Table 1 Variables considered in the BRT model.

Only variables included in the model are shown.

VariableDescriptionSupport
Indirect fishing pressures
  ln coastal populationNumber of people living in urban and rural areas
within 100 km of the nation’s coastline as of 2011
Large coastal populations may drive unsustainable
fishing practices (30)
  ln marine protein consumptionMarine fish food supply, g capita−1 day−1The reliance on marine fish products for dietary
protein and economic stability (42)
Direct fishing pressures
  ln chondrichthyan landingsTotal metric tons summed for all Aquatic Sciences
and Fisheries Information System species of
sharks, rays, and chimaeras. Total of 146
species-specific and 23 aggregate not elsewhere
indicated categories
Shark, ray, and chimaera products are of high
economic value (59); thus, sawfishes that are
caught opportunistically would have high
economic return (28)
  ln gear-specific marine fisheries landingsTotal metric tons summed for catches with
bottom trawls, gillnets, otter trawls, shrimp trawls,
small-scale gillnets, small-scale longlines,
small-scale trammel nets, and trammel nets
Sawfishes have high catchability in specific fishing
gears (53)
  ln fishing effortFishing effort (kW) for artisanal and subsistence
sectors from the EEZ of each nation
Sawfishes have high catchability in small-scale,
in-shore fisheries (53)
Management capacity
  World Governance IndexOn the basis of the control of corruption
government effectiveness, political stability, rule
of law, regulatory quality, and voice and
accountability
Governance is required for effective and
sustainable fisheries management (60)
  ln Gross Domestic ProductMeasured in million USDNations with high income and high development
status have better fisheries management than
low-income countries (60, 61)
  Human Development IndexMeasures life expectancy, education, and Gross
National Income
Nations with high income and high development
status have better fisheries management than
low-income countries (60, 61)
Ecological carrying capacity
  ln continental shelf areaMeasured as the area found within the distribution
maps for each species clipped to the maximum
depth of each reported species (km2)
Larger habitats can potentially support larger
sawfish populations (62)
  ln marine primary productivityChlorophyll a per nation, mg m−3Marine primary productivity linked to diversifying
food webs in marine habitats by supporting
higher trophic guild individuals (63)
  ln estuarine discharge rateMean freshwater input, m3 s−1Sawfishes are highly associated with river and
estuarine systems (25, 64)
  ln mangrove areaMean mangrove area (km2)Sawfishes are highly associated with mangroves
(53)
  Sea surface temperatureMonthly means from 1981 to 2018 in °CSawfishes are associated with tropical waters with
a lower lethal temperature between 8° and 12°C
(64)