The majority of pelagic and semidemersal fish range freely throughout the 

 water column. Planktonic and nektonic feeders feed primarily in the water 

 column. Fishes are discussed in detail in chapter 11, "Fishes." 



The primary waterbirds feeding in inshore open water are common terns, 

 cormorants, eiders, guillemots, bay ducks, and sea ducks. Birds feeding in 

 offshore water include kittiwakes (mostly winter), artic terns (summer), large 

 alcids (throughout the year), phalaropes (migration), shearwaters (summer), 

 fulmar (fall, winter, and spring), and petrels (summer). Common terns, large 

 alcids, and shearwaters eat mostly fishes. Arctic terns, fulmars, and 

 Bonaparte's gulls eat fishes, copepods , and euphausiid shrimps. Petrels and 

 phalaropes feed mostly on copepods and the smaller-sized classes of 

 euphasiids . 



Large concentrations of seabirds occur in open water, especially near 

 upwellings, tidal rips, and slicks. In August, concentrations of northern 

 phalaropes number over 1 million in open water off Eastport (region 6), south 

 of Grand Manan (region 6), and near Mt . Desert Rock (region 5). Phalaropes 

 numbering in the hundreds of thousands have been reported near Machias Seal 

 Island in spring. Large mixed flocks of Bonaparte's gulls, large gulls, 

 shearwaters, fulmar, kittiwakes, and terns may occur over local food 

 concentrations. The large seabird concentrations near Eastport feed on the 

 euphausiid surface swarms and on herring and other finfish (see chapter 14, 

 "Waterbirds"). 



Many waterfowl that feed on intertidal flats rest in 'rafts' (large groups) on 

 open water, especially when the flats are inundated. Many of these rafts are 

 located on the lee side of islands and ledges (see chapter 15, "Waterfowl"). 



Marine mammals are discussed in chapter 13, "Marine Mammals," and in this 

 chapter. 



Class: unconsolidated bottom . Unconsolidated bottoms are characteristic 

 of the majority of the subtidal marine environment. In NWI terms, beach/bar, 

 open water (i.e., unknown bottom), unconsolidated bottom, and flat habitats 

 are all classed as unconsolidated bottoms. 



Unconsolidated bottoms are sedimentary deposits of glacial or recent origin of 

 which many types exist: gravelly sand, silty sand, and sand and mud. The 

 gravelly sand and silty sand deposits are offshore from present-day beach and 

 fluvial systems. The gravelly sands offshore are marginal to the larger 

 island complexes in Knox and Hancock Counties (regions 4 and 5) and are 

 probably relict glaciof luvial gravels. Marine mud sediments fall into two 

 types (Schlee 1973). Veneering the offshore areas of the midcoast areas are 

 pelagic deposits of sandy mud. Areas offshore from Hancock and Washington 

 Counties (regions 5 and 6) have a smaller sand fraction and approach true 

 silt-clay mixture muds. 



Sediment composition of unconsolidated bottom deposits is dependent upon 

 sediment sources. Gravel fraction compositions probably reflect onshore 

 bedrock compositions, sand and silt fractions are most commonly dominated by 

 quartz and feldspar minerals, while the clay fraction is composed mostly of 

 illite, chlorite, and hornblende, reflecting the metamorphic bedrock terrain 



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