Aquaculture is an increasingly important food-producing sector, providing protein for human consumption. However, marine aquaculture often struggles for space due to the crowded nature of human activities in many marine coastal areas, and because of limited attention from spatial planning managers. Here, we assess the need for coastal spatial planning, emphasising the establishment of suitable areas for the development of marine aquaculture, termed Allocated Zones for Aquaculture (AZAs), in which aquaculture has secured use and priority over other activities, and where potential adverse environmental impacts and negative interactions with other users are minimised or avoided. We review existing examples of marine aquaculture spatial development worldwide and discuss the proper use of site selection in relation to different legal and regulatory requirements. National or regional authorities in charge of coastal zone management should carry out spatial planning defining optimal sites for aquaculture to promote development of sustainable marine aquaculture and avoid conflict with other users, following a participatory approach and adhering to the principles of ecosystem-based management.

-The diversity of Pseudo-nitzschia (Bacillariophyceae) and accumulation of the neurotoxin domoic acid (DA) in two types of shellfish; tuberculate cockles (Acanthocardia tuberculata) and sweet clams (Challista chione) was explored in M'diq Bay, Morocco during 2007. The highest abundances of Pseudo-nitzschia were found during the period from March to October, with peaks occurring in May and September. Toxin analysis showed an accumulation of domoic acid in shellfish sampled during spring and autumn. The maximum toxin concentration was 4.9 mg DA g -1 of the whole tissue recorded in sweet clam during spring. Using transmission electron microscopy, thirteen Pseudo-nitzschia species were identified, eight of which are known as producers of domoic acid: P. multistriata, P. cuspidata, P. galaxiae, P. multiseries, P. pseudodelicatissima, P. pungens var. aveirensis, P. calliantha and P. fraudulenta. The five non-toxic species observed were P. subpacifica, P. arenysensis, P. dolorosa, P. subfraudulenta, and P. cf. caciantha.

Globally, aquaculture contributes to sustainable food and nutritional stability. However, stress conditions constitute a major threat affecting farmed-fish welfare and fish farms’ performances. In this regard, the present study was aimed at measuring and comparing in-situ (offshore) the physiological stress responses caused by recurrent sampling operations for length–weight measurement. Studied fish were European sea bass Dicentrarchus labrax sub-adults and adults reared in intensive farming conditions in M’diq Bay, on the Moroccan Mediterranean coast. The physiological stress response was evaluated by measuring blood biomarkers, including cortisol, glucose, lactate, total cholesterol and total proteins levels, and hematocrit percentage. The hypercortisolemia, hyperglycemia, hyperlactatemia and hypoproteinemia detected in the post-sampling state in both age groups of D. labrax indicated stress tendencies and a high sensitivity to aquaculture practice-related stress factors, with major and minor responses detected in the same age and same stress conditions. It is also interesting to note that the fish age and the time-course of the sampling operation had a statistically significant effect in terms of the physiological response (with p < 0.01 and p < 0.001, respectively). In conclusion, the present study showed that sea bass subjected to various stressful situations in intensive farming conditions displayed a physiological stress response specific to its age, to the individual status, as well as to the duration of stressor.

A study of spat settlement of two mussel species was carried out in Agadir area on the North Atlantic Coast, between Jan 2002 and Jan 2003. The preferred depth of settlement and settlement period of both species were monitored on collectors suspended in offshore at three different depths (1, 5, 10 m). For Perna perna, the effect of season on settlement was consistent, with relatively higher settlement both in spring (286-462 spats.m-1 ) and in summer (406-594 spats.m-1 ). Similar abundances of settlers were found at 1 m and 5 m depth whatever the season, which suggests a homogeneous distribution of settlers of P. perna in the first 5 m of the sea water. For Mytilus galloprovincialis, the settlement was less patchy in time in regard to P. perna (ρ<0.05). Thus, the settlement was continuous from spring to autumn until 10 m depth. The filamentous structures (laces in polypropylene) used in this study are often designed to enhance the amount of settlers, however, the settlement densities of both species were very low. Consequently, the results suggest that larval supply has been the limiting factor in the settlement success, but not the lack of suitable substrates. Moreover, the study area has poor spat falls and seems to be not suitable for collection of mussel spat.

The present study aimed at studying ecological interaction between a fish farm cages located in M’diq bay, in western Moroccan Mediterranean coast, and its local environment. It was carried out in 2013 and 2016 through seabed analysis in terms of organic matter and some nutrients parameters such as Nitrogen and Phosphorus, as well as through monitoring macro-fauna assemblages. The results showed recorded values relatively stable in three years’ interval and have a well-integrated fish farming activity within its ecosystem. Sediment was sandy to sandy shelly types and macro-benthic fauna were composed of six groups, Gastropods, Bivalves, Scaphopoda, Amphipods, Nematoda and Polychaeta. Organic matter and Total Organic Carbon were respectively less than 3.2% and 1.87% and very low comparing with others Mediterranean fish farms sites. Estimation of Nitrogen, Phosphorus and Carbon potential releases of M’diq fish farm gave low data related to its production capacity not exceeding 200 tons by year. Influenced with open sea location and high current state, dispersion pattern of these fish farm discharges seemed to play a key role in keeping lower values. ANOVA analysis showed no significant difference between studied parameters in the five sampling stations comparing with the reference station both on geographical and temporal levels (seasons and years).