Population Dynamics. Key to understanding and conservation of migratory birds

Transcription

1 Population Dynamics Key to understanding and conservation of migratory birds Franz Bairlein Institute of Avian Research Wilhelmshaven Photo: R. Nagel

2 Photo: R. Nagel

3 Photo: R. Nagel

4 Breeding birds Wadden Sea Migratory birds monitoring: YES understanding Mortality > Reproduction Koffijberg et al Blew et al. 2015

5 Population Dynamics of Wadden Sea migratory birds Breeding breeding success survival recruitment connectivity Non-breeding survival carry-overs Photo: R. Nagel

6 declining migratory bird populations residents/within- European migrants Why do they decline? What drives the decline? trans-saharan migrants Cuckoo Redstart Wood Wa Vickery et al. 2014

7 Common Redstart 100 Swiss, German and Dutch Redstart (avg. index) source: Leo Zwarts

8 Common Redstart rain Sahel Swiss, German and Dutch Redstart (avg. index) dry years: 12% decline wet years: 3% increase Sahel rain index (%) source: Leo Zwarts

9 60 50 Sedge Warbler UK Sedge Warbler annual survival annual survival (%) Peach et al ,5-1 -0,5 0 0,5 rainfall index in Sahel Sahel zone

10 Überlebensrate (%) annual survival Elsaß White Stork Alsace annual survival p<0.01 Bairlein 1993 % HPm Niederschlag im Sahel (mm/jahr) Sahel rain Niederschlag im Sahel (mm/jahr) Sahel zone

11 number of young per pair 3,0 2,5 2,0 1,5 1,0 0,5 0,0 White Stork DE breeding success White Stork carry-overs Bairlein & Henneberg rainfall in the Sahel Sahel zone

12 Wadden Sea Arctic breeding success (%) Bruterfolg (%) Ringelgans Brent Goose carry-overs body Körpergewicht mass Körpergewicht (g) (g) at departure beim Abflug (g) (nach Ebbinge 1989) Ebbinge 1989 capital breeders

13 stopover

14 iilegal killing and taking Figure 4 from Brochet et al. 2016, BCI

15 fueling 15 g 37 g 1g H 2 O/1g fat

16

17 1975 Precipitation Fink et al. 2009

18 long-term population trends in Danish birds (Heldbjerg & Fox 2008) 1975 trans-saharan migrants Fink et al. 2009

19 Vegetation Normalized Difference Vegetation Index (NDVI) - lack of rain - land use habitat loss Feb_d1_2005 Δ

20 Arrival (May) Barn Swallow Denmark (Szep & Møller 2004) carry-overs stopover conditions poor rich Normalized Difference Vegetation Index (NDVI) April_d2_2004

21 carry-overs American Redstart Smith & Moore 2003

22 Connectivity breeding breeding stopover stopover weak wintering strong wintering

23 The East-Atlantic Flyway breeding stopover Russian Arctic Pechora Delta Kanin / White Sea wintering Wadden Sea (courtesy Julia Stahl)

24 Connectivity new tracking technology GPS Logger ISS satellitetelemetry lightlevelgeolocation PinPoint GPS

25 Connectivity Grey Plover Photo: R. Nagel IfV Photo: R. Nagel

26 Connectivity Grey Plover Photo: R. Nagel female male AHY unknown sex Exo et al. 2016

27 Connectivity routes Montagu s Harrier stopover wintering Trierweiler et al. 2014

28 Connectivity Who dies where and when? autumn spring Marsh Harrier Osprey Montagu s Harrier Klaassen et al. 2014

29 Hewson et al Connectivity Common Cuckoo Who dies where and when? autumn survival spring

30 Connectivity - functional Sep Oct Nov Dec Jan Feb Mar Apr Montagu s Harrier linking tracking & ecology ( ground-truthing ) identifying requirements for - survival, - migration, - subsequent breeding - in-situ studies - remote data Ornithacris cavroisi Trierweiler et al

31 Structure of a population number of birds number of breeding birds age structure

32 age structure total nr of fledglings produced ( ) Common Tern Standardized breeding success Blue-footed Booby age female age (years) female age (years) S. Bouwhuis, IfV Kim et al. 2011

33 The conservation of migratory birds Understanding Population Dynamics Photo: R. Nagel

34 The conservation of migratory birds Understanding Population Dynamics annual cycle Photo: R. Nagel

35 The conservation of migratory birds Understanding Population Dynamics demography - breeding success - survival - recruitment - age structure annual cycle connectivity - spatio-temporal - functional carry-over Photo: R. Nagel

36 Population Dynamics of Wadden Sea migratory birds breeding tracking comparative approach Grey Plover NL NS SH DK Blew et al non-breeding demography monitoring e.g. juv/adult ratio colour-marking/resighting capture-recapture Photo: R. Nagel

37 Thank You! all best for the years to come! 10 th Wadden Sea Day Photo: R. Nagel