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Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Management reform has the potential to rebuild fisheries and increase long-term harvest and profitability. But timing is critical: delaying reform implementation significantly reduces the potential socio-economic and biological benefits of improved management. This study models the costs of delaying reform in terms of annual biomass, harvest, and profit for 28 Mexican fisheries, parameterized using novel, fishery-specific data. Three types of reforms are examined: 1) harvest policy, 2) elimination of illegal fishing, and 3) implementation of rights-based fisheries management. The harvest policies examined in this analysis are status quo (no reform), F MSY , and economically optimal fishing mortality. The results show that prompt management reforms lead to improved annual aggregate biomass, harvest, and profit over time. However, delaying reform results in substantial costs. Just a 5-year delay of the implementation of comprehensive reform leads to a 51 million USD loss to average annual profits. Without reform, stock status can continue to decline, and the recovery of harvests and profits are further delayed. Over a given time-horizon, delayed reforms can dramatically reduce the number of healthy stocks. The results demonstrate that delayed reform can significantly diminish potential benefits that could be secured through improved management; this highlights the importance of prompt timing considerations during policy reform. [ABSTRACT FROM AUTHOR]

Copyright of Economía, Sociedad y Territorio is the property of El Colegio Mexiquense and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The importance of mucus produced by jellyfish species remains as understudied as their feeding behavior. Here, we study medusae under captivity, ascertain the role of mucus, and describe its feeding behavior. Between February and March 2019, live adult cannonball jellyfish, Stomolophus sp. 2, were collected in Las Guásimas Bay (Gulf of California, Mexico) and were offered fish eggs, mollusk "D" larvae, or Artemia nauplii in 4-day trials. Descriptions of feeding structures were provided for S. sp. 2. Digitata adhere food and scapulets fragment them, which, driven by water flow, pass via transport channels to the esophagus and the gastrovascular chamber where food is digested. Due to stress by handling, medusae produced mucus and water, lost feeding structures, and decreased in size. Based on our observations and a thorough literature review, we conclude that the production of mucus in S. sp. 2 plays several roles, facilitating capture and packing of prey, acting as a defense mechanism, and facilitating sexual reproduction; the latter improves the likelihood of a population persisting in the long run, because fertilized oocytes in mucus transform to planulae, settle, and transform into asexually reproducing polyps. Polyps live longer than the other life stages and are more resistant to adverse environmental conditions than the medusoid sexual stage. [ABSTRACT FROM AUTHOR]

The trajectory of the cannonball jellyfish (Stomolophus sp. 2) fishery in the central portion of Mexico's Gulf of California is an all too familiar one, consisting of exploration, rapid development, and, as of now, subsequent collapse. As all of the product is exported to markets overseas, buyers have little incentive to conserve local stocks, with jellyfish now exhibiting a global-scale sequential exploitation experienced by many other marine resources. While historical data gaps are often used as excuses for overexploitation after the fact, the emergence of this modern fishery was accompanied by relatively broad research interest; however, recommendations based on sound science were not followed. The resultant paucity of policy goals, regulation, cooperation, compliance, and enforcement has resulted in the mismanagement of a potentially lucrative fishery for future generations. There are always myriad challenges when attempting to manage a nascent fishery with high uncertainty, particularly in a developing country, and this case further highlights the importance of taking a precautionary approach to emerging resource extraction. Multiple prior experiences with similar outcomes should behoove regulators and managers to exhibit extra caution, and yet, sustainability and forethought still appear to be secondary to short-term profits and employment support. Nonetheless, it is perhaps not too late for cannonball jellyfish fisheries in the Gulf of California, and there are opportunities to implement management strategies that promote collaboration, research, and sustainability. This fishery requires a new management regime that embraces adaptive co-management in order to provide benefits to locals, both now and in the future. • Jellyfish are targeted for food exports in Mexico's Gulf of California. • Catches for one of the targeted species have declined, possibly due to overfishing. • Management challenges are complex due to natural and social factors. • Future strategies should include stakeholder collaboration and adaptive co-management. [ABSTRACT FROM AUTHOR]