Many diadromous species support important commercial and/or recreational fisheries. The commercial harvest of these species provides jobs, economic development, and puts fish on the grocery store shelves. Recreational fishing also provides jobs and economic development.
In addition, these species have an important role within the ecosystem. Diadromous fish eat small fish, insects, and plants, and are a food source themselves for larger fish, birds, and mammals. This part of a food web is an important link in energy transfer between primary producers (plants), and top-end consumers (humans and other animals that are not generally preyed upon by other animals). When a portion of the food web is disrupted, it can affect the entire food web--not just that portion.
