{'fraction_non_alphanumeric': 0.03170028818443804, 'fraction_numerical': 0.011527377521613832, 'mean_word_length': 5.550314465408805, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
History and development of shellfish cultivation in Walvis Bay, Namibia.

Abstract
 Namibia is one of the countries in Africa with a favourable natural environment for mariculture operations, particularly shellfish production. The nutrient-rich Benguela upwelling system of the Atlantic Ocean gives the Namibian coast a competitive advantage over other worldwide producers of shellfish, especially, oysters, mussels, abalone, scallops and others. Walvis Bay is Namibia 's biggest harbour town on the western Atlantic coast, where a well established commercial fisheries industry exists along side the country's largest mariculture centre. Other centres of mariculture production include Luderitz, (another fishing town on the southernmost part of the coastline), Swakopmund (30 km from Walvis Bay) and Henties Bay (100 km from Walvis Bay). Shellfish production in Walvis Bay is principally oyster farming and the species produced are the Pacific Oyster (Crassotrea gigas) and the European flat oyster (Ostrea edulis). These have been described as the best oysters in the world due to their exceptional taste and favourable meat-to-shell ratio (Hempel, 2006) and Namibia was ranked amongst the top 20 world leading exporters of oysters (FAO FishSTAT Commodities and Trade, 2006). However, production in 2008 significantly declined due to unexpected harmful algal blooms, the so called red tide phenomenon that resulted in the death of over 75% of all farmed oyster stock. Farmers are currently recuperating from this catastrophe. Besides oysters, mariculture production of other shellfish species in Walvis Bay is negligible but includes the Black mussel (Choromytilus meridionalis), the indigenous clams (Venerupis spp), indigenous scallops (Pecten spp). Cultivation of other shellfish such as abalone (Haliotis midae) and finfish such as Cobia (Rachycentron canadum), dusky kob (Argyrosomus japonicus) and turbot (Psetta maxima) is still being investigated. So far, the mariculture of shellfish in Walvis Bay is believed to have created over 120 jobs, both directly and indirectly.