Last week, my friend Marcus Roening sent me an email. The subject line read, "Go Today! Ruff & Fantastic shorebirds at Cedar River mouth". I went. The bird in the photo is the Ruff. The first and only one I have ever seen. They are rare here.
Birdweb describes the odds of seeing one in Western Washington as rare during August, September and October, i.e. during migration. During the rest of the year, the chance of seeing a Ruff in our area is apparently nearly zero.
Typically, Ruffs nest in Northern Europe or Eurasia and spend their winters in places like Africa, Southeast Asia. or Southern Europe. If you are ever lucky enough to observe them during their nesting process, it will be a wonderful treat. Click Here to see a video displaying their very entertaining mating strategies.
Ruffs are shorebirds. We do not see a lot of shorebirds around Union Bay. However, many dozens of shorebird species migrate through the PNW. They often look somewhat similar and identifying them all can feel overwhelming, especially since we see them infrequently. So, I have taken the strategy of first learning the local shorebirds, that I see more often, and then incrementally working to understand how other similar-looking shorebirds are different.
For example, we have Killdeer here year-round. To my knowledge, Killdeer are the only species of plovers in the PNW that have two dark and distinct breast bands and that nest around Union Bay.
Here is another example of observing both a more common Union Bay shorebird, a Wilson's Snipe, with a less common Union Bay shorebird.
During Winter, the Wilson's Snipe is fairly common around Union Bay. Although they do blend in with their surroundings and they can be difficult to see.
This is a Long-billed Dowitcher. The first clue to it not being a Wilson's Snipe is the lack of a stripe down the middle of the head. You can read the story about these two birds in the post, The Unsnipe.
By the way, there is another shorebird species that looks even more like a Long-billed Dowitcher than a Wilson's Snipe.
Last week, while observing the Ruff at the mouth of the Cedar River, birders with scopes were comparing these two birds and making comments about tiger stripes.
It turns out that both of these birds are juvenile dowitchers. However, one is a Long-billed Dowitcher (LBDO) and the other is a Short-billed Dowitcher (SBDO). They are nearly identical. Even their bills can be the same length. The male LBDO's bill can be just as long as a female SBDO's bill. In both species, the females are typically larger than the males.
One of the birders, a particularly gracious woman, described reading Dennis Paulson's "Shorebirds of the Pacific Northwest" and how the book provided excellent diagrams, photos, and step-by-step descriptions of how to identify our PNW shorebirds. She explained how it really accelerated her knowledge of local shorebirds.
Looking through my camera, I did not see any tiger stripes. So, when I got home, I pulled out Dennis' book and found a diagram (on page 328) comparing the juvenile tertials of these two species. It helped. However, I still did not see tiger stripes. So, I asked my friend, Marcus, who first taught me about birds, if he could explain the tiger stripe comments.
Marcus circled the tertials on both birds and explained that on the SBDO the "tiger stripes" are not always stripes. Birders tend to use the phrase because it sticks in their minds and helps remind them to look for the irregular light-colored markings that sometimes may sort of resemble tiger stripes.
This quick depiction is an attempt to clarify how the tertials on these two juvenile Dowitchers differ. The first is similar to the Long-billed's tertial, i.e. the central area is consistently dark, while the second is supposed to resemble the Short-billed's tertial and shows lighter markings, if not exactly stripes, in the central part of the feather.
This discussion inspired me to wonder how all the wing feathers are arranged in a sitting bird. I had seen diagrams of feathers in flight, and the visible wing feathers on sitting birds, but I still could not picture where all the other wing feathers ended up.
My goal for the following diagrams is to communicate common concepts that I understand to be true for all birds. These sketches are not intended to represent all feather types or any specific bird species.
In the first figure, during flight, the coverts cover the connecting shafts of the larger flight feathers, kind of like shingles on a roof, to give the wing airflow integrity when extended.
I doubt that scapulars are considered wing feathers. They are attached to the body in the shoulder area, however, they cover a portion of the coverts so they do work together, kind of like good neighbors.
The second figure attempts to show the flight feathers beginning to slide under one another.
The most interesting part of the process is that the outermost primary feather, P10 in this example, ends up being the closest wing feather to the body when the bird is at rest. Immediately above, or outside, it will be P9, then P8, etc. This continues with the primaries being folded under the secondaries, and the outer secondaries under the inner ones, i.e. S1, under S2, which tucks under S3, and so on. Finally, the tertial feathers end up on top.
The bottomline is the positioning of flight feathers at rest, relative to the bird's body, is essentially precisely the opposite of their arrangement in flight. Depending on the bird, the tips of the longest primaries may or may not be exposed above the tail feathers when at rest.
A trusted source for this information is an excellent write up by David Sibley's in Bird Watching. Click Here to read it for yourself.
As Marcus pointed out to me, the ultimate result is that the majority of the critically important primary feathers have the greatest protection from UV light when the wing feathers are fully tucked away.
Another rule of thumb to use when identifying Dowitchers is that Short-billed Dowitchers are more likely to be seen in Salt-water environments i.e. surrounded by Salt. Long-billed Dowitchers are more likely to be found in fresh-water environments that are usually surrounded by Land. I use the S in salt and the L in land as mental reminders of these associations.
However, the photo from the mouth of the Cedar River, shows both species standing side-by-side in freshwater. This demonstrates that location is not a precise method of identification, and explains why the birders were still looking for "tiger stripes".
Another helpful method of identification is to listen to the different sounds that two species make.
Click Here to hear the higher-pitched sounds of a Long-billed Dowitcher on All About Birds.
Click Here to hear the lower-pitched sounds of a Short-billed Dowitcher on All About Birds.
In case you are wondering, Yes, I was disappointed to realize that the Short-billed makes the longer sounds waves and the Long-billed makes the shorter sound waves. 🤷 The opposite sure would have made a great memory aid.
On a more positive note, I believe Marcus identified every shorebird within sight or sound near the mouth of the Cedar River. I am lucky to be able to share the link to his eBird checklist from that day. It includes his very instructive commentary and Sandy Pringle's excellent photos. Thank you, both!
Click on the following link to enjoy:
The most wonderful part of nature is the endless opportunity to observe and keep on learning!
Have a great day on Union Bay...where nature lives in the city and black birders are welcome!
Larry
Going Native:
Each of us, who breathes the air, drinks water, and eats food should be helping to protect our environment. Local efforts are most effective and sustainable. Native plants and trees encourage the largest diversity of lifeforms because of their long intertwined history with our local environment and the local native creatures. Even the microbes in the soil are native to each local landscape.
I hope we can inspire ourselves, our neighbors, and local businesses to respect native flora and support native wildlife at every opportunity. I have learned that our most logical approach to native trees and plants (in order of priority) should be to:
1) Learn and leave established native flora undisturbed.2) Remove invasive species and then wait to see if native plants begin to grow without assistance. (When native plants start on their own, then these plants or trees are likely the most appropriate flora for the habitat.)3) Scatter seeds from nearby native plants in a similar habitat.4) If you feel you must add a new plant then select a native plant while considering how the plant fits with the specific habitat and understanding the plant's logical place in the normal succession of native plants.
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Keystone native plants are an important new idea. Douglas Tallamy, in the book "Nature's Best Hope, " explains that caterpillars supply more energy to birds, particularly young birds in their nests, than any other plant eater. He also mentions that 14% of our native plants, i.e. Keystone Plants, provide food for 90% of our caterpillars. This unique subset of native plants and trees enables critical moths, butterflies, and caterpillars that in turn provide food for the great majority of birds, especially when feeding their young.
Note: Flowering plants and trees, i.e. those pollinated by bees, are also included as Keystone Plants.
This video explains the native keystone plant concept in more detail:
https://www.youtube.com/watch?v=O5cXccWx030
The Top Keystone Genera in our ecoregion i.e. Plants and trees you might want in your yard:
Additional content available here:
https://wos.org/wos-wp/wp-content/uploads/2022/10/Native-Plant-Resources-10-7-22.pdf
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In the area below, I normally display at least one photo with each post to challenge us to know our native lifeforms.
Scroll down for the answers.
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Western Tiger Swallowtail: A butterfly most commonly seen around Union Bay in June and July. (I had to find some tiger stripes somewhere in my photos.)
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The Email Challenge:
In response, I have set up my own email list. With each post, I will manually send out an announcement. If you would like to be added to my personal email list please send me an email requesting to be added. Something like:
Larry, Please add me to your personal email list.
My email address is:
LDHubbell@comcast.net
Thank you!
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The Comment Challenge:
Bottom Line:
If you write a long comment, please, copy it before hitting enter. Then, if the comment function fails to record your information, you can send the comment directly to me using email.
My email address is:
LDHubbell@comcast.net
Larry
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