Observations were made on Grey and Red-Necked Phalaropes near Chesterfield Inlet, N.W.T., Canada, from the date of their local arrival, 13 June, until 21 July 1967.
The similarity of the colour of the Grey Phalarope nuptial plumage to that of dead seaweed among which the birds often feed is suggested as possibly relevant to the evolution of this plumage.
A mutual Head Up pre-copulatory display, first given by the female, is described in Grey Phalaropes. It is suggested to have the function of assuaging fear in the prospective partner and to be a prelude of only the first copulation between any two birds. Other displays are described and figured.
Three full copulations, including their preliminaries, were observed in this species and two others in which the preliminary actions escaped observation. Three copulations took place on land and two on water. Of the three copulations observed with their preliminaries, two were initiated by some form of display by the female, and one, without any display, by the male. Eight attempted copulations were observed; all were initiated by males and all but one took place while the female was on land. One male which had just copulated was observed to attempt copulation with another female. In the course of three full or attempted copulations, another Grey Phalarope fluttered up against the mating pair.
All Grey Phalarope copulations took place in a collective feeding area; little intra-species antagonism was seen and no evidence of territorial behaviour. All female Grey Phalaropes left the colony under observation on the night of 9–10 July; only two eggs had by then been laid in one nest and the female of one pair had not laid at all.
Six copulations and six attempted copulations were observed in Red-necked Phalaropes; all took place on the water. Only in two of the copulations were the preliminaries observed; one was initiated by a display of the female, the other without any preliminary display by the male.
Preliminary observations suggest specific differences in rate of spinning and in the preferred direction of spin. The functions and factors associated with spinning are discussed. Accelerated spinning with reduced frequency of pecks at the water by both members of a pair of Red-necked Phalaropes was observed once and may have been a form of display.
Head scratching, observed once in a Red-necked Phalarope and several times in Wilson's, is by the direct method, supporting the view, based on the colour pattern of the downy young, that phalaropes are more akin to the sandpipers than to the avocets.