Primary Coverts Research Articles

The molting of young Gray Starlings

1. The molting to adult plumage of three hand raised young Gray Starlings Sturnus cineraceus was observed.2. The plumage of the young is first grayish and turns brownish or even rustic before molting begins, which is about 40 day after hatching and about 20 days after leaving the nest.3. The wing quills of both sides are usually shed at the same time.4. The primaries molt from innermost (I) to outer ones, and the last one (IX) was shed 84 days after the first primary (in bird A). Possibly normal molting intervals were: more or less a week for I-II, III-IV, IV-V, V-VI, (VI-VII on one side) and about two weeks for II-III and (VI-VII on one side), VII-VIII and VIII-IX.5. The maximum body weights (measured in the evening) markedly increased before the molting of primaries, but minimum body weights (measured in the early morning) were rather constant. Thus the increased body weights have possibly been used for growing new quills (see Fig. 2).6. In the female observed which was rather ill-nourished, remolting of the primaries began in the regular sequence (with an overlap of the first and second molting). The intervals from the first molting of I primary to its second molting were 52 (left) and 54 (right) days.7. primaries was unsheathed after about a week of shedding and was completely grown in about 20 days. The rates of growth of unsheathed feathers were average 0.2mm per hour and 4-5mm per day.8. The primary coverts molted 2-8 days after the primaries with which they are growing together.9. The bustard wing molted during the later part of the molting period of the primaries.10. The molting of secondaries occurred 35-40 days after the shedding of I-primary and during the molting of V, VI primaries. Molting proceeds slowly from inner to outer secondaries, with the intervals of about 20 days (though within 10 days between III-IV) in an observed case, and two months from the molting of I-secondary to V-secondary.11. The tertiaries were shed after the molting of I-secondary, in a sequence of II-III-I, the interval having been 21 days for II-III and 10 days for III-I.12. The greater wing-coverts molted at the same time and irregularly, with no relation with the secondaries.13. The tail molt was commenced by the 4 central feathers and proceeded to outer ones.14. The main molting of body plumage began about 70 days after hatching and 30 days after the shedding of I-primary, first on the flanks and lower back. The molting of the crown to fore-neck and upper scapulars delayed most. The body molting was completed at about 120 days after hatching, but the last primary and secondary were completed at 130 and 140-150 days after hatching.15. No marked difference was noticed in the speed of molting by early (early July) and later (early August) young birds in captivity.

Distinguishing Juvenile from Adult Bobwhite Quail

years the data may provide justification for continued open seasons, despite poor hunting success early in the season. The separation of juvenile and adult bobwhite quail has been based primarily on wing-feather characteristics. Dwight (1900) apparently was the first to make an intensive study of plumage changes in quail. He reports that the two distal primaries in all quail and grouse are retained in the postjuvenal molt, but he makes no mention of how these feathers differ from those on older birds. Stoddard (1931) calls attention to the shape of the outer two primaries as a criterion for separating young (pointed) from older birds (blunted). Van Rossem (1937) reports that the juvenal primary coverts in native quail are retained until the first annual molt the second fall (about August). Leopold (1939) reports that the buffy fringe on the tip of greater upper primary coverts 1 through 7 (counting from inside--outward) provides the best means for identifying young of the year. Thompson and Kabat (1950) made detailed studies of the molt of bobwhite quail and enumerated some irregularities in e wing molt of trapped wild birds. Studies on over 11,000 quail in Alabama have shown that the degree of marking on these coverts and the pointedness of the outer two primaries vary sufficiently to introduce a small error in separating young from old. This condition led to efforts to improve further on techniques for recognizing young of the year. Results of that study are here reported. A total of 7,037 quail wings sent in by cooperators during the 1954-55 hunting season (Nov. 25--Feb. 20) in Alabama was examined for age-ratio data. The wings were received in special postage-reply envelopes. Age was determined by methods described by Stoddard, Leopold, and Thompson and Kabat. Young of the year were recognized by whitish or buffish tips on the coverts (Fig. 1), and by pointedness and slight fading of the outer two primaries. A fluorescent light was used to help distinguish the faded brownish color of the outer two primaries in young of the year. Adult birds were recognized by the even slatish gray coverts, and rounded tips and similar shading on all primaries (including Nos. 9 and 10). Even when all these characteristics were used, some quail could not be aged with accuracy because of the intergradation of characteristics. Such birds were recorded

A Field Technique for Bursal Inspection of Mourning doves

fully adult birds is referred to in this paper as young-adult. We call the other group full-adult. These age classes are readily separated in both species by differences in color and pattern of the upper primary coverts. Our data show the sexes in the two age classes to be distributed as follows: Gambel's quail: young-adult, 105.9 males per 100 females (270: 255); full-adult, 126.3 males per 100 females (120: 95). Scaled quail: young-adult, 90.2 males per 100 females (101: 112); full-adult, 143.1 males per 100 females (83: 58). We interpret these results to mean that, under natural conditions, a definite sex-differential mortality occurs, favoring males, in both Gambel's and scaled quail. Apparently, females do not fare as well as males in the struggle for survival. This probably accounts for the observed difference in relative numbers of males and females in the wild, although our data do not absolutely rule out the possibility of an original difference. The anomalous sex ratio noted for young-adult scaled quail almost certainly resulted from errors in sexing the birds. Live scaled quail are routinely sexed on the basis of slight differences in the color of the throat feathers. Ideally, in males these feathers are clear buffy, while in females they are grayish with faint longitudinal brown streakings. In full-adults these differences are usually very evident to a practiced eye. In young-adults, however, they are less definite and more variable, tending in general toward the female condition. This no doubt causes many errors in sexing scaled quail of this age class. That it is possible, nevertheless, to sex this species accurately by the method mentioned is indicated by the fact that one of the authors, after he had acquired several years experience sexing scaled quail, sexed a test series of 17 live birds without a mistake, as subsequently confirmed by dissection. Eleven of these were young-adults. Due to obvious differences between males and females in Gambel's quail of all ages except quite young birds, this species can be accurately sexed. Accepted for publication August 26, 1954.

Sex and Age Ratios among Bobwhite Quail in Southern Missouri

Howell County sample. From 1939 through 1943 the sexes and ages of 1,633 bobwhites bagged in Howell and adjoining counties were recorded. Sex was determined by the characteristic dimorphism of the head plumage. Young of the year (immatures) were differentiated from adults by the presence of the juvenal greater upper primary coverts and two distal juvenal primaries (A. S. Leopold, 1939). Determination of sex and age by these characteristics of the plumage probably is accurate within one per cent. The sample (Table 1) constituted the total bag of all hunting parties attended by the author, supplemented in 194143 by add tional birds killed by seven other hunters; most of these birds were kille w thin 20 miles of West Plains, Howell County. The cooperating sportsmen, selected for reliability and interest in the investigation, preserved separately the wings of cocks and hens. The age of each bird was determined later by the presence or absence of juvenal feathers in the wing. State-wide sample. In addition, statewide samples of the sex composition of the bobwhite population, and smaller samples of the age composition, were obtained in 1942 and 1943 from hunter kill-records (Table 2). Cooperating sportsmen throughout the state submitted tallies of their daily bags to the M s ouri Cooperative Wildlife Research Unit; these aggregated 20,179 and 23,640 birds, respectively, in the two seasons. Cocks and hens were listed separately. These records furnish a

Age Determination in Quail

In studying a bird species it is often of value to be able to segregate individuals into groups. Differential behavior of old and young birds and composition of populations cannot be determined unless classes can be recognized. This paper describes a method of determination, dependent on a peculiarity of plumage molt, that seems to hold for at least nine species of American quail. As used here, the term age determination means only the segregation of individuals into three principal classes-juveniles, young or immature birds in their first year of life, and adults. It is of course easy enough to recognize juvenile quail during the first few months after hatching, but in a winter population there are few differences between immature birds and old. Due, however, to an incompleteness of the postjuvenal or first fall molt, a few juvenal feathers are retained by immature quail throughout the first year of life, and the presence of these serves to differentiate young birds from adults. These feathers are the outer two primaries of each wing and all the greater upper primary coverts. It was early observed by Dwight (1900) that the postjuvenal molt was incomplete in all quail and grouse. He describes the retention of the outer two