat loss and disturbance ........................................................................................ 35 3.1.5. Past and current conservation initiatives ..................................................................... 36 3.2. Turtles ................................................................................................................................... 36 3.2.1. Ecosystem changes ....................................................................................................... 36 3.2.2. Food Web interactions .................................................................................................. 37 3.2.3. Pollution ........................................................................................................................ 38 3.2.4. Habitat loss and disturbance ........................................................................................ 39 3.2.5. Climate change .............................................................................................................. 41 3.2.6. Predators ....................................................................................................................... 42 3.2.7. Past and current conservation initiatives ..................................................................... 42 3.3. Stakeholders ......................................................................................................................... 42 4. Relevant Fishery Sectors affecting seabirds and turtles ................................................................ 44 4.1 Hake deep-sea and inshore trawl fisheries (demersal) ........................................................ 46 4.1.1 Introduction ...................................................................................................................... 46 4.1.2 Current information .......................................................................................................... 46 4.1.3 Human impact of by-catch and ghost fishing ................................................................... 47 4.1.4 Current and proposed mitigation measures and interventions ....................................... 48 4.2 Small pelagics ........................................................................................................................ 48 4.2.1 Introduction ...................................................................................................................... 48 4.2.2 Current information .......................................................................................................... 49 4.2.3 Human impact of by-catch and ghost fishing ................................................................... 49 4.3 Pelagic Longline and tuna pole-line ...................................................................................... 51 4.3.1 Introduction .....................................................................................................................