Duration of Dependence of Wild Fledgling Mourning Doves upon Parental Care

Abstract

The duration of dependence of wild fledgling mourning doves (Zenaida macroura) upon parental care was determined in east-central Alabama from March through September 1980-81. Data on behavioral interactions with parent doves were collected from 35 nestlings-fledglings equipped with radio transmitters and 34 nestmates marked with colored wing tags. Fledglings were fed consistently by at least one parent through 27 days posthatching (PH), but began feeding themselves at 17 days PH. After 16 days PH, feeding of fledglings was primarily the responsibility of the male parent. Fledglings attained feeding independence by 18 or 21 days of age if adequate food was present within 50 or 200 m, respectively, of the nest tree. Brooding and roosting interactions with parent doves were infrequent and appeared to be unimportant to survival after fledging (approximately 15 days PH). Certain parent-fledgling behavioral interactions (feeding and brooding) were protracted during late-season nestings, but the duration of absolute fledgling dependence upon parental care was not affected. J. WILDL. MANAGE. 48(1):99-108 Mourning doves are a multibrooded species requiring 30-35 days to complete a nesting cycle (Austin 1951, Cowan 1952, Mackey 1954, Swank 1955). Three-7 days are required for courtship and nest building (Cowan 1952, Mackey 1954), 14-15 days for incubation (Moore and Pearson 1941, Webb 1950, Austin 1951, Hanson and Kossack 1963), and 11-15 days for brooding (Nice 1922, Austin 1951, Cowan 1952, Mackey 1954, Swank 1955). Both parents incubate the eggs and feed and brood the young until they fledge (Taylor 1941, Harris et al. 1963). The length of time wild mourning doves are dependent upon parental care has not been precisely determined. Such information is necessary to answer questions generated by continuing controversy over hunting mourning doves during September. Adult mourning doves have been observed feeding and brooding fledglings on numerous occasions, but reports on the con istency and duration of this behavior have not been quantified (Nice 1922, Moore and Pearson 1941, Taylor 1941, Monk 1949, Webb 1950, Mackey 1954). Mirarchi and Scanlon (1981) observed that captive fledgling mourning doves became independent of parental care at approximately 18 days of age (3-7 days postfledging). The survival of those fledglings was educed markedly when both parents were killed prior to that time. However, the possible survival advantage afforded by he gregariousness of wild fledglings and differences in dependency on parental care between earlyand late-season nestings were not studied. We investigated (1) the length of time wild fledglings were dependent upon a parent(s) for food; (2) the extent that wild fledglings were brooded by, or roosted with, parents; and (3) the differences, if any, in behavioral interactions (feeding, brooding, roosting) between parent Funded by the Accel. Res. Program for Migratory Shore and Upland Game Birds of the U.S. Fish and Wildl. Serv. in conjunction with the Ala. Dep. of Conserv. and Nat. Resour. 2 Ala. Agric. Exp. Stn. J. Ser. 15-83354. J. Wildl. Manage. 48(1):1984 99 This content downloaded from 157.55.39.102 on Mon, 03 Oct 2016 05:11:48 UTC All use subject to http://about.jstor.org/terms 100 DURATION OF FLEDGLING DOVE DEPENDENCE * Hitchcock and Mirarchi Table 1. Behavioral categories used to define interactions between parent and juvenile mourning doves during observation periods, 1980-81.