Saving and protecting wildlife
Historically wildlife populations were kept in check primarily by weather, food availability and predation. With many influences of man on the landscape, wildlife in some instances, have flourished to nuisance levels by human’s standards such as White-tailed Deer and Canada Geese. Others have seen population declines for reasons unknown, thus the need for study of these species. Wildlife species that have seen these population declines for unknown reasons are called environmental indicators. For example, Bald Eagles among other raptor species saw declines in their population back in the mid 1900s and through intensive studies was determined that DDT was the culprit. If not for these efforts, Bald Eagles among other wildlife may have become extinct. Imagine the United States with an extinct species as its national symbol. Today other wildlife is experiencing population declines for reasons yet to be determined. Monarch butterflies are one and an effort to restore their habitat has been widely publicized and action taken nationwide through planting pollinator habitat.
Another species that has been studied intensively in recent years is the Lesser Scaup, a diving duck species commonly referred to as Bluebills by hunters. This name is derived because of the powder blue color of the bills of males. Iowa is one of the center spots for study of these species because during spring migration tens of thousands of Lesser Scaup congregate on pool 19 of the Mississippi River near Keokuk in March every year. This high concentration of birds makes it efficient to capture and mark, band, multiple individuals for study.
The birds are lured into swim in style traps in shallow areas of the river. Traps are checked by researchers and volunteers several times a day to remove captured birds. Each bird is processed which involves weighing the birds and placing a metal leg band on one of the birds legs. The bands are stamped with an identification number that will be with the bird for life. Instructions are also stamped on each band if it should be recovered. If a person recovers a band they can submit the birds ID number directly to the bird banding laboratory in Laurel, Md., via website along with the location of recovery and how the bird died. Once the data is entered a certificate of appreciation will be issued to the finder that has both initial banding and recovery information. This helps wildlife managers determine migratory routes, longevity and in the case of game birds harvest numbers. This helps in part determine seasons and bag limits for future hunting seasons. Some of the Lesser Scaup from this project banded in previous years have been recovered as far north as Alaska and as far south as Nicaragua. Most of these birds however stay within the Mississippi Flyway from the southern prairie areas of Manitoba and Saskatchewan to the gulf coast.
Historically one of the most sought after and hunted waterfowl, the Lesser Scaup has seen a steady population decline over the last 35 years. In the last couple of years this decline has seemed to stabilize. Recent studies released indicate several causes for the population decline. Contaminates, lower female survival and reduced recruitment due to changes in food resources and breeding ground habitat are to blame. There is a heavily skewed 6:1 male to female ratio in Lesser Scaup which may indicate female survival is much less than males. When females arrive on breeding grounds in the boreal forest areas of North America they are in poor condition and cannot produce eggs for nesting which lowers new recruitment into the population. Studying their nesting biology is difficult and cost prohibitive due to the remoteness of their breeding range. Other factors including predation, deaths from parasites picked up during migration periods. One of the common parasites causing significant die offs are Trematodes transferred through snails which is one of the foods Scaup eat. The parasites cause lesions in the intestine of the birds and cause death. Recent studies have shown that hunting mortalities are not additive to the long term population decline and it is suggested that more liberalized regulations might benefit the species. With additional interest in the species being hunted additional efforts and funding might be directed toward increased studies that will provide insight why the population has declined and ways to correct the problems. The population of the species is currently estimated at around 5 million continent wide which is right at the long-term average for the North American waterfowl survey.
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Yesterday marked the beginning of the Iowa spring Youth Turkey season which runs from April 8-16. Wild Turkey populations were eliminated completely from Iowa from the late 1800s to the mid 1900s. Restoration efforts hoped at a minimum to have just a self-sustaining population in Iowa. The birds were able to adapt to the changes in the landscape along with regulated harvests are now found throughout the state. Older generations today knew the landscape of Iowa absent of Wild Turkeys. Opportunities exist today that previous generations didn’t have pursuing Wild Turkeys. Not to mention the economic impact the sport has.
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TROUT RELEASE NOTICE! A reminder that the trout release Sand Lake date was changed from yesterday to Saturday, April 22 at approximately 11 a.m. This release will also be host to a fishing derby of sorts. The fish released will be a mix of approximately 1,800 Rainbow trout and 200 Brook Trout. Staff from the Marshall County Conservation Board will be on hand to give prizes donated by local businesses if anyone catches a Brook Trout between the release time and 2 p.m.
Mike Stegmann is the director of the Marshall County Conservation Board.