36 research outputs found

    Diving Behavior, Habitat Associations, and Sensory Modalities for Prey Detection in Elephant Seals

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    I used video and movement data obtained from animal-borne video and data recorders (VDRs) and histological data obtained from vibrissal pads of elephant seals to address the questions: When, where, how, and on what prey do female southern elephant seals forage? Although the annual cycle of southern elephant seals for breeding, molting, and foraging is well known, there is little information about their foraging strategies, hunting tactics, habitat-associations and sensory biology at sea. I deployed VDRs and satellite telemeters on eight female southern elephant seals from Península Valdés, Argentina, during their two-month post-breeding migration. I identified three distinct dive types and their functions (foraging, resting and transiting) in the deep waters of the Patagonian continental slope and Argentine Basin. Compared to resting and transit dives, foraging dives were deeper and less linear with bursts of speed, steeper descent and ascent angles, longer two-dimensional and three-dimensional dive paths, and greater variation in speed, descent angle, and vertical head movements. The primary prey identified on video included herring smelt (Argentinidae) and myctophids (Myctophidae). Seals foraged at a mean maximum depth of 469 m with a mean water temperature of 3.7°C and mean salinity of 33.8 psu associated with Sub-Antarctic Mode Water, Antarctic Intermediate Water and Upper Circumpolar Deep Water. These habitat associations were similar to those for elephant seals from other colonies. Compared to foraging and transit dives, resting dives were longer in duration with shorter two-dimensional dive paths, lower stroking rates and speeds, and greater variation in pitch and roll angle during descent. Transit dives were shallower and more linear with higher swim speeds and stroking rates, shorter durations, shallower ascent angles, and farthest straight-line distances traveled. I provide evidence that elephant seal vibrissae have similar microstructure and innervation to other seals, adding to the growing body of evidence that species in the family Phocidae, and perhaps all pinnipeds, possess highly sensitive vibrissae that form a sensory system for prey detection and capture. In summary, female southern elephant seals from Península Valdés immediately depart the coast after breeding and travel to the continental slope while making shallow transit dives with little variation in easterly heading. Once beyond the continental shelf, they begin making deep foraging dives along the continental slope and Argentine Basin in cold water that arises from southern polar regions. While at sea for 75 days, they travel an average horizontal distance of 6,080 km and make 2,815 foraging dives. Their primary prey are small fish, some of which are bioluminescent, that they detect and capture in total darkness using vision and the tactile sensory system in their vibrissae. Between bouts of foraging dives, they make transit dives to new foraging areas or rest and probably sleep at an average maximum depth of 375 m. Of the 26 species of seals in the family Phocidae, southern elephant seals are the deepest diving and most pelagic, spending 10 months per year at sea and 89% of their time submerged while transiting, hunting and resting at depth

    2005 Wild Blueberry Project Reports

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    The 2005 edition of the Wild Blueberry Project Reports was prepared for the Wild Blueberry Commission of Maine and the Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include: 1. Evaluation of Emerging Disinfections Technologies for Wild Blueberry Processing 1A. Incorporation of wild blueberry puree into a soy-based burger and its effect on sensory and chemical properties of the broiled burgers. 2. Incorporation of wild blueberry puree into a soy-based burger and its effect on sensory and chemical properties of the broiled burgers 3. Wild blueberries and Arterial Functional Properties 4. Practical Microbial Control Approach and Antimicrobial Properties Study for Wild Blueberries 5. Wild Blueberries Reduce Risks for Cardiovascular Disease –No Report at this time, data is still under analysis. 6. Irrigation Water Use in Wild Blueberry Production 7. Control Tactics for Blueberry Pest Insects, 2005 8. Integrated Pest Management (IPM) strategies, 2005 9. Control Tactics for Blueberry Pest Insects, 2005 10. The Effect of Fungicides and Cultural Treatments on Monilinia Blight, Yield and Post-Harvest Disease in Wild Blueberries 11. Effect of Soil pH on Nutrient Uptake 12. Effect of Manganese on Growth and Yield of Wild Blueberry 13. Raising Foliar Nitrogen by Application of CoRoN 14. Effects of Summer Foliar Fertilization to Increase Branch Length and Flower Bud Formation in the Prune Year 15. Assessment of Hexazinone Alternatives for Weed Control in Wild Blueberries and Field Cover Program Base 16. Evaluation of Fall Applications of Tribenuron Methyl for Bunchberry Control in Wild Blueberries 17. Evaluation of spot treatments of Tribenuron Methyl for weed control in Wild Blueberries 18. Evaluation and Demonstration of Techniques for Filling in Bare Spots in Wild Blueberry Fields 19. Assessment of Evitol and Kerb for Sedge Control in Wild Blueberrie

    2011 Wild Blueberry Project Reports

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    The 2011 edition of the Wild Blueberry Project Reports was prepared for the Wild Blueberry Commission of Maine and the Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include: 1. Mechanisms through which wild blueberries affect functional characteristics of the arterial wall related to endothelial dysfunction in Spontaneously Hypertensive Rats 2. Do wild blueberries affect high blood lipids, high blood glucose and obesity as related to the Metabolic Syndrome? 3. Control tactics for blueberry pest insects, 2011 4. IPM strategies, 2011 5. Biology and ecology of pest insects, 2011 6. Biology and ecology of beneficial insects, 2011 7. Pesticide residues on lowbush blueberry, 2011 8. Maine wild blueberry –mummy berry research and extension 9. Valdensinia leaf spot – Education, control and research – 2011 10. Effect of soil pH on nutrient uptake 11. Evaluation of several growth regulators for stimulating lowbush blueberry rhizome production 12. Evaluation of the effects of Gypsum (CaSO4) on wild blueberry fruit Ca concentration 13. Fall application of tribenuron methyl for bunchberry control in wild blueberries, 2009-2011 – effects of fall versus spring pruning on cover and yield in the crop year (final report) 14. Wild Blueberry Extension Education Program in 2011 INPUT SYSTEMS STUDY: 15. Systems approach to improving the sustainability of wild blueberry production, Year 2 of a four-year study – experimental design 16. The effects of different agronomic practices on the composition and quality of wild blueberries 17. Systems approach to improving the sustainability of wild blueberry production, Year 2 of a four-year study, blueberry quality from the first harvest year 18. Food safety- Prevalence study of Escherichia coli O157:H7, Listeria monocytogenes and Salmonella spp. on lowbush blueberries (Vaccinium angustifolium) 19. Abundance of insect pest species and natural enemies in lowbush blueberry fields maintained under different management practices 20. Systems approach to improving the sustainability of wild blueberry production, Year 2 of a four-year study, disease management results 21. Systems approach to improving the sustainability of wild blueberry production, Year 2 of a four-year study, weed management results 22. Systems approach to improving sustainability of wild blueberry production, Year 1 of a four-year study, preliminary soil health and chemistry results 23. Management effects on the phosphorus chemistry of wild blueberry barrens soil 24. Systems approach to improving the sustainability of wild blueberry production, preliminary economic comparison 2010-2011 25. Transition to organic production Year 2: Evaluation of gypsum and bone char 26. The effect of field management, forest edge composition, and field location on insect-mediated ecosystem services (scavenging/predation) (ancillary study) 27. Pre-emergent combinations of herbicides for weed control in wild blueberry fields (ancillary study) 28. Systems approach to improving the sustainability of wild blueberry production – Ancillary land-leveling study, year 1 (ancillary study) 29. Effects of compost and mulch on soil health and soil nutrient dynamics in wild blueberry (ancillary study

    2006 Lowbush Blueberry Project Reports

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    The 2006 edition of the Lowbush Blueberry Project Reports was prepared for the Wild Blueberry Commission of Maine and the Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include: 1. Evaluation of Emerging Disinfection Technologies for Wild Blueberry Processing 2. Incorporation of wild blueberry puree into a soy-based burger and its effect on sensory and chemical properties of the broiled burgers 3. Infestation Detection using NIRS 4. Mechanism of Action through which Wild Blueberries affect Arterial Functional Properties in Normotensive and Spontaneously Hypertensive Rats 5. Practical Microbial Control Approach for Wild Blueberries and their Antimicrobial Property 6. Wild Blueberry Consumption and Risks for Cardiovascular Disease 7. Irrigation Water use in Wild Blueberry Production 8. Control Tactics for Blueberry Pest Insects & Program Base 9. Integrated Pest Management (IPM) Strategies 10. Biology and Ecology of Blueberry Insect Pests, 2006 11. Research on Wild Blueberry Diseases for 2006-2007 12. Effect of Soil pH on Nutrient Uptake 13. Effect of Manganese on Growth and Yield of Wild Blueberry 14. Effects of Summer Foliar Fertilization to Increase Branch Length and Flower Bud Formation in the Prune Year 15. Effects of Phosphite Foliar Fertilizers on disease control and fruit set of wild blueberry 16. Assessment of Hexazinone Alternatives for Weed Control in Wild Blueberries 17. Evaluation of Fall Applications of Tribenuron Methyl for Bunchberry Control in Wild Blueberries 18. Evaluation of spot treatments of Tribenuron Methyl, Ultim and Roundup for weed control in Wild Blueberries 19. Blueberry Extension Education Program 20. Cultural Weed Management Using p

    Precision gestational diabetes treatment: a systematic review and meta-analyses

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    Genotype-stratified treatment for monogenic insulin resistance: a systematic review

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