and an invasive one.
Katherine and I found ourselves recently driving up to see her niece in Healdsburg. Using eBird to find a hot spot on the way, we found ourselves at Las Gallinas Valley Sanitary District.
We parked, crossed a bridge over Miller Creek and walked along the first reclamation pond. This pond had small islands in the middle of it. On the beach of one of the islands, we saw a flock of White Pelicans, several Snowy Egrets and a swan preening itself.
“Oh, cool!” I thought. “A swan!”
I’d seen a swan for the first time (outside of a zoo, that is) in Thompson Falls, Montana recently. That had been a Trumpeter Swan. What kind was this?
I continued to walk around the pond. Near some reeds at the far side, I saw another swan with five juveniles.
They were so cute! I took several pictures of them and then concentrated on the parent. I wanted to make sure I had a nice clear picture for identification purposes.
When we got into the car, Katherine looked up Swans in Audubon’s Field Guide to California. She read that we have Tundra Swans in California.
Later, when I had downloaded the photos from my camera, I looked more closely at the swan. Is that a snail on its bill? I used the eBird Plus app on my phone to identify the bird: a Mute Swan. And that “snail” was a distinctive black knob on its bill.
The Field Guide had only listed Tundra Swans. I checked the range map. I didn’t see that the Mute Swan had much range: the coastal areas of the Great Lakes and along the East Coast. What was it doing here, in Las Gallinas Valley Sanitary District?
I searched “Mute Swans in California” on my phone. The first result was “California Invaders: Mute Swans.” This didn’t sound good! I opened the link and read more.
From the California Department of Fish and Wildlife regarding the impact of Mute Swans:
Mute swans are voracious feeders of SAV [submerged aquatic vegetation], with each adult swan consuming up to 8 pounds per day, and destroying much more in the process. SAV is an important part of aquatic ecosystems as it provides food and shelter for native waterfowl, fish, and invertebrates. By consuming massive amounts of SAV, mute swans negatively impact the structure and function of aquatic habitats native species depend upon. Additionally, mute swans are aggressive [emphasis added] towards other birds, as well as people. Mute swans disrupt nesting activity of native waterfowl by chasing birds from their nests and have been reported to physically injure, or even kill, other birds. Mutes swans have been reported to attack people and, in some cases, have critically injured children and pets.California Invaders: Mute Swans [Online]. Available at: https://wildlife.ca.gov/Conservation/Invasives/Species/Mute-Swan. California Department of Fish and Wildlife. (Accessed 8 July 2021.)
And, more importantly,
If you observe this species in California, please report your sighting to the CDFW Invasive Species Program, by email to Invasives@wildlife.ca.gov, or by calling (866) 440-9530.California Invaders: Mute Swans [Online]. Available at: https://wildlife.ca.gov/Conservation/Invasives/Species/Mute-Swan. California Department of Fish and Wildlife. (Accessed 8 July 2021.)
And that is what I did. I clicked on the link to the Invasive Species Program. I emailed them about the Mute Swan and its location.
The next day, I received a response confirming that my bird was, indeed, a Mute Swan and that the information I provided would be forwarded to the biologist working on the Mute Swan issue.
The California Department of Fish and Wildlife post says that these swans have been seen in Solano, Marin and Sonoma counties. However, a few weeks ago, when we met that birder at Natural Bridges who told us about the Osprey Nest, she also told us about a Mute Swan that had been seen in a pond somewhere along Swanton Road. She did not mention that this swan is an invasive species.
Katherine and I went looking for it a few days later but did not see it. So, it’s possible that one has made its way down here.
Or, that a Tundra Swan was misidentified. (According to eBird, a Tundra Swan was seen in Harkins Slough in December 2020.)
Be On The Lookout!
Kathy: Bird cop! Good job!