Spring Fever, The Next Cold Snap, Winter Fish Kill & March Madness

Spring fever is in full bloom. I've been stricken with the fever, but I will admit I am not ready. This feeling leaves me with some sort of yard clean up anxiety that I cannot completely comprehend. Maybe it's the fact that I just don't want to give up the snugness my winter hat gives me. Regardless, temperatures for the month of March thus far are way above average as one would expect, 7.4 degrees above the mean average (81-10) to be exact. Based on the temperature trend projected by Lezak's Recurring Cycle theory, this warmer than average trend should last until the end of the month when a few shots of colder air are likely.

(OSNW3 Weather Brief)
(OSNW3 March Observations)

(OSNW3 March 2012 Summary)
(click on graph for the month summary data - it will open a new tab/window)


These warm March conditions are emitting a false sense of season and the longevity of them allow me ample time to ponder the next potential cold snap. Following the temperature trends based on the LRC, temperatures should certainly cool off in Oshkosh near the end of March and again near the end of the first week of April. One more cool shot is likely during the middle of April (which is related to our coldest air of the season that took place in middle January) before another string of warm-ups. While it will be difficult to get daytime highs to dip below freezing, overnight lows could easily get that low during the time frames (give or take a day or two) mentioned above. Overall the LRC trends are not suggesting a regression from our early spring into a newly found winter scenario. The blasts of cooler air should be short lived.


The morning of Mar 14 I strolled along Lake Winnebago to catch a glimpse. I noticed thousands of birds thriving on the icy waters. I also noticed the seasonal winter fish kill along the shoreline. I shared the below photo of the dead to a couple friends and it led to a great learning experience.

(Lake Winnebago Icy Waters - Mar 14, 2012)

(Grundman Landing Winter Fish Kill - Mar 14, 2012)

*Dissolved oxygen levels depend on temperature, depth, productivity and fertility, and water movement. In almost any aquatic environment, fluctuations in natural nutrient cycles can create imbalances which lead to oxygen depletions and fish kills. Generally, these fluctuations are difficult or impossible to predict, but high nutrient levels from feeding or over-fertilizing almost always compound problems with oxygen management. More.

*When snow and ice cover a lake, they limit the sunlight reaching aquatic plants. The plants then cut back on the amount of oxygen they produce. If vegetation dies from lack of sunlight, the plants start to decompose, which uses oxygen dissolved in the water. More.

*Dead and dying fish are an ugly sight. Truth is, most species of fish are relatively short-lived and have a high rate of mortality. Even large fish, too large to be eaten by predators such as bass and pike, experience a death rate of approximately 50% per year. More.

Thanks goes out the Sarah Kriha and Mateo Chavez for discussing and educating me on the subject! Shortly after I posted the above information, Mateo Chavez hits me up with this gem.

March 14, 2012 at 3:52:32 pm
I sent your info onto Lake Winnebago Fisheries Biologist, and it turns out those were gizzard shad, which are a forage species, and reproduce in massive numbers. Here is his response to me..."The dead fish are gizzard shad, most of which have been dead for some time. This area is the northern fringe of their natural range, and they experience frequent die-offs in fall through winter due to colder water temperatures. This seems especially true during periods of rapid cooling. I was out on Lake Winnebago today for a brief period, and saw dead gizzard shad everywhere I went. This is a fairly common occurrence on Lake Winnebago and the upriver lakes." In other words, nothing to be worried about. Gizzard shad are a short lived species. A favorite food for bass, but those in the pic are on the larger end of their growth limits.


Kimberly Hageman is Surviving Oshkosh and she recently shared the OSNW3 blog with her readers. In the entry she brings the COOP Observer program to the forefront. Genius! Perfect time for a shoutout and to promote March Madness for CoCoRaHS. In Winnebago County we have 7 human observers. Two in Omro, one in Neenah, and four in the greater Oshkosh area. If we were evenly spaced apart, which we are not, that would give us one precipitation observation roughly every 37 square miles. If anyone out there has a slight passion for observing the weather and precipitation, please think about joining CoCoRaHS.

*There is always a need for a greater number of observations, as the saying goes "the rain doesn't fall the same on all". Due to the variability of precipitation, amounts measured can be quite different only a block or two away. The more observations, the clearer the picture, the better the understanding of where it did and did not rain.

CoCoRaHS - Community Collaborative Rain, Hail & Snow Network


Eleven days ago the front of the house had a winter wonderland feel. It now shouts spring. Vote YES on Apr 3, 2012

(FOH - Mar 14, 2012)