Falk, Knud

Møller, Søren

English

Roskilde Universitet

RoskildeUniversityField Report 2018Monitoring of the Peregrine Falcon population in South GreenlandFalk, Knud; Møller, SørenPublication date:2018Document VersionPublisher's PDF, also known as Version of recordCitation for published version (APA):Falk, K., & Møller, S. (2018). Field Report 2018: Monitoring of the Peregrine Falcon population in SouthGreenland.General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright ownersand it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.            • Users may download and print one copy of any publication from the public portal for the purpose of private study or research.            • You may not further distribute the material or use it for any profit-making activity or commercial gain.            • You may freely distribute the URL identifying the publication in the public portal.Take down policyIf you believe that this document breaches copyright please contact rucforsk@ruc.dk providing details, and we will remove access to thework immediately and investigate your claim.Download date: 02. Dec. 2021  FIELD REPORT 2018  Monitoring of the Peregrine Falcon population in South Greenland Knud Falk & Søren Møller  http://vandrefalk.dk/index_eng.shtml  Introduction For several decades, the Peregrine Falcon has served as an indicator species for the environmental effects of pesticides and other contaminants. Since 1981 we have conducted annual investigations of various aspects of Peregrine (Falco peregrinus tundrius) ecology and contaminant loads in the breed-ing population in South Greenland, and results include:  The identification of a slow, gradual de-crease in classical pesticide loads and as-sociated eggshell thinning effects.1–4  Increased burdens of new contaminants such as brominated flame retardants.4–6  Overall, the Peregrines in South Green-land have maintained a high productivity – 2.9 young/successful pair, or 1.8 young/occupied territory (1981-2018), alt-hough a worrying drop in productivity has been observed over the past few years. The high reproduction on average, so far, is to compensate for a high adult (female) turnover of around 25% (1985-2003).  Breeding phenology is gradually shifting towards earlier hatching dates, possibly as a consequence of changing climatic condi-tions.  Ring recoveries and Geolocator data (see below) reveal that the Peregrines migrate to Latin America – which is probably the source areas of the classical pesticides – whereas the more specific source areas of the new potentially harmful substances are more uncertain. Research objectives The overall project objective is to monitor and assess current and future impacts of environmental changes – chemical as well as climatic – and their effects on the Pere-grine Falcon population in Greenland. Hence, we aim to continue one of the long-est raptor monitoring efforts in the Arctic.    2 Methods and approaches The project is designed as a "lean" field programme to be conducted annually by two persons in 21-30 days. Small dinghies/Zodiacs are used to navigate the fjords between camp sites, from where the field team hikes to the selected standard monitoring Peregrine sites spanning the coastal and inland areas (see map, right). All field work is based on basic monitoring parameters sam-pled at selected sites every year in the core survey area and include:  Nest success and productivity - 3 parameters: proportion of occupied sites producing young, number of young per occupied and successful site. Data are compared to “crit-ical thresholds”.7  Breeding phenology: Date of first hatching in each nest – measured by standard aging catalogue and wing length8,9 or egg weight/measurements.  Samples o Addled eggs collected for contaminant analyses o Eggshell fragments from hatched eggs – for monitor-ing change in eggshell thickness as a proxy for DDT/DDE contamination1 o Moulted feathers for mercury and other metals.10 A special 2012-16 migration study applied miniature (1.9 g) archival light level data loggers11 ("geolocators" – GLs) providing daily locations almost year-round, and showed specific wintering locations and timing of migration for a few females. Since 2013 we also collect data on prey density by recording passerines on line transects along the hikes to/from Pere-grine nesting sites. We identify all species and age (adult or fledgling) and count all birds within 50 m horizontal distance from the observer path. This is a rough method providing an index for comparing changes and inter-year variability. Since 2017 we also install automatic cameras in active nests to monitor final breeding success and identify possible caus-es for failure.  Field work 2018 In 2018, field work was planned for two periods, but the June trip was abolished due to cancelled flights, so all field work was carried out 10 July – 2 August by Knud Falk and Søren Møller assisted by Lena Hansson, Marianne Lind and Per H. Pedersen. In 2018 the weather was very poor with delayed spring (snow on falcon nesting ledges around the time of egg-laying), and a rainy summer with several ‘very wet days’. A total of 14 site visits to the 12 core sites were con-ducted. Passerines were recorded at line transects covering a total of 26.3 km.  The standard Peregrine Falcon sample sites se-lected for long-term monitoring in South Green-land  Field work is based on a boat-based 2-3-person team navigating the fjords and hiking to each of the cliffs included in the monitoring programme  Egg mass and measurements helps determine hatching dates  Addled eggs are collected for contaminant anal-yses along with any shell fragments from hatched eggs for monitoring eggshell thickness.  3  Results Occupancy 11 out of 12 monitoring sites were occupied by at least one defensive adult Peregrine, and 3 pairs (27% of occupied sites) were breeding – which is as poor as the earlier record lows in 2015 and 2016 (Fig. 1). Breeding success The productivity was also among the record lows (Fig. 2). Figures 1 and 2 include the critical limits (red lines) as defined, based on literature re-views, in Monitoring Plan for the American Peregrine Falcon (USFWS)7 and it is clear that the Peregrine in South Greenland in most years have favourable reproduction, but with two marked dips over the study pe-riod – fluctuations that only long-term moni-toring can detect.  Over the coming years, more effort will be vested in identifying likely causes of the var-iability, including by field visits at the incuba-tion stage, nest cameras and recording weather parameters at the nest sites.  Breeding phenology Mean hatching date for first egg in the 3 clutches determined was 1st July, or 2 days earlier than the overall average (3 July) for 1981-2018, so despite poor spring weather the few successful pairs managed to breed early. Over the entire study period the over-all mean hatch date has shifted from 5 to 3 July (Fig. 3).  Samples Eggshell fragments, one dead, whole egg and feathers were collected at one nest each (table 1). All samples were transferred to Denmark with CITES permits. Nest cameras In 2017, automatic nest cameras were in-stalled in six successful nests, and the data harvested in 2018, providing several inter-esting results (Fig. 4):  All young in all six broods survived to at least 31 days of age, i.e. the cameras veri-fied the breeding success recorded earlier at the physical nest checks in 2017.  In spring 2018, three cameras revealed snow at nesting ledges in late May, i.e. at time of egg laying, verifying the challeng-ing weather conditions this year.   Figure 1: Nest success - proportion of occupied sites that produced young; the red line is the threshold where there “would be cause for concern in the short term” (USFWS) 7.   Figure 2: Annual productivity during the entire monitoring programme – measured as no of young/occupied site; the red line is the critical limit for productivity that “will initiate a special review” according to USFWS7.   Figure 3: Hatching date for first egg in each clutch (red dots), mean hatch date per year (black squares) and the long-term trend (line) in breeding phenology over the study period (note: preliminary data only).  4  Prey species: although the Snow Bunt-ing is rarely recorded at our transect walks, two male falcons appeared to be specialised on this prey type and brought home several adult buntings. In addition, a new prey species for our ar-ea was recorded: Arctic Hare (probably a leveret – Fig. 4). Monitoring of eggshell thickness The thickness of eggshell fragments from the hatched eggs have been measured and added to the long-term trend analysis (based on Falk et al. 2006), showing the continued improvement in shell thickness (Fig. 4) although it is yet not back to nor-mal. A more comprehensive reanalysis is now available.4 Migration studies by geolocators In 2012-15 geolocators (GL) were de-ployed at a total of eleven different adult breeding females. Until 2015, GLs from three birds had been recovered for analy-sis of movements in the au-tumn/winter/springs of 2012-15 and pre-liminary data shown in Field Reports 2016, 2017 as well as in Vorkamp et al.6 Unfortunately, expectations of capturing more GLs in 2018 were not met.    Figure 4: Examples of automatic nest camera results: last picture of full brood aged 31 days (upper); Snow Bunting brought to nest (mid-dle); Arctic Hare prey fed to chicks. 0.2000.2200.2400.2600.2800.3000.3200.3400.3600.3800.4001970 1980 1990 2000 2010Pre-DDT levelCritical thinning (17%) Figure 5: Eggshell thickness of fragments from hatched eggs in South Greenland 1981-2014 (circles) and central West Greenland 1972-1988 (triangles) as well as the joint trend line (samples from 2015-18 not measured yet). Blue horizontal line indicates average shell thickness before 1947 (= "normal"); red line shows 17% thin-ning threshold below which Peregrine populations have been shown to decline.12,13   5 Prey abundance A total of 233 passerines were recorded during the 26.3 km line, or 8.8 birds/km transect – which is the lowest since 2014 (Fig. 6). As usual, the most abun-dant species was the Wheatear, but this year both adults and juveniles were much less abundant than in the previous two warm summers. However, 2018 densities were not as low as 2013: In 2014-18 the density of passerines was more than a factor 4 to 8 higher than in 2013, confirming that 2013 was probably a very unusual year, as we sub-jectively noted then. In 2016 and 2017, the proportion of young birds ap-peared higher than other years.   Monitoring data application  Circumpolar falcon monitoring  The Conservation of Arctic Flora and Fauna (CAFF) programme under Arctic Council has initiated the Circumpolar Biodiversity Monitoring Programme (CBMP) and is preparing State of the Arctic Terres-trial Biodiversity Report planned for 2019. The Arctic falcons are key top predators included in the terres-trial monitoring plan14 and we have helped establish an Arctic Falcons Specialist Group (AFSG) to facili-tate cross-comparison of monitoring data from the circumpolar Arctic and try to harmonise basic sam-ple protocols for future population monitoring. Cur-rently, the first overview of long-term trends in the different sub-populations is being compiled and ana-lysed, including our data from South Greenland.   Figure 6: Relative density of passerines – main prey items – the past four year; observation conditions rarely allow aging of Redpolls which are excluded in the juv/adult bars   Passerines are the main prey of Peregrines in the study area where feathers of young, newly fledged Wheatears, Lapland Buntings and Redpolls are found on all successful Peregrine nesting ledges.  Fledged Wheatear broods of up to 5 chicks were the most widespread and conspicuous on all transects surveyed in 2014-17, but in 2018 they were relatively scarce.   6   Table 1. Site checks of the core ‘monitoring sites in 2018. Site no. Date No of eggs No of young Hatching (1. chick) Notes Samples 1 21 Jul 0 0  1 adult  2 22 Jul 0 0  1 adult   6 15 Jul 0 0 0 2 adults; 2017 camera collected  7 13 + 26 Jul  0 2 5 Jul 1 young disappeared between checks; camera collected and installed Feather samples 8 14 Jul  3 29 Jun 2 adults; young ringed  Eggshell fragments 23 17 + 30 Jul 0 0  2 adults; 2017 camera collected  29 23 Jul 0 0  2 adults, no breeding  32 15 Jul 0 0  1 adult, no breeding  42 16 Jul 0 0  1 adult; 2017 camera collected  61 11 Jul 1 3 29 Jun 2 adults, camera collected and installed Addled egg 63 23 + 30 Jul 0 0  2 adults; 2017 camera collected  66 8 Jun 0 0  No peregrines observed   Acknowledgements This year the project was supported by Aase og Jørgen Münters Fond.  Literature Cited 1. Falk, K., Møller, S. & Mattox, W. G. A long-term increase in eggshell thickness of Greenlandic Peregrine Falcons Falco peregrinus tundrius. Sci. Total Environ. 355, 127–134 (2006). 2. Vorkamp, K., Thomsen, M., Møller, S., Falk, K. & Sørensen, P. B. Persistent organochlorine compounds in peregrine falcon (Falco peregri-nus) eggs from South Greenland: levels and temporal changes between 1986 and 2003. Environ. Int. 35, 336–41 (2009). 3. Vorkamp, K. et al. Levels and trends of toxaphene and chlordane-related pesticides in peregrine falcon eggs from South Greenland. Sci. Total Environ. 468–469, 614–621 (2014). 4. Vorkamp, K. et al. New and updated time trends of persistent organic pollutants and their effects on eggs of peregrine falcons. (Aarhus University, DCE – Danish Centre for Environment and Energy, 2017). 5. Vorkamp, K. et al. Temporal Development of Brominated Flame Retardants in Peregrine Falcon (Falco peregrinus) Eggs from South Greenland (1986−2003). Environ. Sci. Technol. 39, 8199–8206 (2005). 6. Vorkamp, K., Falk, K., Moller, S., Rigét, F. & Sørensen, P. B. Regulated and unregulated halogenated flame retardants in peregrine falcon eggs from Greenland. Environ. Sci. Technol. 52, 474–483 (2018). 7. U.S. Fish and Wildlife Service. Monitoring Plan for the American Peregrine Falcon, a Species Recovered Under the Endangered Species Act. (U.S. Fish and Wildlife Service, Divisions of Endangered Species and Migratory Birds and State Programs, Pacific Region, 2003). 8. Clum, N., Harrity, P. & Weck, H. Aging young Peregrines. in Guide to Management of Peregrine Falcons at the Eyrie (eds. Cade, T. J., Enderson, J. H. & Linthcum, J.) 37–63 (The Peregrine Fund, 1996). 9. White, C. M., Clum, N. J., Cade, T. C. & Hunt, W. G. Peregrine Falcon (Falco peregrinus). in The Birds of North America, version 2.0 (eds. Poole, A. F. & Gill, F. B.) (Cornell Lab of Ornithology, 2002). 10. Dietz, R. et al. Time trends of mercury in feathers of West Greenland birds of prey during 1851-2003. Environ. Sci. Technol. 40, 5911–5916 (2006). 11. Bird migration tracking. Available at: http://birdtracker.co.uk/. (Accessed: 28th September 2018) 12. Falk, K. & Møller, S. Clutch Size Effects on Eggshell Thickness in the Peregrine Falcon and European Kestrel. Ornis Scand. 21, 265 (1990). 13. Peakall, D. B. & Kiff, L. F. DDE contamination in Peregrines and American Kestrels and its effect on reproduction. in Peregrine Falcon Populations: Their Management and Recovery (eds. Cade, T. J., Enderson, J. H., Thelander, C. G. & White, C. M.) 337–350 (The Pere-grine Fund, 1988). 14. Christensen, T. et al. Arctic Terrestrial Biodiversity Monitoring Plan. CAFF Monitoring Series Report Nr. 7. (CAFF International Secretariat, 2013).   Additional peer-reviewed publications from the project  Dietz, R. et al. The temporal and geographical mercury patterns in polar bears and birds of prey. in Fate of mercury in the Arctic (FOMA) (eds. Rysgaard, S. et al.) 33–41 (National Environmental Research Institute, 2004).  Falk, K. & Møller, S. Status of the Peregrine Falcon in South Greenland: Population Density and Reproduction. in Peregrine Falcon Popu-lations: Their Management and Recovery (eds. Cade, T. J., Enderson, J. H., Thelander, C. G. & White, C. M.) 37–43 (The Peregrine Fund, 1988).  Falk, K., Møller, S. & Burnham, W. A. The Peregrine Falcon Falco peregrinus in South Greenland: Nesting requirements, phenology and prey selection. Dansk Ornitol. Foren. Tidsskr. 80, 113–120 (1986).  Sørensen, P. B., Vorkamp, K., Thomsen, M., Falk, K. & Møller, S. Persistent organic Pollutants (POPs) in the Greenland environment - Long-term temporal changes and effects on eggs of a bird of prey. NERI Technical Report No. 509 (National Environmental Research Insti-tute, 2004).  Vorkamp, K. et al. Perfluoroalkyl substances (PFASs) and polychlorinated naphthalenes (PCNs) add to the chemical cocktail in peregrine falcon eggs. Sci. Total Environ. 648, 894–901 (2019).   7 Annex I: Ringing 2018   Ring no. Site Date Type1 Sex2 Age (days) Unit3 3R-0412 60008 2018-07-14 M F 14 D 4298329 60008 2018-07-14 M M 15 D 4298330 60008 2018-07-14 M M 14 D 3R-0413 60007 2018-07-26 M F 21 D 3R-0414 60007 2018-07-26 M F 21 D 1: M = ringing 2: M = Male; F = Female                vandrefalk.dk 

Field Report 2018:Monitoring of the Peregrine Falcon population in South Greenland

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Field Report 2018:Monitoring of the Peregrine Falcon population in South Greenland

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