April 17, 2013
April is the time when we start to hear some of Michigan’s 13 species of frogs and toads making noise. While the green frogs pictured above were confusing their Frogbook friends in July, most of the distinctive spring frog calls are males advertising that they’re looking for love. The Michigan frog & toad page from the DNR explains:
As temperatures rise in early spring, frogs begin to move to their breeding sites. The actual timing depends on the warmth of the air and water, and the humidity, but there is noticeable order in which the various Michigan species become active and begin voicing their breeding calls. For example, in southern Michigan the raspy voice of the Western Chorus Frog is usually heard first, often in late March, followed quickly by the highpitched peeps of the Spring Peeper. In a few days the woodland swamps are filled with the quack like calls of the male Wood Frogs, while in another week in open marshes the low snores of the Leopard Frog are barely heard over the squeaky songs of newly arrived Red Winged Blackbirds.
The first warm rains of April bring American Toads out of the woods to the breeding ponds, where the air is soon filled with their melodious trills. Several of our frogs postpone their breeding activities until later in spring, when air and water temperatures are higher. Included in this late group are the Gray Tree Frog, Blanchard’s Cricket Frog, and Green and Bull Frogs.
Frogs are far more often heard than seen. Most frog sounds are the advertisement calls of the males, intended to attract the females for breeding. Frog voices may carry for long distances, especially the higher pitched calls of the smaller species. The males increase the loudness of their calls by ballooning out their throats or special sacs at the sides of their throats, creating a kind of resonating chamber. Only males produce advertisement calls, but both sexes may give shorter warning calls or screams when danger threatens. Males can also produce distinct calls that warn away rival males that approach their calling or breeding sites.
Female frogs and toads may lay hundreds or even thousands of eggs. These are usually attached to underwater vegetation or left floating in large masses at the surface. During egg laying, the male clings to the female’s back and fertilizes the eggs. The small, dark eggs are protected by layers of a jelly like substance. They may be in rounded masses (as in Wood and Leopard Frogs), loose clusters (Gray Tree Frogs), long necklace like strings (Toads), thin surface films (Bull and Green Frogs), or deposited singly or in small clusters (Spring Peeper). Many frog eggs are eaten by predators such as fish, turtles, and aquatic insects, or are lost to drying or destruction by micro organisms.
April 16, 2013
Marty took this shot near Houle & Wilson in Menominee County in the UP. One of the commenters on his photo who grew up about 3/4 of a mile from there explained that the kilns were used by a sawmill for drying lumber.
More from Marty on Michigan in Pictures!
April 15, 2013
The Lyrid Meteor Shower at spaceweather.com explains that:
Every year in late April Earth passes through the dusty tail of Comet Thatcher (C/1861 G1), and the encounter causes a meteor shower–the Lyrids. This year the shower peaks on Saturday night, April 21st. Forecasters expect 10 to 20 meteors per hour, although outbursts as high as 100 meteors per hour are possible.
Lyrid meteors appear to stream from the bright star Vega in the constellation Lyra. In fact, Lyrids have nothing to do with Vega. The true source of the shower is Comet Thatcher. Every year in April, Earth plows through Thatcher’s dusty tail. Flakes of comet dust, most no bigger than grains of sand, strike Earth’s atmosphere traveling 49 km/s (110,000 mph) and disintegrate as streaks of light.
Lyrid meteors are typically as bright as the stars in the Big Dipper, which is to say of middling brightness. But some are more intense, even brighter than Venus. These “Lyrid fireballs” cast shadows for a split second and leave behind smokey debris trails that linger for minutes.
Occasionally, the shower intensifies. Most years in April there are no more than 5 to 20 meteors per hour during the shower’s peak. But sometimes, when Earth glides through an unusually dense clump of comet debris, the rate increases.
There’s no way of knowing whether or not this would be a big year, but I’d say that with the Iron Lady’s recent passing, there’s a chance! FYI, Comet Thatcher was named by A.E. Thatcher way back in 1861.
Nobody I know caught the Northern Lights Saturday night, but I thought that Cory’s photo taken when he went looking for Lyrids on April 22, 2012 would be the next best thing! Check it out on black and see more in his Space slideshow.
April 13, 2013
The Pictured Rocks National Lakeshore feature on the collapse of one of the two turrets at Miner’s Castle explains that 7 years ago today:
On Thursday morning, April 13, 2006, the northeast turret of Miners Castle collapsed. One turret remains on Miners Castle, the best-known feature of Pictured Rocks National Lakeshore. The collapse was reported via cell phone by fisherman in the area, according to chief ranger Larry Hach.
Most of the rock fell north and into Lake Superior, and there were no injuries. The lower overlook platform near Miners Castle appears to be unaffected.
While the rockfall at Miners Castle on April 13 was startling, such events are not rare along the Pictured Rocks escarpment. At least five major falls have occurred over the past dozen years: 1) two different portions of Grand Portal Point, 2) the eastern side of Indian Head just east of Grand Portal Point, 3) Miners Falls just below the (now modified) viewing platform, and 4) beneath the lip of Munising Falls (along the former trail that went behind the cascade).
All the rockfalls involved the same rock unit, the Miners Castle Member of the Munising Formation. Rock units are named for places where they were first technically described. The Miners Castle Member consists of crumbly cross-bedded sandstone that is poorly cemented by secondary quartz, according to U.S. Geological Survey Research Ecologist Walter Loope.
Rockfalls along the cliffs typically occur in the spring and fall due to freezing and thawing action of Mother Nature.
April 12, 2013
April 11, 2013
April 10, 2013
Crocuses have to be one of my favorite flowers. In addition to being beautiful, they are also one of the leading harbingers of spring in Michigan!