Question: Which species on Réunion island is part of the procellariiformes order and is part of the hydrobatidae family and has less than 21 species worldwide?
SQL: SELECT SUM("Species on Réunion") FROM "2-12533665-1" WHERE "Order" = 'procellariiformes' AND "Family" = 'hydrobatidae' AND "Species worldwide" < 21.0;

Question: How many species does the sternidae family have worldwide with less than 9 species on Réunion?
SQL: SELECT COUNT("Species worldwide") FROM "2-12533665-1" WHERE "Family" = 'sternidae' AND "Species on Réunion" < 9.0;

Question: How many species on Réunion do the dromadidae family have with a worldwide speices larger than 1?
SQL: SELECT SUM("Species on Réunion") FROM "2-12533665-1" WHERE "Family" = 'dromadidae' AND "Species worldwide" > 1.0;