For two years researchers used a variety of methods, including radar, acoustic devices and visual surveys, to build a map of the area's least and most sensitive areas.
The DEP said areas proposed for wind farms all lie in minimally sensitive areas.
Dan Wilkinson of Geo-Marine said that the most sensitive areas are not necessarily off-limits to development, but may require greater mitigation and monitoring costs.
The study found that a small percent of birds seen were flying in an area that could be occupied by turbines. The researchers said that mitigation techniques, including turbine shut-downs during peak bird migration seasons, could limit turbines' impact.
They also said developers could use noise reduction techniques to ease the impact of construction on dolphins.
The final report is due to be published in July.
Last year the federal government approved four leases for developers to carry out meteorological studies off the New Jersey coast.
One lease each was awarded to Bluewater Wind (which also won a lease for a spot off the coast of Delaware) and Fishermen's Energy. Deepwater Wind won two leases.