130 



THE OOLOGIST. 



successively in the[same season, but I 

 do not credit this story as the owl does 

 not leave the nest with its youner until 

 after May 1, and that would not suit 

 the hawk's views, as it usually begins 

 nesting in March or early April; st 11 it 

 is possible. 



In the third division we find the En- 

 glish Sparrow in full force, aiid if liie: e 

 is one factor in the driving of our' city 

 birds from our parks and yards it is the 

 pugnacity of this despised interloper. 

 Yet in the face of all this we cannot 

 but admire the imported nuisance, for 

 the aggressiveness with which he holds 

 sway over the carefully protected birds 

 of our land. In addition to driving the 

 Martins from their boxes and the Blue- 

 birds from their cavitit-s, and tha many 

 other birds from the dooryard, we find 

 him in the country as well whtre he 

 takes possession of the n* sts of the 

 Phoebe, Eave and Barn Swallows. It 

 is intesticg to observe a pair of Spar- 

 rows, occupying a mud house in a row 

 of Eave Swallows nests The irascible 

 fellow appears contented wherever he 

 is located and always makes himself at 

 home. I do not lecali an instance 

 where one of our native small birds 

 building in the open has been dispos- 

 sessed of its homestead rights, but 

 cavities are often in dispute. Years 

 ago when the Bronzed Grackle w&s in 

 the habit of laying its eggs in the hol- 

 lows of dead trees, I have seen this big 

 shiny bird drive a pair ( f blueblack 

 swallows from their possessions in a 

 dead stub. The Short-eared Owl has a 

 penchant for building in the nest tf the 

 common crow, and after nicely lining 

 it with feathers, defends it against the 

 sable f;owners. A Sparrow Hawk has 

 been seen to drive a pair of Flickers 

 from a cavity that they had occupied 

 for years. 



Some birds will build their nests over 

 other nests; even those containing eggs 



of the same species, and again over 

 eggs of different species. The imported 

 sparrow is much given to both of these 

 oddities, but of our native birds the 

 only ones in which I have observed the 

 peculiarity are the Blue-backed Swal- 

 low and common Bluebird, in addition 

 to the second -storied nests of the Yel- 

 low Warbler, which often builds a sec- 

 ond nest over the unwelcome addi- 

 tions of the Cowbird I once found 

 three more or less complete sets cf 

 eggs of the Bluebird in a single cavity. 

 Such an occurrence can only be ac- 

 counted for in one way; the cavity was 

 first occupied by a pair of birds that 

 was driven out sfter the eggs were de^ 

 posited, or perhaps the birds were 

 frightened or destroyed. A fresh set of 

 eggs was then laid by pair number two 

 in a nest built over the first one, and 

 for a second time the cavity was de- 

 serted. Let us hope that the firt-t pair 

 rallied and again took possession of 

 the cavity. The cavity in question 

 contained three nests, occupying a 

 space from the bottom upward or over 

 eight inches. The lower set of four 

 had lain cold and deserted for a 

 month; the nest set above was at least 

 two weeks old- while the upper set was 

 in process of incubation when discov- 

 ered. The locality was a field which, 

 had recently been cleared of most of 

 its many stubs, and which had former- 

 ly been much frequented by the Blue 

 birds. On their return in the spring 

 the birds had found the accommoda- 

 tions much curtailed, p^ad in their de- 

 sire to remain and nest in the neigh- 

 borhood entered into a teighborhood 

 struggle with disasterous results. In 

 one hollow of a tamarack stub in the 

 marsh, we found a finely feathered 

 nest of the Blue-backed Swallow con- 

 taining six eggs, and beneath this an- 

 other nest held five addled eggs. 



(To be Continued.) 



Morris Gibbs,. 



