Changes in Adherence to the 24-Hour Movement Guidelines and Overweight and Obesity among Children in Northeastern Japan: A Longitudinal Study before and during the COVID-19 Pandemic

There are few studies comparing adherence to Canadian 24-hour Movement Guidelines (24-h MG) before and during the COVID-19 pandemic and exploring the pandemic’s effect on childhood obesity. This survey-based 2-year study investigated changes in obesity and adherence to the 24-h MG in children before and during the COVID-19 pandemic. Data were collected at two points in time: pre-COVID-19 (May 2019; T1; n = 247) and during-COVID-19 (May 2021; T2; n = 171). Participants were healthy elementary school children aged between 6–12 years in northeastern Japan. The questionnaire comprised items on physical activity, screen time, sleep duration, adherence to the 24-h MG, and anthropometric and demographic characteristics. Among all participants, a statistically significant difference (p < 0.001) between the average body mass index at T1 (M = 16.06 kg/m2, SD = 2.08 kg/m2) and T2 (M = 18.01 kg/m2, SD = 3.21 kg/m2) was observed, where 17.8% were overweight and obese at T1 and 24% at T2, and 10.9% adhered to all 24 h MG at T1 and 4.1% at T2. To prevent obesity in children during the COVID-19 pandemic, environmental changes should be evaluated and appropriate preventive measures taken, including pro-community health programs that encourage parent-children outdoor activities.

EVIDENCE OF MASS MORTALITY OF THE LONG-LIVED BIVALVE MERCENARIA STIMPSONI CAUSED BY A CATASTROPHIC TSUNAMI

ABSTRACT Tsunamis are huge disasters that can significantly damage benthic organisms and the sea-bottom environment in coastal areas. It is of great ecological importance to understand how benthic ecosystems respond to such destructive forces and how individual species are affected. Investigating the effect of such disasters on animals that are seldom caught alive is particularly difficult. Bivalve mollusks are especially suitable for investigating how a tsunami affects coastal benthic species because they preserve an environmental record in their shells that can be extended back in time by crossdating the records of multiple individuals. Here we studied dead shells of Mercenaria stimpsoni, a long-lived clam, and precisely determined the time of death by using nuclear bomb–induced radiocarbon (bomb-14C) and by counting annual growth increments. First, a quasi-continuous, regional bomb-14C record was created by analyzing the shells of 6 live-caught M. stimpsoni individuals. Then 27 dead shells collected from the seafloor of Funakoshi Bay were 14C-dated and analyzed. The results showed that the huge tsunami that struck northeastern Japan on 11 March 2011 caused mass mortality of this bivalve in Funakoshi Bay. Nine of the 27 clams died during the March 2011 tsunami, probably by starvation after burial by tsunami deposits or exposure above the seafloor as a result of sediment liquefaction during the earthquake. The dating method used in this study can help us understand how long-lived marine organisms with low population density are affected by huge natural disasters such as a tsunami.

Habitat Mapping for Human Well-Being: a tool for reducing risk in disaster-prone coastal environments and human communities

Coastal ecosystems consist of diverse habitats, such as reed beds, salt marshes, mangrove swamps, tidal flats, river deltas, seagrass fields, coral reefs, sandy/rocky-shore beaches and other habitats that harbour biodiversity. The Great East Japan Earthquake of March 2011 caused severe damage to one-third of the fishing communities along the Pacific Ocean of northeastern Japan. Coastal species, such as seagrasses, function as nursery areas for commercially important species. Coastal ecosystems provide natural infrastructure for the prevention and reduction of hazardous events, a process known as ecosystem-based disaster risk reduction (Eco-DRR). The preparation of topographic and thematic maps of coastal marine environments is essential to establish and visualise the concept of Eco-DRR. Experience gained following the Japanese earthquake, as well as examples from Indonesia and Thailand in the wake of 2004 Indian Ocean tsunami showed that Eco-DRR is an affordable and sustainable approach. Dissemination of habitat maps should be further promoted as a means to ‘Build Back Better’. To scale up and promote Eco-DRR, scientists must work in a transdisciplinary manner and engage with society through understanding the roles of ecosystems by monitoring and analysing, providing solutions and raising the awareness of community and policy makers, enabling them to better implement Eco-DRR.

Influence of normal tide and the Great Tsunami as recorded through hourly-resolution micro-analysis of a mussel shell

We report here hourly variations of Mg/Ca, Sr/Ca, and Ba/Ca ratios in a Mediterranean mussel shell (Mytilus galloprovincialis) collected at the Otsuchi bay, on the Pacific coast of northeastern Japan. This bivalve was living in the intertidal zone, where such organisms are known to form a daily or bidaily growth line comprised of abundant organic matter. Mg/Ca ratios of the inner surface of the outer shell layer, corresponding to the most recent date, show cyclic changes at 25–90 μm intervals, while no interpretable variations are observed in Sr/Ca and Ba/Ca ratios. High Mg/Ca ratios were probably established by (1) cessation of the external supply of Ca and organic layer forming when the shell is closed at low tide, and (2) the strong binding of Mg to the organic layer, but not of Sr and Ba. Immediately following the great tsunami induced by the 2011 Tohoku earthquake, Mg/Ca enrichment occurred, up to 10 times that of normal low tide, while apparent Ba/Ca enrichment was observed for only a few days following the event, therefore serving a proxy of the past tsunami. Following the tsunami, periodic peaks and troughs in Mg/Ca continued, perhaps due to a biological memory effect as an endogenous clock.

Behavioral response of wild mammals to pre-existing and artificial latrines of raccoon dogs in northeastern Japan

In this study, we reveal the behavior of raccoon dogs and other mammals on two types of latrines: already-existing latrines in the field and artificial latrines created from the feces of a captive individual. From September to November 2019, we used camera traps at already-known (eight sites), and artificial latrines (four sites), and recorded the mammalian species that visited, their behavior types, and the duration of time spent at the latrines. Our camera traps detected eight species visits, including raccoon dogs, masked palm civets, and rodents (Muridae). In raccoon dogs, sniffing, urination, defecation, and passing were observed, and the numbers of defecation and passing occurrences were significantly higher in the already-existing latrines. The duration time of the raccoon dogs was significantly longer at the artificial latrine; however, the time decreased as days elapsed. Masked palm civets frequently visited the artificial latrines, where the number of rubbings was significantly higher. The Muridae did not differ in their proportion of foraging behavior between the two latrine types, indicating that both were used as feeding sites without distinction. The results of this study indicate that raccoon dog latrines affect not only raccoon dogs but also other mammals.