Trumpeter swans take a time out
TRUMPETER SWANS currently breed throughout most of the western Great lakes region. That region includes the states of Minnesota, Wisconsin, Michigan, Iowa, Ohio and Canada provinces of Ontario and Maintoba. Some of these swans, a very few, have a GPS-GSM transmitters to record high resolution, high frequency location and related data to biologists. Data gathering is basic to help understand the life cycle of this majestic bird.
Every five years, Iowa biologists have conducted a swan nest attempt survey during the May to August time frame. During 2015, they recorded 49 nest attempts. In addition, to nest success, notes on the number of cygnets hatched and the number of cygnets fledged were documented. When 2020 data was reviewed, it showed a 142 percent increase with 119 nest attempts across 37 counties. Of those 119, 97 nests were successful with an average of 4.4 cygnets hatched per nest.
A majority of Trumpeter Swan nests are in north central Iowa’s lake and marsh habitats. However, swans are adaptable so it is possible to find them in many other locations. With the population expanding outside of the traditional prairie pothole region, the role of restoration versus natural recolonization is not clear. Captured cygnets being relocated to other open habitats may not be needed in the future if the birds expand ranges on their own.
The overall population will be monitored every year. Nest counts are on a five year rotation. If data “gaps” indicate a more intense survey is needed, the call from biologists and avid waterfowl watchers will go out to collect more information.
Today’s swan images are obviously not nest related. To see swans out and about in any area farm fields is totally random and not unexpected. Large waterfowl like these swans are hard to miss just because of their size. When snow cover and ice melting happen on area lakes during March, such as Green Castle or Sand Lake, many species of waterfowl will make use of these areas. Be sure to also check out habitat areas including Hendrickson Marsh and Otter Creek Marsh.
BABY BIRD NAMES can be confusing. And how some names came to be can be obvious or downright mysterious. One could use a generic term of “chick” to describe any young bird newly hatched and still in the nest. For songbirds, the baby is virtually naked upon hatching necessitating the need for a parent to keep them warm and dry. Waterfowl and others are hatched with a downy body covering that when dry, make the young critter appear as a fuzzy puff ball.
At various stages of growth, a young bird may be called a hatchling, then a fledgling when flight feathers are developed enough for clumsy yet adequate forays away from the nest. Juvenile is any bird in that awkward stages of its youth when not yet mature. Subadult is a name for immature birds that have left the nest, are largely taking care of themselves, and have not reached sexual maturity.
Within bird families, for instance chickens, young may be called poults, or cockerel (males), or pullet for females. A young crane is called a colt. For doves, the name squab is on the list. Ducks have ducklings and eagles have eaglets, geese have goslings. With wild turkeys, young are called poults but if the young is a male, it will be called a jake, and a female will be a jenny.
MARCH BIRD MIGRATION list will start a long list of avian critters to be on the lookout for. Waterfowl cannot resist the urge to follow the snow line northward as it melts. New and temporary shallow water areas tend to warm up quickly. Many invertebrate animals that waterfowl eat may be found in those shallow waters. Look for Gadwall, pintails, Green-winged Teal. Blue-winged Teal, Wood ducks, Redheads, Canvasbacks, and scaup. Many hawks such as red-tailed, Red-shouldered and Broadwinged will ply the airwaves. Robins average return is on or about March 8th. March will be a busy month with longer days and hopefully fewer snowy days.
OTHER MARCH HAPPENINGS to anticipate are some human meet and greet opportunities. The IOWA DEER CLASSIC will be held in Des Moines on March 5, 6 and 7th. This is always a big event featuring everything deer related you can imagine. Mother Nature’s cycles continue with Chorus frogs beginning to sing. Woodcock birds will be doing mating flight rituals over native grasslands. Mid month spring peeper frogs begin calling. Owls will be tending to their new nestlings. Beaver begin leaving scent markings near their ponded winter retreats. An lastly, Spring season arrives on March 20th. And daylight savings time begins March 14th, 2021.
OUR SUN, that orb earth rotates around from an average distance of 93 million miles, is nice to see, nice to feel its warmth again and comforting in knowing that earth’s annual pilgrimage toward Spring is inevitable. Our earth has gone through, and continues to do so, long geologic time frames of change. Plate tectonic forces are always at work. Volcanoes continue to expel heat and magma from deep under the crust. Earth’s continental crust undergoes slow weathering and erosion. In short, there is nothing new under the Sun.
A driving forces for all of the above are cosmic in origin. The Sun plays a key role on life on earth. Did you know the Sun has its own cycles? One cycle has an average 11 year phase known as the Schwabe solar cycle, that has ties to sun spots high and lows. And the radiation our Sun produces may vary even by a small amount that has huge effects on radiation outputs and thus energy received at earth’s surface.
There is also a decadal fluctuation of about 75 to 90 years (the Gleissberg solar cycle), and another called the Bond cycle of about 1,100 to 1,500 years. Mix all these together, say with a low sun spot cycle, and the solar wind will be somewhat weaker. During such times, more cosmic rays influence earth in the form or more cloud cover. If sun spot activity is at its peak, solar wind is stronger and helps to deflect cosmic rays, thus less cloud cover.
Other Sun cycle names have been given by astonomers. Cycle times are 11, 22, 87, 210, 1,000 and 2,300 years. All these cycles are superimposed over each other, at times amplifying and at times weakening the net effect. Our earth’s natural history during all of its past ages and in present day-to-day life, depends upon energy from the Sun. We need to be appreciative of its life giving rays. A more complete understanding of our Sun is also a fascinating aspect of natural history.
Garry Brandenburg is the retired director of the Marshall County Conservation Board. He is a graduate of Iowa State University with a BS degree in Fish & Wildlife Biology.
Contact him at:
P.O. Box 96
Albion, IA 50005