.--After a
successful study with captured adult blue jays during the lte summer of 1965
(Mitrefling, L. A. 1966. Construction of a "beta-confinement" bird enclosure.
Bird-Banding 37: 123-125) an attempt was made to raise young jays for more
detailed studies in 1966. I)espite later catastrophes, the fledgling study was
measureably successtiff and l hree (,f them are shown in Fig. 1.
The jays from nest (me (identified as jays 1 through 5 in Table l) were taken
(}n the night of June 19. These were smaller and younger than desired; ()lily down
was present in the caudal pteryla (tail region) although sheaths (rectrice shafts)
with white apical barbs of some immature vaned feathers were developing, typical
of 13 day old birds described by Arnold (1938. The systematic position and natural
history of the northern blue jay Cyanocitta cristata bvmia ()be:boise:. Phl) Thesis.
Cornell University). However, ince the nesl was disturbed and the adult
agitated the removal was made as plmmed.
The jays from nest two (identified as 6 through 8 in Table 1) were taken on
the evening of June 21. The ages of these were also unknown but they were older
than those from nest one. ()he of them had to be captured after it flew to the
grotrod, typical of 17 to 20 day old jays described t)y Armfid.
Fmt-lU 1. Three jays removed from the nest during the third week of June
and raised to the body weight of adults .hdy 1. Ph.tographed July 3, 1966.
The jays from nest one ate readily from the first day. The jays from nest
two did not eat readily and during the early feedings had to be f.rcibly fed. The
feeding lessons they learned from the jays of nest one perhaps helped, but later
their aggression had to be quelled when feeding the smaller jays.
When the birds were determined to have approached the weight of an aduB
bird it was decided to train them to self feeding with an adult, other methods hav-
ing failed. Since they were being hand fed only twice a day, those from nest one
were anxious to eal. Three of them died of :'crazy food" poisoning when they
were inadvertently fed some old wet ma.h. July 5 all five remaining young jays
came t.o the feeding station for fi,od. Xone of them would readily m'cept hand
feeding on July 8, but thev were not agitated by the active presence of people
around the cage. The aduft was in a contimmus slate of discomposure when any
a. ctivity was conducted within 12(t' of the cage.
July 16, all jays appeared to be living comfortably but the feeding stations
were made water tight to prevent an occurrence as happened with the wet mash
earlier. The young jays permitted themselves to be handled, although with some
reluctance, but jay 6 was particularly sassy and aggressive. At 9:30 A.M. on July
22 the yonng jays were found dead in the cage. Jay 7 was headless on the ground
but only wings and other portions of jays 1, 5 and 8 were present. Jay 6 was found
(m the ground with a large ()pen wound on the right femur. The adult was ex-
tremely agitated but apparently unharmed.
TABLE 1. CAPTIVE NESTLING BLUE JAY WEIGHTS DURING THEIR
FLEDGLING PERIOD IN ,JUNE 1966.
Blue jay
Identity
Dates weighted
June 20 June 23 June 27 July 1
Gins. G ras. Gins. Gms.
1 68.0 65.0 80.0 83.5
2 65.0 60.0 76.0 81.0
3 66.0 64.0 77.0 82.0
4 69.0 63.5 78.0 83.5
5 68.0 65.5 83.0 87.5
6 -- - 68.0 78.0 77.0
7 75.0 79.0 80.0
8 76.0 81.0 84.0
An adult captive jay, held in captivity 8 days, was 85.0 Gms. on July 1,
1966. The range of weights for adult jays captured in 1965 was 76.0 to 93.0 Gms.
The record on Jay 6, from nest two, is worth considering from the standpoint
of imprinting. It was the last bird to feed without force feeding after capture; it
was the first to feed from a self feeder (3 to 4 days sooner than the others); it was
the first to fail to come to the hand feeding station and although it was "tame" it
was wary. On June 29 it was treated for a wound on the upper mandible at the
base of the beak. It was caused by pecking the wire mesh of a carrying cage,
typical of captive adult activity. The injury was probably the major reason for its
loss in weight on July 1.
Although the study was undesireably and prematurely concluded much was
learned relative to the handling and feeding of the jays. The basic diet was a
chicken starter mash containing antibiotics (supplied by the University Poultry
Department). It was made into a wet mash mixture by milk or water to which
hamburger or canned dog food was added. The mash with water and dog food
appeared to have been the most acceptable. Lloyd A. Mitterling, Assistant Pro-
fessor of Pomology, University of Connecticut, Storrs, Connecticut.