DUCKS, GEESE, AND SWANS. 233 
seen in any numbers on our seas before October ; 
but from that date onwards vast flocks continue to 
arrive, and the bird continues abundant until the 
end of the following March. Certainly some 
districts are far more favoured by this species than 
others. In my own experience I may name the 
Wash, where I have seen this Goose in such 
enormous packs as densely to cover many acres of 
mud-flat; whilst their noisy clamour, in the still 
hours of early morning, could be heard for a mile 
or more across the wide, desolate salt-marshes. 
The Brent Goose passes its time either on the sea 
or on the muds. It is remarkably gregarious, young 
and old congregating together, wary and watchful 
always, and never allowing a close approach on the 
land. So densely do the birds pack, that a disturbed 
flock taking wing looks as though the very surface 
of the mud or sea were rising in one solid, in- 
separable mass. The principal food of this Goose 
consists of grass, wrack, and laver. On certain 
mud-banks these plants grow very thickly, and to 
these the Brents resort as soon as the tide recedes 
sufficiently for them to reach and to tear up their 
favourite food. In studied order the birds advance, 
feeding as they come, sentinels remaining on the 
look-out in turn, until all are satisfied, or the in- 
coming tide covers their food-plants. Then back, 
in a solid mass, they go towards the open sea, or to 
some low bank, there to rest and preen their plumage, 
and to wait until another tide has ebbed, and left 
