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107 results on '"Summers, R.W."'

1. The Movements of Icelandic Breeding Purple Sandpipers Calidris maritima Outside the Breeding Season.

Author

Summers, R.W., Hallgrimsson, G.T., Kalejta-Summers, B., Benediktsson, G.Ö., and Gunnarsson, H.

Abstract

Although a few ringing recoveries indicate that Icelandic breeding Purple Sandpipers Calidris maritima remain in Iceland through the year, there was the possibility that some spend the non-breeding season outside Iceland. To obtain a better understanding of their movements, 22 breeding adults (mainly males) were colour-ringed and tagged with geolocators in Arctic Tern Sterna paradisaea colonies on heathland adjacent to the coast of the Melrakkaslétta in northeast Iceland during 2019 and 2022. Counts, including searches for the colour-ringed birds, were also made on the coast beside the breeding areas through one non-breeding season (2019/20). Based on the recovery of 13 geolocators from males, 11 remained in northeast Iceland for the autumn moult, whilst two moved to northwest Iceland. By mid-winter, only five remained in northeast Iceland, and the rest wintered in the northwest and west of Iceland. Observations of colour-ringed birds confirmed that some remained close to their breeding area in autumn before dispersing to other parts of Iceland for winter. There was no evidence that Icelandic breeding birds left Iceland. Birds that wintered in the northwest and west of Iceland, returned to the northeast mainly during April. Counts during the non-breeding season along the shore adjacent to the breeding areas exceeded the number that could be accounted for by the local breeding population, indicating an influx of wintering birds from elsewhere. [ABSTRACT FROM AUTHOR]

Published
2024
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3. Ecological correlates of variable organ sizes and fat loads in the most northerly wintering shorebirds

Author

Ruthrauff, D.R., Dekinga, A., Gill, Jr., R.E., Summers, R.W., and Piersma, T.

Subjects
Shore birds -- Physiological aspects, Thermogenesis -- Research, Zoology and wildlife conservation
Abstract

Shorebirds at northern latitudes during the nonbreeding season typically carry relatively large lipid stores and exhibit an up-regulation of lean tissues associated with digestion and thermogenesis. Intraspecific variation in these tissues across sites primarily reflects differences in environmental conditions. Rock (Calidris ptilocnemis (Coues, 1873)) and Purple (Calidris maritima (Briinnich, 1764)) sandpipers are closely related species having the most northerly nonbreeding distributions among shorebirds, living at latitudes up to 61°N in Cook Inlet, Alaska, and up to ~71°N in northern Norway, respectively. Cook Inlet is the coldest known site used by nonbreeding shorebirds, and the region's mudflats annually experience extensive coverage of foraging sites by sea and shore-fast ice. Accordingly, Rock Sandpipers increase their fat stores to nearly 20% of body mass during winter. In contrast, Purple Sandpipers exploit predictably ice-free rocky intertidal foraging sites and maintain low ( Key words: energetics, lipid stores, Purple Sandpiper, Calidris maritima, Rock Sandpiper, Calidris ptilocnemis, storage strategies, temperature effects, thermogenesis. Les oiseaux de rivage qui passent la saison internuptiale a des latitudes septentrionales ont des reserves de graisse relativement grandes et presentent une regulation positive des tissus maigres associee a la digestion et la thermogenese. Des variations spatiales intraspecifiques dans ces tissus temoignent principalement de conditions du milieu differentes. Le becasseau des Aleoutiennes (Calidris ptilocnemis (Coues, 1873)) et le becasseau violet (Calidris maritima (Brunnich, 1764)) sont des especes etroitement apparentees qui, de tous les oiseaux de rivage, ont les aires de repartition internuptiales les plus septentrionales, ces dernieres pouvant aller jusqu'a 61°N dans la baie de Cook (Alaska) et jusqu'a ~71°N dans le nord de la Norvege, respectivement. La baie de Cook est l'endroit connu le plus froid utilise par des oiseaux de rivage en periode internuptiale, la glace marine et de rive recouvrant annuellement une bonne partie des lieux d'alimentation des battures de vase de la region. Les becasseaux des Aleoutiennes accroissent donc leurs reserves de graisse jusqu'a pres de 20 % de leur masse corporelle durant l'hiver. Les becasseaux violets, pour leur part, exploitent des sites d'alimentation intertidaux generalement exempts de glace, maintenant ainsi de faibles reserves de graisse ( Mots-cles : energetique, reserves de graisse, becasseau violet, Calidris maritima, becasseau des Aleoutiennes, Calidris ptilocnemis, strategies de constitution de reserves, effets de la temperature, thermogenese., Introduction Avian body composition has been extensively studied in numerous contexts, demonstrating that birds adaptively regulate fat and protein stores in conjunction with a diversity of life-history stages (Blem 1990; [...]

Published
2013
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4. Trichuris suis therapy in Crohn's disease

Author

Summers, R.W., Elliott, D.E., Urban, J.F., Jr., Thompson, R., and Weinstock, J.V.

Subjects
Helminths -- Health aspects, Helminths -- Research, Worms, Intestinal and parasitic -- Health aspects, Worms, Intestinal and parasitic -- Research, Crohn's disease -- Care and treatment, Crohn's disease -- Research, Health
Published
2005

5. Calcium supplements for the prevention of colorectal adenomas

Author

Baron, J.A., Beach, M., Mandel, J.S., Van Stolk, R.U., Haile, R.W., Sandler, R.S., Rothstein, R., Summers, R.W., Snover, D.C., Beck, G.J., Bond, J.H., and Greenberg, E.R.

Subjects
Colorectal cancer -- Prevention, Cancer -- Relapse, Calcium, Dietary -- Health aspects
Abstract

Calcium supplementation may prevent colorectal cancer, although the effect appears to be small. Researchers randomly assigned 832 people with a history of colorectal cancer to take 1200 milligrams of calcium or a placebo every day for up to four years. Colonoscopies were performed one and four years after the study began. Thirty-one percent of those taking calcium had a recurrence of their cancer, compared to 38% of those on placebo. This represents a 19% lower risk of cancer recurrence in those taking calcium. Those taking calcium who had a recurrence had fewer tumors.

Published
1999

7. Contrasting Trans-Atlantic Migratory Routes of Nearctic Purple SandpipersCalidris maritimaAssociated with Low Pressure Systems in Spring and Winter

Author

Summers, R.W., Boland, H., Colhoun, K., Elkins, N., Etheridge, B., Foster, S., Fox, J.W., Mackie, K., Quinn, L.R., Swann, R.L., Summers, R.W., Boland, H., Colhoun, K., Elkins, N., Etheridge, B., Foster, S., Fox, J.W., Mackie, K., Quinn, L.R., and Swann, R.L.

Abstract

Bird migration is generally scheduled to avoid other energetically expensive events in the annual cycle (e.g. moult) and seasons when survival can be difficult (e.g. northern winters). Purple Sandpipers winter at relatively high latitudes compared to other waders. It is suspected that the majority that winter in Britain and Ireland originate from Canada, but there is no primary evidence of their breeding grounds and migratory routes. These birds, characterised by their long bills, start to arrive in Britain and Ireland in late October/early November, after completing their post-nuptial moult at an unknown location. Fifty geolocators were attached to Purple Sandpipers in northern Scotland and southwest Ireland and we established for the first time their Canadian origin (Baffin Island and Devon Island), migration routes and post-nuptial moulting areas. Spring departure from Scotland and Ireland took place mainly in late May, followed by staging in Iceland and/or southwest Greenland before reaching the breeding grounds. Those that staged in Iceland departed earlier than those that flew directly to Greenland. Post-nuptial moulting areas were in southern Baffin Island, northern Quebec/Labrador (the Hudson Strait), and southwest Greenland. Migration from Baffin Island and Labrador took place during late October – early November, and during mid to late December from Greenland, usually in a single trans-Atlantic flight. Therefore, this migration was scheduled at a time when most other wader species are already on their wintering grounds. No birds staged in Iceland on the return trip. The flight from Baffin Island to Scotland and Ireland was accomplished in about 2.5 days at an average speed of about 1400 km per day. Freezing of coastal waters may be the reason for the eventual departure from the Hudson Strait. The more northerly route via Iceland, taken in spring by most birds, and the more southerly route in early winter were associated with seasonal shifts in the Atlantic

Published
2014

10. Ecological correlates of variable organ sizes and fat loads in the mostnortherly wintering shorebirds

Author

Ruthrauff, D.R., Dekinga, A., Gill, R.E., Summers, R.W., Piersma, T., Ruthrauff, D.R., Dekinga, A., Gill, R.E., Summers, R.W., and Piersma, T.

Abstract

Shorebirds at northern latitudes during the nonbreeding season typically carry relatively large lipid stores and exhibit an up-regulation of lean tissues associated with digestion and thermogenesis. Intraspecific variation in these tissues across sites primarily reflects differences in environmental conditions. Rock (Calidris ptilocnemis (Coues, 1873)) and Purple (Calidris maritima (Brünnich, 1764)) sandpipers are closely related species having the most northerly nonbreeding distributions among shorebirds, living at latitudes up to 61°N in Cook Inlet, Alaska, and up to ~71°N in northern Norway, respectively. Cook Inlet is the coldest known site used by nonbreeding shorebirds, and the region’s mudflats annually experience extensive coverage of foraging sites by sea and shore-fast ice. Accordingly, Rock Sandpipers increase their fat stores to nearly 20% of body mass during winter. In contrast, Purple Sandpipers exploit predictably ice-free rocky intertidal foraging sites and maintain low (<6.5%) fat stores. Rock Sandpipers increase the mass of lean tissues from fall to winter, including contour feathers, stomach, and liver components. They also have greater lean pectoralis and supracoracoideus muscle and liver and kidney tissues compared with Purple Sandpipers in winter. This demonstrates a combined emphasis on digestive processes and thermogenesis, whereas Purple Sandpipers primarily augment organs associated with digestive processes. The high winter fat loads and increased lean tissues of Rock Sandpipers in Cook Inlet reflect the region’s persistent cold and abundant but sporadically unavailable food resources.

Published
2013

37. Nest-site selection by crossbills Loxia spp. in ancient native pinewoods at Abernethy Forest, Strathspey, Highland: Birds preferred stands with a particular density of trees, perhaps to avoid predation, and they selected aspects sheltered from prevailing winds.

Author

Summers, R.W., Humphreys, E., Newell, M., and Donald, C.

Abstract

AimTo describe the nesting habitat and tree selection by crossbills in a restricted pinewood habitat in Scotland. MethodsScots Pines used by nesting crossbills were described and compared with randomly selected pines. Nest aspect was related to wind strength and direction. ResultsThe crossbills selected trees at a density of 50–60 trees/ha. Such stands may be sufficiently dense to provide cover, yet occur at a low enough density to minimize being visited by potential arboreal predators, such as Red Squirrels and Pine Martens. Crossbills tended to nest on lateral branches on the northeast side of crowns. Tree crown development was not asymmetric, so the birds may choose the northeast side to shelter from the prevailing southerly to westerly winds. ConclusionStands of pines at a low density need to be maintained for the benefit of crossbills. [ABSTRACT FROM PUBLISHER]

Published
2002
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38. Numbers, migration phenology and survival of Purple Sandpipers Calidris maritima at Gourdon, eastern Scotland.

Author

Summers, R.W., Nicoll, M., and Peach, W.

Abstract

Purple Sandpipers wintering on the Kincardine coast had a protracted autumn arrival (one-quarter and three-quarters of the birds arrived on 30 July and 21 October respectively, 83 days) but a faster spring departure (one-quarter and three-quarters departed on 9 April and 27 May respectively, 48 days). The long arrival period was partly due to differences in the migration phenology of the two main wintering populations: short-billed birds from Norway arrived before the long-billed birds, probably from Canada. There was a smaller difference in departure times of the two populations: short-billed birds left before the long-billed birds. Minimum annual survival was estimated from resightings of 92 marked birds. There was no evidence that survival differed between adults and first-years or between birds of different bill-size classes, which were of different sex and geographical origin. Minimum annual survival was estimated to be 79.5%(se = 2.8%). The similarity between the mortality rate (20.5%) and the percentage of first-year birds in populations of Purple Sandpipers probably reflects balanced population dynamics. [ABSTRACT FROM PUBLISHER]

Published
2001
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39. Stagnicola; sumassi

Author

Bryant Walker Collection|Summers, R.W., Bryant Walker Collection|Summers, R.W., Bryant Walker Collection|Summers, R.W., and Bryant Walker Collection|Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-080307%5DUMMZ-MOL-80307_C, http://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/080307/UMMZ-MOL-80307_C/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

40. Stagnicola; sumassi

Author

Bryant Walker Collection|Summers, R.W., Bryant Walker Collection|Summers, R.W., Bryant Walker Collection|Summers, R.W., and Bryant Walker Collection|Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-080307%5DUMMZ-MOL-80307_C, http://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/080307/UMMZ-MOL-80307_C/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

41. Stagnicola; sumassi

Author

Bryant Walker Collection|Summers, R.W., Bryant Walker Collection|Summers, R.W., Bryant Walker Collection|Summers, R.W., and Bryant Walker Collection|Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-080307%5DUMMZ-MOL-80307_A, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/080307/UMMZ-MOL-80307_A/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

42. Stagnicola; sumassi

Author

Bryant Walker Collection|Summers, R.W., Bryant Walker Collection|Summers, R.W., Bryant Walker Collection|Summers, R.W., and Bryant Walker Collection|Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-080307%5DUMMZ-MOL-80307_B, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/080307/UMMZ-MOL-80307_B/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

43. Stagnicola; sumassi

Author

Bryant Walker Collection|Summers, R.W., Bryant Walker Collection|Summers, R.W., Bryant Walker Collection|Summers, R.W., and Bryant Walker Collection|Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-080307%5DUMMZ-MOL-80307_M, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/080307/UMMZ-MOL-80307_M/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

44. Lymnaea; bulimoides

Author

Summers, R.W., Summers, R.W., Summers, R.W., and Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-073583%5DUMMZ-MOL-73583_M, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/073583/UMMZ-MOL-73583_M/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

45. Lymnaea; bulimoides

Author

Summers, R.W., Summers, R.W., Summers, R.W., and Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-073583%5DUMMZ-MOL-73583_B, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/073583/UMMZ-MOL-73583_B/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

46. Lymnaea; bulimoides

Author

Summers, R.W., Summers, R.W., Summers, R.W., and Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-073583%5DUMMZ-MOL-73583_A, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/073583/UMMZ-MOL-73583_A/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

47. Lymnaea; bulimoides

Author

Summers, R.W., Summers, R.W., Summers, R.W., and Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-073583%5DUMMZ-MOL-73583_C, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/073583/UMMZ-MOL-73583_C/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

48. Euphaedusa; lorraini

Author

Summers, R.W., Summers, R.W., Summers, R.W., and Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-154983%5DUMMZ-MOL-154978-155018, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/154983/UMMZ-MOL-154978-155018/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

49. Allogona; townsendiana

Author

Summers, R.W., Summers, R.W., Summers, R.W., and Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-103065%5DUMMZ-MOL-103026-103066, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/103065/UMMZ-MOL-103026-103066/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

50. Planorbella; trivolvis

Author

Summers, R.W., Summers, R.W., Summers, R.W., and Summers, R.W.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-084509%5DUMMZ-MOL-84488-84528, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/084509/UMMZ-MOL-84488-84528/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

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