The Experts below are selected from a list of 1131 Experts worldwide ranked by ideXlab platform
Verstraete H. - One of the best experts on this subject based on the ideXlab platform.
-
Monitoring van kustbroedvogels in de SBZ-V ‘Kustbroedvogels te Zeebrugge-Heist’ en de westelijke voorhaven van Zeebrugge tijdens het broedseizoen 2018
2019Co-Authors: Stienen E., Courtens W., Van De Walle, M., Vanermen N., Verstraete H.Abstract:This report describes the fluctuations in the numbers of breeding pairs in the Special Protected Area under the Bird Directive ‘Kustbroedvogels te Zeebrugge-Heist’ and in the adjacent western port of Zeebrugge during the period 1985-2017. Until recently, this was by far the most important breeding site for coastal breeders in Belgium and of high importance (> 1% of the biogeographic population) for the European tern populations as a whole. The conservation targets that were set in 2004 (being 22 ha of suitable nesting habitat without significant impact by land predators) for terns breeding in the Special Protected Area were never met since. The populations of the 3 tern species (Sandwich, Common and Little Tern) and of Black-headed Gulls breeding in the Special Protected Area have strongly declined after 2008 and the reproductive output has been extremely poor ever since. The decline is due to the presence of land predators, initially cats and rats, and from 2009 onwards also fox. The maximum number of breeding pairs amounted to respectively 4,067, 3,052 and 425 for Sandwich, Common and Little Tern,, but in 2016 these species no longer bred in the SPA. In 2017, fox was not present and the area again attracted Common Terns, although in lower numbers than before. In 2018, the SPA hosted 560 pairs of Common Tern, 23 pairs of Little Tern, 52 pairs of Black-headed Gull and 2 pairs of Mediterranean Gull, next to 60 pairs of Herring Gull and 354 pairs of Lesser Black-Backed Gull. Considering the SPA conservation targets, the nests of the latter two species were systematically cleared. About 60% of the tern population chose to breed in the areas that were electrically fenced to prevent fox predation and disturbance. Eventually almost all tern chicks outside the fence were predated by fox, leading to a poor breeding success of Common Terns of 0.2 fledglings per pair. Inside the electric fence breeding success was not measured, but seemed somewhat higher. Also, in the non-protected western part of the Zeebrugge port, breeding numbers are in strong decline due to fox disturbance and predation and deterioration of the habitat. This area used to host large numbers of Herring Gulls (max 2,433 pairs in 2010) and Lesser Black-Backed Gulls (max 4,760 pairs in 2011), but after 2013 both species strongly decreased in numbers as foxes frequented the breeding site. In 2018, 375 pairs of Herring Gull and 852 pairs of Lesser Black-Backed Gull bred in the western part of the port, all on fox-free rooftops or in electrically fenced areas. The total population in Zeebrugge (SBZ-V included) amounted to 472 and 1,390 pairs, respectively. After 2013 the numbers of Herring and Lesser Black-Backed Gull have increased elsewhere in Flanders and especially along the coast the number of breeding sites is rapidly growing. This suggests that part of the Zeebrugge colony has moved to both new and existing breeding sites. Indeed, recoveries of colour-ringed individuals revealed that there is a strong connection between Zeebrugge and other breeding sites along the Flemish coast. Other ringed Gulls moved to existing colonies in the north of France, the south of the Netherlands and the south-east of the UK. Colour ring sightings further suggest that the Gulls that colonised the SBZ-V most likely originate from the western part of the Zeebrugge port
-
Monitoring van kustbroedvogels in de SBZ-V ‘Kustbroedvogels te Zeebrugge-Heist’en de westelijke voorhaven van Zeebrugge tijdens het broedseizoen 2017
2018Co-Authors: Stienen E., Courtens W., Van De Walle, M., Vanermen N., Daelemans R., Verstraete H.Abstract:This report describes the fluctuations in the numbers of breeding pairs in the Special Protected Area under the Bird Directive ‘Kustbroedvogels te Zeebrugge‐Heist’ and in the adjacent western port of Zeebrugge during the period 1985‐2017. Until recently, this was by far the most important breeding site for coastal breeders in Belgium and of high importance for the European tern populations as a whole. The conservation targets that were set in 2004 (being 22 ha of suitable nesting habitat without significant impact by land predators) for terns breeding in the Special Protected Area were never met since.The populations of the 3 tern species (Sandwich, Common and Little Tern) and of Black‐headed Gulls breeding in the Special Protected Area have strongly declined after 2008 and the reproductive output was extremely poor. The decline is due to the presence of land predators, initially cats and rats, and from 2009 onwards also fox. The maximum number of breeding pairs amounted to 4,067, 3,052 and 425 for Sandwich, Common and Little Tern, respectively, but in 2016 these species no longer bred in the SPA. In 2017 fox was no longer present and the area again hosted 576 pairs of Common Tern, 21 pairs of Lesser Black‐backed Gull, 1 pair of Mediterranean Gull, 2 pairs of Kentish Plover , 12 pairs of Ringed Plover and 16 pairs of Oystercatcher. The SPA also attracted 114 pairs of Lesser Black‐backed and 44 pairs of Herring Gulls that were actively chased away in the nearby western part of the Zeebrugge port. Some of them developed into specialised predators of Common Tern leading to a reproductive output of only 0.1 fledged chick per pair.Also in the non‐protected western part of the Zeebrugge port, breeding numbers are in strong decline due to fox disturbance and predation, and loss of breeding grounds and deterioration of the habitat. Crested Lark, Northern Wheatear, Mediterranean Gull and Yellow‐legged Gull used to breed in small numbers, but these species were no longer present in 2016. This area used to host large numbers of Herring Gulls (max 2,433 pairs in 2010) and Lesser Black‐backed Gulls (max 4,760 pairs in 2011), but both species strongly decreased in numbers as fox frequented the breeding site after 2013. In 2017, 516 pairs of Herring Gull and 1.326 pairs of Lesser Black‐backed Gull bred in Zeebrugge, the majority (65.9%) on fox‐free rooftops. After 2013 the numbers of Herring and Lesser Black‐backed Gull have increased elsewhere in Flanders and especially along the coast the number of breeding sites is rapidly growing. This suggests that part of the Zeebrugge colony has moved to both new and existing breeding sites. Indeed, recoveries of colour‐ringed individuals revealed that there is a strong connection between Zeebrugge and other breeding sites along the Flemish coast. Other ringed Gulls originating from Zeebrugge moved to existing colonies in the north of France, the south of the Netherlands and the south‐east of the UK
-
Monitoring van kustbroedvogels in de SBZ-V ‘Kustbroedvogels te Zeebrugge-Heist’ en de westelijke voorhaven van Zeebrugge tijdens het broedseizoen 2014
2015Co-Authors: Stienen E.w.m., Courtens W., Van De Walle, M., Vanermen N., Verstraete H.Abstract:This report describes the fluctuations in the number of breeding pairs in the Special Protected Area under the Bird Directive ‘Kustbroedvogels te Zeebrugge-Heist’ and in the western port of Zeebrugge. These are by far the most important breeding sites for coastal breeders in Belgium and used to be of high importance for the biogeographical population as a whole. The quality of the breeding sites and the foraging areas is discussed and advice is given for a better management of the Special Protected Area.The populations of terns (Sandwich, Common and Little Tern) and Black-headed Gulls have decreased strongly since 2008 and the breeding success was insufficient for a stable population size. In Zeebrugge all 3 tern species used to exceed the threshold of 1% of their respective biogeographic population considerably. In 2014 none of the tern species reached this threshold. The decrease is due to persistent problems with land predators. Food availability seemed to play no role in this.Also some scarce species strongly declined in Zeebrugge. Crested Lark, Northern Wheatear, Mediterranean Gull and Yellow-legged Gull used to breed in the Zeebrugge port but in 2014 these species were no longer recorded. The numbers of Oystercatchers and Common Gull seem to have stabilised at a level much lower than before. Only the population of Common Ringed Plover is rather stable at about 8 pairs.Following a slight reduction in 2013, the populations of Herring and Lesser Black-Backed Gulls further and strongly declined in 2014. Both species used to exceed the 1% level (maxima of 1.2 and 2.8%, respectively for Herring and Lesser Black-Backed Gull), the number of Herring Gulls dropped to 0.2% of the total biogeographic population while that of Lesser Black-Backed Gull dropped to 0.6%. This decline is due to disturbance by foxes and a decreased availability of suitable nesting areas
Niall H. K. Burton - One of the best experts on this subject based on the ideXlab platform.
-
seabird wind farm interactions during the breeding season vary within and between years a case study of Lesser black backed Gull larus fuscus in the uk
Biological Conservation, 2015Co-Authors: Chris B Thaxter, Willem Bouten, Nigel A Clark, Greg J Conway, Viola H Rosssmith, Mark M Rehfisch, Niall H. K. BurtonAbstract:Abstract The marine environment is increasingly pressured from human activities, such as offshore renewable energy developments. Offshore wind farms may pose direct risks to seabirds at protected breeding sites. However, changes in food availability may influence foraging behaviour and habitat use during the breeding season or between years. Consequently, seabird–wind farm interactions, and risks posed to populations, may vary over longer time scales, but this has seldom been quantified. We used GPS-telemetry to study the movements of 25 Lesser Black-Backed Gulls from the Alde–Ore Special Protection Area (SPA), UK between 2010 and 2012, while birds were associated with their breeding colony. Variation in movements away from the colony, offshore, and in operational, consented and proposed Offshore Wind Farm Areas (“OWFAs”) was investigated: (1) between years and (2) across the breeding season, addressing: (3) sex-specific, (4) individual and (5) diurnal/nocturnal differences. The extent of overlaps with OWFAs varied between years, being greatest in 2010 (7/10 birds showing connectivity; area overlap: 6.2 ± 7.1%; time budget overlap: 4.6 ± 6.2%) and least in 2012. Marine habitats close to the colony were used before breeding. Birds spent little time offshore as incubation commenced, but offshore usage again peaked during the early chick-rearing period, corresponding with use of OWFAs. Individuals differed in their seasonal interactions with OWFAs between years, and males used OWFAs significantly more than females later in the breeding season. This study demonstrates the importance of tracking animals over longer periods, without which impact assessments may incorrectly estimate the magnitude of risks posed to protected populations.
-
Seabird–wind farm interactions during the breeding season vary within and between years: A case study of Lesser Black-Backed Gull Larus fuscus in the UK
Biological Conservation, 2015Co-Authors: Chris B Thaxter, Willem Bouten, Nigel A Clark, Greg J Conway, Viola H. Ross-smith, Mark M Rehfisch, Niall H. K. BurtonAbstract:Abstract The marine environment is increasingly pressured from human activities, such as offshore renewable energy developments. Offshore wind farms may pose direct risks to seabirds at protected breeding sites. However, changes in food availability may influence foraging behaviour and habitat use during the breeding season or between years. Consequently, seabird–wind farm interactions, and risks posed to populations, may vary over longer time scales, but this has seldom been quantified. We used GPS-telemetry to study the movements of 25 Lesser Black-Backed Gulls from the Alde–Ore Special Protection Area (SPA), UK between 2010 and 2012, while birds were associated with their breeding colony. Variation in movements away from the colony, offshore, and in operational, consented and proposed Offshore Wind Farm Areas (“OWFAs”) was investigated: (1) between years and (2) across the breeding season, addressing: (3) sex-specific, (4) individual and (5) diurnal/nocturnal differences. The extent of overlaps with OWFAs varied between years, being greatest in 2010 (7/10 birds showing connectivity; area overlap: 6.2 ± 7.1%; time budget overlap: 4.6 ± 6.2%) and least in 2012. Marine habitats close to the colony were used before breeding. Birds spent little time offshore as incubation commenced, but offshore usage again peaked during the early chick-rearing period, corresponding with use of OWFAs. Individuals differed in their seasonal interactions with OWFAs between years, and males used OWFAs significantly more than females later in the breeding season. This study demonstrates the importance of tracking animals over longer periods, without which impact assessments may incorrectly estimate the magnitude of risks posed to protected populations.
-
A trial of three harness attachment methods and their suitability for long-term use on Lesser Black-Backed Gulls and Great Skuas
Ringing & Migration, 2014Co-Authors: Chris B Thaxter, Eliza H K Leat, Jacquie A Clark, Nigel A Clark, Greg J Conway, Mike Marsh, Viola H. Ross-smith, Niall H. K. BurtonAbstract:Tracking devices are useful in studying the movement and behaviour of birds throughout the year. However, the effects of device attachment must be monitored for bird welfare and the scientific veracity of information gathered. We report on a trial of three different harness types (leg-loop, body and wing) for attaching GPS devices to Lesser Black-Backed Gulls Larus fuscus and of a leg-loop harness on Great Skuas Stercorarius skua. This trial evaluated the functionality of the device whilst deployed, harness retention and the effects of each harness on the birds. The leg-loop harness prevented the devices from charging, due to feathers overlapping their solar panels, and individuals of both species shed this attachment during the first breeding season. For Lesser Black-Backed Gull, devices functioned properly when attached using body and wing harnesses; foraging behaviour and territory attendance of birds were similar to the findings of other studies. Despite small sample sizes, annual adult survival rates...
Chris B Thaxter - One of the best experts on this subject based on the ideXlab platform.
-
Contrasting effects of GPS device and harness attachment on adult survival of Lesser Black‐backed Gulls Larus fuscus and Great Skuas Stercorarius skua
Ibis, 2016Co-Authors: Chris B Thaxter, Helen M Wade, Eliza H K Leat, Jacquie A Clark, Nigel A Clark, Greg J Conway, Sheila C Gear, Viola H. Ross-smith, Elizabeth A Masden, Mike MarshAbstract:Telemetry has become an important method for studying the biology and ecology of animals. However, the impact of tracking devices and their method of attachment on different species across multiple temporal scales has seldom been assessed. We compared the behavioural and demographic responses of two species of seabird, Lesser Black-Backed Gull Larus fuscus and Great Skua Stercorarius skua, to a GPS device attached using a crossover wing harness. We used telemetry information and monitoring of breeding colonies to compare birds equipped with a device and harness, and control birds without an attachment. We assessed whether tagged birds have lower short-term breeding productivity or lower longer term overwinter return rates (indicative of overwinter survival) than controls. For Great Skua, we also assessed whether territory attendance within the breeding season differed between tagged and control birds. As with previous studies on Lesser Black-Backed Gull, we found no short-term impacts on breeding productivity or long-term impacts on overwinter return rates. For Great Skua, there was no evidence for impacts of the device and harness on territory attendance or breeding productivity. However, as found by a previous study of Great Skuas using a different (body) harness design, there was strong evidence of reduced overwinter return rates. Consequently, a device attached using a wing harness was considered suitable for long-term deployment on Lesser Black-Backed Gulls, but not on Great Skuas. These findings will inform the planning of future tracking studies.
-
seabird wind farm interactions during the breeding season vary within and between years a case study of Lesser black backed Gull larus fuscus in the uk
Biological Conservation, 2015Co-Authors: Chris B Thaxter, Willem Bouten, Nigel A Clark, Greg J Conway, Viola H Rosssmith, Mark M Rehfisch, Niall H. K. BurtonAbstract:Abstract The marine environment is increasingly pressured from human activities, such as offshore renewable energy developments. Offshore wind farms may pose direct risks to seabirds at protected breeding sites. However, changes in food availability may influence foraging behaviour and habitat use during the breeding season or between years. Consequently, seabird–wind farm interactions, and risks posed to populations, may vary over longer time scales, but this has seldom been quantified. We used GPS-telemetry to study the movements of 25 Lesser Black-Backed Gulls from the Alde–Ore Special Protection Area (SPA), UK between 2010 and 2012, while birds were associated with their breeding colony. Variation in movements away from the colony, offshore, and in operational, consented and proposed Offshore Wind Farm Areas (“OWFAs”) was investigated: (1) between years and (2) across the breeding season, addressing: (3) sex-specific, (4) individual and (5) diurnal/nocturnal differences. The extent of overlaps with OWFAs varied between years, being greatest in 2010 (7/10 birds showing connectivity; area overlap: 6.2 ± 7.1%; time budget overlap: 4.6 ± 6.2%) and least in 2012. Marine habitats close to the colony were used before breeding. Birds spent little time offshore as incubation commenced, but offshore usage again peaked during the early chick-rearing period, corresponding with use of OWFAs. Individuals differed in their seasonal interactions with OWFAs between years, and males used OWFAs significantly more than females later in the breeding season. This study demonstrates the importance of tracking animals over longer periods, without which impact assessments may incorrectly estimate the magnitude of risks posed to protected populations.
-
Seabird–wind farm interactions during the breeding season vary within and between years: A case study of Lesser Black-Backed Gull Larus fuscus in the UK
Biological Conservation, 2015Co-Authors: Chris B Thaxter, Willem Bouten, Nigel A Clark, Greg J Conway, Viola H. Ross-smith, Mark M Rehfisch, Niall H. K. BurtonAbstract:Abstract The marine environment is increasingly pressured from human activities, such as offshore renewable energy developments. Offshore wind farms may pose direct risks to seabirds at protected breeding sites. However, changes in food availability may influence foraging behaviour and habitat use during the breeding season or between years. Consequently, seabird–wind farm interactions, and risks posed to populations, may vary over longer time scales, but this has seldom been quantified. We used GPS-telemetry to study the movements of 25 Lesser Black-Backed Gulls from the Alde–Ore Special Protection Area (SPA), UK between 2010 and 2012, while birds were associated with their breeding colony. Variation in movements away from the colony, offshore, and in operational, consented and proposed Offshore Wind Farm Areas (“OWFAs”) was investigated: (1) between years and (2) across the breeding season, addressing: (3) sex-specific, (4) individual and (5) diurnal/nocturnal differences. The extent of overlaps with OWFAs varied between years, being greatest in 2010 (7/10 birds showing connectivity; area overlap: 6.2 ± 7.1%; time budget overlap: 4.6 ± 6.2%) and least in 2012. Marine habitats close to the colony were used before breeding. Birds spent little time offshore as incubation commenced, but offshore usage again peaked during the early chick-rearing period, corresponding with use of OWFAs. Individuals differed in their seasonal interactions with OWFAs between years, and males used OWFAs significantly more than females later in the breeding season. This study demonstrates the importance of tracking animals over longer periods, without which impact assessments may incorrectly estimate the magnitude of risks posed to protected populations.
-
A trial of three harness attachment methods and their suitability for long-term use on Lesser Black-Backed Gulls and Great Skuas
Ringing & Migration, 2014Co-Authors: Chris B Thaxter, Eliza H K Leat, Jacquie A Clark, Nigel A Clark, Greg J Conway, Mike Marsh, Viola H. Ross-smith, Niall H. K. BurtonAbstract:Tracking devices are useful in studying the movement and behaviour of birds throughout the year. However, the effects of device attachment must be monitored for bird welfare and the scientific veracity of information gathered. We report on a trial of three different harness types (leg-loop, body and wing) for attaching GPS devices to Lesser Black-Backed Gulls Larus fuscus and of a leg-loop harness on Great Skuas Stercorarius skua. This trial evaluated the functionality of the device whilst deployed, harness retention and the effects of each harness on the birds. The leg-loop harness prevented the devices from charging, due to feathers overlapping their solar panels, and individuals of both species shed this attachment during the first breeding season. For Lesser Black-Backed Gull, devices functioned properly when attached using body and wing harnesses; foraging behaviour and territory attendance of birds were similar to the findings of other studies. Despite small sample sizes, annual adult survival rates...
Willem Bouten - One of the best experts on this subject based on the ideXlab platform.
-
Flap or soar? How a flight generalist responds to its aerial environment
Philosophical Transactions of the Royal Society B: Biological Sciences, 2016Co-Authors: Judy Shamoun-baranes, E. Emiel Van Loon, Christiaan Meijer, Willem Bouten, C J CamphuysenAbstract:The aerial environment is heterogeneous in space and time and directly influences the costs of animal flight. Volant animals can reduce these costs by using different flight modes, each with their own benefits and constraints. However, the extent to which animals alter their flight modes in response to environmental conditions has rarely been studied in the wild. To provide insight into how a flight generalist can reduce the energetic cost of movement, we studied flight behaviour in relation to the aerial environmental and landscape using hundreds of hours of global positioning system and triaxial acceleration measurements of the Lesser Black-Backed Gull (Larus fuscus). Individuals differed largely in the time spent in flight, which increased linearly with the time spent in flight at sea. In general, flapping was used more frequently than more energetically efficient soaring flight. The probability of soaring increased with increasing boundary layer height and time closer to midday, reflecting improved convective conditions supportive of thermal soaring. Other forms of soaring flight were also used, including fine-scale use of orographic lift. We explore the energetic consequences of behavioural adaptations to the aerial environment and underlying landscape and implications for individual energy budgets, foraging ecology and reproductive success.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'.
-
A network of feathered detectives.
2016Co-Authors: Joan Navarro, Willem Bouten, Francisco Ramírez, Isabel Afán, David Grémillet, Manuela G. ForeroAbstract:(a) Spatial distribution of reported illegal human waste dumps (blue dots; obtained from [10]) and three scavenger birds (yellow-legged Gull Larus michaellis, white stork Ciconia ciconia and black kite Milvus migrans) in the southern Spain, and (b) overall spatial distribution during breeding and wintering periods of four scavenger Gull species (European herring Gull Larus argentatus, Caspian Gull Larus cachinnans, Lesser Black-Backed Gull Larus fuscus and yellow-legged Gull) and the main cities (red points; population greater than one million inhabitants) across western Europe (in yellow). Spatial distribution (colour contours) was provided by BirdLife International and NatureServe (http://www.birdlife.org) and National Inventory of Biodiversity, Ministry of Agriculture, Food and Environment, Spanish Government. The map is made by ArcGIS 10.3 software (ESRI).
-
seabird wind farm interactions during the breeding season vary within and between years a case study of Lesser black backed Gull larus fuscus in the uk
Biological Conservation, 2015Co-Authors: Chris B Thaxter, Willem Bouten, Nigel A Clark, Greg J Conway, Viola H Rosssmith, Mark M Rehfisch, Niall H. K. BurtonAbstract:Abstract The marine environment is increasingly pressured from human activities, such as offshore renewable energy developments. Offshore wind farms may pose direct risks to seabirds at protected breeding sites. However, changes in food availability may influence foraging behaviour and habitat use during the breeding season or between years. Consequently, seabird–wind farm interactions, and risks posed to populations, may vary over longer time scales, but this has seldom been quantified. We used GPS-telemetry to study the movements of 25 Lesser Black-Backed Gulls from the Alde–Ore Special Protection Area (SPA), UK between 2010 and 2012, while birds were associated with their breeding colony. Variation in movements away from the colony, offshore, and in operational, consented and proposed Offshore Wind Farm Areas (“OWFAs”) was investigated: (1) between years and (2) across the breeding season, addressing: (3) sex-specific, (4) individual and (5) diurnal/nocturnal differences. The extent of overlaps with OWFAs varied between years, being greatest in 2010 (7/10 birds showing connectivity; area overlap: 6.2 ± 7.1%; time budget overlap: 4.6 ± 6.2%) and least in 2012. Marine habitats close to the colony were used before breeding. Birds spent little time offshore as incubation commenced, but offshore usage again peaked during the early chick-rearing period, corresponding with use of OWFAs. Individuals differed in their seasonal interactions with OWFAs between years, and males used OWFAs significantly more than females later in the breeding season. This study demonstrates the importance of tracking animals over longer periods, without which impact assessments may incorrectly estimate the magnitude of risks posed to protected populations.
-
Seabird–wind farm interactions during the breeding season vary within and between years: A case study of Lesser Black-Backed Gull Larus fuscus in the UK
Biological Conservation, 2015Co-Authors: Chris B Thaxter, Willem Bouten, Nigel A Clark, Greg J Conway, Viola H. Ross-smith, Mark M Rehfisch, Niall H. K. BurtonAbstract:Abstract The marine environment is increasingly pressured from human activities, such as offshore renewable energy developments. Offshore wind farms may pose direct risks to seabirds at protected breeding sites. However, changes in food availability may influence foraging behaviour and habitat use during the breeding season or between years. Consequently, seabird–wind farm interactions, and risks posed to populations, may vary over longer time scales, but this has seldom been quantified. We used GPS-telemetry to study the movements of 25 Lesser Black-Backed Gulls from the Alde–Ore Special Protection Area (SPA), UK between 2010 and 2012, while birds were associated with their breeding colony. Variation in movements away from the colony, offshore, and in operational, consented and proposed Offshore Wind Farm Areas (“OWFAs”) was investigated: (1) between years and (2) across the breeding season, addressing: (3) sex-specific, (4) individual and (5) diurnal/nocturnal differences. The extent of overlaps with OWFAs varied between years, being greatest in 2010 (7/10 birds showing connectivity; area overlap: 6.2 ± 7.1%; time budget overlap: 4.6 ± 6.2%) and least in 2012. Marine habitats close to the colony were used before breeding. Birds spent little time offshore as incubation commenced, but offshore usage again peaked during the early chick-rearing period, corresponding with use of OWFAs. Individuals differed in their seasonal interactions with OWFAs between years, and males used OWFAs significantly more than females later in the breeding season. This study demonstrates the importance of tracking animals over longer periods, without which impact assessments may incorrectly estimate the magnitude of risks posed to protected populations.
Greg J Conway - One of the best experts on this subject based on the ideXlab platform.
-
Contrasting effects of GPS device and harness attachment on adult survival of Lesser Black‐backed Gulls Larus fuscus and Great Skuas Stercorarius skua
Ibis, 2016Co-Authors: Chris B Thaxter, Helen M Wade, Eliza H K Leat, Jacquie A Clark, Nigel A Clark, Greg J Conway, Sheila C Gear, Viola H. Ross-smith, Elizabeth A Masden, Mike MarshAbstract:Telemetry has become an important method for studying the biology and ecology of animals. However, the impact of tracking devices and their method of attachment on different species across multiple temporal scales has seldom been assessed. We compared the behavioural and demographic responses of two species of seabird, Lesser Black-Backed Gull Larus fuscus and Great Skua Stercorarius skua, to a GPS device attached using a crossover wing harness. We used telemetry information and monitoring of breeding colonies to compare birds equipped with a device and harness, and control birds without an attachment. We assessed whether tagged birds have lower short-term breeding productivity or lower longer term overwinter return rates (indicative of overwinter survival) than controls. For Great Skua, we also assessed whether territory attendance within the breeding season differed between tagged and control birds. As with previous studies on Lesser Black-Backed Gull, we found no short-term impacts on breeding productivity or long-term impacts on overwinter return rates. For Great Skua, there was no evidence for impacts of the device and harness on territory attendance or breeding productivity. However, as found by a previous study of Great Skuas using a different (body) harness design, there was strong evidence of reduced overwinter return rates. Consequently, a device attached using a wing harness was considered suitable for long-term deployment on Lesser Black-Backed Gulls, but not on Great Skuas. These findings will inform the planning of future tracking studies.
-
seabird wind farm interactions during the breeding season vary within and between years a case study of Lesser black backed Gull larus fuscus in the uk
Biological Conservation, 2015Co-Authors: Chris B Thaxter, Willem Bouten, Nigel A Clark, Greg J Conway, Viola H Rosssmith, Mark M Rehfisch, Niall H. K. BurtonAbstract:Abstract The marine environment is increasingly pressured from human activities, such as offshore renewable energy developments. Offshore wind farms may pose direct risks to seabirds at protected breeding sites. However, changes in food availability may influence foraging behaviour and habitat use during the breeding season or between years. Consequently, seabird–wind farm interactions, and risks posed to populations, may vary over longer time scales, but this has seldom been quantified. We used GPS-telemetry to study the movements of 25 Lesser Black-Backed Gulls from the Alde–Ore Special Protection Area (SPA), UK between 2010 and 2012, while birds were associated with their breeding colony. Variation in movements away from the colony, offshore, and in operational, consented and proposed Offshore Wind Farm Areas (“OWFAs”) was investigated: (1) between years and (2) across the breeding season, addressing: (3) sex-specific, (4) individual and (5) diurnal/nocturnal differences. The extent of overlaps with OWFAs varied between years, being greatest in 2010 (7/10 birds showing connectivity; area overlap: 6.2 ± 7.1%; time budget overlap: 4.6 ± 6.2%) and least in 2012. Marine habitats close to the colony were used before breeding. Birds spent little time offshore as incubation commenced, but offshore usage again peaked during the early chick-rearing period, corresponding with use of OWFAs. Individuals differed in their seasonal interactions with OWFAs between years, and males used OWFAs significantly more than females later in the breeding season. This study demonstrates the importance of tracking animals over longer periods, without which impact assessments may incorrectly estimate the magnitude of risks posed to protected populations.
-
Seabird–wind farm interactions during the breeding season vary within and between years: A case study of Lesser Black-Backed Gull Larus fuscus in the UK
Biological Conservation, 2015Co-Authors: Chris B Thaxter, Willem Bouten, Nigel A Clark, Greg J Conway, Viola H. Ross-smith, Mark M Rehfisch, Niall H. K. BurtonAbstract:Abstract The marine environment is increasingly pressured from human activities, such as offshore renewable energy developments. Offshore wind farms may pose direct risks to seabirds at protected breeding sites. However, changes in food availability may influence foraging behaviour and habitat use during the breeding season or between years. Consequently, seabird–wind farm interactions, and risks posed to populations, may vary over longer time scales, but this has seldom been quantified. We used GPS-telemetry to study the movements of 25 Lesser Black-Backed Gulls from the Alde–Ore Special Protection Area (SPA), UK between 2010 and 2012, while birds were associated with their breeding colony. Variation in movements away from the colony, offshore, and in operational, consented and proposed Offshore Wind Farm Areas (“OWFAs”) was investigated: (1) between years and (2) across the breeding season, addressing: (3) sex-specific, (4) individual and (5) diurnal/nocturnal differences. The extent of overlaps with OWFAs varied between years, being greatest in 2010 (7/10 birds showing connectivity; area overlap: 6.2 ± 7.1%; time budget overlap: 4.6 ± 6.2%) and least in 2012. Marine habitats close to the colony were used before breeding. Birds spent little time offshore as incubation commenced, but offshore usage again peaked during the early chick-rearing period, corresponding with use of OWFAs. Individuals differed in their seasonal interactions with OWFAs between years, and males used OWFAs significantly more than females later in the breeding season. This study demonstrates the importance of tracking animals over longer periods, without which impact assessments may incorrectly estimate the magnitude of risks posed to protected populations.
-
A trial of three harness attachment methods and their suitability for long-term use on Lesser Black-Backed Gulls and Great Skuas
Ringing & Migration, 2014Co-Authors: Chris B Thaxter, Eliza H K Leat, Jacquie A Clark, Nigel A Clark, Greg J Conway, Mike Marsh, Viola H. Ross-smith, Niall H. K. BurtonAbstract:Tracking devices are useful in studying the movement and behaviour of birds throughout the year. However, the effects of device attachment must be monitored for bird welfare and the scientific veracity of information gathered. We report on a trial of three different harness types (leg-loop, body and wing) for attaching GPS devices to Lesser Black-Backed Gulls Larus fuscus and of a leg-loop harness on Great Skuas Stercorarius skua. This trial evaluated the functionality of the device whilst deployed, harness retention and the effects of each harness on the birds. The leg-loop harness prevented the devices from charging, due to feathers overlapping their solar panels, and individuals of both species shed this attachment during the first breeding season. For Lesser Black-Backed Gull, devices functioned properly when attached using body and wing harnesses; foraging behaviour and territory attendance of birds were similar to the findings of other studies. Despite small sample sizes, annual adult survival rates...