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Invertebrate drift is a key process in riverine ecosystems controlling aquatic invertebrate distribution and availability to fish as prey. However, accurately quantifying drifting invertebrates of all sizes is difficult because the fine-mesh nets required to capture the smallest specimens clog easily, which reduces filtration efficiency and measurement accuracy. To address this problem, we developed a gas-powered pump system that delivers 20 m3/hour of river water through nested 80- and 750-μm-mesh nets suspended in the air. We compared 17 pumped samples with those obtained by adjacent, conventional deployment of a 250-μm drift net in a clear-water Alaskan river during both low and high flows. Our drift pump system sampled a geometric mean drift concentration of 467 invertebrates m−3 (maximum 5637 m−3) – eleven times the mean concentration of 42 m−3 estimated using the drift net. Invertebrates ≤ 3 mm long, primarily chironomids, comprised the entire difference between methods. Investigators for whom the drift of 0.5–3 mm invertebrates might be relevant (e.g., those applying foraging models for juvenile drift-feeding fishes) should consider using a pump or similar aerial filtration method to quantify small invertebrate drift, lest they underestimate it by an order of magnitude.

PurposeDrift net fishing activities have undergone a thorough revision at a European Union level, since authorities argue that several loopholes still exist in the legislation that allow small-scale fisheries to use these gears. High incidental catches, or the lack of selectivity, are some of the primary scientific criteria behind this discussion. This new framework is of particular interest in the region of Galicia (NW Spain) due to the social importance of small-scale fishing vessels using drift nets. In fact, over 400 vessels have a licence to capture European pilchard (Sardina pilchardus) with a fishing gear called xeito, which is a small-scale drift net.MethodsThe main goal of this article is to provide stakeholders in the fishing sector with environmentally relevant results regarding the life cycle impacts linked to fishing practices performed by small-scale vessels using the xeito gear to target European pilchard. We hypothesize that environmental impacts computed with LCA will provide additional insights to the sustainability of the pilchard small-scale fishery in NW Spain, adding a series of criteria that may be useful for policy-makers to determine the consequences of forbidding this type of drift netting in the future.Results and discussionResults show that environmental impacts across impact categories and operational activities do not differ much from that of other similar fishing fleets examined in recent years, with fuel for propulsion being the main environmental burden in most impact categories. When conducting a statistical analysis, no significant difference in energy use was identified between this small-scale fleet and purse seiners targeting pilchard in Galicia. Moreover, the results obtained demonstrate, in line with previous studies, that European pilchard is still an energy-efficient source of animal protein option as compared to demersal fish alternatives, crustaceans, or livestock.ConclusionsThe results do not indicate that European pilchard landed with small-scale drift nets generates higher environmental life cycle impacts than pilchard landed by purse seiners in NW Spain. However, longer time frames for the analysis should be performed to attain results with lower uncertainty.

Summary The focus was on the length–weight relationships of three schizothoracinae species endemic to Tibet, including Schizothorax oconnori Lloyd, 1908, Ptychobarbus dipogon (Regan, 1905) and Schizopygopsis younghusbandi Regan, 1905, all of which are characterized by slow growth, late maturation and vulnerability to the environment (Ma et al., 2010, 2012; Duan et al., 2014). Among them, Schizothorax oconnori is an endangered fish and listed in the China species Red List (Wang and Xie, 2004, 2009). Samples were obtained by drift net fishing (mesh size 2 cm × 3 cm; 50 m net length) in November 2008. The r2 value was 0.94, 0.97, 0.98 and the b value 3.51, 3.12, 3.16, representing Schizothorax oconnori, Ptychobarbus dipogon, and Schizopygopsis younghusbandi, respectively.

This paper reports the length–weight relationships for six fish species belonging to the Cyprinidae from the middle of the Yalu Tsangpo River in China. Samples were obtained by electroshock and drift net fishing techniques (mesh size 2 cm × 3 cm; 200 m net length) in April and September to October 2014. Length–weight relationships estimates for these species were not available in FishBase. A total of 737 specimens were used to estimate the a and b parameters. New maximum total lengths are also reported for six species. The r² values range from 0.98 to 0.99. Values of b vary from 2.88 to 3.19.

Globally, 6.4 million tons of fishing gear are lost in the oceans annually. This gear (i.e., ghost nets), whether accidently lost, abandoned, or deliberately discarded, threatens marine wildlife as it drifts with prevailing currents and continues to entangle marine organisms indiscriminately. Northern Australia has some of the highest densities of ghost nets in the world, with up to 3 tons washing ashore per kilometer of shoreline annually. This region supports globally significant populations of internationally threatened marine fauna, including 6 of the 7 extant marine turtles. We examined the threat ghost nets pose to marine turtles and assessed whether nets associated with particular fisheries are linked with turtle entanglement by analyzing the capture rates of turtles and potential source fisheries from nearly 9000 nets found on Australia's northern coast. Nets with relatively larger mesh and smaller twine sizes (e.g., pelagic drift nets) had the highest probability of entanglement for marine turtles. Net size was important; larger nets appeared to attract turtles, which further increased their catch rates. Our results point to issues with trawl and drift‐net fisheries, the former due to the large number of nets and fragments found and the latter due to the very high catch rates resulting from the net design. Catch rates for fine‐mesh gill nets can reach as high as 4 turtles/100 m of net length. We estimated that the total number of turtles caught by the 8690 ghost nets we sampled was between 4866 and 14,600, assuming nets drift for 1 year. Ghost nets continue to accumulate on Australia's northern shore due to both legal and illegal fishing; over 13,000 nets have been removed since 2005. This is an important and ongoing transboundary threat to biodiversity in the region that requires attention from the countries surrounding the Arafura and Timor Seas.

In 1992, the UN banned the use of large‐scale pelagic driftnets on the high seas (UNGA Resolution 46/215). Three decades later, however, drift gillnets remain one of the primary fishing gears in the Indian Ocean, accounting for approximately 30% of tuna catches in this ocean. Recent estimates indicate that several million small cetaceans have been killed in Indian Ocean gillnets over the past few decades. National agencies and the regional fisheries management organization charged with managing tuna fisheries, the Indian Ocean Tuna Commission, have yet to effectively document the bycatch of small cetaceans in these fisheries. Here, we review current information on cetacean bycatch in Indian Ocean drift gillnets and propose potential solutions to this important conservation issue.

Illegal driftnetting causes each year several entanglements and deaths of sperm whales in different Mediterranean areas, primarily in the Tyrrhenian Sea. In summer 2020, during the June-July fishing season, two sperm whales were found entangled in illegal driftnets in the Aeolian Archipelago waters, Southern Italy. These two rare events were an exceptional chance to collect behavioural and acoustics data about entangled sperm whales. We analysed 1132 one-minute sets of breathing/behavioural data and 1575 minutes of acoustic recording, when the whales were found entangled, during the rescue operation, immediately after release, and in the days thereafter. The first whale was generally quiet showing a general status of debilitation/weakness, numerous skin lesions, and low breathing rate (0.31 (0.60)); it collaborated during rescue operations. On the contrary, the second whale showed a high level of agitation with a high breathing rate (1.48 (1.31)) during both the entanglement period and the net cutting operations, vigorously moving its fluke and pectoral fins, opening its mouth, sideway rolling or side fluking and frequently defecating. Acoustically, the first whale produced mainly single clicks in all phases except for two series of creaks during rescuing operations while the second whale produced a wide range of vocalizations (single clicks, likely either slow clicks or regular clicks, creaks, and codas). Our observations indicate that acoustics, respiratory and behavioural parameters may be useful to monitor the physical/physiological status of sperm whales during disentanglement operations.

Background: Ischemic heart disease (IHD) is the leading cause of mortality and disability worldwide. This study aimed to investigate global trends in IHD mortality across 204 countries and territories over the past 30 years and explore the influence of age, period, birth, and cohort effects on mortality. Methods: IHD mortality data were retrieved from the Global Burden of Disease (GBD) 2019 study. Temporal trends in the number of deaths, all-age mortality rates, and age-standardized mortality rates were assessed across countries grouped by sociodemographic index (SDI) quintiles. To quantify changes over time, we fitted age–period–cohort (APC) models and derived overall annual percentage changes (net drift) and age-specific annual percentage changes (local drift). The APC model was then used to distinguish the independent effects of age, period, birth, and cohort on IHD mortality trends. Results: The annual global IHD deaths increased from 5.70 million (95% uncertainty interval (UI): 5.41–5.90) to 9.14 million between 1990 and 2019 (95% UI: 8.40–9.74). All-age mortality rates also rose significantly, with a notable shift in deaths toward older populations (≥70 years). The global net drift in IHD mortality declined by 1.10% annually (95% confidence interval (CI): –1.17% to –1.04%), with high-SDI countries experiencing the greatest decline (–2.84%, 95% CI: –3.05% to –2.64%). Age, period, and birth cohort effects manifested a general declining trend. The largest positive net drift was observed in the Philippines (3.60%, 95% CI: 3.33%–3.86%). Key global risk factors included hypertension, elevated low-density lipoprotein cholesterol, ambient particulate matter pollution, and smoking. However, low temperatures were the leading environmental risk factor in high-SDI countries. Conclusions: From 1990 to 2019, the global burden and temporal trends for IHD mortality varied substantially across SDI quintiles, sex, geographic regions, and countries. These disparities underscore the need for region-specific, risk-differentiated, and cost-effective interventions to prevent and manage IHD. Moreover, strengthening primary healthcare, improving health system responsiveness, and enhancing health promotion and prevention efforts are critical, especially in regions where IHD mortality remains stable or is increasing.

Background High sodium intake is a recognized risk factor for increased gastric cancer mortality. This study examines the trends and distribution of stomach cancer burden associated with high sodium intake from 1990 to 2021, with a focus on its relationship with age, period, and birth cohort. Methods Utilizing data from the 2021 Global Burden of Disease study, we applied an age-period-cohort model to conduct statistical analysis. We calculated age, period, and cohort effects, as well as net drift (overall annual percentage change), for gastric cancer deaths and disability-adjusted life years (DALYs) associated with high sodium intake across 204 countries and regions. Results In 2021, 7.93% of global gastric cancer deaths and 7.92% of DALYs were linked to high sodium intake. Populations in East Asia and those with a high-middle Sociodemographic Index (SDI) bore the heaviest burden. Over the 32-year period, the global age-standardized mortality rate [Net drift = -2.33(95%CI:-2.37 to -2.28)] and age-standardized DALYs rate [Net drift = -2.56(95%CI:-2.65 to -2.47)] generally demonstrated a declining trend, particularly in high SDI regions [Net drift =—2.91 (95%CI: -3.02 to -2.81)]. China, as a representative country, exhibited unfavorable age, period, and cohort effects. Future projections suggest further declines in mortality and DALYs numbers, along with corresponding age-standardized rates. Conclusion Despite ongoing global efforts to reduce sodium intake, gastric cancer remains a significant public health challenge, especially in East Asia. The findings underscore the necessity of developing targeted prevention strategies for high-risk groups, such as the elderly and males, to mitigate the global burden of gastric cancer.

1. Over the last few decades, evidence of marine vertebrate by catch has been collected for a range of industrial fisheries. It has recently been acknowledged that large impacts may also result from similar interactions with small-scale fisheries (SSF) due largely to their diffuse effort and large number of vessels in operation. Marine mammals, seabirds, turtles as well as some shark species have been reported as being impacted by SSF worldwide. 2. From 2000 to 2007, we used both shore-based and onboard observer programmes from three SSF ports in Peru to assess the impact on marine turtles of small-scale longline, bottom set nets and driftnet fisheries. 3. We reported a total of 807 sea turtles captured, 91·8% of which were released alive. For these three sites alone, we estimated c. 5900 turtles captured annually (3200 loggerhead turtles Caretta caretta, 2400 green turtles Chelonia mydas, 240 olive ridleys Lepidochelys olivácea and 70 leatherback turtles Dermochelys coriacea). 4. SSF in Peru are widespread and numerous (> 100 ports, > 9500 vessels, > 37 000 fishers), and our observed effort constituted c. 1 % of longline and net deployments. We suggest that the number of turtles captured per year is likely to be in the tens of thousands. Thus, the impacts of Peruvian SSF have the potential to severely impact sea turtles in the Pacific especially green, loggerhead and leather back turtles. 5. Implications of the human use of turtle products as 'marine bushmeat' are also raised as an important issue. Although such utilization is illegal, it is difficult to foresee how it can be managed without addressing the constraints to the livelihoods of those depending almost entirely on coastal resources. 6. Syntheses and applications. Our analysis demonstrates that, despite logistical challenges, it is feasible to estimate the bycatch per unit of effort in SSF by combining methods that account for fishing effort and bycatch, such as using onboard and shore-based observers. We highlight sea turtle bycatch in SSF in the southeast Pacific as a major conservation concern but also suggest possible paths for mitigation.