PURPLE MARTIN 
BREEDING RECORDS 
TS OR YOUNG 
950 — 
900 — 1949 
SEFORE 1900 
gS OR SINGING 
LES (JUNE) 
950 — 
900 — 1949 
EFORE 1900 
) 
DOUGLAS 
Ril l 
Fig. 30.—Breeding records for the purple martin in Illinois. 
or productivity for any Illinois population of pur- 
martins. At St. Louis in 1888, Widmann aig22) 
rded hatching success of about 58 percent and 
zing success of 50 percent (of all eggs laid) in a 
ple of 45 nests with 220 eggs. Widmann believed 
success was very low for eggs produced in early 
| because of the martins’ tendency toward inat- 
iveness early in the season, allowing for interfer- 
from house sparrows, house wrens (Troglodytes 
m), and other nest usurpers. ‘Though there are 
erous references to the martins’ problems with 
‘ows, quantitative data on the effects of sparrows, 
1s, starlings, or other cavity nesters on martin pop- 
ons are lacking. Brinkman (1967) described an 
resting case in which a large colony (21 nest 
s) of martins flourished in Hoyleton, Illinois for 
suntil the (human) owners of the colony moved 
y- In succeeding years the boxes were completely 
n over by starlings. Other species mentioned as 
competitors or predators are the red-headed 
dpecker, crested flycatcher (Myitarchus crinitts), 
Jay (Cyanocitta cristata), and bluebird (Ridg- 
1915, Reiss 1971, Meany 1945, and Silloway 
). In urban areas none of the latter species 
d be considered a significant problem to the 
martin now, as none of them competes as well as 
the martin does with sparrows or starlings. 
The phenomenon of young martins leaving their 
nests prematurely is not uncommon, and has been 
variously ascribed to excessive heat stress, high ecto- 
parasite infestations, and starvation during periods of 
cool weather (Weber 1954, Widmann 1922, Gault 
1934-1935, and Bartel 1946). Widmann and Gault 
both believed that grounded young martins were usu- 
ally soon abandoned by the adults; thus it is impor- 
tant for the young to be competent flyers at the time 
of fledging, and the nestling period is consequently 
long. Because of the heat problem Gault (1934-1935) 
and others have emphasized the need for well-venti- 
lated nest boxes, and even the use of double roofs for 
insulation (Widmann 1905). Persons wishing to at- 
tract purple martins with nest boxes should read Wid- 
mann (1905), Gault (1934-1935), Bartel (LG 4iy 
Wade (1968) and Anon. (1968) for valuable infor- 
mation on box design and placement. 
References to the production of two or more 
broods of martins in one year (Eaton 1878, Johnston 
& Hardy 1962, and Hamilton 1969) have apparently 
not been based on observation of banded birds. Wid- 
mann (1922) was very doubtful of double-brooded- 
ness in this species, and Johnston & Hardy (1962) be- 
lieved that it was very unusual. 
Widmann’s (1884) day-long observations on the 
feeding of nestlings are the only quantitative data on 
this phase of the nesting cycle. He watched 16 nests 
and found that both parents fed the young, though 
the female (1,823 feeding trips at all nests) was more 
active than the male (1,454 feeding trips at all nests) . 
At different nests, each pair made from 20 to 312 trips 
during the day (4:30 a.m.—8:00 p.m.) , depending upon 
the number and size of the young (312 trips to a nest 
with four young about 2 weeks old). The youngest 
birds were fed mainly crushed small beetles, and older 
nestlings got dragonflies, grasshoppers, and butterflies. 
In northern Illinois Gault (1934-1935) also observed 
that butterflies, notably monarchs (Danaus plexippus), 
and dragonflies, notably the large Anax junius were 
favored as food for young martins. There is no other 
information on the food of either young or adult 
martins in Illinois. The often repeated claim that 
martins eat 2,000 mosquitoes per day is not founded 
on reliable evidence. Because martins feed on the 
wing, quantitative determinations of food consump- 
tion are extremely difficult to make, but even qual- 
itative determinations based on stomach examinations 
or field observations are very much needed. 
Roosting 
By the first of August in Illinois most of the young 
martins have fledged. Some reach this stage during 
June in the south (Johnston & Hardy 1962), and late 
June in the north (Schafer 1922). After fledging, the 
young, and some adults, often return to roost each 
33 
