Final answer:
The Channel Islands harbor would likely need to be dredged the least.
Step-by-step explanation:
The question is asking which of the four harbors needs to be dredged the least. Dredging is the process of removing sediment or other material from the bottom of bodies of water to increase the depth and maintain navigability of the harbor. In this case, the harbor that would need to be dredged the least is the one that experiences the least sediment accumulation.
It is important to note that sediment accumulation can be affected by various factors, such as currents, tides, and human activities. Therefore, further study and assessment would be necessary to determine the specific dredging needs of each harbor.