The Daily Bucket is a nature refuge.
We amicably discuss animals, weather, climate, soil, plants, waters and note life’s patterns.
We invite you to note what you are seeing around you in your own part of the world, and to share your observations in the comments below.
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January, 2018
Otto’s Marsh, Pacific Northwest
I was seeing unprecedented numbers of Trumpeter swans this year in Otto’s marsh, one of the largest wetlands on the island and the most visible from a public road. During the last days of December I was counting swans numbering in the 70s, an assemblage understandably flagged by eBird as being “rare for this location”. I took photos and submitted them. An expert western Washington birder came through the county at this time and counted 82 in this marsh, so my reports were independently confirmed.
The most I’d ever seen there before was last winter in December/January during our big freeze, when all ponds and wetlands froze over, and even this large marsh was largely ice. Even at their most concentrated, 52 was the maximum I counted in the winter of 2016-17. Once the weather broke and our surface water thawed, swans dispersed around the island. I saw the last ones at Otto’s on March 4 — they departed soon after for their summer breeding grounds in northern Alaska.
This year they returned on October 26, and their numbers grew throughout the fall, until the beginning of January. We had a brief light cold snap at the end of December, but nothing like last winter.
After being crowded into the center of the marsh and onto the neighboring field for a few days, the swans spread out over its 25-acre hummocky expanse and I was looking forward to seeing them, including two families with cygnets, in full view for more of the winter.
Imagine my surprise the next day when the marsh emptied of swans, and most of the mallards, wigeons, ringnecks and buffleheads. On the 10th, there was just a single swan standing on a submerged hummock.
On the 15th when I went by, there were 8 on the far periphery of the marsh. But my first reaction on seeing the marsh this time was: It’s really full! The next day there were no swans and just a few ducks.
After a long dry stretch, we got some substantial rain. Between Jan. 4-12 more than 2” fell. This may not seem like much but our total annual precipitation is only 22”. All that rain ran off the saturated ground filling up low spots like this wetland, making it at least a foot deeper, almost covering the hummocks. My hypothesis is that it’s too deep for either swans or ducks to forage in successfully. They are dabblers; you can see of one the swans bottom-up in the January 9 picture. This spot is not as suitable right now, and they have moved onto other wetlands and flooded fields. Across the road where runoff from Otto’s drains I counted ~24 in one, and a few miles further on, another 20 or so (those marshes are farther from the road and partially blocked by brush, so I can’t get as good a count, or photos). They are also showing up in fields, in groups of 6-20.
Another possible factor is food. Swans are really big birds and each consumes as much as 20 pounds of plant material a day. Between the steady foraging all winter and the smaller area submerged plants are accessible, it’s not surprising they’re on the move to richer sites.
Forage has become a major issue in general for this migrating cohort of swans, the Pacific Coast Population (PCP). Their numbers are increasing steadily, with the vast majority of them wintering on the agricultural fields of western Washington and lower British Columbia. Many farmers are not too happy with them (even less happy with the wintering Snow Geese). From 1968 to 2005 the PCP has increased by 5.5% a year, with the rate of increase slowing since then to 1.5% a year. The total wintering population is now 25,000.
However looking at the numbers and distribution of Trumpeters over the past two centuries, we can see that this recent resurgence is a drop in the bucket compared to their state before colonial expansion and development.
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Indigenous North American people hunted a few swans for food along with other waterfowl and local mammals, but with European colonization things changed radically. Between the wholesale slaughter of swans for their plumage (for hats) and skins (powder puffs) plus the destruction of their wetland habitat, by 1900 Trumpeter swans were nearly extinct — down to a few hundred. Starting with the 1918 Migratory Bird Treaty Act, a series of legislative measures, management plans and recovery efforts in the US and Canada has saved the species, although its numbers were so low when the population bottomed out there’s concern about their genetic diversity now.
Swan numbers are increasing but wintering areas are not what they used to be. Note that the entire Gulf Coast, Mississippi River, East Coast and California Bay area wintering grounds are gone. They are now crowding into a few small areas which may well max out. The Trumpeter Swan Society identifies several major challenges the swans now face in winter as their numbers recover, that didn’t exist before:
- Loss of wetlands and diminished quality.
- Loss of farm lands where crop residues have been providing important winter food resources.
- Powerline collisions that injure or kill swans.
- Fatal lead shot poisoning swans swallow pellets found in soil where shooting activities have occurred
Those problems are much greater on the mainland, and while there are orders of magnitude more swans still on the fields and ponds of western Washington, more are appearing on the islands these past few years. They are dispersing into whatever habitat they can find. We don’t have vast agricultural fields or many wetlands, but their quality seems to suit the swans. Otto’s Marsh has recently been tucked under the wing of our county Land Bank (sjclandbank.org/...) as an agricultural easement, and will continue to be available to waterfowl forever.
Meanwhile, the big flock of swans has dispersed from Otto’s Marsh for now. I check every day, and count anywhere from 0 to 12 there (sometimes a few are along the far edge). Part of my survey now is checking out the several other wetlands and fields where they are feeding in smaller groups. It’s always impressive to see them flying from one to another. This is their home for another few months.
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Major rain event headed our way this weekend, a classic winter Pineapple Express. After the past week of moderate precipitation — super windy instead — the fields, ditches, ponds and wetlands will get even soggier here in the Pacific Northwest. It’ll get warm though. There was a report of Chorus Frog ribbeting in yesterday’s Bucket. I’ll be keeping an ear out.
What’s up in nature in your part of the world?
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