Here are some quick point on how the current status have been arrived at.
| Additional Amber Listing Criteria |
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Historical population decline during 1800–1995, but recovering; population size has more than doubled over last 25 years |
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Moderate (25-49%) decline in UK breeding population over last 25 years |
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Moderate (25-49%) contraction of UK breeding range over last 25 years |
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Species with unfavourable conservation status in Europe
(SPEC = Species of European Conservation Concern) |
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Five-year mean of 1-300 breeding pairs in UK |
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At least 50% of UK breeding population in 10 or fewer sites, but not rare breeders |
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At least 50% of UK non-breeding population in 10 or fewer sites |
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At least 20% of European breeding population in UK |
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At least 20% of NW European (wildfowl), East Atlantic Flyway (waders) or European (others) non-breeding populations in UK |