Monday, April 20, 2020

Cob-weaver came in the house, saying "Come quick, there is a big circle of crows in the sky!"  We all went outside and high, high in the sky were about 100 or more black dots.  Mosquito said, "Those aren't crows, they're ravens!"  And it was true.  High, high in the sky circling were over 100 ravens, cawing and spinning.  They call the formation they were in a kettle because it looks like a kettle of boiling water in the sky.   In the case of birds, mostly raptors, it can be used as a verb, as in "They are kettling," which is what I said.  When raptors kettle they are using thermals to move over long distances, typically during migration.  Vultures and condors will kettle over a carcass, but when you see large numbers, it is definitely during migration.  The ravens were using a thermal to move to a higher elevation, then moving out of the thermal and gliding over to the next one.  This saves flight energy.  Our ravens flew off to the east.  Maybe they will settle down in Salinas farms for the summer.

We do see an occasional raven over our house, but they don't live here.  Their close cousins, crows, live here in abundance.  They are the morning chorus, and our evening lullaby.  They live in our yard with our chickens. They sometimes act like chickens.  They come too when I call the chickens.  They also tell me what is happening outside.  I know when there is a hawk nearby and when its time to put up the chickens for the night.  They live together in families, helping and protecting each other, also arguing a lot with each other and with outsiders. I know they recognize me, even if I cannot tell them apart.

Garden math: Try to estimate the total number of individuals in a flock of birds by just looking at it.  Scientists often use estimates like this for counting large numbers of things, but if you want to use it in science you need to be accurate.  That takes practice.  You can estimate the number of insects in an area, or the number of seeds in a seed pack.  Check after by actually counting them to see if your estimate was close, or better yet, right on target.

Farmer Ladybug 🐞