Some snippets of long-term trend analysis from eBird data.

1. State of India’s Birds

2. 1.57 million
observations
0.66 million checklists
16,318 observers
1,333 species

3. State of India’s Birds
o Started in August 2018
o Multiple institutions
Ashoka Trust for Research in Ecology & the Environment
Bombay Natural History Society
Foundation for Ecological Security
National Centre for Biological Sciences
Nature Conservation Foundation
Salim Ali Centre for Ornithology and Natural History
Wetlands International – South Asia
Wildlife Institute of India
Worldwide Fund for Nature – India
o Based on long-term eBird data
o Population trend and/or range for 867
species
o Identifies species of conservation concern

4. o Long-term trend – % change in abundance (frequency of
reporting) in 2018 when compared to pre-2000 levels
o Current annual change – mean % annual change in abundance
(frequency of reporting) in the last 5 years, from 2014 to 2018
o Range size – occupied range size in the last 5 years, 2014 to 2018
3 indices of population status
100%
60%
40%
60%
20%

5. Frequencyof
Reporting
Effort
Standardize to checklist of
average effort
Variable effort across checklists

6. Frequencyof
Reporting
Month (Jan – Dec)
Frequencyof
Reporting
Effort
Standardize to average
month
Variation across months (Seasonality)
Standardize to checklist of
average effort

7. Frequencyof
Reporting
Month (Jan – Dec)
Frequencyof
Reporting
Effort
Clustering and variation across space
Average across spaceStandardize to checklist of
average effort
Standardize to average
month

8. Population trends relative to pre-2000

9. Population trends relative to pre-2000

10. Population trends relative to pre-2000

11. Population trends relative to pre-2000

12. Vultures

13. Indian Peafowl

14. Large-billed Crow

15. House Crow

16. Common Myna

17. Red-whiskered Bulbul

18. Feral Pigeon

19. Black Kite

20. Short-toed Snake-Eagle

21. Shikra

22. Ashy Drongo

23. Greater Racket-tailed Drongo

24. Black-rumped Flameback

25. Greater Flameback

26. Common Iora

27. Cotton Pygmy-Goose

28. Indian Spot-billed Duck

29. Glossy Ibis

30. Little Cormorant

31. Purple Sunbird

32. Purple-rumped Sunbird

33. Crimson-backed Sunbird

34. Orange Minivet

35. Small Minivet

36. Western Yellow Wagtail

37. White-browed Wagtail

38. Oriental Skylark

39. Pied Kingfisher

40. Plain Prinia

41. Rosy Starling

42. Yellow-browed Bulbul

43. White-throated Kingfisher

44. Eurasian Marsh-Harrier

45. White-browed Bulbul

46. Common Greenshank

47. Little Stint

48. Pacific Golden-Plover

49. Common Redshank

50. Common Sandpiper

51. Green Sandpiper

52. o Long-term trend – Generalized Linear Mixed-Effects Models with
binomial errors
o Current annual change – Generalized Linear Mixed-Effects
Models with binomial errors, annual change in past 5 years
o Range size – Simple Occupancy models
3 indices of population status
Category Rule: Long-term Rule: Current Category Rule
Data Deficient insufficient data insufficient data Data Deficient absent in data
Strong Decline decline > 50% decline > 2.7% Very Restricted range < 7,500 sq. km.
Moderate Decline decline > 25% decline > 1.1% Restricted range < 42,500 sq. km.
Strong Increase increase > 50% increase > 1.6% Very Large range > 1,000,000 sq. km.
Moderate Increase increase > 25% increase > 0.9% Large range > 250,000 sq. km.
Uncertain CI > 25% CI > 2% Moderate others
Stable others others
Range SizeTrend

53. Trends: Endemics

54. Trends: Migration

55. Trends: Waterbirds

56. Trends: Raptors

57. Strong Decline – Residents Important for Kerala
M
D

58. Strong Decline – Residents Important for Kerala
M
D

59. Strong Decline – Migrants Important for Kerala
M
D

60. Not Different from Stable (Long-term)
o Several species, especially resident generalists, stable
o Most migratory Anatidae uncertain

61. Indian Species of Conservation Concern (ISoCC)
o High Concern (require urgent
attention)
o Moderate Concern (species to watch)
o Low Concern
With the information from all three indices, and drawing
from IUCN status when trends were uncertain/data
deficient, species were categorized as:

62. Species of High Concern
M
D

63. Species of High Concern