Baleen whale prey consumption based on high-resolution foraging measurements.

Baleen whales influence their ecosystems through immense prey consumption and nutrient recycling1-3. It is difficult to accurately gauge the magnitude of their current or historic ecosystem role without measuring feeding rates and prey consumed. To date, prey consumption of the largest species has been estimated using metabolic models3-9 based on extrapolations that lack empirical validation. Here, we used tags deployed on seven baleen whale (Mysticeti) species (n = 321 tag deployments) in conjunction with acoustic measurements of prey density to calculate prey consumption at daily to annual scales from the Atlantic, Pacific, and Southern Oceans. Our results suggest that previous studies3-9 have underestimated baleen whale prey consumption by threefold or more in some ecosystems. In the Southern Ocean alone, we calculate that pre-whaling populations of mysticetes annually consumed 430 million tonnes of Antarctic krill (Euphausia superba), twice the current estimated total biomass of E. superba10, and more than twice the global catch of marine fisheries today11. Larger whale populations may have supported higher productivity in large marine regions through enhanced nutrient recycling: our findings suggest mysticetes recycled 1.2 × 104 tonnes iron yr-1 in the Southern Ocean before whaling compared to 1.2 × 103 tonnes iron yr-1 recycled by whales today. The recovery of baleen whales and their nutrient recycling services2,3,7 could augment productivity and restore ecosystem function lost during 20th century whaling12,13.

Effect of In utero Exposure to Air Pollution on Adulthood Hospitalizations.

Empirical analyses have demonstrated that individuals exposed to severe air pollution in utero have worse health outcomes during childhood. However, there is little evidence on the long-term health impacts of air pollution exposure. The objective of this paper is to estimate the effect of in utero exposure to the Great London Smog of 1952 (GLS) on five health outcomes identified through a scoping review to be those most likely affected: respiratory, circulatory, neoplasms, mental health, and nervous system conditions. We use the GLS, an extreme air pollution event in December 1952, as a quasi-natural experiment to estimate the effect of exposure to air pollution in utero on adulthood health. Data from the UK Biobank is analysed for a cohort of participants born from December 1952 to July 1956. Differences in health outcomes between adults exposed and not exposed to the GLS due to their birth dates, born inside and outside London, were explored. Our primary focus is hospitalization events between 1997 and 2020 (corresponding to ages 40 to 69), as recorded in linked administrative data from the National Health Service (NHS). Specifically, the five primary outcomes are binary variables indicating that the individual had at least one hospitalization where the main cause of hospitalization is related to respiratory, circulatory, neoplasms, mental health, or nervous system conditions. The analytical sample comprised 36,281 individuals. A positive effect on adulthood hospitalizations due to respiratory conditions was observed. If exposed to the GLS in utero, the probability of at least one respiratory health-related hospitalization between 1997 and 2020 increased by 2.58 percentage points (95% CI 0.08, 4.30, p = 0.03), a 23% increase relative to the sample mean. Small effects were found for all other outcomes, suggesting that these conditions were not affected by the GLS. We do not find heterogeneous effects by sex or childhood socioeconomic status. This study found that a 5-day pollution exposure event while in utero significantly increased respiratory-related hospitalizations at ages 40 to 69 but had no impact on hospitalizations due to circulatory, neoplasms, mental health, and nervous system conditions.

A surplus no more? Variation in krill availability impacts reproductive rates of Antarctic baleen whales.

The krill surplus hypothesis of unlimited prey resources available for Antarctic predators due to commercial whaling in the 20th century has remained largely untested since the 1970s. Rapid warming of the Western Antarctic Peninsula (WAP) over the past 50 years has resulted in decreased seasonal ice cover and a reduction of krill. The latter is being exacerbated by a commercial krill fishery in the region. Despite this, humpback whale populations have increased but may be at a threshold for growth based on these human-induced changes. Understanding how climate-mediated variation in prey availability influences humpback whale population dynamics is critical for focused management and conservation actions. Using an 8-year dataset (2013-2020), we show that inter-annual humpback whale pregnancy rates, as determined from skin-blubber biopsy samples (n = 616), are positively correlated with krill availability and fluctuations in ice cover in the previous year. Pregnancy rates showed significant inter-annual variability, between 29% and 86%. Our results indicate that krill availability is in fact limiting and affecting reproductive rates, in contrast to the krill surplus hypothesis. This suggests that this population of humpback whales may be at a threshold for population growth due to prey limitations. As a result, continued warming and increased fishing along the WAP, which continue to reduce krill stocks, will likely impact this humpback whale population and other krill predators in the region. Humpback whales are sentinel species of ecosystem health, and changes in pregnancy rates can provide quantifiable signals of the impact of environmental change at the population level. Our findings must be considered paramount in developing new and more restrictive conservation and management plans for the Antarctic marine ecosystem and minimizing the negative impacts of human activities in the region.

Long-term health effects of a school construction program.

Non-communicable diseases (NCDs) disproportionately affect people in low- and middle-income countries (LMICs), yet context-specific evidence on policies that impact NCD risk factors is lacking. We estimate the impact of a massive Indonesian primary school expansion program in the 1970s on NCD risk factors in later life using data from two surveys with very large sample sizes. We find that in non-Java regions of Indonesia, the program led to significant increases in the likelihood of overweight and high waist circumference among women, but not among men. The increase for women can be partly explained by increased consumption of high-calorie packaged and take-away meals. We find no meaningful impacts on high blood pressure for either sex. Despite the increase in body weight, the program had a negligible impact on diabetes and cardiovascular disease diagnosis. It led to an improvement in women's self-reported health outcomes in their early-40s, but these benefits largely disappeared once they reached their mid-40s.

Cognitive activity at work and the risk of dementia.

Dementia prevalence is projected to rise steeply in coming decades, producing tremendous burdens on families, and health and social services. Motivated by the need for further robust evidence on modifiable risk factors, we investigate the relationship between cognitive activity at work and later-life dementia. Using data from the US Health and Retirement Study matched to the O*NET occupational database, we find that a one standard deviation increase in the cognitive activity associated with one's longest held occupation is associated with a 0.9 percentage point reduction in (predicted) dementia, or a 24% reduction relative to the mean. This relationship is consistently found across model specifications and robustness tests. When controlling for individual fixed-effects we find that the association between dementia and work cognitive activity increases with age. Overall, our results provide some evidence in support of the inclusion of cognitive activity at work as a recognized modifiable risk factor for dementia.

Scaling of maneuvering performance in baleen whales: larger whales outperform expectations.

Despite their enormous size, whales make their living as voracious predators. To catch their much smaller, more maneuverable prey, they have developed several unique locomotor strategies that require high energetic input, high mechanical power output and a surprising degree of agility. To better understand how body size affects maneuverability at the largest scale, we used bio-logging data, aerial photogrammetry and a high-throughput approach to quantify the maneuvering performance of seven species of free-swimming baleen whale. We found that as body size increases, absolute maneuvering performance decreases: larger whales use lower accelerations and perform slower pitch-changes, rolls and turns than smaller species. We also found that baleen whales exhibit positive allometry of maneuvering performance: relative to their body size, larger whales use higher accelerations, and perform faster pitch-changes, rolls and certain types of turns than smaller species. However, not all maneuvers were impacted by body size in the same way, and we found that larger whales behaviorally adjust for their decreased agility by using turns that they can perform more effectively. The positive allometry of maneuvering performance suggests that large whales have compensated for their increased body size by evolving more effective control surfaces and by preferentially selecting maneuvers that play to their strengths.

Whose mental health declines during economic downturns?

Prior research shows that economic downturns are associated with increases in mental illness. However, we know little about whose mental health is most negatively affected. Is it the young or old, men or women, employed or non-employed, rich or poor? Using an 18-year panel dataset of Australians, we contribute to this understanding by estimating the impact of changes in unemployment on mental health, separately by population subgroups. Our mental health measure captures psychological distress and emotional difficulties, which are often missed by infrequent event indicators such as suicides. We find that young women suffer most during economic downturns. Men and women of older ages are not significantly affected. The effects for young women are driven by those in insecure employment, and those from low socioeconomic backgrounds. Our results suggest that public health programs should emphasize the mental health of young women during economic downturns.

Flood disasters and health among the urban poor.

Billions of people live in urban poverty, with many forced to reside in disaster-prone areas. Research suggests that such disasters harm child nutrition and increase adult morbidity. However, little is known about impacts on mental health, particularly of people living in slums. In this paper we estimate the effects of flood disasters on the mental and physical health of poor adults and children in urban Indonesia. Our data come from the Indonesia Family Life Survey and new surveys of informal settlement residents. We find that urban poor populations experience increases in acute morbidities and depressive symptoms following floods, that the negative mental health effects last longer, and that the urban wealthy show no health effects from flood exposure. Further analysis suggests that worse economic outcomes may be partly responsible. Overall, the results provide a more nuanced understanding of the morbidities experienced by populations most vulnerable to increased disaster occurrence.

Who is resilient in a time of crisis? The importance of financial and non-financial resources.

Enhancing population resilience to adverse events is now a policy priority. Accordingly, there have been calls for more evidence on the determinants of resilience. We answer this call by identifying financial and non-financial resources associated with psychological resilience during the COVID-19 pandemic. Using longitudinal survey data, psychological resilience is measured by comparing distress reported pre-COVID-19 with distress reported during the outbreak and initial lockdown in April 2020. Methodologically, we compare differences in resilience and resources between people with identical gender, ethnicity, health, parenthood status, education, employment status, and region of residence (all measured pre-2020). We also provide estimates from within-household comparisons. Surprisingly, income, savings, and debt levels did not affect the likelihood of psychologically resilient outcomes. Cognitive ability, religiosity, and neighborhood social capital also had no protective effect. In contrast, we find robust evidence that non-cognitive skills, measured by self-efficacy, strongly protected against psychological distress. Self-efficacy also dampened the increase in distress caused by large earnings shocks. These findings support investments in non-cognitive skills that modify the damage-function from adverse events.

The link between health and economic preferences: Evidence from 22 OECD countries.

We study the link between health status and economic preferences using survey data from 22 Organisation for Economic Co-operation and Development (OECD) countries. We hypothesize that there is a relationship between poor health and the preferences that people hold, and therefore their choices and decisions. We find that individuals with a limiting health condition are more risk averse and less patient, and that this is true for physical and mental health conditions. The magnitudes of the health gap are approximately 60% and 70% of the gender gap in risk and time preferences, respectively. Importantly, the health gaps are large for males, females, young, old, school dropouts, degree holders, employed, nonemployed, rich, and poor. They also hold for countries with different levels of gross domestic product (GDP), inequality, social expenditure, and disease burden.

Scaling of swimming performance in baleen whales.

The scale dependence of locomotor factors has long been studied in comparative biomechanics, but remains poorly understood for animals at the upper extremes of body size. Rorqual baleen whales include the largest animals, but we lack basic kinematic data about their movements and behavior below the ocean surface. Here, we combined morphometrics from aerial drone photogrammetry, whale-borne inertial sensing tag data and hydrodynamic modeling to study the locomotion of five rorqual species. We quantified changes in tail oscillatory frequency and cruising speed for individual whales spanning a threefold variation in body length, corresponding to an order of magnitude variation in estimated body mass. Our results showed that oscillatory frequency decreases with body length (∝length-0.53) while cruising speed remains roughly invariant (∝length0.08) at 2 m s-1 We compared these measured results for oscillatory frequency against simplified models of an oscillating cantilever beam (∝length-1) and an optimized oscillating Strouhal vortex generator (∝length-1). The difference between our length-scaling exponent and the simplified models suggests that animals are often swimming non-optimally in order to feed or perform other routine behaviors. Cruising speed aligned more closely with an estimate of the optimal speed required to minimize the energetic cost of swimming (∝length0.07). Our results are among the first to elucidate the relationships between both oscillatory frequency and cruising speed and body size for free-swimming animals at the largest scale.

Temporal and Regional Variability in the Skin Microbiome of Humpback Whales along the Western Antarctic Peninsula.

The skin is the first line of defense between an animal and its environment, and disruptions in skin-associated microorganisms can be linked to an animal's health and nutritional state. To better understand the skin microbiome of large whales, high-throughput sequencing of partial small subunit rRNA genes was used to study the skin-associated bacteria of 89 seemingly healthy humpback whales (Megaptera novaeangliae) sampled along the Western Antarctic Peninsula (WAP) during early (2010) and late (2013) austral summers. Six core groups of bacteria were present in 93% or more of all humpback skin samples. A shift was observed in the average relative abundances of these core bacteria over time, with the emergence of four additional core groups of bacteria that corresponded to a decrease in water temperature, possibly caused by season- or foraging-related changes in skin biochemistry that influenced microbial growth, or other temporal factors. The skin microbiome differed between whales sampled at several regional locations along the WAP, suggesting that environmental factors or population may also influence the whale skin microbiome. Overall, the skin microbiome of humpback whales appears to provide insight into animal- and environment-related factors and may serve as a useful indicator for animal health or ecosystem alterations.IMPORTANCE The microbiomes of wild animals are currently understudied but may provide information about animal health and/or animal-environment interactions. In the largest sampling of any marine mammal microbiome, this study demonstrates conservation in the skin microbiome of 89 seemingly healthy humpback whales sampled in the Western Antarctic Peninsula, with shifts in the bacterial community composition related to temporal and regional variability. This study is important because it suggests that the skin microbiome of humpback whales could provide insight into animal nutritional or seasonal/environment-related factors, which are becoming increasingly important to recognize due to unprecedented rates of climate change and anthropogenic impact on ocean ecosystems.

Google Haul Out: Earth Observation Imagery and Digital Aerial Surveys in Coastal Wildlife Management and Abundance Estimation.

As the sampling frequency and resolution of Earth observation imagery increase, there are growing opportunities for novel applications in population monitoring. New methods are required to apply established analytical approaches to data collected from new observation platforms (e.g., satellites and unmanned aerial vehicles). Here, we present a method that estimates regional seasonal abundances for an understudied and growing population of gray seals (Halichoerus grypus) in southeastern Massachusetts, using opportunistic observations in Google Earth imagery. Abundance estimates are derived from digital aerial survey counts by adapting established correction-based analyses with telemetry behavioral observation to quantify survey biases. The result is a first regional understanding of gray seal abundance in the northeast US through opportunistic Earth observation imagery and repurposed animal telemetry data. As species observation data from Earth observation imagery become more ubiquitous, such methods provide a robust, adaptable, and cost-effective solution to monitoring animal colonies and understanding species abundances.

Passive acoustic monitoring of coastally associated Hawaiian spinner dolphins, Stenella longirostris, ground-truthed through visual surveys.

Effective decision making to protect coastally associated dolphins relies on monitoring the presence of animals in areas that are critical to their survival. Hawaiian spinner dolphins forage at night and rest during the day in shallow bays. Due to their predictable presence, they are targeted by dolphin-tourism. In this study, comparisons of presence were made between passive acoustic monitoring (PAM) and vessel-based visual surveys in Hawaiian spinner dolphin resting bays. DSG-Ocean passive acoustic recording devices were deployed in four bays along the Kona Coast of Hawai'i Island between January 8, 2011 and August 30, 2012. The devices sampled at 80 kHz, making 30-s recordings every four minutes. Overall, dolphins were acoustically detected on 37.1% to 89.6% of recording days depending on the bay. Vessel-based visual surveys overlapped with the PAM surveys on 202 days across the four bays. No significant differences were found between visual and acoustic detections suggesting acoustic surveys can be used as a proxy for visual surveys. Given the need to monitor dolphin presence across sites, PAM is the most suitable and efficient tool for monitoring long-term presence/absence. Concomitant photo-identification surveys are necessary to address changes in abundance over time.

Too Much of a Good Thing? Exploring the Impact of Wealth on Weight.

Obesity, like many health conditions, is more prevalent among the socioeconomically disadvantaged. In our data, very poor women are three times more likely to be obese and five times more likely to be severely obese than rich women. Despite this strong correlation, it remains unclear whether higher wealth causes lower obesity. In this paper, we use nationally representative panel data and exogenous wealth shocks (primarily inheritances and lottery wins) to shed light on this issue. Our estimates show that wealth improvements increase weight for women, but not men. This effect differs by initial wealth and weight-an average-sized wealth shock received by initially poor and obese women is estimated to increase weight by almost 10 lb. Importantly, for some females, the effects appear permanent. We also find that a change in diet is the most likely explanation for the weight gain. Overall, the results suggest that additional wealth may exacerbate rather than alleviate weight problems.

Childhood Obesity and Cognitive Achievement.

Obese children tend to perform worse academically than normal-weight children. If poor cognitive achievement is truly a consequence of childhood obesity, this relationship has significant policy implications. Therefore, an important question is to what extent can this correlation be explained by other factors that jointly determine obesity and cognitive achievement in childhood? To answer this question, we exploit a rich longitudinal dataset of Australian children, which is linked to national assessments in math and literacy. Using a range of estimators, we find that obesity and body mass index are negatively related to cognitive achievement for boys but not girls. This effect cannot be explained by sociodemographic factors, past cognitive achievement or unobserved time-invariant characteristics and is robust to different measures of adiposity. Given the enormous importance of early human capital development for future well-being and prosperity, this negative effect for boys is concerning and warrants further investigation.

The effect of mental health on employment: evidence from Australian panel data.

To what extent does poor mental health affect employment outcomes? Answering this question involves multiple technical difficulties: two-way causality between health and work, unobservable confounding factors and measurement error in survey measures of mental health. We attempt to overcome these difficulties by combining 10 waves of high-quality panel data with an instrumental variable model that allows for individual-level fixed effects. We focus on the extensive margin of employment, and we find evidence that a one-standard-deviation decline in mental health reduces employment by 30 percentage points. Further investigations suggest that this effect is predominantly a supply rather than a demand-side response and is larger for older than young workers.

Maternal perspectives on the use of probiotics in infants: a cross-sectional survey.

BACKGROUND: Probiotic products that may modify the intestinal microbiota are becoming increasingly available and known to consumers due to their potential to prevent or treat many pediatric health conditions. As scientific knowledge of the health benefits of probiotics increases, it is important to identify factors that may prevent their successful integration into patient care as well as to ensure effective translation of research findings. The aim of this study was to describe maternal perspectives on probiotics and their use in infants. METHODS: Mothers with a child aged two years or younger enrolled in the Alberta Pregnancy Outcomes and Nutrition (APrON) study were invited by email to complete a 29 item self-administered web-based questionnaire. RESULTS: A total of 413 mothers of the 1327 contacted completed the questionnaire. The majority (99.3%) of respondents had heard of probiotics and were aware that they contained live bacteria (87.0%); 89.3% had used a product containing probiotics themselves but only 50.8% had given one to their infant. Most mothers indicated they believed that probiotics were beneficial (73.1%) and none thought they were harmful. Over a third of mothers did not feel informed enough to make a decision on whether probiotics were safe to use in infants (36.6%). CONCLUSIONS: The study demonstrates that awareness and understanding of probiotics is high among mothers in Alberta, Canada. However, there is still uncertainty regarding the benefit of probiotics as well as safety in infants which could be important factors determining therapeutic use in the future. Further studies that demonstrate beneficial effects and safety of probiotics in healthy infants as well as targeted knowledge translation should help to address these potential concerns.

The Alberta Pregnancy Outcomes and Nutrition (APrON) cohort study: rationale and methods.

The Alberta Pregnancy Outcomes and Nutrition (APrON) study is an ongoing prospective cohort study that recruits pregnant women early in pregnancy and, as of 2012, is following up their infants to 3 years of age. It has currently enrolled approximately 5000 Canadians (2000 pregnant women, their offspring and many of their partners). The primary aims of the APrON study were to determine the relationships between maternal nutrient intake and status, before, during and after gestation, and (1) maternal mood; (2) birth and obstetric outcomes; and (3) infant neurodevelopment. We have collected comprehensive maternal nutrition, anthropometric, biological and mental health data at multiple points in the pregnancy and the post-partum period, as well as obstetrical, birth, health and neurodevelopmental outcomes of these pregnancies. The study continues to follow the infants through to 36 months of age. The current report describes the study design and methods, and findings of some pilot work. The APrON study is a significant resource with opportunities for collaboration.

The most effective strategy for recruiting a pregnancy cohort: a tale of two cities.

BACKGROUND: Pregnant women were recruited into the Alberta Pregnancy Outcomes and Nutrition (APrON) study in two cities in Alberta, Calgary and Edmonton. In Calgary, a larger proportion of women obtain obstetrical care from family physicians than from obstetricians; otherwise the cities have similar characteristics. Despite similarities of the cities, the recruitment success was very different. The purpose of this paper is to describe recruitment strategies, determine which were most successful and discuss reasons for the different success rates between the two cities. METHODS: Recruitment methods in both cities involved approaching pregnant women (< 27 weeks gestation) through the waiting rooms of physician offices, distributing posters and pamphlets, word of mouth, media, and the Internet. RESULTS: Between May 2009 and November 2010, 1,200 participants were recruited, 86% (1,028/1,200) from Calgary and 14% (172/1,200) from Edmonton, two cities with similar demographics. The most effective strategy overall involved face-to-face recruitment through clinics in physician and ultrasound offices with access to a large volume of women in early pregnancy. This method was most economical when clinic staff received an honorarium to discuss the study with patients and forward contact information to the research team. CONCLUSION: Recruiting a pregnancy cohort face-to-face through physician offices was the most effective method in both cities and a new critically important finding is that employing this method is only feasible in large volume maternity clinics. The proportion of family physicians providing antenatal and post-natal care may impact recruitment success and should be studied further.