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1911 ] Kennedy, Fruit-eating Habits of the Sage Thrasher. 225 

Turkeys come, the old man Lee who kept tame turkeys told us 
of an amusing experience he had had the previous night. He had 
gone up the gulch back of his house and while there had seen an 
old gobbler, and thought he'd drive him home. But when ap- 
proached the turkey ran away from home — and when chased got 
up and flew! Surprised at this strange behaviour the old man 
went on down to the ranch. Passing his hen house he looked in 
and — there was his gobbler inside! Perhaps the turkey he had 
chased was one whose tracks we had seen on Willow Creek! 



NOTES ON THE FRUIT-EATING HABITS OF THE SAGE 
THRASHER IN THE YAKIMA VALLLEY. 

BY CLARENCE HAMILTON KENNEDY. 

The broad sage-covered stretches of the lower Yakima Valley, 
with the barren hills enclosing it, lie in the Transition and Upper 
Sonoran Zones. Only a narrow strip a few miles wide down the 
center of the valley has been reclaimed by irrigation and the brown 
desert displaced by green fields and orchards. 

It is in this sage brush land above the irrigated area that the 
Sage Thrashers (Oreoscoptes montanus), after arriving in the 
spring, nest and live until the young are capable of extended flight. 
During the nesting period they are the best singers of any of the 
sage brush inhabitants. They are also the most wary, for seldom 
can a person on foot approach one nearer than fifty yards. 

During the latter half of May, families of Sage Thrashers drift 
down into the irrigated ranches and begin their season of fruit- 
eating with the black-cap raspberries, which are then beginning 
to ripen. By this time the young, though still associating with the 
older birds, are capable of searching out their own food. With 
this independence of the young, the habits of the Sage Thrashers 
change very markedly. After this the snatches of whimsical song 
are rarely heard. From birds with a burst of song after every 



226 Kennedy, Fruit-eating Habits of the Sage Thrasher. [April 

short flight they change to the most silent of birds. During the 
entire summer's observation I have heard no call of any kind and 
on but two occasions during this period have I heard a short burst 
of song. Their shyness also leaves them. They become as ap- 
proachable as Robins in an eastern dooryard. They will sit and 
without fear eat berries within a few feet of pickers. 

Immediately following the raspberries come the blackberries. 
Both are devoured with equal readiness. Sour red berries are 
eaten as readily as the riper black ones. The berries are eaten 




i 23 

Fig. 1. A perfect bunch of Campbell's Early grapes. 

2. Campbell's Early damaged by Sage Thrashers. 

3. A damaged cluster after having been trimmed. 

whole and because of their size many of those picked off fall to 
the ground and are lost. After the blackberry season there is a 
period of two or three weeks when no small fruits are ripe. During 
this time the Thrashers stay about the ranches but content them- 
selves with an insect diet. 

At the end of this interim, the latter part of July, the early grapes 
begin to color. At first they pass unnoticed but by the time one 
half of the clusters are purple the Thrashers have commenced to 
peck them. Usually they break the skin and sip the juice but 
occasionally a grape is eaten whole. After the feeding on grapes 
commences the vineyard is never free from Thrashers, which fly 



1911 ] Kennedy, Fruit-eating Habits of the Sage Thrasher. 227 

up from the vines to near posts and silently watch any intruder. 
While during the earlier summer they flock in what are probably 
family groups, during the latter part of the summer no flocking 
occurs, though as many as a dozen individuals may be seen in the 
vineyard at one time, which on being driven out fly each in a differ- 
-ent direction. 

On this ranch there are 140 vines of Campbell's Early. The 
actual loss in weight of grapes through bird damage was 25 %, but 
the loss in profits was not less than 50 % because of the large item 
of labor in trimming damaged clusters, and the loss in fancy value 
through the unattractive appearance of the trimmed bunches (Figs. 
1-3). By September 1 the Campbell's Early were gone, and the 
Thrashers began to eat the foreign (Vitis vinifera) grapes in a 
mixed vineyard, the black varieties of which were beginning to 
color. The black varieties, Black Hamburg, Cornichou and 
Ramonia were damaged, as was also the Flame Tokay, a red 
grape. At no time did the birds injure any green or yellowish 
varieties, for among the vinifera varieties the Muscat, Malaga and 
Thompson's Seedless were untouched, while among the domestic 
varieties, the green-colored Moore's Diamond and Niagara were 
uninjured. Of red grapes the foreign Flame Tokays were damaged 
some just after coloring and while yet sour, but the red honey-like 
Delawares were untouched. The 140 vines of Campbell's Early, 
which were so badly damaged, were in the center of four acres of 
Concord grapes, which were entirely untouched. The explanation 
of this seems to be that the Thrashers prefer a grape with the two 
characteristics, a dark color and sourness. Concord grapes lose 
their acidity on first turning color, while Campbell's Early have a 
sprightly sub-acid flavor until fully ripe. Furthermore the red 
Flame Tokays were unmolested after they had ripened to sweetness. 

Ten stomachs were examined with the following results: — 





Fruit in Stomach 


Insects in Stomach 


M 


Grape pulp, skin, 2 seeds 


1 locust 


2 


Grape pulp, skin, 4 seeds 


1 large beetle, numerous ants 


3 


Grape pulp, , 4 seeds 




4 


Grape pulp, skin, 2 seeds 




5 


Grape skin 


1 locust, 3 ants, remains of other 
ants 



» Nos. 1-5 killed Aug. 20, 10 a. m. to 3 p. m. 



228 Kennedy, Fruit-eating Habits of the Sage Thrasher [apHL 





Fruit in Stomach 


Insects in Stomach 


*6 


2 Grape skins, 1 seed 


1 beetle 


7 


Grape skin, Chinese lettuce seed 




8 


Grape skin 


1 ant 


9 


Grape skin, 3 seeds 


1 beetle, 2 ants 


10 


Grape skin, 1 seed and moun- 
tain ash berry 





Thinking that the Sage Thrashers' preference for sour tastes 
might extend to their insect diet, locusts and ants were tasted. A 
locust infusion had a delicate and suprisingly pleasant flavor but 
without a trace of sourness, while the ants had a flavor almost 
identical with that of castor oil. 

The Thrashers taken on August 20 were in the midst of moult, 
while those taken on September 2 were nearly through moulting. 
A severe gale (sand storm) occurred on September 14. On Sep- 
tember 15 small flocks of Thrashers were seen in roadside weed 
patches (an unusual place to find Thrashers), after which none were 
seen except one lone Thrasher seen in the vineyard two diff . rent 
days in November. 

The Thrashers were assisted to some extent in their depreda- 
tions on the early grapes by Bullock's Orioles. After the Thrashers 
had left for the south, Robins, while flocking preparatory to migrat- 
ing, injured the very late grapes. 
Sunnyside, Wash. 

'Nos. 6-10 killed Sept. 2, 6:30 a. m.