McCracken SWT presentation

391 views

Published on

Presentation given to local Scottish Wildlife Trust Branch in March 2011

0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
391
On SlideShare
0
From Embeds
0
Number of Embeds
9
Actions
Shares
0
Downloads
0
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

McCracken SWT presentation

  1. 1. Chough stuff: developing chough conservation strategies Davy McCracken Senior Agricultural Ecologist Ayrshire Branch of Scottish Wildlife Trust Evening Meeting, SAC Auchincruive, 15 March 2011
  2. 2. Chough stuff: developing chough conservation strategies Scottish Chough Study GroupEric, Sue & Caitlin Bignal Pat Monaghan & Maria Bogdanova Jane Reid
  3. 3. Chough: distribution
  4. 4. Chough: distribution
  5. 5. Islay: mixture of land types Land types on Islay A: Upland heath, moorland and bog H: Coastal sedge B: Rocky coastal grassland and moorland, heath permanent pasture and grassland G: Sandy coastal C: Broken moorland ISLAY rushy fields and rough pasture and machair pasture F: Small farms and D: Blanket bogs, crofts and moorland lowland moorland edge and rough pasture E: Rotational pastures and mixed farmland mosaics
  6. 6. Islay: variety of bird species
  7. 7. Islay: variety of bird species Annex 1 birds on Islay LAND-TYPE A B C D E F G H W-Fronted Goose Golden Eagle Barnacle Goose Hen Harrier Corncrake Merlin Peregrine Red-Throated Diver Golden Plover Chough NESTING SUMMER WINTER
  8. 8. Chough on Islay: annual no.of breeding pairs 90 Number of breeding pairs 80 70 60 50 40 30 20 1980 1985 1990 1995 2000 2005 8
  9. 9. Detailed understanding through,e.g., students and Earthwatch 9
  10. 10. Colour-ringing has been crucialfor detailed understanding
  11. 11. Colour-ringing has been crucialfor detailed understanding
  12. 12. Chough annual cycle 12
  13. 13. Major factors affecting choughon Islay (1) Nest site availability (2) ‘Suitable’ feeding areas 13
  14. 14. Chough on Islay: increase in1980s 90 Number of breeding pairs 80 70 60 50 40 30 20 1980 1985 1990 1995 2000 2005 14
  15. 15. Provision of nest sites ingood feeding areas 15
  16. 16. Chough diet on IslayChough Diet on Islay J F M A M J J A S O N DSOIL Tipulidae Bibionidae Lepidoptera larvaeDUNG Diptera larvae Coleptera adults Coleoptera larvaeSURFACE-ACTIVEVEG Cereals Gagea 16
  17. 17. Dung insects important LIVESTOCK DUNG •Waves of invasion •Diptera (flies) •Coleoptera (beetles) •Nematodes & mites •Earthworms & soil inverts •Valuable resource IMPACT OF AVERMECTINS •Invertebrates in dung •Knock-on effects •Invertebrate communities? • Chough & other birds? 17
  18. 18. Dung insects important DAMAGE LIMITATION STRATEGY •Livestock need treatment •Assess potential/real risk •What is being used? •When and how often is treatment applied? •Ecology of wildlife of concern? •Manipulate •Method of application of treatment? •Timing of treatments? •Dung invertebrates need dung!! 18
  19. 19. Leatherjackets in grassland:annual mean number per field
  20. 20. Chough on Islay: annual no.of breeding pairs Assessed by full 90 census Number of breeding pairs 80 Predicted from population 70 dynamics model 60 50 40 30 20 1980 1985 1990 1995 2000 2005
  21. 21. Major factors affecting choughon Islay(3) Bottlenecks to recruitment - high nestling mortality - post-fledging survival 21
  22. 22. Focus on post-fledging survival • Observe the colour-ringed choughs • Follow their movements • Collect data on their feeding habits 22
  23. 23. Focus on post-fledging survival Movement from nest sites to sub- adult flock areas Map removed from slide before making presentation more widely available 23
  24. 24. Focus on post-fledging survival Highlighted importance of sand dune systems - 90% of foraging observations between April 06 and March 08 24
  25. 25. Focus on post-fledging survival Silage aftermaths also important - 10% of observations between June 06 and August 08 (but concentrated in June – August period) 25
  26. 26. Focus on post-fledging survival More diverse sward and structure Increased forb and seed resource Increased invertebrate resource Increased soil accessibility 26
  27. 27. Chough on Islay: annual firstyear survival probability Marked differences in survival since 2007 – last four years, i.e. including 2010 cohort, has been c. 10% or less
  28. 28. Chough on Islay: annual firstyear survival probability Major differences in July – September period in 2007- 2010. Large proportion of mortality occurring during that period
  29. 29. Chough on Islay: annual firstyear survival probability First year survival probability of each years young: Solid line = based on re-sightings of colour-ringed birds post-fledging Not simply a Dashed line = predictions based on weather and leatherjacket abundance food abundance issue. Predictions not reflecting reality since 2007– could grassland grazing &/or cutting regimes be preventing access to insect prey at key times?
  30. 30. What does the future hold? 30
  31. 31. Further informationRefereed papers: 6 in Journal of Animal Ecology and 1 in Journal ofApplied Ecology to-dateChough – the storyhttp://efncp.org/hnv-showcases/scottish-hebrides/chough/facts/Developing conservation strategies for thechough in Scotlandhttp://www.knowledgescotland.org/briefings.php?id=148 British Wildlife, 1997, vol. 8, issue 6, pages 373-383 31
  32. 32. 32

×