Strong fisheries management and governance positively impact ecosystem status

Fisheries have had major negative impacts on marine ecosystems, and effective fisheries management and governance are needed to achieve sustainable fisheries, biodiversity conservation goals and thus good ecosystem status. To date, the IndiSeas programme (Indicators for the Seas) has focussed on assessing the ecological impacts of fishing at the ecosystem scale using ecological indicators. Here, we explore fisheries Management Effectiveness' and Governance Quality' and relate this to ecosystem health and status. We developed a dedicated expert survey, focused at the ecosystem level, with a series of questions addressing aspects of management and governance, from an ecosystem-based perspective, using objective and evidence-based criteria. The survey was completed by ecosystem experts (managers and scientists) and results analysed using ranking and multivariate methods. Results were further examined for selected ecosystems, using expert knowledge, to explore the overall findings in greater depth. Higher scores for Management Effectiveness' and Governance Quality' were significantly and positively related to ecosystems with better ecological status. Key factors that point to success in delivering fisheries and conservation objectives were as follows: the use of reference points for management, frequent review of stock assessments, whether Illegal, Unreported and Unregulated (IUU) catches were being accounted for and addressed, and the inclusion of stakeholders. Additionally, we found that the implementation of a long-term management plan, including economic and social dimensions of fisheries in exploited ecosystems, was a key factor in successful, sustainable fisheries management. Our results support the thesis that good ecosystem-based management and governance, sustainable fisheries and healthy ecosystems go together.IOC-UNESCO; EuroMarine; European FP7 MEECE research project; European Network of Excellence Eur-Oceans; FRB EMIBIOS project [212085]info:eu-repo/semantics/publishedVersio

A new species and new records of goatfishes of the genus Parupeneus (Mullidae) from the Indian Ocean, with updated occurrence information for P.jansenii in the Western Pacific

Goatfishes of the genus Parupeneus (Mullidae), from several areas and countries of the Indo-West Pacific, were studied, focusing on species characterized by a symmetrically rounded rear end of the maxilla, which belong to the so-called heptacanthus group. We examined 62 meristic and morphometric characters and colour patterns from 180 specimens from 11 Parupeneus species, using a comprehensive alpha-taxonomy approach. When possible, the data for species represented by wider size ranges were split into two size classes (small-sized fish, < 110 mm SL, vs. large-sized fish ≥ 110 mm SL) to account for allometric changes in body form. A new species, P. inayatae Uiblein & Fahmi, is described, based on a specimen collected in SW Lom-bok, Indonesia, and new records for four species are reported from the Indian Ocean: Parupeneus fraserorum new for Mozambique, P.jansenii new for Myanmar and the NE Indian Ocean, P. nansen new for Tanzania, and P. procerigena new for the Nazareth Bank and Mauritus (Cargados Carajos Bank), Western Indian Ocean (WIO). The record of P.jansenii for Myanmar was compared in detail to 37 conspecific specimens from the entire distribution range (western Indonesia to Japan and Vietnam to NE Australia). The latter revealed two new Pacific records for the Central Philippines and for Shikoku Island, Japan (northernmost record of the species). For each of the eight heptacanthus-group species, diagnoses are provided along with remarks on intraspecific size- and/or population-related variation and/or other noteworthy observations. The new species can be distinguished from all other 32 congeners as follows: dorsal head margin in front of eyes concave shaped; posterior maxilla margin evenly, symmetrically rounded; body, head, and caudal peduncle moderately deep; pectoral and pelvic fins subequal in length; and caudal peduncle clearly deeper than 9.5 % SL; in life a dusky spot on lateral line below interdorsal space, followed posteriorly by a bright orange blotch. Detailed comparisons among all eight heptacanthus-group species and with three other similar and/or co-occurring congeners revealed considerable similarity between two species pairs, P.jansenii (Eastern Indian Ocean and Western Pacific) and P. nansen (WIO), and P. fraserorum and P. procerigena (both from the WIO). The need to further intensify taxonomie studies and accompanying fisheries-biology and ecological studies of goatfishes in the large realm of the Indo-West Pacific is emphasized

Growth, mortality, exploitation rate and recruitment pattern of Octopus cyanea (Mollusca: Cephalopoda) in the WIO region: A case study from the Mafia Archipelago, Tanzania

Octopus cyanea is a commercially important cephalopod in the Western Indian Ocean (WIO) region, but scientific information to inform management strategies for the species is limited. A study was conducted in 2014, 2015, 2017 and 2018 to investigate biological parameters including growth, mortality, exploitation rates and recruitment patterns in the sea around Mafia Archipelago, Tanzania. Virtual population analysis (VPA) indicated differential mortality between two sampling sites; the lowest and highest fishing mortality of F = 1.5yr-1 and F = 2.7yr-1 were observed in Bwejuu (Dorsal mantle length, DMT = 18-20 cm) and Jibondo (DMT = 8-12 cm) fishing villages, respectively. The maximum exploitation rate (Emax), which gives the maximum relative yield per recruit, was estimated at 0.380 and 0.379 for Jibondo and Bwejuu, respectively. The exploitation rates E 0.5, which corresponded to 50% of the unexploited stock relative biomass per recruit, were estimated at 0.248 for Jibondo and 0.247 for Bwejuu. These values differ greatly from the exploitation rates of 0.53 and 0.41 for Jibondo and Bwejuu, respectively, suggesting that the stock of O. cyanea is probably being overfished both in terms of yield per recruit and biomass per recruit. The stock-recruit pattern was observed to be continuous year-round, with the peak being between May and July. Since the peak in recruitment of both areas coincides with the south-east monsoon (SE Monsoon) and the level of maximum sustainable yield has been overshot, it is recommended that management plans are implemented that will reduce effort while increasing biomass, for example, implementing temporal octopus fishery closures at a village level

Determination of Environmental Flows in Data-Poor Estuaries—Wami River Estuary in Saadani National Park, Tanzania

Land use changes and mounting water demands reduce freshwater inflows into estuaries, impairing estuarine ecosystems and accelerating coastal seawater intrusion. However, determining minimum river inflows for management guidelines is hampered by a lack of ecosystem-flow link data. This study describes the development of freshwater inflow guidelines for the Wami Estuary, combining scarce river flow data, hydrological modeling, inferring natural salinity regime from vegetation zonation and investigating freshwater requirements of people/wildlife. By adopting the Building Blocks Methodology, a detailed Environmental Flows Assessment was performed to know the minimum water depth/quality seasonal requirements for vegetation, terrestrial/aquatic wildlife and human communities. Water depth requirements were assessed for drought and normal rainfall years; corresponding discharges were obtained by a hydrological model (HEC-RAS) developed for the river channel upstream of estuary. Recommended flows were well within historically occurring flows. However, given the rapidly increasing water demand coupled with reduction in basin water storage due to deforestation/wetland loss, it is critical to ensure these minimum flows are present, without which essential ecosystem services (fisheries, water quality, mangrove forest resources and wildlife/tourism) will be jeopardized. The EFA process is described in painstaking detail to provide a reference for undertaking similar studies in data-poor regions worldwide