My comical pet blue jay gave proof of the need of parental training. While he intuitively called like a jay, he never was able to sing the sweet, gurgling roulade of the wild jays. On the contrary, he treated us to all kinds of odd, imitative, mirth-provoking performances that no self-respecting jay in the open would think of enacting. After several months of cage life he was given his liberty. Now, indeed, he showed his lack of jay bringing up, and how little, in some respects, mere instinct can be relied on. When evening came he perched on a limb of the maple tree before the house, in a place as exposed as he could well find, not knowing that there was more danger in an outdoor roost than in his shielding cage. I could not induce him to come down, nor could I climb out to the branch on which he sat, and so I was compelled to leave him out of doors.
The next morning he was safe, the screech owls of the neighborhood having overlooked him in some way. The next evening he went to roost in the same exposed place, and that was the last I ever saw of my beloved pet. He was undoubtedly killed and devoured by the owls. Had he been reared out of doors in the usual way, his parents would have taught him to find a roosting place that was secure from predatory foes. No one has ever seen a wild jay sleeping in an exposed place.
In her charming little book, "True Bird Stories," Mrs. Olive Thorne Miller says that she "once watched the doings in a crow nursery." I quote:
"The most important thing the elders had to do was to teach the youngsters how to fly, and every little while one or both of the parents would fly around the pasture, giving a peculiar call as they went. This call appeared to be an order to the little folks to follow, for all would start up and circle round for a minute or two, and then drop back to the fence or the ground to rest.
"Once, while I was watching them, this cry was given, and all flew as usual except one bob-tailed baby, who stood on a big stone in the middle of the field. He was perhaps so comfortable that he did not want to go, or it may be he was afraid, and thought mamma would not notice him. But mothers' eyes are sharp, and she did see him. She knew, too, that baby crows must learn to fly; so when all came down again she flew right at the naughty bird, and knocked him off his perch. He squawked, and fluttered his wings to keep from falling, but the blow came so suddenly that he had not time to save himself, and he fell flat on the ground. In a minute he clambered back upon his stone, and I watched him closely. The next time the call came to fly he did not linger, but went with the rest, and so long as I could watch him he never disobeyed again."
This is evidence not only of parental teaching, but also of parental discipline. Here is another bit from the same volume, bearing its lesson on its face. "A lady told me a funny story about a robin. He was brought up in the house from the nest, and never learned to sing the robin song, for he had not heard it. He plainly tried to make some sort of music, and one of the family taught him to whistle 'Yankee Doodle'. He whistled it perfectly, and never tried to sing anything else. Once this Yankee Doodle robin got out of the house and flew up into a tree. When the wild birds came about him he entertained them by whistling his favorite air, which sent the birds off in a panic."
Do not the facts recited in this sketch prove that birds know and acquire some things through the promptings of instinct, while other things they can learn only by avian teaching?
My notes on instinct and education in bird song correspond with the conviction expressed by Dr. W. H. Hudson on page 257 of his interesting book entitled "The Naturalist in La Plata," fourth edition, 1903: "It is true that Daines Barrington's notion that young song birds learn to sing only by imitating the adults, still holds its ground; and Darwin gives it his approval in his 'Descent of Man'. It is perhaps one of those doctrines which are partly true, or which do not contain the whole truth; and it is possible to believe that, while many singing birds do so learn their songs, or acquire a greater proficiency in them from hearing the adults, in other species the song comes instinctively, and is, like other instincts and habits, purely an 'inherited memory'." What Dr. Hudson surmises may be the case, I believe my experiments have proved to be true.