Author: Travis Runia
In part 3 of this 6 part series, we examined the details of pheasant ecology during July & August. Reproductive responsibilities for roosters are nearly complete by early July. By late July, they have replaced all of their feathers and even managed to gain weight for the first time in 5 months. This trend continues into August as these are easy times for South Dakota roosters.
Conversely, we saw hens reach their worst body condition of the year in August. Egg-laying, incubating, and brood-rearing responsibilities have been extremely energy demanding and decreased the amount of time she could spend foraging. These energy-demanding activities also caused her to delay her molt until July when more energy could be allocated to growing new feathers. Chicks have seen their own challenges as predation and other factors have taken their toll. Those that have survived to late August have been targeting protein-rich insects for food to grow tissue and feathers. In August, chicks begin replacing their Juvenile feathers with adult feathers which carry on their demand for protein-rich insects.
By September and October, the heat of summer has faded along with the struggles that went with it for pheasants. Temperatures have moderated and are well within a pheasant’s thermoneutral zone. In other words, pheasants do not need to use more energy to stay warm or keep cool when the air temperature is between 40° and 104° F. Along with the comfortable temperatures and long days of early autumn, abundant food is available through waste grains, weed seeds, and insects. This is good news for pheasants, especially hens which are in their worst body condition of the year coming into September and may weigh 25% less than they did last April.
Although abundant food resources become available during early fall, diet still varies considerably between cocks, hens, and chicks. Before we discuss why this variation in diet occurs, let us consider the differences in the nutritional content of the available food resources.
Corn and wheat are the primary waste grains available to pheasants during fall. One could assume these two waste grains would be equally nutritious to pheasants, but that is not the case. Corn contains 23% more metabolizable energy than wheat, but wheat contains 60% more protein than corn. Most weed seeds are highly nutritious with protein levels similar to or higher than wheat and metabolizable energy similar to corn. Foxtail grass, an abundant annual grass which frequents farm fields and disturbed areas are highly nutritious, abundant, and highly utilized by pheasants in autumn. Sunflowers, millet, and milo are also locally important food sources. Soybeans, although abundant and high in energy and protein, contain digestive inhibitors which render them nearly worthless as food for birds. Research has revealed that birds lose weight and become malnourished when fed soybeans. Protein-rich insects remain available through early fall until the first hard frost.
The completion of wheat harvest in August coincides nicely with the period when hen pheasants need protein and energy to recover from the demanding tasks of motherhood. Remember, hens are in their worst condition of the year in early September and still have to molt and regrow their feathers. Fortunately, chicks start leaving the hen at 10 weeks of age so by, September most broods are on their own. After nesting and brood-rearing responsibilities have caused hen pheasant weight to decline by 25%, September provides prime conditions to make up these losses before winter. Hens now have time to concentrate solely on feeding for the first time in five months.
Since wheat and weed seeds are abundant and a good source of protein and energy, hen pheasants target these food sources in September and October. Insects provide the highest protein content and are targeted as well. By mid-October, the amount of wheat available to pheasants has declined due to tillage or germination. Wheat seeds also deteriorate quickly when wet. Fortunately, hens finish their molt in October so her protein demand will decrease at the same time as wheat and insect resources decline. As corn harvest gets underway in October, the hen will consume mostly corn and weed seeds by late October. Corn provides more energy than the hen needs in October so she will gain modest weight for the first time in six months.
Pheasant chicks are experiencing life on their own for the first time in September. Although they still weigh less than their adult counterparts, chicks will consume just as much food as adults. Pheasant chicks still need a diet rich in protein to continue their molt and grow to adult size. Chicks will consume 2-3 times more insects and weed seeds and fewer waste grains than adults to meet their protein demand. By October, most chicks have reached adult size, but they are consuming more food than adults as the final stages of their molt require additional energy and protein. You may notice that hunter-harvested birds in October are in various stages of molting. Late hatched roosters are even hard to distinguish from hens. The age (in weeks) of hatch-year roosters in the bag can be aged by the length of their outer three flight feathers.
Adult roosters have had it easy since they finished their molt in July and this continues in September and October. Remember, they were able to molt earlier because they did not have any energy-draining motherhood responsibilities like the hens. Roosters began bulking up for winter in July, and their weight increase continues into early fall. Insects represent a smaller portion of an adult roosters’ diet than hens or chicks. Roosters only need protein for body maintenance and this can easily be supplied through weed seeds, wheat, and corn. The rooster’s diet mirrors what is available, but corn is preferred when corn and wheat are both available. Roosters continue to store fat reserves as winter is right around the corner.
In the next issue, we will examine how pheasants handle the first blasts of old man winter. As fall turns to winter, pheasants will need to change their behavior to conserve energy and stay warm and change their feeding habits as snow covers the once abundant food sources.