Overfishing is the primary cause of marine defaunation, yet declines in and increasing extinction risks of individual species are difficult to measure, particularly for the largest predators found in ...the high seas
. Here we calculate two well-established indicators to track progress towards Aichi Biodiversity Targets and Sustainable Development Goals
: the Living Planet Index (a measure of changes in abundance aggregated from 57 abundance time-series datasets for 18 oceanic shark and ray species) and the Red List Index (a measure of change in extinction risk calculated for all 31 oceanic species of sharks and rays). We find that, since 1970, the global abundance of oceanic sharks and rays has declined by 71% owing to an 18-fold increase in relative fishing pressure. This depletion has increased the global extinction risk to the point at which three-quarters of the species comprising this functionally important assemblage are threatened with extinction. Strict prohibitions and precautionary science-based catch limits are urgently needed to avert population collapse
, avoid the disruption of ecological functions and promote species recovery
.
The process of understanding the rapid global decline of sawfishes (Pristidae) has revealed great concern for their relatives, the wedgefishes (Rhinidae) and giant guitarfishes (Glaucostegidae), not ...least because all three families are targeted for their high‐value and internationally traded ‘white’ fins.
The objective of this study was to assess the extinction risk of all 10 wedgefishes and six giant guitarfishes by applying the International Union for Conservation of Nature (IUCN) Red List Categories and Criteria, and to summarize the latest understanding of their biogeography and habitat, life history, exploitation, use and trade, and population status. Three of the 10 wedgefish species had not been assessed previously for the IUCN Red List.
Wedgefishes and giant guitarfishes have overtaken sawfishes as the most imperilled marine fish families globally, with all but one of the 16 species facing an extremely high risk of extinction through a combination of traits: limited biological productivity; presence in shallow waters overlapping with some of the most intense and increasing coastal fisheries in the world; and overexploitation in target and by‐catch fisheries, driven by the need for animal protein and food security in coastal communities and the trade in meat and high‐value fins.
Two species with very restricted ranges, the clown wedgefish (Rhynchobatus cooki) of the Malay Archipelago and the false shark ray (Rhynchorhina mauritaniensis) of Mauritania, may be very close to extinction.
Only the eyebrow wedgefish (Rhynchobatus palpebratus) is not assessed as Critically Endangered, with it occurring primarily in Australia where fishing pressure is low and some management measures are in place. Australia represents a ‘lifeboat’ for the three wedgefish and one giant guitarfish species occurring there.
To conserve populations and permit recovery, a suite of measures will be required that will need to include species protection, spatial management, by‐catch mitigation, and harvest and international trade management, all of which will be dependent on effective enforcement.
The deep ocean is the last natural biodiversity refuge from the reach of human activities. Deepwater sharks and rays are among the most sensitive marine vertebrates to overexploitation. One-third of ...threatened deepwater sharks are targeted, and half the species targeted for the international liver-oil trade are threatened with extinction. Steep population declines cannot be easily reversed owing to long generation lengths, low recovery potentials, and the near absence of management. Depth and spatial limits to fishing activity could improve conservation when implemented alongside catch regulations, bycatch mitigation, and international trade regulation. Deepwater sharks and rays require immediate trade and fishing regulations to prevent irreversible defaunation and promote recovery of this threatened megafauna group.
Chondrichthyan fishes are among the most threatened vertebrates on the planet because many species have slow life histories that are outpaced by intense fishing. The Western Central Atlantic Ocean, ...which includes the Greater Caribbean, is a hotspot of chondrichthyan biodiversity and abundance, but has been characterized by extensive shark and ray fisheries and a lack of sufficient data for effective management and conservation. To inform future research and management decisions, we analysed patterns in chondrichthyan extinction risk, reconstructed catches and management engagement in this region. We summarized the extinction risk of 180 sharks, rays and chimaeras, including 66 endemic and 14 near‐endemic species, using contemporary IUCN Red List assessments. Over one‐third (35.6%) were assessed as Vulnerable, Endangered or Critically Endangered, primarily due to overfishing. Reconstructed catches from 1950 to 2016 peaked in 1992, then declined by 40.2% thereafter. The United States, Venezuela and Mexico were responsible for most catches in the region and hosted the largest proportions of the regional distributions of threatened species, largely due to having extensive coastal habitats in their Exclusive Economic Zones. The quantity and taxonomic resolution of fisheries landings data were poor in much of the region, and national‐level regulations varied widely across jurisdictions. Deepwater fisheries represent an emerging threat, although many deepwater chondrichthyans currently have refuge beyond the depths of most fisheries. Regional collaboration as well as effective and enforceable management informed by more complete fisheries data, particularly from small‐scale fisheries, are required to protect and recover threatened species and ensure sustainable fisheries.
Sharks and rays are key functional components of coral reef ecosystems, yet many populations of a few species exhibit signs of depletion and local extinctions. The question is whether these declines ...forewarn of a global extinction crisis. We use IUCN Red List to quantify the status, trajectory, and threats to all coral reef sharks and rays worldwide. Here, we show that nearly two-thirds (59%) of the 134 coral-reef associated shark and ray species are threatened with extinction. Alongside marine mammals, sharks and rays are among the most threatened groups found on coral reefs. Overfishing is the main cause of elevated extinction risk, compounded by climate change and habitat degradation. Risk is greatest for species that are larger-bodied (less resilient and higher trophic level), widely distributed across several national jurisdictions (subject to a patchwork of management), and in nations with greater fishing pressure and weaker governance. Population declines have occurred over more than half a century, with greatest declines prior to 2005. Immediate action through local protections, combined with broad-scale fisheries management and Marine Protected Areas, is required to avoid extinctions and the loss of critical ecosystem function condemning reefs to a loss of shark and ray biodiversity and ecosystem services, limiting livelihoods and food security.
Abusive head trauma (AHT) remains a major pediatric problem with diagnostic challenges. A small pilot study previously associated subcortical brain injury with AHT.
To investigate the association of ...subcortical injury on neuroimaging with the diagnosis of AHT.
Children <3 years with acute TBI admitted to 18 PICUs between 2011 and 2021.
Secondary analysis of existing, combined, de-identified, cross-sectional dataset.
Deepest location of visible injury was characterized as scalp/skull/epidural (n = 170), subarachnoid/subdural (n = 386), cortical brain (n = 170), or subcortical brain (n = 247) (total n = 973). Subcortical injury was significantly associated with AHT using both physicians' diagnostic impression (OR: 8.41 95 % CI: 5.82–12.44) and a priori definitional criteria (OR: 5.99 95 % CI: 4.31–8.43). Caregiver reports consistent with the child's gross motor skills and historically consistent with repetition decreased as deepest location of injury increased, p < 0.001. Patients with subcortical injuries were significantly more likely to have traumatic extracranial injuries such as rib fractures (OR 3.36, 95 % CI 2.30–4.92) or retinal hemorrhages (OR 5.97, 95 % CI 4.35–8.24), respiratory compromise (OR 12.12, 95 % CI 8.49–17.62), circulatory compromise (OR 6.71, 95 % CI 4.87–9.29), seizures (OR 3.18, 95 % CI 2.35–4.29), and acute encephalopathy (OR 12.44, 95 % CI 8.16–19.68).
Subcortical injury is associated with a diagnosis of AHT, historical inaccuracies concerning for abuse, traumatic extracranial injuries, and increased severity of illness including respiratory and circulatory compromise, seizures, and prolonged loss of consciousness. Presence of subcortical injury should be considered as one component of the complex AHT diagnostic process.
•Diagnosis of abusive head trauma (AHT) is significantly associated with subcortical brain injuries•Red flags for AHT (i.e. historical inaccuracies and traumatic extracranial injuries) are associated with subcortical injury•Clinical complications (i.e. cardiorespiratory compromise and seizures) are associated with subcortical injury
The International Union for Conservation of Nature's (IUCN) Red List is the global standard for quantifying extinction risk but assessing population reduction (criterion A) of wide‐ranging, ...long‐lived marine taxa remains difficult and controversial. We show how Bayesian state–space models (BSSM), coupled with expert knowledge at IUCN Red List workshops, can combine regional abundance data into indices of global population change. To illustrate our approach, we provide examples of the process to assess four circumglobal sharks with differing temporal and spatial data‐deficiency: Blue Shark (Prionace glauca), Shortfin Mako (Isurus oxyrinchus), Dusky Shark (Carcharhinus obscurus), and Great Hammerhead (Sphyrna mokarran). For each species, the BSSM provided global population change estimates over three generation lengths bounded by uncertainty levels in intuitive outputs, enabling informed decisions on the status of each species. Integrating similar analyses into future workshops would help conservation practitioners ensure robust, consistent, and transparent Red List assessments for other long‐lived, wide‐ranging species.
Physician diagnoses of abusive head trauma (AHT) have been criticized for circular reasoning and over-reliance on a “triad” of findings. Absent a gold standard, analyses that apply restrictive ...reference standards for AHT and non-AHT could serve to confirm or refute these criticisms.
To compare clinical presentations and injuries in patients with witnessed/admitted AHT vs. witnessed non-AHT, and with witnessed/admitted AHT vs. physician diagnosed AHT not witnessed/admitted. To measure the triad's AHT test performance in patients with witnessed/admitted AHT vs. witnessed non-AHT.
Acutely head injured patients <3 years hospitalized for intensive care across 18 sites between 2010 and 2021.
Secondary analyses of existing, combined, cross-sectional datasets. Probability values and odds ratios were used to identify and characterize differences. Test performance measures included sensitivity, specificity, and predictive values.
Compared to patients with witnessed non-AHT (n = 100), patients with witnessed/admitted AHT (n = 58) presented more frequently with respiratory compromise (OR 2.94, 95% CI: 1.50–5.75); prolonged encephalopathy (OR 5.23, 95% CI: 2.51–10.89); torso, ear, or neck bruising (OR 11.87, 95% CI: 4.48–31.48); bilateral subdural hemorrhages (OR 8.21, 95% CI: 3.94–17.13); diffuse brain hypoxia, ischemia, or swelling (OR 6.51, 95% CI: 3.06–13.02); and dense, extensive retinal hemorrhages (OR 7.59, 95% CI: 2.85–20.25). All differences were statistically significant (p ≤ .001). No significant differences were observed in patients with witnessed/admitted AHT (n = 58) vs. patients diagnosed with AHT not witnessed/admitted (n = 438). The triad demonstrated AHT specificity and positive predictive value ≥0.96.
The observed differences in patients with witnessed/admitted AHT vs. witnessed non-AHT substantiate prior reports. The complete absence of differences in patients with witnessed/admitted AHT vs. physician diagnosed AHT not witnessed/admitted supports an impression that physicians apply diagnostic reasoning informed by knowledge of previously reported injury patterns. Concern for abuse is justified in patients who present with “the triad.”
•Comparative analyses of patients with admitted/witnessed AHT vs. witnessed non-AHT confirm prior reports.•Analyses comparing patients with admitted/witnessed AHT vs. physician-diagnosed AHT serve to refute criticisms of physicians’ diagnostic reasoning.•The constellation of findings known as “the triad” is both highly specific and predictive of AHT.
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