Differences in how raptors hunt and what they catch are correlated with size‐independent differences in length of the small intestine, the region of the digestive tract responsible for food absorption. The study examined the functional significance of these differences among ten raptor species. Dry matter apparent digestive efficiency was calculated for each species fed a diet of day‐old cockerels. For Falconiformes and Strigiformes, efficiencies varied between 75% and 82%, digestive efficiency being positively correlated with intestine length. Generalist species, with a wide prey spectrum and feeding on relatively easily caught prey and carrion, had long intestines and high digestive efficiencies. Raptors specializing on fast‐moving, avian prey had short intestines and reduced digestive efficiency. The Peregrine Falco peregrinus and the Common Buzzard Buteo buteo were used as examples of specialist and generalist feeders, respectively. Rabbit and pigeon were fed to both. Buzzards digested both diets more efficiently than Peregrines. Body‐mass changes were used to examine the nutritional value of the two diets to each species. Buzzards gained body‐mass when eating rabbit, Peregrines lost mass. Both species gained mass when feeding on pigeon. It seems that consideration of diet quality, not just quantity, is essential in understanding raptor food requirements. Generalist raptors have high efficiencies on several diets, specialists compensate for their reduced efficiency by eating food of high nutritional quality. Various aspects of prey quality are examined.
The study examines some aspects of gross morphology in Falconiformes and Strigiformes. It is hypothesized that, in predatory birds, hunting strategy might influence the relative size of skeletal musculature and length of the digestive tract. Falconiform species were categorized as either ‘attackers’ or ‘searchers’ depending on the degree to which active, powered pursuit is required for prey capture. Attacking species feed predominantly on avian prey, requiring extreme agility, speed and acceleration for prey capture. Searchers feed largely on relatively slow‐moving mammals and carrion. Comparisons between species of attackers and searchers showed that the former had heavier pectoral muscle mass, larger areas for flight muscle attachment and higher linearized wing loadings. Strigiformes had a pectoral muscle mass only half the size of that of attacking Falconiformes and had a correspondingly smaller sternum area. A skeletal body‐size measure was determined to enable calculation of intestine length independent of body‐size and shape differences. Attacking species have a small intestine which is 20–30% shorter than would be predicted on the basis of body‐size and 50% shorter than found in searchers of equivalent body‐size. Strigiformes that locate prey by active flight also have intestinal tracts shorter than expected. The likely effects of intestine length on digestive efficiency and food utilization are discussed and it is suggested that, in predatory birds, some species have evolved alimentary tracts that are shorter than necessary for maximum digestive efficiency in order to enhance prey capture.
Recent reports and studies document dramatic declines in a wide variety of wildlife species in Mongolia. The prime driver in these declines appears to be illegal and unsustainable hunting, both for local trade and consumption and for the international market. While data on these declines are sparse, comparisons of survey reports since the 1980s present evidence that some species may have declined by up to 90% in recent years. We outline the situation for eight major species of wildlife in Mongolia (saiga antelope, Mongolian gazelle, red deer, musk deer, argali, brown bear, Siberian marmot, and saker falcon). We then review the existing legal conditions and government efforts to control this situation, and suggest specific changes and actions that Mongolia should take to halt these dramatic declines in wildlife populations and avoid what may soon become an extinction crisis.
We analysed the Horizon 2020 project database, currently the European Union’s (EU) largest framework programme for research and innovation—nearly 80 billion euros available over 7 years (2014–2020), to estimate the amount and type of EU-supported biomedical and health research and funding distribution among EU member states and non-European countries. Out of 20,877 projects as of 14th January 2019, a total of 4865 projects were classified as human health related. Ninety-four countries/territories worldwide participated in at least one biomedical project. The EU-15 original member states showed the highest participation as project leaders/partners and for acquired funding. Strong unequal funding distribution and participation between EU-15 and the 13 newest members—with EU-15 receiving about 87% of funding and EU-13 only 3%—have been evidenced. For both EU-15 and EU-13 we detected about 20% of projects involving the public and private sectors, according to Horizon 2020 guidelines. The largest percentage of projects was in the areas of biotechnological research (28.28%) and “basic research” (26.95%); these two sectors together accounted for 46.99% of the total funding assigned (7.9 billion euros). Research in neurosciences and neurological diseases appeared to be an increasing study area. Neurological and mental diseases covered about 21% of projects. Epidemiological studies accounted for about 5% of the total projects and for 14% of funding. Strong correlations were shown by indicators of financial and scientific capacity to identify success rates in obtaining EU funding, making the gap between countries with strong and weak research infrastructures difficult to overcome. Electronic supplementary material The online version of this article (10.1007/s10654-020-00690-9) contains supplementary material, which is available to authorized users.
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