Breeding season

“ Conspicuous breeding activity occurs from the first third of May to the last third of June.
The Influence of Dominant Foraging Adaptation.—Five categories here considered reflect broad foraging adaptation: woodland species, taking invertebrate foods in the breeding season from woody vegetation or the soil within wooded habitats; grassland species, taking invertebrate foods in the breeding season from within grassland situations; limnic species, foraging within marshy or aquatic habitats; aerial species, foraging on aerial arthropods; raptors, feeding on vertebrates or large insects. ”

“ Though among wild animals—birds, mammals, and others—breeding ceases when Nature no longer supplies abundant food and warmth; in domesticated mammals and birds, artificially supplied with food and warmth, the breeding season is greatly extended and often made continuous, as, under the same conditions, it is in Man himself.
Evidence yielded by the vegetal world is less conspicuous, [485] for the reason that the cold which arrests reproductive activity also arrests individual activity: growth of the individual and multiplication of the race vary simultaneously with variations in the seasons. ”

“ The best breeding season is from the setting of Arcturus to the setting of Aquila, (May-July) because lambs begotten later are apt to be born runts, and weak. As a ewe is pregnant for one hundred and fifty days, this arrangement causes her to drop her lambs at the end of autumn when the temperature is mild and the grass is renewed by the first rains. During the breeding season the flock should drink only the same kind of water, since a change not only makes spotted wool but injures the offspring. ”

“ The breeding season begins in April or May, when the courtship of the little creatures commences by a persevering pursuit of his intended partner by the male. The lady exhibits a becoming coyness, leading her suitor a long chase through the water ”

“ The breeding season commences in April. The nest is generally placed in the grass or amongst a group of plants, and is built of straw and dry leaves, lined with hair and other elastic materials. The eggs, from four to six in number, have a delicate pale grey or dirty yellowish shell, marked with dull purple spots, veins, and lines that are very close together at the broad end. The young are fed upon insects, and are fully fledged by May, when the parent birds at once proceed to undertake the care of a second family, only joining the rest of the flock when the work of incubation is completed. ”

“ In the region of my study the prairie vole breeds the year round, but the rate of breeding changes continually. There is no regularity in the trend of the breeding season from year to year. It is obvious that the species is responsive to environmental changes and is so well attuned that its breeding is speedily initiated or inhibited by changes to favorable or unfavorable weather. The incidence of breeding is highest when temperature is moderate and both water and foods of preferred sorts are plentiful. ”

“ The wise poultry keeper will not delay getting things in order for the breeding season. New blood is necessary to keep up the vigour of the flock. Buy 22 the best male bird you can afford. The rooster is more than half the flock. A good bird will grade up young stock next spring. Remember even if you have pretty good birds of your own rearing, there is danger in inbreeding for more than one season.
Select only the largest, brightest hens for the breeding pens. ”

“ It breeds twice during the summer, and returns southward in the beginning of autumn, in small parties, shifting chiefly by night. During the breeding-season, this little bird, when approached, shews great anxiety for the preservation of its eggs or young, and tries, with all the artifices employed by many other species, to entice the aggressor away from its nest. ”

“ From the time of emergence in spring, males show some tendency to seek out females, and frequently a pair may be found together under the same rock, weeks before the onset of the breeding season. There is no satisfactory evidence that such associations have any [46] permanence. At the time of emergence from hibernation the males rarely have even a trace of reddish coloration on their heads, and more than a month normally elapses before attainment of breeding coloration. ”

“ We feed them principally on hay and barley, increasing the ration at the breeding season so as to infuse strength into their get by means of their food. The breeding season is the same as for horses, and, like them again, we have the jack handled by a studgroom.
"When a mare has dropped a mule colt or filly we bring it up with care. Those which are born in marshy and swampy country have soft hoofs, but if they are driven up into the mountain in summer, as we do at Reate, their hoofs become hardened. ”

“ At Duenas he found it breeding in large societies, usually selecting the willows that grow near the lake and the reeds on the banks for its nest. The breeding season extends over some length of time. In May, young birds and fresh eggs may be found in nests in the same trees. On the coast, young birds, nearly capable of flying, were seen in the early part of March. ”

“ Woodland birds, aerial foragers, and birds of South American evolutionary stocks breed after temperatures surpass 70°F. on the average. Almost all such species are migrants, but many migrants have different temporal characteristics, and the categories thus are shown to be discrete on the basis of temperature at time of breeding. [Pg 595] The change through spring and summer of temperature and precipitation delineates the inception and waxing of the growing season of vegetation and of the subsequent arthropod populations, on which most of the birds feed in the breeding season. ”

“ They, however, raise only one brood in the season, unless their eggs or young have been destroyed. Should this happen, the female soon finds means of recalling her mate from the flock which he has joined.
On having recourse to a journal written by me at Henderson nearly twenty years ago, I find it stated that the attachment of a male to a female lasts only during one breeding season; and that the males provide themselves with mates in succession, the strongest taking the first choice, and the weakest being content with what remains. ”

“ The breeding season of this little Tit commences about the middle of March and continues throughout April and May. The nest is a lovely little ball of moss, mixed with cobwebs, lichen and seed-down and is thickly lined with soft feathers or with feathers and seed-down mixed. ”

“ A simple and probable explanation of the phenomenon is this:—When Starlings rear two broods in the year, the second brood would be younger than the first by some two months or so. When the breeding season comes round in the following spring, the second broods are not sufficiently adult to breed, and, not having any duties to call them elsewhere, they naturally continue to resort at night to the old familiar roost. ”

“ Its favourite breeding-places are in the Denny and Bratley Woods, Sloden, Birchen Hat, Mark Ash, and Prior’s Acre. Several nests are yearly taken, for the bird generally breeds when the bark-strippers are at work in April and May. A series of its eggs, in my collection, taken in the Forest, show every variety of colouring from nearly pure white to richly blotched specimens.
In the breeding-season the birds are excessively destructive. ”

“ The nestlings are fed upon insects and milky grains of corn. The breeding season lasts from April to August, and each pair rears two families during the year, building their nests in holes of trees, or occasionally in convenient nooks in houses or out-buildings; in structure they are like those of other Sparrows. ”

“ Of course, the breeding season is past a long time now, 164 and maybe if we keep our eyes open we'll be able to see a nest and get it for you to take home with you, though often they're in a place where it's mighty hard to get at them. ”

“ The breeding-season is at its height in December, and by the end of the month the young are generally capable of providing for themselves; they then assemble in vast flights, preparatory to their great migratory movement. The eggs are three or four in number, pure white, nine lines long by seven lines in diameter, and are deposited in the holes and spouts of the gum-trees without any nest. ”

“ Their time of breeding is according to the climate in which they reside: in North America, they breed in summer; on the other side of the line, they take the most favorable season of the year. They build their nests in extensive marshes, and where they are in no danger of a surprise. ”

“ They often do not inquire whether as a matter of fact any eggs were laid at the date when the frost occurred, they seldom support their statement by pointing out nests deserted by the hen after being buried in the snow, they keep the plausible explanation ready for use if required, and if the stock after all proves to be up to the average, they feel secretly rather surprised, but say nothing about the adverse conditions in the breeding season, for the excuse may be required the following spring. ”

“ Beginning at 2, 3 or 4, according to circumstances, the cycle may be repeated one or more times within the breeding season, or a new cycle may be begun, and stayed at any step from nest-building to laying of the eggs. Again, an entire cycle may be brought near the close, and then scamped, the young being left to die. ”

“ They live both on the central, higher rocky land and near the sea-cliffs, and, from being exceedingly shy and timid, seldom appear in the lower and cultivated districts. They are said to produce from four to six young at a birth, and their breeding season is in July and August. ”

“ Nevertheless, it cannot be said that the winter or summer area of every species is entirely unsuited to its requirements at other seasons, for some individuals pass the winter season in areas that are frequented only in summer by other individuals of their species. Such species have extensive breeding ranges, presenting wide climatic variations, so that some individuals may actually be resident in a region where others of their kind are present only in winter. ”

“ In order that it may be unnecessary to open colonies during a period of such unsettled weather as obtains at this season, it is advised that the room for breeding be provided in the fall and left with the bees all winter. ”

“ Suppose, therefore, we leave from thirty to fifty pounds of honey in the hive, is it not evident we have trenched that amount of space upon the breeding territory? Then, if the season is a good one for honey, this room is constantly being diminished by the bees depositing honey in the cells as soon as the brood leaves, the result of which will be your young swarms will be too small, and by winter the old ones, for the want of breeding room, are too few to raise sufficient animal heat to winter. ”

“ The sexes pair in the autumn, and the female, by means of her ovipositor, lays her eggs in some cleft or hole in the soil and leaves them to their fate. After breeding, the parents die with the autumn cold; but the eggs retain their vitality through the winter and hatch with the warmth of spring and early summer, the young gradually attaining maturity as the latter season progresses. ”

“ Breeding may begin in late January, and most females are in breeding condition within the first half of February. In oestrus the genitalia are enlarged and discolored and the vaginal orifice is prominent and gaping. By February most females born the previous season have matured, and breeding involves the entire population, except possibly for retarded young and individuals suffering from disease, injury or malnutrition. ”

“ Farther south in the species’ range with a much longer growing season, there is perhaps some possibility of such early breeding by first-year individuals. This would reduce by more than half the length of time required for a generation, and would tremendously increase the reproductive potential. With such added impetus to its reproduction the species might be able to withstand greatly increased predation pressure, or other mortality factors. ”

“ The actions of the birds themselves lend some support to this theory, as every bird student has noted the feverish impatience with which certain species push northward in spring, sometimes advancing so rapidly upon the heels of winter that they perish in great numbers when overtaken by late storms. It is probable that at this season the reproductive impulse is a determining factor in driving the birds to their northern breeding grounds. ”

“ It is possible that the length of the period may be increased by a second litter from the earliest breeding females in summer, but the large percentage of nonpregnant or nonbreeding animals which occurs throughout the season would indicate a wide variation in the time of breeding of different individuals. ”

“ Breeding schedule.—The 118 records of breeding span the period May 11 to August 10 (Fig. 8) ; the modal date for completion of clutches is June 5, and 45 per cent of all eggs are laid in the first ten days of June.
Number of eggs.—Clutch-size is 4 eggs (4.1, 3-6; 41) . Clutches laid at the peak of the season average 4.3 eggs (3-6; 26) , and replacement clutches average 3.8 eggs (3-4; 9) . [Pg 644] Nests are hung about 15 feet high (ranging from six to 55 feet) in elm, cottonwood, hackberry, locust, catalpa, willow, alder, osage orange, walnut, pear, linden, and ash. ”

“ Although gonadal response and seasonal restriction of breeding are set by the photoperiod, specific temporal relationships are dictated by more immediate environmental variables.
Table 9.—Relationship Between Environmental Factors and Timing of Breeding in Birds of Kansas
Table 9, as already noted, shows the gross relationships between certain groups of birds, certain arbitrary indicators of seasonal temperature-humidity conditions bearing significantly on the growing season, and occurrence in time of peak of egg-laying by the birds involved. ”