February, 1922.] 



The Canadian Field-Naturalist 



27 



are poplar and alder stands, several acres in ex- 

 tent. The fore-shore is boggy and alkaline for 

 the most part, with infrequent stretches of narrow 

 sandy beach. Where the lake bottom is sandy, 

 bog rush is the chief aquatic growth, but in the 

 muddy portions there is a heavy growth of tules, 

 several hundred yards wide in some places. The 

 marsh area is widest at the north end of the lake 

 and is intersected by several weed-choked lagoons. 

 The lake is shallow, probably not exceeding eight 

 feet in depth, and is fed by two small streams, 

 one at each end. The only outlet is a small 

 stream at the north end, which joins Long Lake 

 Creek near Vernon. 



Trout are said to have been plentiful at one 

 time, but none have been caught within recent 

 years. Thee is, howevar, an abundance of 

 Cyprinoids and several species of larger coarse 

 fish, which supply the needs of Loons, Ospreys, 

 Kingfishers and other fish-eating birds. 



This shallow lake with its encircling marsh is 

 probably more prolific in bird life than any other 

 lake of its size in the Okanagan Valley. The 

 growth of marsh plants, thriving in the warm 

 water and drawing vitality from the decay of 

 past years, is amazingly rapid, and fortunately 

 the carp, which are reducing the marshes in the 

 lakes of the Okanagan chain, have not yet made 

 their appearance. 



On a day in June, this expanse of waving green 

 and the air above it fairly hum with insect life. 

 The water, too, is alive with little fish, with 

 crustaceae and with the larvae of the insects that 

 swarm on the plants above. To this endless 

 banquet come the birds in their hundreds. Marsh 

 Wrens peer from the tule clumps and burst into 

 ecstacies of song; Black Terns skim past, barely 

 clearing the tule tops; Coots, Red-heads and 

 Ruddy Ducks swim by in friendly unconcern, 

 while a never-ending procession of Swallows and 

 Red-winged and Yellow-headed Blackbirds fly 

 back and forth. This is accompanied by an 

 almost deafening volume of bird voices, the 

 clamor of Black Terns, chuckling of Coots, rasp- 

 ing of Yellow-heads, the yelping of Hoiboell's 

 Grebes, the pumping of Bitterns and, cutting 

 through this medley like a knife thrust, the wild, 

 Valkyrie call of the Loon. 



The fringe of brush along the shore is also 

 alive with birds Eastern and Western King- 

 birds, Western Wood Peewees, Alder Flycatchers, 

 Crows, Bullock's Orioles, Sooty Song Sparrows, 

 Red-eyed Vireos, Yellow-throats, Yellow Warblers 

 and a dozen other species no stretch of woodland 

 of whatever fertility could support this wealth of 

 bird-life. The North Arm of Okanagan Lake, 

 only a short distance away, is of the same general 



character shallow water and marsh-bordered 

 shores yet it supports a much smaller and less 

 diversified population. 



The boggy tule-lined shores and the weedy 

 stretch of water are often viewed with hostility, 

 and at one time a scheme for draining the lake 

 was contemplated. Fortunately this vandalism 

 was abandoned and it is to be hoped that such 

 an exceptionally attractive breeding-ground for 

 water-fowl will be left in their undisturbed 

 possession for all time to come. 



The following notes were made during the 

 summers of 1916 and 1918 when I spent several 

 days exploring the marsh and studying the birds 

 breeding in it. 



Holboell's Grebe: Colymbus holboelli. On 

 May 15th, 1916, flocks of Holboell's Grebe were 

 seen in the open watsr chafing one another with 

 a great deal of splashing, and calling in chorus. 

 Their courtship is a rough and tumble affair, 

 consisting chiafly on tha part of the males in a 

 display of pugnacity towards others of their sex, 

 and, on the part of the females, of a waiting 

 attitude. There is none of the graceful posturing 

 and display-flights that make the courtship of the 

 more highly organized diving-ducks such a delight- 

 ful spectacle. 



A partial exploration of the marsh three weeks 

 later brought to light twenty nests, some only 

 recently completed and empty, others containing 

 from one to four eggs. The nests varied slightly 

 in size, but otherwise were identical sodden 

 masses of bog rush, black with a season's decay, 

 floating with the larger portion below the surface. 

 Generally, they were moored in a clump of rushes 

 and, in most cases, close to the outer edge of the 

 marsh where the water was from two to four feet 

 deep. My noisy approach through the rustling 

 tules was sufficient to alarm the sitting bird and 

 she or he (as both sexes help in the work of in- 

 cubation) would slip off the nest and glide through 

 the tules to the open water without being seen. 

 Usually the mate was not far off and, together, 

 they would swim back and forth in front of the 

 nest, some thirty or forty yards from the marsh. 

 Frequently, the sitting bird had had suflRcient 

 warning to cover the eggs with some of the loose 

 material on the nest, and in only a few cases were 

 they found exposed. 



Usually, they were embedded in the rotting 

 material composing the nest and, no doubt, the 

 heat from this source assisted materially in their 

 incubation. 



One bird, apparently a female, was seen with 

 a single youngster riding on her back. Perhaps 

 the rest of the brood had been killed by muskrats 

 as several partly eaten bodies of downy young 



