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1.
  • Elmberg, Johan, 1960-, et al. (författare)
  • Passage patterns of seabirds in October at Cabo Carvoeiro Portugal, with special reference to the Balearic Shearwater Puffinus mauretanicus
  • 2016
  • Ingår i: Marine Ornithology. - 1018-3337 .- 2074-1235. ; 44:2, s. 151-156
  • Tidskriftsartikel (refereegranskat)abstract
    • Land-based counts of migrating seabirds remain essential to increase knowledge about their numbers and movements. To assess the value of Cabo Carvoeiro (Peniche, Portugal) as a monitoring site in the East Atlantic, we studied seabird species composition, passage patterns and flock size during mid-October 2014. During standardized counts, we observed nearly 8 000 seabirds of 17 species. The ratio of individuals passing in a southerly to southwesterly direction was >96% in all species, showing that genuine migrants were counted. The passage rate (birds/hour) was higher for Northern Gannets Morus bassanus than for any other species, by a factor of approximately 50 (morning mean 906/h, afternoon mean 1 153/h). The globally endangered Balearic Shearwaters Puffinus mauretanicus, Great Skuas Stercorarius skua and Pomarine Skuas S. pomarinus had passage rates of 10–25/h. Flock size distribution in the 11 most numerous species showed that most migrated singly or in groups of two. Flock size was larger in Balearic Shearwaters than in both Cory’s Calonectris borealis and Manx Shearwaters P. puffinus. Among skuas, flock size was larger in Pomarine than in Great Skuas. The passage rate of Manx Shearwaters was positively correlated with that of Northern Gannets, Great Skuas and Sandwich Terns Sterna sandvicensis. Northern Gannets showed a positive co-variation with Pomarine Skuas. Balearic and Sooty Shearwaters Ardenna griseus were the only species that did not show any significant co-variation with another species. Morning and afternoon passage rates did not differ significantly in any of the six most numerous species (Northern Gannets, Cory’s and Balearic Shearwaters, Great and Pomarine Skuas, and Sandwich Terns), or in Sooty Shearwaters (less numerous). Thus, the passage rates at Cabo Carvoeiro in October of Balearic Shearwaters and five other species were as high or higher than those reported from any other seawatch in Portugal, indicating the international value of seabird monitoring at Cabo Carvoeiro during the autumn migration.
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2.
  • Elmberg, Johan, 1960-, et al. (författare)
  • Seabird migration at Cabo Carvoeiro (Peniche, Portugal) in autumn 2015
  • 2020
  • Ingår i: Marine Ornithology. - 1018-3337 .- 2074-1235. ; 48:2, s. 231-244
  • Tidskriftsartikel (refereegranskat)abstract
    • Land-based counts at Cabo Carvoeiro (Peniche, Portugal), made between 15 August and 15 November 2015 (effort 90 d, 517 h), tallied302 469 birds, most of which (99.98%) were southbound. Although 65 species were observed, four species contributed to 91% of the total:207 608 Northern Gannet Morus bassanus, 32281 Cory’s Shearwater Calonectris borealis, 16086 Manx Shearwater Puffinus puffinus,and 15 222 Balearic Shearwater Puffinus mauretanicus. Passage as a whole increased throughout the period, mainly due to a gradualintensification of Northern Gannet migration. More than 67 000 southbound procellariforms of 12 species were recorded, as were 6183Stercorariidae of four species. Daily passage rates of species recorded on more than 68 d were positively correlated in 22 of 36 cases.For Northern Gannet and Mediterranean Gull Ichthyaetus melanocephalus, the proportion of adult birds increased steadily, outnumberingyounger birds. Extrapolation based on counted versus uncounted daylight hours suggests that at least 415000 Northern Gannets, 65000Cory’s Shearwaters, and 30000 Balearic Shearwaters passed south at Cabo Carvoeiro in autumn 2015. Clearly, a very large share of theglobal population of the endangered Balearic Shearwater can be monitored at Cabo Carvoeiro. Based on generally unidirectional passagepatterns, high species diversity, as well as high season totals and daily passage rates of several species, Cabo Carvoeiro is one of the mostpromising mainland sites in the eastern North Atlantic to monitor a wide range of seabirds.
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3.
  • Hentati-Sundberg, Jonas, et al. (författare)
  • FISH AND SEABIRD SPATIAL DISTRIBUTION AND ABUNDANCE AROUND THE LARGEST SEABIRD COLONY IN THE BALTIC SEA
  • 2018
  • Ingår i: Marine Ornithology. - 1018-3337 .- 2074-1235. ; 46:1, s. 61-68
  • Tidskriftsartikel (refereegranskat)abstract
    • We studied the at-sea distribution of two auks (Common Murre Uria aalge, Razorbill Alca torda), two gulls (Lesser Black-backed Gull Larus fuscus, Herring Gull Larus argentatus), and Great Cormorant Phalacrocorax carbo during the peak breeding season of 2014 around Stora Karlso, the main Baltic Sea seabird colony. Simultaneously, we quantified forage fish abundance and distribution using hydro-acoustics and pelagic trawling. The auks and gulls had a roughly similar distribution, foraging mainly about 40 km west-northwest from the colony. Great Cormorants were found only in inshore areas, close to the colony. Sprat Sprattus sprattus and herring Clupea harengus biomass was, respectively, 1.38 and 2.68 mt/km(2) averaged over the whole study area. These estimates represent a total biomass for small pelagic fish of 17 900 t in the 4 408 km(2) study area. The estimated prey consumption over the breeding season was 2 310 t for Common Murre and Razorbill combined. Thus, auks may have a non-negligible impact on their prey sources in the region. Common Murres foraged closer to the colony (median 36.3 km) than Razorbills (median 41.1 km), but we found no significant correlation between auk at-sea numbers and fish densities. We discuss how new technology can contribute to detailed monitoring of the interactions between seabirds and fish at different spatial and temporal scales, with the ultimate aim of providing a scientific basis for ecosystem-based management.
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4.
  • Hentati-Sundberg, Jonas, 1983-, et al. (författare)
  • The Karlsö Murre Lab methodology can stimulate innovative seabird research
  • 2012
  • Ingår i: Marine Ornithology. - 1018-3337 .- 2074-1235. ; 40, s. 11-16
  • Tidskriftsartikel (refereegranskat)abstract
    • Studies of seabirds have contributed substantially to theoretical and applied ecology, but practical limitations in the field and lack of knowledge of the life history of studied birds often constitute significant hurdles to progress in research. In the middle of the largest seabird colony in the Baltic Sea, on the island of Stora Karlsö, we have built an artificial breeding site for Common Murres Uria aalge. The Karlsö Murre Lab enables high-resolution studies with minimal disturbance of the breeding birds. It became operational, with the first recruitment of breeding murres, in 2009. Building materials and location were chosen to minimize environmental impact. The lab was constructed to allow future outfitting with a range of high-technology devices. Since most of the fledged chicks in the subcolony have been ringed over the last 10 years, this will enable recruitment and studies using advanced technology of birds with known life history. Hence, we will be able to perform seabird studies with a resolution that is impossible in a strictly natural environment. Better knowledge of links between seabirds and their environment facilitates the use of seabirds as indicators, which in turn can improve marine ecosystem-based management. 
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5.
  • Humphries, Grant R. W., et al. (författare)
  • BRIDGING THE GAP FROM STUDENT TO SENIOR SCIENTIST : RECOMMENDATIONS FOR ENGAGING EARLY-CAREER SCIENTISTS IN PROFESSIONAL BIOLOGICAL SOCIETIES
  • 2016
  • Ingår i: Marine Ornithology. - : AFRICAN SEABIRD GROUP. - 1018-3337 .- 2074-1235. ; 44:2, s. 157-166
  • Tidskriftsartikel (refereegranskat)abstract
    • Despite their long-standing and central role in the dissemination, promotion and defense of science. scientific societies currently face a unique combination of economic, social and technological changes. As a result, one of the most pressing challenges facing many societies is declining membership due to reduced recruitment and a failure to retain members, particularly early-career scientists (ECSs). To ensure that professional biological societies retain long-term viability and relevance, the recruitment and retention of ECSs needs to be a main priority. Here we propose a series of recommendations that we, a group of ECSs, believe will help professional societies better integrate and retain ECSs. We discuss each recommendation and detail its implementation using examples from our personal experiences in the global seabird research and management communities and from our collective experience as members of several professional societies. We believe these recommendations will not only help recruit and retain ECSs as society members, but will also directly benefit the organizations themselves.
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6.
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7.
  • Elmberg, Johan, et al. (författare)
  • Passage patterns of seabirds in October at Cabo Carvoeiro Portugal, with special reference to the Balearic Shearwater Puffinus mauretanicus
  • 2016
  • Ingår i: Marine Ornithology. - : Marine Ornithology. - 1018-3337. ; 44:2, s. 151-156
  • Tidskriftsartikel (refereegranskat)abstract
    • Land-based counts of migrating seabirds remain essential to increase knowledge about their numbers and movements. To assess the value of Cabo Carvoeiro (Peniche, Portugal) as a monitoring site in the East Atlantic, we studied seabird species composition, passage patterns and flock size during mid-October 2014. During standardized counts, we observed nearly 8 000 seabirds of 17 species. The ratio of individuals passing in a southerly to southwesterly direction was >96% in all species, showing that genuine migrants were counted. The passage rate (birds/hour) was higher for Northern Gannets Morus bassanus than for any other species, by a factor of approximately 50 (morning mean 906/h, afternoon mean 1 153/h). The globally endangered Balearic Shearwaters Puffinus mauretanicus, Great Skuas Stercorarius skua and Pomarine Skuas S. pomarinus had passage rates of 10–25/h. Flock size distribution in the 11 most numerous species showed that most migrated singly or in groups of two. Flock size was larger in Balearic Shearwaters than in both Cory’s Calonectris borealis and Manx Shearwaters P. puffinus. Among skuas, flock size was larger in Pomarine than in Great Skuas. The passage rate of Manx Shearwaters was positively correlated with that of Northern Gannets, Great Skuas and Sandwich Terns Sterna sandvicensis. Northern Gannets showed a positive co-variation with Pomarine Skuas. Balearic and Sooty Shearwaters Ardenna griseus were the only species that did not show any significant co-variation with another species. Morning and afternoon passage rates did not differ significantly in any of the six most numerous species (Northern Gannets, Cory’s and Balearic Shearwaters, Great and Pomarine Skuas, and Sandwich Terns), or in Sooty Shearwaters (less numerous). Thus, the passage rates at Cabo Carvoeiro in October of Balearic Shearwaters and five other species were as high or higher than those reported from any other seawatch in Portugal, indicating the international value of seabird monitoring at Cabo Carvoeiro during the autumn migration.
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8.
  • Elmberg, Johan, et al. (författare)
  • Seabird migration at Cabo Carvoeiro (Peniche, Portugal) in autumn 2015
  • 2024
  • Ingår i: Marine Ornithology. - : Marine Ornithology. - 1018-3337. ; 48:2, s. 231-244
  • Tidskriftsartikel (refereegranskat)abstract
    • Land-based counts at Cabo Carvoeiro (Peniche, Portugal), made between 15 August and 15 November 2015 (effort 90 d, 517 h), tallied 302469 birds, most of which (99.98%) were southbound. Although 65 species were observed, four species contributed to 91% of the total: 207 608 Northern Gannet Morus bassanus, 32 281 Cory's Shearwater Calonectris borealis, 16086 Manx Shearwater Puffinus puffinus, and 15 222 Balearic Shearwater Puffinus mauretanicus. Passage as a whole increased throughout the period, mainly due to a gradual intensification of Northern Gannet migration. More than 67000 southbound procellariforms of 12 species were recorded, as were 6183 Stercorariidae of four species. Daily passage rates of species recorded on more than 68 d were positively correlated in 22 of 36 cases. For Northern Gannet and Mediterranean Gull Ichthyaetus melanocephalus, the proportion of adult birds increased steadily, outnumbering younger birds. Extrapolation based on counted versus uncounted daylight hours suggests that at least 415 000 Northern Gannets, 65 000 Cory's Shearwaters, and 30000 Balearic Shearwaters passed south at Cabo Carvoeiro in autumn 2015. Clearly, a very large share of the global population of the endangered Balearic Shearwater can be monitored at Cabo Carvoeiro. Based on generally unidirectional passage patterns, high species diversity, as well as high season totals and daily passage rates of several species, Cabo Carvoeiro is one of the most promising mainland sites in the eastern North Atlantic to monitor a wide range of seabirds.
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  • Resultat 1-8 av 8

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