Fisheries and aquaculture by wilaya — Algeria (2010-2022)

Algerian fisheries, wilaya by wilaya, 2010 to 2022. 942 observations across four indicators: the fleet in vessels, catch in tonnes, aquaculture output in tonnes, and fishermen in persons.

The fourteen coastal wilayas for fishing, twenty for aquaculture — which is also practised inland. And where the source publishes it, a breakdown by fleet segment: trawler, sardine boat, small-scale, tuna boat; or by crew category: skipper, engineer, deckhand.

The fleet grows from 4,191 vessels in 2010 to 6,044 in 2022, fishermen from 41,544 to 70,281. Catch falls from 85,451 tonnes in 2019 to 69,692 in 2020, then recovers to 98,188 in 2022.

Two perpendicular checks. Down the columns, the wilayas must sum to the published total; across the rows, the segments must sum to the wilaya's own total. The two rest on different axes: a reading shifted by one column breaks the second without touching the first. Thirty-two tables out of forty pass both.

Each column's nature is read from its header. One table sets a count, a percentage share and a growth rate side by side — three numbers that look alike and do not sum alike. Summing wilayas down a growth-rate column means nothing, and the check that did so rejected perfectly good tables. The derived columns are not published either: the buyer recomputes them exactly from the counts, and shipping them would add three columns not to be mistaken for a count.

What the layout demanded. One page carries several tables — page 17 of the 2021 edition holds three — and reading them as one made every wilaya appear twice while mixing tonnes with percentages. Tables are therefore split on their titles.

One naming trap is worth stating, because it does not show. The statistics office writes "Tiziouzou" as one word in some tables and "Tizi ouzou" in others. Aggregating on the label made two wilayas out of one: the 2018 national fleet went from 5,617 to 6,139 vessels, a jump with every appearance of growth. The aggregation key is the wilaya's official code, never its name — and it is by that code that this file joins our other wilaya-level products.

Revisions are flagged, not hidden. The 2019 booklet reports 447 vessels for Béjaïa; the decade retrospective and the 2020 edition report 432. Two editions against one: the revision wins. Where each edition speaks once, the later one prevails, and a column marks the 154 keys where editions disagree.

Units and source. Vessels, tonnes and persons, as published. 116 observations are confirmed by two distinct editions. Two-level tables — years on the first header row, fleet segments on the second — are not published: they announce four columns for twelve values, and every value would fall under a heading that is not its own.