Instead, I created a new spreadsheet, and manually copied the data from the annual bird reports into it. It is not that time-comsuming, but it does introduce a possible sourse source of error - oops!
There are tabs in the new spreadsheet for all the charts below.
I created charts showing the average count per species, mostly grouping the birds as in the annual reports.
I didn't do a Raptors chart; the osprey and the red-shouldered hawk are our most common, but they only average 1-2. I included the smallest raptor, the loggerhead shrike, in with the common passerines, together with the blue jay, which was grouped with the corvids.
- Swimmers. Muscovy ducks, steadily down. Gallinule, steadily up. The high number for the mottled duck in 2023 may be from multiple observations of clutches of ducklings - up to 12 ducklings. These seem to undergo fairly rapid attrition - the following week there will be 7, the week after that 3.
- Divers. Note, we have 3 divers from the surface of the lake, & 2 divers from the sky. The peak in cormorant numbers in 2021 prompted me to worry about a Cormorant Menace.
- Divers, Migratory
- Waders. The Wood Stork is different from the rest of these in that he feeds more like a dabbling duck: stick that huge bill into the water, swish it around, eat whatever's left. The others are visual hunters who spear or grab prey with their beaks.
- Ibis. These are kind of waders, but tbey forage in front & back lawns just as often. They feed by sticking their bills in the ground & wiggling them. Anything wiggles back, chomp! Plus their numbers are larger than the true waders.
- (Passerine) Birds Observed > 75% of the Time.
They should be easy to keep updated.
Here's the home page/directory for my posts on Birdwatching in IslandWalk.
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