The Schuylkill Heronries 



By F. L. BURNS, Berwyn, Pa 



IT IS well known that the Black-crowned Night Heron returns year after 

 year to the same breeding-place, and that the heronries are permanent if 

 undisturbed. I believe that the colonies of the Schuylkill River region 

 are of comparatively recent occurrence, since they were unknown to our earlier 

 ornithologists, and Wilson and Audubon were very familiar with this ground. 

 It would seem probable that the breaking up of the great tide-water colonies 

 of the lower Delaware valley compelled this species to seek asylum inland; 

 and the selection of isolated groves situated on rising ground, often at a con- 

 siderable distance from any large stream or swamp, proves that even this 

 apparently stupid bird has profited by experience. However, nesting early in 

 April before the leaves have formed, it is at a distinct disadvantage in a decid- 

 uous wood. 



Heronries containing over one hundred pairs of birds are unusual in this 

 region for economic reasons. There is, of course, a limit to the feeding-range, 

 probably of 15 miles radius in the breeding-season, and even then there must 

 have been an overlapping in the hunting-grounds of the various colonies, since 

 the extreme distance between the Fort Washington and Weisenburg colonies 

 is only 40 miles. I am sure that some sort of communal leadership exists in 

 every colony and an interrelationship of all the colonies of this region. 



The first colony of which I have knowledge was located in a grove at the rear 

 of the old encampment of Wayne's brigade, Valley Forge, Chester County. 

 About 1870 a party of Norristown gunners slaughtered many of the breeding 

 birds, and the site was abandoned; the survivors are said to have formed, or 

 materially increased, a colony situated on the Skippack, just above its juncture 

 with the Perkiomen Creek, near Evansburg, Montgomery County. Dr. W. E. 

 Hughes visited it some time previous to 1880, Messrs. F. S. Rose and J. H. 

 Wilson in 1885, and it was found in about the same place as late as 1892, though 

 greatly reduced. Continued persecution had driven it further up the Perkio- 

 men when Mr. R. C. Harlow found about twenty nests on the lower slope of 

 Spring Mount near Zieglersville, in 1907, and it was deserted two years later. 



Dr. Warren states, in 1888, that a colony existed for many years along a 

 good-sized stream near Blue Rock, Berks County. 



About 1886 Mr. D. N. McCadden and Dr. Hughes discovered two large colo- 

 nies, scarcely a mile apart, in detached groves at Port Kennedy and Red Hill. 

 I visited the former in 1900 and found about fifty nests in the tallest oak and 

 chestnut trees. Every heronry seems compelled to support one or more families 

 of thievish Crows, but this community for many years had a sort of feudal 

 lord in the form of a Cooper's Hawk. No Heron would build near his nest, 

 hence part of the nests were on the top and the remainder at the foot of the 

 hill. I visited the locaHty on April 16, 1905, and counted fifty-seven nests, all 



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