A black bear with two cubs used to come regularly to my feeder east of Hinckley. On several occasions she showed up without the cubs. What did she do with them when she came alone? One bear that showed up had a light brown back. How rare is this?
A sow will often stash her cubs in a tree when she goes off to forage, according to DNR bear expert Dave Garshelis. When she returns she gives a special grunt that tells the cubs it's safe to come down. Regarding the two-tone bear: About 7 percent of Minnesota bears are brown instead of black. The one you saw might have been molting, and had old fur on its back and new black fur on its front and sides. Sometimes the new fur grows in darker than the old.
When fishing I have always wondered: How do leeches reproduce?
North St. Paul
Minnesota has many kinds of leeches, and all reproduce in different ways. For most, sperm are transferred from one leech to another in a packet. The sperm make their way to the eggs, which are inside the other leech, and fertilize them. Then the mother releases the eggs into a cocoon, which is attached to aquatic plants or submerged stones. Eventually the eggs hatch into miniature versions of adult leeches. Interestingly, leeches are hermaphrodites, with both male and female reproductive parts. That means each leech can be a mom and a dad (though not to the same offspring).
The area on either side of Interstate 694 by Rice Street puzzles me. The amount of reedy vegetation that appears above the water surface changes from day to day. Near the highway there are sometimes whole large tracts of tall plants evident, at other times none. What is going on?
The cattail marsh in the Grass Lake portion of Ramsey County's Snail Lake Regional Park is made up of numerous floating mats, says Ramsey County Parks natural resources manager John Moriarty. These mats can become dislodged by strong winds and move around the lake, changing the appearance of the lake. They tend to move around more during times of high water because they are less likely to be in contact with the bottom of the lake.
I was shocked when buying plants for landscaping to find potted tamarisk (not tamarack). In Colorado, where we used to live, the tamarisk is a noxious plant. It takes all the water from the soil and leaves a deposit of salts that kills surrounding plants. There are places in Colorado that are totally taken over by tamarisk. It is virtually impossible to eliminate them once they take over. Is this not considered a noxious plant in Minnesota?
The Minnesota Department of Agriculture, which regulates land plants, does not currently restrict tamarisk in Minnesota. However, DNR invasive species expert Luke Skinner agrees that this non-native woody shrub can pose problems. "We are aware of the problem and are looking at options to minimize the impacts within the state," he notes.
I noticed an equinox discrepancy in the sunrise/sunset tables in DNR fishing and hunting handbooks. According to the tables the 2006 spring equinox fell between March 17 and 18, not March 21. The fall equinox fell on September 26, not September 21. Is this caused by bending of the sun's rays by the earth's atmosphere, or are there other factors involved?
The confusion comes in the definition of "equinox." Many people think it means the day on which the length of daylight and the length of darkness are equal. In reality, it means the point in time each spring and fall when the geometric center of the sun is lined up with the equator. At the equinox we actually have about 10 more minutes of daylight than darkness in Minnesota. As you noted, the fact that the sun is a (large) three-dimensional object rather than a point and the fact that the atmosphere bends light contribute to the difference.
As I turned on our outside spigot to fill our dog's water dish, pieces of green leaves spilled out with the water. Another day it happened again, and amidst the leaves, a bee came whooshing out. Is the bee responsible for this?
University of Minnesota Extension Service entomologist Jeff Hahn thinks you encountered a leafcutting bee, a type of solitary bee. "These common bees cut half-moon sections from leaves and line cavities with them to form their nests," he replies. "This bee apparently thought the spigot was a fine place to nest -- until the water was turned on!"
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