The season is detected by the aspect of the clouds.

March 22.

P. M. – Launch my boat and row downstream.

There is a strong and cool northwest wind. 

Leaving our boat just below N. Barrett's, we walk down the shore. We see many gulls on the very opposite side of the meadow, near the woods. They look bright-white, like snow on the dark-blue water. It is surprising how far they can be seen, how much light they reflect, and how conspicuous they are. Being strung along one every rod, they made me think of a fleet in line of battle. 

We go along to the pitch pine hill off Abner Buttrick's, and, finding a sheltered and sunny place, we watch the ducks from it with our glass. There are not only gulls, but about forty black ducks and as many sheldrakes, and, I think, two wood ducks. The gulls appear considerably the largest and make the most show, they are so uniformly light-colored. 

At a distance, as I have said, they look like snowy masses, and even nearer they have a lumpish look, like a mass of cotton, the head being light as well as the breast. They are seen sailing about in the shallow water, or standing motionless on a clod that just rises above the surface, in which position they have a particularly clumsy look; or one or two may be seen slowly wheeling about above the rest. From time to time the whole flock of gulls suddenly rises and begins circling about, and at last they settle down in some new place and order. 

With these were at first associated about forty black ducks, pretty close together, sometimes apparently in close single lines, some looking lumpish like decoys of wood, others standing on the bottom and reminding me of penguins. They were constantly diving with great energy, making the water fly apparently two feet upward in a thick shower. Then away they all go, circling about for ten minutes at least before they can decide where to alight. 

The black heads and white breasts, which may be golden-eyes, for they are evidently paired, male and female, for the most part, —and yet I thought that I saw the red bill of the sheldrake [They are sheldrakes], —these are most incessantly and skillfully plunging and from time to time apparently pursuing each other. They are much more active, whether diving or swimming about, than you expect ducks to be. Now, perchance, they are seen changing their ground, swimming off, perhaps, two by two, in pairs, very steadily and swiftly, without diving. 

I see two of these very far off on a bright-blue bay where the waves are running high. They are two intensely white specks, which yet you might mistake for the foaming crest of waves. Now one disappears, but soon is seen again, and then its companion is lost in like manner, having dived. 

I see those peculiar spring (?) clouds, scattered cumuli with dark level bases. No doubt the season is to be detected by the aspect of the clouds no less than by that of the earth.

H. D. Thoreau, Journal, March 22, 1858

Launch my boat and row downstream. See March 16, 1859 ("Launch my boat and sail to Ball's Hill. It is fine clear weather and a strong northwest wind"); March 17, 1857 ("Launch my boat."); March 19, 1855 ("Launch my boat.");March 22, 1854 ("Launch boat and paddle to Fair Haven. Still very cold"); April 19, 1858 ("Spend the day hunting for my boat, which was stolen.")

Forty black ducks, pretty close together, sometimes apparently in close single lines. See March 22, 1854 ("Scare up my flock of black ducks and count forty together.")

Sheldrakes two by two. See March 5, 1857 ("I scare up six male sheldrakes, with their black heads, in the Assabet,—the first ducks I have seen"); March 16, 1855 ("Scare up two large ducks . . . I think it the goosander or sheldrake."); March 16, 1854 ("I see ducks afar, sailing on the meadow, leaving a long furrow in the water behind them."); March 16, 1860 ("Saw a flock of sheldrakes a hundred rods off, on the Great Meadows, mostly males with a few females, all intent on fishing.”) See also A Book of the Seasons, by Henry Thoreau, The Sheldrake (Merganser, Goosander)

They look bright-white, like snow on the dark-blue water. It is surprising how far they can be seen, how much light they reflect, and how conspicuous they are. See April 15, 1855 ("It is remarkable how much light those white gulls . . . absorb and reflect through that sombre atmosphere, — conspicuous almost as candles in the night."); March 29, 1854 ("A gull of pure white, - a wave of foam in the air.")