Demand Side Management (DSM) - an attempt by utilities to reduce customers' demand for electricity or energy by encouraging efficiency.

demersal - fish that live on or near the ocean bottom. They are often called benthic fish, groundfish, or bottom fish.

development - (1) a developed tract of land (with houses or structures); (2) the act, process or result of developing.

diesel - a petroleum-based fuel which is burned in engines ignited by compression rather than spark; commonly used for heavy duty engines including buses and trucks.

diesel engine - an internal combustion engine that uses diesel as fuel, producing harmful fumes.

dioxin - a man-made chemical by-product formed during the manufacturing of other chemicals and during incineration. Studies show that dioxin is the most potent animal carcinogen ever tested, as well as the cause of severe weight loss, liver problems, kidney problems, birth defects, and death.

double hulled tankers - large transport ships with two hulls with space between them, protecting the cargo (in most cases, oil) from spilling in case of a collision.

dredge - a fishing method that utilizes a bag dragged behind a vessel that scrapes the ocean bottom, usually to catch shellfish. Dredges are often equiped with metal spikes in order to dig up the catch.

driftnet - a huge net stretching across many miles that drifts in the water; used primarily for large-scale commercial fishing.

dump sites - waste disposal grounds.