Determines which FAO major fishing area codes to restrict species to.
Resolution order is: the explicit fao_areas argument, then the
metadata.fishbase.fao_areas configuration key, then a default of
c(51, 57) — the Western and Eastern Indian Ocean.
Arguments
- conf
A configuration list as returned by
read_config().- fao_areas
Optional numeric vector of FAO major fishing area codes. If
NULL(default) the value is taken from configuration.
Details
Releases up to 4.5.0 hardcoded the area as 57, annotated "Western Indian
Ocean". That annotation was wrong. FAO Area 57 is the Eastern Indian
Ocean; the Western Indian Ocean — the water Kenya, Mozambique and Zanzibar
actually fish — is Area 51.
The default from 4.6.0 is c(51, 57) rather than 51 alone, because
FishBase's area assignments are incomplete at family level. Restricting to 51
by itself drops 19 taxon codes entirely, among them CLP — Clupeidae,
"Herrings, sardines nei" — whose 15 backbone species all carry area
assignments, 2 of which include 57 and none of which include 51. Dropping a
major Kenyan and Zanzibari fishery to a gap in reference metadata is the
wrong trade.
Because the filter is a disjunction, c(51, 57) is a strict superset of
pre-4.6.0 output: every species that resolved before still resolves. Pass
fao_areas = 57 to reproduce pre-4.6.0 output exactly.
Countries outside the Indian Ocean must set the key — Timor-Leste, for example, is FAO Area 71 (Pacific, Western Central).