There are certain supplementary sources of revenue which might help to offset some of the costs.
Algae provide giant clams with a supplementary source of nutrition.
The fruit may be used as a supplementary source of food by rural people during times of shortage.
Dairy is the main supplementary source of income of the farmers in the district.
From 1950 to 1984 live stock enterprise developed very fast and it was a single or supplementary source of income for nearly 30% of the district population.
Eaten for about a month, the pap provides a supplementary source of protein at a transition time from a milk to a leaf diet.
This puts the wind as a potential supplementary source of energy generated by hydroelectric.
Migrating birds rely largely on stored fat and they also metabolise protein as a supplementary source of energy.
Its population exceeds 4,000 most of who depend on tobacco farming as their main or supplementary source of income.
As they came to rely upon cereal foods over salty meat and fish, Neolithic cultures had to incorporate supplementary sources of salt into their diet.