Rates of biodiversity loss are higher in freshwater ecosystems than in most terrestrial or marine ecosystems, making freshwater conservation a priority. However, prioritization methods are impeded by insufficient knowledge on the distribution and conservation status of freshwater taxa, particularly invertebrates. We evaluated the extinction risk of the world's 590 freshwater crayfish species using the IUCN Categories and Criteria and found 32% of all species are threatened with extinction. The level of extinction risk differed between families, with proportionally more threatened species in the Parastacidae and Astacidae than in the Cambaridae. Four described species were Extinct and 21% were assessed as Data Deficient. There was geographical variation in the dominant threats affecting the main centres of crayfish diversity. The majority of threatened US and Mexican species face threats associated with urban development, pollution, damming and water management. Conversely, the majority of Australian threatened species are affected by climate change, harvesting, agriculture and invasive species. Only a small proportion of crayfish are found within the boundaries of protected areas, suggesting that alternative means of long-term protection will be required. Our study highlights many of the significant challenges yet to come for freshwater biodiversity unless conservation planning shifts from a reactive to proactive approach.

Lobsters are important resources throughout the world's oceans, providing food security, employment, and a trading commodity. Whereas marine biologists generally focus on modern impacts of fisheries, here we explore the deep history of lobster exploitation by prehistorical humans and ancient civilizations, through the first half of the 20th century. Evidence of lobster use comprises midden remains, artwork, artefacts, writings about lobsters, and written sources describing the fishing practices of indigenous peoples. Evidence from archaeological dig sites is potentially biased because lobster shells are relatively thin and easily degraded in most midden soils; in some cases, they may have been used as fertilizer for crops instead of being dumped in middens. Lobsters were a valuable food and economic resource for early coastal peoples, and ancient Greek and Roman Mediterranean civilizations amassed considerable knowledge of their biology and fisheries. Before European contact, lobsters were utilized by indigenous societies in the Americas, southern Africa, Australia, and New Zealand at seemingly sustainable levels, even while other fish and molluscan species may have been overfished. All written records suggest that coastal lobster populations were dense, even in the presence of abundant and large groundfish predators, and that lobsters were much larger than at present. Lobsters gained a reputation as “food for the poor” in 17th and 18th century Europe and parts of North America, but became a fashionable seafood commodity during the mid-19th century. High demand led to intensified fishing effort with improved fishing gear and boats, and advances in preservation and long-distance transport. By the early 20th century, coastal stocks were overfished in many places and average lobster size was significantly reduced. With overfishing came attempts to regulate fisheries, which have varied over time and have met with limited success.

The spiny lobsters Panulirus ornatus and Panulirus homarus are important developing tropical aquaculture species, with high demand and limited supply. The established industry in Vietnam relies on wild‐caught mixed seafood bycatch as feed, a practice linked to water quality degradation and potentially disease proliferation in lobster aquaculture, necessitating formulated feed development. The emerging Indonesian and Australian industries lack the crustacean and mollusc component of the seafood bycatch used in Vietnam, increasing the need for manufactured feeds. The development of such feeds is reliant on knowledge of nutrient requirements, ingredient quality, physical feed requirements, and the link between feeding behaviour and feeding methods. This review will elaborate on the development of these knowledge areas to date and outline the two main reference diet recipes that are available as the basis for future research. Research to date has focused on developing a feed recipe that will be consumed and supports adequate growth rather than steering commercial least‐cost formulation practices. Future research is clearly needed to inform formulation, but equally an understanding of the disparate emerging lobster farming industries and their drivers for the adoption of formulated feeds is required to ensure that such research is applied. This will require engagement throughout the supply chain to ensure that research is implementable and to address farmer perception toward formulated feeds. Technical aspects of feed manufacture and scale‐up of feed developments will be critical to the adoption of research results, while validation through semi‐commercial benchmarks and demonstration farm models are expected to increase commercial uptake of developed feeds.