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The Peruvian grunt, Anisotremus scapularis, is beginning its domestication as a candidate species for marine aquaculture. The optimal management of fingerling production requires precise knowledge on early development. Herein, we report the methodology for capturing and conditioning wild specimens to find a viable broodstock. The speed of capture and transportation (about 30 min), the post capture preventive treatment (60 min with tetracycline), and the 6-days preventive antiparasitic treatment (29 ppm formalin) maximized survival and a rapid feeding adaptation. Progressive diets based on the copepod Emerita analoga, fish meal, pellets and processed feedstuff prompted the spontaneous broodstock spawning 7 months post-capture. The interannual spawning of this broodstock since September 2016 indicated the optimal control of its reproduction in captivity. The morphogenetic process of the embryo lasted 42 h at 18 °C compared to (31–41) h at 19 °C in northern Peruvian latitudes. The knowledge generated allowed us to work out broodstock and egg management protocols in southern Pacific latitudes (southern Peru and northern Chile). Such protocols would help to escalate larval and juvenile production and to alleviate fishing pressure on the overexploited Peruvian grunt population.

A rare subseasonal-to-seasonal phenomenon – two consecutive flash drought events interrupted by a period of recovery – occurred across eastern Oklahoma, Arkansas, and southern Missouri, spanning the summer and early fall of 2022. These flash drought events (the first in June–July, the second in August–September) led to severe (D2) and extreme (D3) drought conditions via the United States Drought Monitor across much of the region following the first period of rapid drought intensification, and extreme (D3) and exceptional (D4) drought conditions by the end of the second event. A notable driver of both flash drought events included a persistent upper-level ridge either centered over or shifted west and upstream of the flash drought region, leading to broad-scale subsidence and reduced mid-level moisture which acted to limit precipitation development and increase evaporative demand. In addition, several heatwave events developed during the warm season in 2022 and either (1) acted to drive flash drought development via increased evaporative demand or (2) were enhanced by land surface desiccation and land-atmosphere feedbacks following rapid drought intensification. Furthermore, S2S composite forecasts predicted drought development for both events. However, only 20% of the ensembles predicted rapid drought development associated with flash drought for the first event and 16% of the ensembles predicted rapid drought development during the second event. This result highlights a key challenge in S2S prediction of rapidly developing drought conditions versus that of more conventional and slower drought development. The ensembles that did predict rapid drought intensification were associated with the forecasting of positive 500 hPa geopotential height anomalies over the south-central United States (first event) or an amplified wave pattern centered over the west-central United States (second event). Lastly, the compounding effects of two flash droughts in a single warm season led to substantial impacts on agricultural, environmental, and hydrologic sectors across the region.

The Peruvian grunt Anisotremus scapularis is one of the most appreciated fish in Peruvian national markets. However, its reduced and irregular fishery is a paradigm of illegal, unreported, and unregulated fishing (IUU) in the Peruvian–Chilean coastal region. An important technological advancement has been achieved in the last decade in capture, management, nutrition, and broodstock maintenance to boost pilot experiences on the aquaculture of this species. Therefore, it is pertinent to evaluate the economic viability of this candidate species to identify cultivation bottlenecks, optimize the process, and assess the transfer feasibility of the technical know-how to interest groups. In this study, we performed a sensitivity analysis to assess how market price and production size should make its commercialization profitable. We show that the use of photovoltaic solar panels and a raw production cycle of 15 months enables profitability at a ~400 k unit farm size at a commercial market price of 6.67 USD/kg, i.e., B/C = USD 1.14. Both, time to market and market price exerted the highest influence on the value of grunt farms; whereas, a reduction of the production cycle to 12 months by seed selection, optimized rearing conditions, and nutritional diets also provides a profitable investment, i.e., NPV = USD 287,054 with an IRR = 23.71% at a discount rate of 10% and B/C = USD 1.15. These scenarios pave the way for the transfer of technological know-how to entrepreneurial initiatives in the economically depressed coastal region of the Atacama Desert.