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St. Lambert, Canada

Gavrilchuk K.,Laval University | Lesage V.,Maurice Lamontagne Institute | Lesage V.,Laval University | Ramp C.,Mingan Island Cetacean Study | And 4 more authors.
Marine Ecology Progress Series

Ecologically similar species may coexist when resource partitioning over time and space reduces interspecific competition. Understanding resource use within these species assemblages may help predict how species relative abundance might influence ecosystem functioning. In the Gulf of St. Lawrence, Canada, 4 species of rorqual whales (blue Balaenoptera musculus, fin B. physalus, minke B. acutorostrata and humpback Megaptera novaeangliae) coexist during the summer feeding period. They can be observed within hundreds of meters of one another, suggesting an overlap in ecological niches; yet fine-scale habitat use analyses suggest some resource partitioning. While major ecological changes have been observed in marine ecosystems, including the Gulf of St. Lawrence, we have little understanding of how the removal of predatory fish might cascade through ecosystems. Here, we take advantage of a 19 yr tissue collection subsequent to a fishery collapse (which occurred in 1992) to investigate trophic niche partitioning within a guild of rorqual whales following the loss of a key ecosystem component, groundfish. We analyzed stable isotope ratios for 626 rorqual individuals sampled between 1992 and 2010. Using Bayesian isotopic mixing models, we demonstrated that the 4 rorqual species segregated trophically by consuming different proportions of shared prey. An overall increase in δ15N values over the study period (post groundfish collapse), particularly for fin and humpback whales, suggested a progressive use of higher-trophic level prey, such as small pelagic fish, whereas the stability of blue whale diet over time confirmed their specialized feeding behaviour. This study provides the first longterm assessment of trophic ecology among rorqual populations on this Northwest Atlantic feeding ground, and evidence for differential resource use among large marine predators following ecosystem change. © 2014 Inter-Research. Source

Ramp C.,Mingan Island Cetacean Study | Ramp C.,University of Bremen | Berube M.,University of Stockholm | Palsboll P.,University of Stockholm | And 2 more authors.
Marine Ecology Progress Series

Sex-biased adult mortality is commonly observed in the animal kingdom. In mammals, a predominantly male-biased mortality is found in species with a polygynous mating system, while in monogamous taxa, female-biased mortality prevails. In the largest of all mammals, the Mysticeti, no sex-specific mortality has been found so far apart from that found in biased whaling data. We estimated sex-specific survival rates using an Akaike Information Criterion (AICc)-based model selection of 18 yr of mark-recapture data from a North Atlantic humpback whale feeding aggregation, the Gulf of St. Lawrence, Canada. We found a significantly higher survival rate for females (0.992; 95% CI 0.985-0.999) than for males (0.971; 0.943-0.985). Humpback whales are a typical polygynous species, with males competing intensively for mates while females bear the costs of pregnancy and lactation. However, the existing data did not allow us to test if differential costs of reproduction are causing the skew in mortality. We could not preclude stock-specific differences, such as contamination levels, migratory distances, and reproductive parameters (e.g. calving intervals, age at sexual maturity), and further data are needed to investigate the underlying reasons. © Inter-Research 2010. Source

Ramp C.,Mingan Island Cetacean Study | Ramp C.,University of Bremen | Hagen W.,University of Bremen | Palsboll P.,University of Stockholm | And 2 more authors.
Behavioral Ecology and Sociobiology

Analyses of social structures in baleen whales are rare, and so far, they are thought to consist of mostly short and unstable associations. We investigated the association patterns of individual humpback whales from a summer feeding aggregation in the Gulf of St. Lawrence from 1997 to 2005. Photo-identified animals were sexed using genetic methods and were grouped into five categories: juvenile males/females, mature males and lactating/non-lactating females. We calculated half-weight association indices within and between the groups and found that 45% of the observation showed single animals and another 45% small groups (two to three) consisting mainly of mature animals besides lactating females. Using permutation tests, we found evidence for long-term associations between mature males and non-lactating females as well as among non-lactating females. Standardised lagged association rates revealed that these male-female groups disassociated quickly over about 2 weeks, whereas associations increased again towards the beginning of the breeding season. Non-lactating females of similar age engaged in multi-seasonal stable pairs for up to six consecutive feeding seasons; no mature male-female association was observed in consecutive years. The females with the most stable and long-term associations also had the highest reproductive output. While the risk of predation could not explain these long-term bonds, feeding cooperation seemed the most plausible explanation for group forming behaviour during the summer months. © 2010 Springer-Verlag. Source

News Article | August 3, 2013
Site: gigaom.com

Healthcare CIOs must feel ill some days. They are under pressure by boards of directors and governments to keep costs down, while the medical establishment and government simultaneously foist more requirements to collect, store and analyze ever-increasing volumes of data. It’s a headache that no amount of aspirin will fix. Ironically, it may turn out that the CIOs’ latter problem can be a cure for the former. That is – given the right technology – insights gleaned from data soon will be the key to holding down healthcare expenditures while still improving patient care overall. Our current medical predicament is happening at a time when governments everywhere are hampered in how they can respond. In Europe, some nations have been forced to make major cuts to healthcare. According to the OECD Health Data 2012 report, compared with the prior year, the Irish government slashed its healthcare budget by 7.6 percent; in Greece, lawmakers hacked a whopping 13 percent. Even relatively stable (and generous) nations, such as Demark and Norway, have trimmed government health spending. In the United States, the Obama Administration has proposed $401 billion in budget reductions over 10 years to government-funded Medicare and Medicaid programs. While cutting subsidies, governments also are putting the industry under the gun to gather and store more information, adding to the compliance burden of IT. For example, as part of a movement toward evidence-based medicine, the Affordable Healthcare Act in the U.S., (better known as Obamacare), created the Patient-Centered Outcomes Research Institute, which will gather data on as many as 12 million patients over long periods to determine which treatments are the most efficacious for a given ailment. It will unquestionably produce an enormous amount of data – with a corresponding burden for all involved to handle it all. In addition to requirements from external authorities, CIOs also face daunting data demands from inside. For example, a standard EKG machine gathers about 1,000 data points per second. A two-dimensional mammogram requires 120 MB for each image, while a 3D MRI can hit 150 Mbytes and a 3D CT scan can top one gigabyte per image. All that information—both structured and unstructured data formats—must be stored and accessible for the life of the patient. Looming close on the horizon is vast patient genomic data and its promise for personalized medicine. In short, there is a building tidal wave of data coming straight at an already ailing healthcare industry. Yet, all this data may be the cure for the modern healthcare industry. In the United States, where healthcare already gobbles up 17.6 percent of the nation’s GDP, a recent McKinsey & Co. report suggests a shocking $600 billion is being misspent annually. The report suggests that a combination of data-driven, evidence-based medicine and modern tools to prod patients to lead healthier lives will go a long way to reducing those wasted billions of dollars, a process that’s already underway. For example, Eric Topol, an eminent cardiologist, has been widely profiled as an enthusiastic practitioner of mobile-health initiatives. He says that judicious application of smartphones and software can save patients, insurers and governments enormous amounts of money.  In one interview he showed an app available now that can deliver the results of a standard echocardiogram for patients – resulting in the savings of approximately $800 per test. With millions of echocardiograms conducted each year, the projected savings are enormous. M-health is already one of the healthiest parts of the booming smartphone app market. There are 97,000 m-health apps available today and the market is predicted to reach $26 billion in 2017. What’s common about these simple, inexpensive smartphone tools is that massive amounts of data is collected on anonymized patients that can be analyzed to benefit others without having to embark on major research projects. Through evidence-based medicine, overall patient care is improved at far less cost. I see four critical reasons to be optimistic that healthcare will get better, and soon, for individuals: First, we are seeing a global shift from “cookbook style” diagnosis – where symptoms are treated by a recipe approach – to evidence-based medicine, which applies data-centric methods to both diagnose and offer treatment. Second, there is a major effort industry-wide to collect as much medical data as possible, in any format, to analyze and accurately determine proper treatment for ailments. Third, with smartphones in hand, patients themselves are being empowered and learning to monitor personal health data themselves. And often at a fraction of the cost of the past. And finally, IT vendors have finally delivered a processor, networking, and database infrastructure that is capable of handling the data volumes and variety of information fast enough. Together these factors should help usher the healthcare industry into a new era of efficiency that still offers far better outcomes for patients.

Ramp C.,Mingan Island Cetacean Study | Ramp C.,University of St. Andrews | Delarue J.,Mingan Island Cetacean Study | Palsboll P.J.,University of Groningen | And 2 more authors.

Global warming poses particular challenges to migratory species, which face changes to the multiple environments occupied during migration. For many species, the timing of migration between summer and winter grounds and also within-season movements are crucial to maximise exploitation of temporarily abundant prey resources in feeding areas, themselves adapting to the warming planet. We investigated the temporal variation in the occurrence of fin (Balaenoptera physalus ) and humpback whales (Megaptera novaeangliae) in a North Atlantic summer feeding ground, the Gulf of St. Lawrence (Canada), from 1984 to 2010 using a long-term study of individually identifiable animals. These two sympatric species both shifted their date of arrival at a previously undocumented rate of more than 1day per year earlier over the study period thus maintaining the approximate 2-week difference in arrival of the two species and enabling the maintenance of temporal niche separation. However, the departure date of both species also shifted earlier but at different rates resulting in increasing temporal overlap over the study period indicating that this separation may be starting to erode. Our analysis revealed that the trend in arrival was strongly related to earlier ice break-up and rising sea surface temperature, likely triggering earlier primary production. The observed changes in phenology in response to ocean warming are a remarkable example of phenotypic plasticity and may partly explain how baleen whales were able to survive a number of changes in climate over the last several million years. However, it is questionable whether the observed rate of change in timing can be maintained. Substantial modification to the distribution or annual life cycle of these species might be required to keep up with the ongoing warming of the oceans. © 2015 Ramp et al. Source

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