Chapter V.--Order Ciconiiformes (Family Ardeidae 
H 
and Bitterns) ena 
Black=crowmed Night Heron 
Literature on productivity and survival 
The best quantitative nesting data on Nycticorax nycticorax 
is that reported from Massachusetts by Gross (1923). nests, the 
mean clutch was 3.2 eggs; in 199 other nests, there was a mean of 2e7 
young. The mean nwnber of young that fledge and leave the nest is not 
known. According to Bent (1926), the usual clutch is 3-5 eggs. Gross 
(1923) found birds in the first nuptial plumage active in nest building 
ae eeood abe ie eggs; they also possessed fully matured gonads at that 
Banding work in North America 
The most extensive banding work on black-crowmed night herons 
has been carried out in Massachusetts (277 recoveries of all kinds), 
with Michigan (67) next, followed by Colorado (38), New York (36), 
and Saskatchewan (33). 
From 1926 to 1941 inclusive, 70 banders ringed about 10,767 
birds of this species. By September 1, 196, these birds were repre- 
sented by about 308 usable recoveries, a recovery rate of 2.9 per 
cent. Among the unusable material were 105 reports (a) giving no 
information as to how obtained, or representing (b) birds found in 
heronries or as "remains," and (c) some that could not be verified 
against banders! schedules. 
Characteristics of the sample studied 
The migratory movements of night herons banded in Massachusetts 
have been mapped by Forbush (1925, p. xxiv) and by May (1929), who 
demonstrated a markedly random dispersal of the young birds in all 
directions. Lincoln (1936) and Cooke (1938) have listed 17 Latin 
American recoveries of U. S.-banded birds; 9 of these are reported in 
the first year of life, 2 in the second, in the third, and 2 in the 
fourth. As far as I could determine, age variations in migratory 
habits do not introduce a bias into longevity analyses for this 
species. 
In general, birds from Massachusetts west to South Dakota 
funnel toward Florida, Cuba, and the West Indies; those from California 
east to South Dakota and Nebraska move toward Mexico and Guatemala. 
The exact route taken by Illinois and Michigan birds to British Hon- 
duras is at present unknown. 
The monthly distribution of reports of black-crowned night 
herons shot or reported as found dead is given in table 22. 
First-year birds have a significantly higher number of 
reports than adults for the 4 months from August to November inclusive. 
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