Last month, The Cornell Lab of Ornithology published a comprehensive study showing that the bird population across North America has dropped by 2.9 billion breeding adults since 1970. A few weeks after Cornell’s study came out in Science magazine, the National Audubon Society published their own: “Survival by Degrees: 389 Bird Species on the Brink.”
While Cornell’s study looked back at the past 50 years, Audubon’s study looked ahead to 2080, and the possibility of unmitigated climate change. The study calculated the future of bird habitats with data collected from 140 million observations of current bird populations and climate model projections for three levels of temperature rise: 1.5, 2 and 3 degrees Celsius. The scientific consensus is that only immediate action will hold temperature rise at 1.5 degrees Celsius, and that without action the globe could see an increase of 2 degrees by 2050 and 3 degrees by 2080.
Ann Brice, president of the Yolo Audubon Society and member of the California Audubon Board of Directors, describes the society’s new study as, “depressing, but also hopeful.” She spoke with the Express in a phone interview about what the projections mean for bird populations in Yolo County.
“Survival by Degrees” predicts that more than 74 California bird species will be made highly vulnerable by a temperature change of 3 degrees Celsius. In Yolo County, there are 19 species that would qualify as highly vulnerable under these conditions, and 45 that would be moderately vulnerable.
Even common Yolo County birds, like the California quail and the yellow-billed magpie, could be a rare sight in 2050 and nonexistent in the region by 2080.
The National Audubon Society has created an online tool that allows people to see how projected climate change will affect North American birds’ range. Looking at the yellow-billed magpie, in the current climate the species lives in the Sacramento Valley and down a small corridor that reaches the Pacific Coast. At an increase of 1.5 degrees Celsius, the birds might still reside in Yolo County, but they have lost 69 percent of their range area. At an increase of 2 degrees they lose 82 percent of their range. If the global temperature rises by 3 degrees Celsius, 100 percent of their range is lost.
But there is cause for hope, Brice says. In an email to Audubon members Andrea Jones, the director of bird conservation for Audubon California, says, “The most important takeaway from Audubon’s new climate report is that if we take aggressive action now, we can help 76 percent of vulnerable species have a better chance of survival.”
Changes in Yolo
Yolo Audubon Society has been conducting long-term ecological studies to follow bird populations in the area. Twice a month a group goes out to Bobcat Ranch, located northwest of Winters, to observe the ecosystem and tally bird populations. It’s a small thing, Brice says, but that’s what it takes.
It can be difficult to draw a direct connection between climate change and species collapse, Brice says. She gives the example of the burrowing owl. We know that this population is declining, and we know that habitat destruction is at least partially driving it. Is that habitat destruction directly tied to climate change? That is harder to determine in the present. The destruction could be due to human development, or weather phenomenon in a certain year.
Brice explained that it’s easier to make these kinds of direct connections in hindsight, often when it’s too late.
But by collecting large amounts of data over many years they are able to spot trends and make broader connections. Long-term observations allow them to compare bird’s migration patterns and blooming periods of native plants. As the climate changes and these natural cycles are thrown out of whack, the flora and fauna face a missed connection that affects the rest of the ecosystem. Without the blooms, the birds change their migration pattern. Without the pollinators, the plants suffer.
There are other ways that Yolo County has already seen the effects of climate change. Brice notes that there has been an increase in populations of southern hemisphere birds, like the great-tailed grackle. While they used to be a rare sight, they have become common in the previous decades.
Brice says that birds like the grackle are of particular interest to scientists because of their ability to adapt to new environments. As they expect to see more populations move north to cooler temperatures, researchers want to know what allows certain species to thrive as others fail.
Human solutions to human threats
Brice says that cultivating interest in these species can be a force to preserve them. Appreciation for these species causes people to understand the grave importance of preserving their habitats.
One way the Yolo Audubon Society cultivates that appreciation is hosting the Putah Creek Christmas Bird Count. This annual event has been running since 1971 and is a part of the National Audubon Society’s annual Christmas Bird Count, the world’s longest running citizen science survey. For a few weeks in mid-December recreational birders and researchers step out into nature and add to a running census of birds.
Yolo County’s count covers a 15 mile radius that centers around a point just south of Winters. This year the count will take place on Sunday, Dec. 15. For non-birders who want to participate there will be a workshop on finding common Yolo County bird species on the first Wednesday in December.
Participating in citizen science like the Christmas Bird Count is one of seven ways that Cornell University suggests for helping bird populations. They also suggest:
- Making windows safer for birds
- Reducing plastic use
- Buying shade-grown coffee
- Reducing lawns and planting native species
- Avoiding the use of pesticides
- Keeping cats indoors
Brice also recommends keeping cats indoors to protect Yolo County birds.
“It’s a small thing, but all these small things eventually add up,” Brice says.
For more information about the Yolo County Audubon Society, go to https://yoloaudubon.org/. For information about joining the Putah Creek Christmas Bird Count, go to yoloaudubon.org/christmas-bird-count/.]]>