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Weaver Wednesday 3 [255] - Range changes [18]: Southern Red Bishop

2017-05-03 (779)

gravit8 Weaver Wednesday 3: range changes in S Africa (species text)

Southern Red Bishop Euplectes orix

Southern Red Bishop, Range-change map between SABAP1 (1987-1991) and SABAP2 (2007-current).
Red, orange and yellow = cells with very large, large, and small relative decreases
Blue, dark green and light green = cells with very large, large and small relative increases.
Cells = quarter-degree grid cells; Only cells with at least 4 checklists in both SABAP1&2 shown. All cells had this species recorded in SABAP1 or in SABAP2 or in both (more about interpretation at Biodiversity Observations 7.62: 1-13).

Southern Red Bishop
Southern Red Bishop,
figure from Birdpix

Range changes in SA

Range change summary
More 4 lists 30 lists
increases n % n %
Decrease 431 29 144 23
Tiny change 427 29 215 36
Increase 642 43 253 41
Total 1500 100 612 100
In South Africa the Southern Red Bishop has more grid cells with increases in reporting rate than cells showing decreases, between SABAP1 (1987-1991) and SABAP2 (2007-).

The points below match the points on the map above.

Areas with very large increases include:
1. Gauteng, north-eastern Free State, and southern Mpumalanga.
2. Central and southern Free State.

Areas with very large decreases include:
3. Most of Limpopo Province.
4. Central North-west Province.

Many areas in South Africa show a checkered pattern, suggesting small changes (ie stable populations).

Range changes elsewhere

Exotic populations established in foreign countries, eg United Arab Emirates, Australia: Appendix of Dyer EE, Redding DW, Blackburn TM. 2017. The global avian invasions atlas, a database of alien bird distributions worldwide. Nature Scientific Data 4 no: 170041.