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Climate Change Is Driving Changes In Wildflowers At Mount Rainier National Park


Climate change is driving changes in the blooming of wildflowers at Mount Rainier National Park/Elli Theobald

Riots of blooming wildflowers are one of the joys of visiting national parks, but climate change is tinkering with the schedule of some of those flowers. At Mount Rainier National Park in Washington, for instance, all wildflower species are blooming earlier than in the past, roughly half have extended their season, and a little less than half shortened theirs, according to research conducted by University of Washington personnel.

A trio of ecologists from the university stumbled upon this alteration while collecting data on the subalpine wildflowers that bloom each summer on the slopes of Mount Rainier. As they report in a paper published online last month in the journal Ecology, an unseasonably warm, dry summer in 2015 caused reassembly among these subalpine wildflower communities.

The conditions in 2015 gave the team — consisting of doctoral student Elli Theobald, doctoral student Ian Breckheimer and biology professor Janneke Hille Ris Lambers — a preview of what subalpine communities may look like by the end of this century. By then, significant climate change is expected to permanently alter environmental cues that wildflowers rely upon and make community reassembly a more common phenomenon — with unknown consequences for species interactions in those communities.

"2015 was such an outlier that it gave us a glimpse of what this environment on Mount Rainier might be like toward the end of this century," said Theobald, who is co-lead-author on the paper with Breckheimer. "Conditions were so warm that they affected the flowering time and flowering duration of species, forming communities in 2015 that simply did not exist in the other years of our study."

Their study is one of few to demonstrate evidence for community-level reassembly among multiple species.

"These reassembled communities could potentially change the interactions among wildflowers and other species in this subalpine setting," said Theobald.

For six summers from 2010 to 2015, Theobald tracked environmental conditions and plant behavior for 48 species at 70 field plots, each one square meter, along the southern slope of Mount Rainier. The plots ranged from 1,490 to 1,901 meters in elevation. Within each plot, Theobald used sensors to record temperature, snowmelt, and soil moisture content.

"At these elevations on Mount Rainier, snow is the major driver of plant behavior, because the annual cycle of flowering and reproducing cannot begin until the snow melts," said Hille Ris Lambers. "If there is snow on the ground, plants cannot photosynthesize, and if they cannot photosynthesize, they cannot grow."

All wildflower species at the park are blooming earlier, and a little more than half are staying in bloom longer/Gary Vogt file

When the sensors reported that snow had melted at each plot, Theobald collected data on when plants would emerge, flower, and begin to produce fruit. These included species familiar to hikers such as avalanche lily, magenta paintbrush, mountain blueberry, wild huckleberry and wild lupines.

Most of these plants are perennials, which retreat underground each winter. But when snow melts, they typically have a two- to four-month window — depending on elevation and position — to grow, flower and produce fruit and seeds for the next generation before snow returns.

In 2015, conditions were so warm that, on average, snow began to melt at the study plots 58 days earlier than in 2010-2014. The team recorded major shifts in the bloom times of wildflower species. All of the species — 100 percent — flowered earlier in 2015 and 54 percent of species also lengthened their flower duration that year, some by as many as 15 days. The remaining species showed shorter flower duration, in one case by nearly 19 days, possibly due to accelerated soil drying, altered pollinator activity or other factors.

Since species shifted in different ways, conditions in 2015 produced new patterns of reassembled wildflower communities, with unknown ecological consequences.

"These are species that have always coexisted at these subalpine sites," said Theobald. "But in 2015, we saw species flowering at the same time that normally flowered weeks apart."

The team saw the most dramatic signs of reassembly among plants that normally flowered early in the summer. These plants tended to grow at sites experiencing less snowfall — such as plots at lower elevations, or along ridges and slopes instead of coves and valleys, where snow tends to accumulate. In addition, the plants that tended to lengthen flowering duration did so if they experienced a greater number of warm, photosynthetically "productive" days in 2015.

Reassembly on the scale that the researchers saw in 2015 — and that Mount Rainier may see every year by the end of this century — may change interactions among species. For example, plants could compete for access to pollinators, which at Mount Rainier include bumblebees, flies and hummingbirds.

"We simply don't yet have enough information to know who the 'winners' and 'losers' of reassembly will be, or even what 'winning' or 'losing' in such a scenario would look like," said Theobald.

To predict that, scientists must observe and test how ecological reassembly affects reproduction for all species in these regions — from flowers and pollinators, to even the bears that feed on subalpine berries. These effects will also impact the people who visit these sites and try to preserve them.

"All of these interactions among species — and how those interactions will shift due to climate change — will affect how we manage these sites," said Hille Ris Lambers. "After all, Mount Rainier is a national park that is here for all of us, as well as the species that call it home."

Glacier lilies in bloom at Mount Rainier/Rebecca Latson file


I'm sure Zinke and drumpf will soon label these studies as "Baloney."  Is the goal of these creeps the complete destruction of the hard won environmental progress of the last 40 years?  Whether it's elephants in Africa or oil wells beside Dinosaur or Theadore Roosevelt, or simply pumping more dollars into pockets of the most wealthy people in our nation, there seems to be nothing our current administration will not stoop to.  


People who care absolutely MUST step up and join the fight to bring sanity back to America. 

This is a very interesting article.  When I visited Mount Rainier July 5th and then again July 7-12, I couldn't believe the amazing varieties of wildflowers blooming.  Among the species, there were a plethora of avalanche lilies and glacier lilies blooming up at Paradise. I tried to photograph as many as I could, but know I missed many species.

What is fascinating to me is how we seem to have decided that the most recent period of time is the "ideal" climate for some reason. I assume that because that is what we have all shaped our lives around and are the most comfortable with. This despite the fact we live in vastly different climates already. Those living closer to the equator likely think those living in the north are crazy and vice versa. I wonder if you told the people living 10,000 years ago what the climate would be like today, would they have viewed it as negatively as most view any change do today? Or would they have looked at the positive aspects of it? It would also be interesting to see how the population and technology of today adapts to the changes happening over the course of the next few hundred years. Will the population centers shift further north? Unfortunately I wont be around long enough to see it.

I am reminded of reading the writings of Seth Kantner, who was raised in a dirt hut in subsistence lifestyle in northern Alaska. Over the course of his life he has watched the changing latitude and the changing time of reappearance of the foliage around him. Living off the land remotely, he was very attuned to these changes, their effect on wildlife, and so on down his food chain.

Wild places, I'm not sure you "get" it.  Lots of things will go extinct because of this.  We are not discussing needing to shed a coat.

argalite, what I "get" is you have been so brainwashed that you can't even consider that some species will thrive, that there will be both good and bad and winners and losers. How many species thrived due to the end of the ice age? Was that a bad thing? Or is your goal to return to that period? If not why not? Tell me why you and so many others have decided that the climate we had at the time AL Gore released his movie was the perfect climate.

The nice thing about The Traveler is that a good thread never ends. Argalite, this is from George and Gracie, the family cats:

You asked today about this "thing" Al has with wind farms, and blamed us again for killing birds. We've killed none so far that Al knows of, but we sure have killed our share of rats. Did George tell you about the one he left under Al's desk? Ha! It took him two days before he smelled it, got out the flashlight, and dragged it out by its tail. Then there was the one George left in the bedroom, and Al almost stepped on it. I Gracie laughed so hard I fell over.

Now, about these wind farms, Argalite. They don't kill just "any" bird. They kill the big ones, the eagles and other raptors. George and I could not possibly kill one of those.

It's about perspective, Argalite, like the word extinction, which you freely band about like a rubber stamp. "Lots of things will go extinct," you say above. But we have news for you. It won't be rats. But yes, wind farms are indeed a major threat to lowered populations of eagles, hawks, owls, and bats. When the U.S. Fish and Wildlife Service confidently reports that there are 143,000 eagles in the United States, whom do they think they are kidding? There are that many rats in Al's backyard! True, we're including the sewer system, but there have to be at least five million rats in Seattle, and no, we're not including the City Council. Even if we cats were as efficient as you say, we could not possibly kill all of the pigeons, starlings, and sparrows inside the city limits. But yes, a wind farm can knock out every breeding pair of eagles within miles around.

It's not global warming that threatens the human race. It's rather the human race itself. There are just too many of you, doing too many wrong things, of which owning cats is not among them. Sure, we kill our share of birds, but at least we don't kill one another. You kill everything that moves, and then blame it on something else. Just using cars you kill one million animals a day. Why are you blaming cats?

George and I will tell you why. Because people these days are lazy thinkers. It's all about winning an argument, not using common sense. If the world weren't getting warmer, for example, what exactly would it be doing? Getting colder? Staying the same? Since when has the Earth ever been "predictable?" The next thing you know, that big volcano NOVA was reporting on the other night will blow again--and plunge the temperature of the Earth by several degrees. Or it won't blow--and the Earth will continue warming. That is the "risk" you humans take. We cats take the risk that something will get us, too, but at least we don't have to fly through wind farms.

Stop moaning and take a nap. We sleep 17 hours a day. Perhaps if you slept a bit more--and turned off CNN--the world would seem a better place.

George and Gracie, fun post.  I think you cats made a good point, population is a serious issue, not only do all of us contribute to the complexity of all these issues, cats included, but the development, resources, etc. needed to sustain the growth is probably an impossibility. One thing is for sure, things are going to change. A fan of CNN, many other interesting news souces as well, I humbly suggest you nice cats might want to watch something besides "FOX News" after your naps. 

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