September 2006





How will the dry conditions we experienced this summer impact fall colors? What will the colors look like?

Fall colors vary from year to year and place to place for several reasons. Weather is most critical in determining the colors displayed each fall. Colors are best when high quality foliage - a product of a warm, moist summer - is exposed to sunny, cool fall days. Light frosts may also help, but hard freezes can ruin the display. Physiological stresses placed on trees can impact fall colors. Cool, wet summers can cause premature displays of color. A mild summer drought may actually increase the display, but severe drought usually dulls colors noticeably. In some cases, foliage may die early and turn straw-colored due to a lack of water. Because it is too dry to produce the vibrant reds, yellows, and oranges, the severe summer drought will create a landscape filled with the subtler colors of tans, bronzes and auburns.

Jana Albers, DNR Forest health specialist, Grand Rapids


Although the loon is a bird, it differs from songbirds and waterfowl. How?

The bones of most birds are hollow and light; however, loons have some solid bones that make diving easier but flying more difficult. This extra weight enables them to dive deep - in excess of 100 feet - to search for food. Once underwater loons can remain there for several minutes. Even though loons are capable of diving deep and for long periods, most dives are shallower and shorter. Because their bodies are heavy relative to their wing size, loons need a runway of 60 or more feet in order to take off from a lake. When airborne loons can fly more than 75 miles per hour. Another unique characteristic of a loon is its legs. These extremities are set far back on its body, which means a loon cannot walk like other birds. If on dry land, a loon must push itself along on its chest.

Pam Perry, DNR Nongame Wildlife specialist, Brainerd


The DNR has drafted a new plan to improve ruffed grouse hunting in Minnesota. But with grouse populations regulated by a natural 10-year cycle, how much influence can man-made actions have on grouse numbers?

Human activities can exert a tremendous influence on grouse populations through land use practices and habitat management. Although humans do not have much effect on the existence of cycles in ruffed grouse populations, we can affect the population size around which the cycle oscillates. The quantity and quality of habitat can limit how large grouse populations will grow. Converting all the forest in an area to pavement would certainly result in the loss of grouse in that area. On the other hand, increasing the area of forest, or the quality of existing forest, for ruffed grouse in an area that currently supports a grouse population would benefit those birds. Doing this would allow a grouse population that currently cycles between 500 and 1,000 birds to cycle between 700 and 1,400 birds.

Mike Larson, DNR grouse research biologist, Grand Rapids


The DNR has been aggressively reintroducing sturgeon to Minnesota waters, especially in the Red River Valley. What is the purpose behind this work?

Until the late 1800s, lake sturgeon were abundant in the Red River basin. However, the construction of dams, decline in water quality, loss of critical habitat, and over harvest eventually took their toll, nearly eliminating the sturgeon from the basin. DNR Fisheries annually stocks 200,000 lake sturgeon fry and 10,000 fingerlings into Red River basin waters as part of a comprehensive program to re-establish lake sturgeon populations in their native range. At the same time, DNR Fisheries and Ecological Resources are actively working to remove fish passage barriers that prevent sturgeon from accessing historical spawning areas. The goal of the program is to establish a sexually mature, naturally reproducing population over the next 20 to 30 years - the length of time it takes for female sturgeon to reach sexual maturity. On a broader scale, lake sturgeon recovery efforts in the Red River basin are part of an overall long-range goal to protect, enhance and re-establish lake sturgeon populations in Minnesota and its border waters.

Tom Groshens, DNR Red River Fisheries specialist


DNR Question of the Week Archive