110 
THE CONDOR 
Vol. XVII 
The Olive-backed Thrush (. Hylocichla ustulata swainsoni ) is by far the 
most abundant bird about the station. Up till late July these birds sang very 
frequently. Often eight different birds were heard in song at the same time. 
The songs were heard throughout the greater part of the day, only ceasiiig for 
a few hours at noon. This song, while pleasing at first, is of much poorer 
quality than the less frequent songs of other thrushes, so that in time it loses 
its charm and becomes decidedly monotonous. The nests of this thrush are 
easily found. They outnumbered all others to such an extent that 1 found an 
average of nearly three of them to one nest of any other bird. 
I had not been at the station long before the first addition to the list of 
Flathead birds was made. This was a male Rocky Mountain Pine Grosbeak 
( Pinicola enucleator montana ) that, was discovered on the morning of June 27 
by Dr. M. J. Elrod, Director of the Station, in the fir trees not far back of the 
Station building. We watched the bird for some time and easily identified it 
before it flew off. It is quite probable that this bird is a common summer resi- 
dent of the higher mountains nearby, but what it was doing here in the Transi- 
tion zone, and in the breeding season, is a puzzle. It was not seen again and 
probably returned to the higher mountains where it belonged. 
Fig. 40 . Osprey Island, Flathead Lake, Montana 
On the same day that this bird was found, a trip was made to one of the 
numerous small islands near the southern end of the lake. A pair of Ospreys 
( Pandion haliaetus carolinensis ) was occupying a large and conspicuous uest 
placed in a dead fir at one end of the island. Their presence here for a number 
of seasons had given this the name of Osprey Island. It is evident that the 
Osprey is one of the birds that is decreasing in numbers in this locality. Nests 
that had been occupied in former years were common about the lake shore; but 
this was the only occupied nest that 1 saw during the entire season. (See fig. 
40.) 
The top of Osprey Island is covered with a dense thicket of bushes, and 
about its edges are numerous dead fir stubs and a few live cottonwoods. The 
whole island is small, only a few acres in extent, but the bird life on it is abund- 
ant. Nests were numerous, and altogether I found on it, in the course of half 
an hour, more nests than I found in all other places about the lake put together 
during the entire summer. Yellow Warblers ( Dendroica aestiva aestiva) were 
perhaps the most numerous, but Olive-backed Thrushes, Robins ( Planesticus 
migratorius prminquus), and Catbirds ( Dumetella carolinensis) were not far 
