Monday, March 21, 2011

Monday Phenology: March 21, 2011

Posted by Kirk
Happy Spring! The vernal equinox arrived this weekend and this is the day many people use to mark the first day of spring. Technically speaking, we're half way between the winter solstice and the summer solstice. The equinox is the day with equal amounts of day and night. You'd figure that means 12 hours of daylight and 12 hours of night but let's look at the numbers.

Sunrise this morning was at 7:14 am and sunset will be at 7:26 pm. That's 12 hours, 11 minutes and 43 seconds for the length of the day. On the actual solstice, yesterday, the length of the day was 12 hours, 8 minutes and 35 seconds. Huh? If the day is more than 12 hours long then how is it the solstice? The answer is that we get some bonus sunlight. The earth's atmosphere acts as a lens that bends light allowing the image of the sun to appear slightly before it actually rises above the horizon and linger a few minutes at the end of the day after it has actually set. It may just be a trick of optics but I'll take the extra 8 minutes.

Here's what happened last week.

On Monday I got word that Penelope in Northfield spotted a Lesser scaup on the Cannon River. There were also reports of Peregrine Falcons returning to both Winona and Lock & Dam #1 in the Twin Cities.

Tuesday the maple sap really starting to run. I heard Sandhill Cranes again and Canada Geese flying overhead all day. Many area lakes had Canada Geese standing on the ice. We also had the first real rain of the season in the afternoon. Trees put out maybe a gallon of sap on average on Tuesday.

Wednesday started with thick fog in the morning with as little as 100 foot visibility in some spots. Smelled another skunk, the second of the season. A Barred Owl showed up near the nature center building but didn't come quite close enough for good photos. Wednesday I saw my first house fly of the year. I got word in the afternoon that naturalists at Belwin Outdoor Science (a.k.a. Valley Branch ELC) in Afton reported hearing the first Eastern Bluebird call of the season. There was also a report of a bluebird in northern Washington County but when I went for a hike I didn't see any.

Thursday was a morning when it really felt like spring was breaking the hold on winter. There were geese on many frozen lakes. Long strings of 40+ geese were migrating north in the morning light. The first of the year Great Blue Heron appeared in a lake next to the nature center. Later in the afternoon I saw a lone red-winged blackbird, my first of the season.

Friday was another nice day as was Saturday. I worked on Saturday teaching maple syrup programs. The sap wasn't running in the morning but by the afternoon when things warmed up the trees were gushing sap. I saw the first chipmunk of the season out and about and on my way home I snapped photos of the first Northern Harrier of the season. Word also came in that folks down at the Birds and Beers gathering in Winona saw a migrating Eastern Meadowlark fly overhead and there were Hooded Mergansers, Common Mergansers, Ring-necked Ducks and White Pelicans on the river. Tundra Swans were migrating overhead as well.

Sunday I helped put up a new Woodduck nesting box at my parent's lake. Woodducks are just starting to come into the state and are already looking for territory and next sites. The ground is thawed out enough to dig holes so if you were thinking about putting up a next box do it now! While putting up the box I saw two more Great Blue Herons. I thought I might have seen an Osprey near Flying Cloud Airport in Eden Prairie but didn't get a good enough look to say for sure.

This week:
This next week should be interesting. We've started to see new birds arriving here and there. Some of them are the advance guard, the early birds if you will. We should see more of the same this week. More geese, more cranes, more blackbirds, more bluebirds, more woodducks, more herons etc. Today will be beautiful but we're headed into more cold for the rest of the week including a good chance for snow on Tuesday/Wednesday. It will be interesting to see if the snow deters the birds. I'm thinking it won't have much effect in the twin cities as the real heavy snow (up to a foot) will be to the north. The big story this week will be flooding. Rivers across the state are rising and with more melting plus rain coming this week conditions will worsen. A new forecast came out this week which finally pegged down Friday, March 25th as the official day the Mississippi will enter flood stage in St. Paul. I'll have a more detailed breakdown of the flood forecast in St. Paul tomorrow.