Increased external nutrient loads of anthropogenic origin, especially those of phosphorus (P), were one of the major causes of eutrophication during the first half of the twentieth century in Europe. They led to deterioration of lake ecosystems, particularly including noxious blooms of (potentially toxic) cyanobacteria. From the 1970-1980s, strategies to decrease the phosphorus loads from sewage were increasingly implemented, among them are the ban of phosphates in detergents, the expansion of sewer systems and improvement in wastewater treatment to remove nutrients. Case studies of eight lakes, whose response to point source reduction of phosphorus was observed over decades, show that a pronounced reduction of the phosphorus load from point sources can be achieved either by the diversion of inflows carrying high loads, by upgraded sewage treatment, or by phosphorus precipitation in the major tributary directly before its inflow into the water body. Outcomes demonstrate that in order to effectively control cyanobacterial blooms, the measures taken need to reduce in-lake concentrations of total phosphorus below 20-50 lg L -1 , with this threshold varying somewhat between lakes depending in particular on hydromorphological and biological conditions. Whether and when load reduction succeeds in controlling cyanobacteria depends primarily on the load

In Belize, the commercial harvest of spiny lobsters has occurred for ∼100 years, provides critical livelihoods, and is the primary seafood export. We determined the first empirical estimate of size at maturity in Belize as well as eight fishery status indicators on several fishing grounds. The carapace lengths (CLs) at 50% maturity varied between males (98 mm) and females (86 mm) and are higher than the existing legal minimum of 76 mm. Time series analysis indicated decreasing proportions of mature individuals, decreasing size, and low spawning potential ratios (SPR) as well as high fishing mortality within fishing grounds. The pattern of decline in population status indicators across fishing grounds is consistent with a historical expansion of effort from north to south and offshore. Many indicators of population status within fishing grounds were improved with increasing area of replenishment zone and opposite to the historical expansion. However, overfishing is a problem across all areas examined. An increase in the legal minimum CL to 86 mm and examination of a maximum size limit will likely have significant positive effects on productivity and SPR, respectively, as well as protecting the pivotal role of spiny lobsters within the ecosystem.

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1. Many species targeted by multi-gear small-scale fisheries in developing countries are poorly studied in terms of fisheries sustainability even as their contributions to biodiversity, livelihoods, export earnings and food security are well documented.2. This study presents new information on more than 150 fish species that constitute the bulk of small-scale fishery landings in Belize and on the Pacific coast of Guatemala to provide guidance for improved biodiversity conservation and fisheries management. This includes a number of species listed as threatened on the IUCN Red List and Appendix II of CITES.3. Simple, length-based approaches and thresholds of size at maturity show that many of the elasmobranch and bony fish species examined have many immature individuals landed (Belize 51%, Guatemala 77%) across several gears. 4. In both countries, maximum size is negatively correlated with the intensity of overfishing for several common metrics: proportions of mature, optimal sized and mega-spawners. The disproportionate removal of the largest species first will have cascading effects on biodiversity, community structure and species interactions, as well as livelihood opportunities and food security for fishing communities. Status indicators, such as fishing mortality rate relative to natural mortality rateand estimates of depletion based on lengths are sensitive to the assumed values of life history parameters, indicating the importance of improved data on growth, maturity and mortality for these populations.6. Our study emphasizes the use of a combination of fisheries conservation strategies, including size and effort controls, in conjunction with the closed area concept (i.e. marine protected areas) and meaningful consultation with resource users in order to maximize benefits for nature and people.Alexander Tewfik and Elizabeth A. Babcock contributed equally to this research.