I know you want me to show you bird stuff first!
click here to listen (it's a m4a file, but I can play it with Windows Media Player).
Orange-crowned Warblers are always nice -- one of the treats of late fall.
We catch very few Yellow-bellied Sapsuckers -- this is the 6th in over 20 years -- so this youngster was fun to see. Woodpeckers tend to hammer on your fingers, and the very fine, chisel point of a sapsucker bill is an effective weapon...
...although nowhere near as formidable as the powerful bill of a Rose-breasted Grosbeak. We always give grosbeaks a lot of respect!
One thing we always look at when trying to determine the age of birds is whether there is contrast between old and new feathers. In the photo above, it's easy to see the four paler, more worn wing feathers, which she has not replaced this year, and how they contrast with the new, fresher, darker wing feathers. The new feather in the middle that is a bit shorter is still growing in.
Onto the fruit. Our analyses of seeds found in the fecal samples of birds requires context: some sort of compilation and rank abundance of all the ripe fruit available to birds to eat when they are present in the area. Each year, we estimate the percent of ripe fruit on the common species once a week or so throughout the season. This year we are making sure we have complete data on all fleshy fruits available, even if they have not shown up in fecal samples -- all together around two dozen species. For less-common fruits, we have tried to locate and count all individual fruit, once a week. For abundant species, we cut down branches, counted all the fruit, and came up with an average for a "representative" branch. Then we go out and count the number of representative branches each week in a 200 meter circle centered on our banding area.
I can tell you that this work falls under both "tedious" and "easier said than done." It is not precision work (and it varies annually depending on fruit crop), so what we'll end up with is a list in approximate rank abundance, based in categories that increase by orders of magnitude. Even with that crude ranking, it's not easy and very time consuming. Much of our counting is done along a busy public bike path. People are intrigued when they see one of us standing and staring at the vegetation for long periods of time; they inevitably ask us what I am looking at. I know I have become much more adept at writing down my fruit counts and keeping track of where I am so that I can stop and explain what I'm doing.
|How many ripe multiflora rose hips are just |
in this one bush?
We start on Monday, spend at least one full day just working on fruit, and finish as best we can on days we band. Due to our funding shortfall, our days have been cut back so we are cramming as much work in as possible.
These tasks would not be possible without the help of Dana Wloch, who first started with RRBO as an undergrad, then under several grants, including one where she helped develop our seed identification website, and now is back as a volunteer. Thank you, Dana! We are the dynamic fruit duo of Dearborn.