As spring works its way northward, at about sixteen miles a day, we start to take note of the changes around us: birds absent since last fall return, buds swell on trees, the first flowers push through the thawing ground and begin to open. Many nature enthusiasts keep lists of these seasonal events, recording the arrival of the first robin, the opening of the first pussy willows, the songs of the first frogs. This study of seasonal events, whether formally or informally done, is known as phenology.
The word phenology comes to us from the Greek word phainomai, which roughly translates as “to appear” or “to come into view.”
Now, some of you might think that keeping track of when the first dandelion blooms, or when the first swallows cut across the sky would become pretty dull after a while, but just the opposite is true. For us dyed-in-the-wool naturalists, taking note of these harbingers of the seasons is like greeting old friends at the bus station. Each return after a cold grey winter brings a smile to our lips. Our friends have come back; the next season is on the way.
2010 marks the tenth year that I have kept phonological records here in Newcomb. It isn’t long enough to note significant changes in many of the seasons’ firsts, but for those who’ve kept records for many more years, patterns are becoming clear. Change is in the wind. Up in the Arctic Circle, areas of permafrost are no longer so “perma” – seasons of melt are arriving sooner and lasting longer. In more tropical climes, changes have been less significant – after all, they don’t have the seasons that those of us closer to the poles experience, so changes are difficult to note.
In general, scientists have determined that spring and summer are both arriving about two and a half days earlier every decade. Some birds are arriving at their nesting grounds up to three weeks sooner than they did historically. This can lead to catastrophic population problems. You see, when nature is in balance, migrating animals show up at their breeding grounds in perfect time for the food to be there for lactating mothers (who need more food in order to produce milk for their young), and hungry newborns (think of how many insects a robin, for example, must find to feed its nestlings). When these animals arrive too soon, due to warmer temperatures which have cued them to migrate, the food they need may not be available. The end result: offspring die from starvation.
On the other hand, some animals migrate based on daylength (photoperiod). If warming temperatures are causing plants to bloom (and fruit) earlier, and the animals who depend on them for food arrive at the traditional time, there may not be food around when the young arrive – the food already came and went. Again, the offspring die. Populations start to fall.
What we are seeing is synchronization thrown out of whack.
But we don’t live in the Arctic Circle. These things don’t affect us here in New York. The planet has gone through temperature cycles before – it’s nothing new. And really, what difference does a couple degrees make anyway?
I’ve heard these arguments before, and in some cases I can see the logic. Yes, Earth has had cyclical climate changes before. Some years are naturally colder, and others are naturally warmer. And a couple degrees may not seem like a whole lot. But what we have to keep in mind is that the changes we are seeing today are happening a lot more quickly than they did in the past. Plants and animals are having to deal with changes on a time scale never before encountered. In the past, they had time to move and adapt. Not so now. And it is phenological records, kept by amateurs and professionals alike, that have brought these changes to light.
Yesterday morning I went out to fill my birdfeeders before going to work, and discovered the tulips and daffodils had already broken through the ground along the side of the house. It’s early March! These plants should still be snuggled beneath the ground, storing up energy for April, the traditional time for the sun to melt the snow next to the house and thaw the ground. According to my records, I don’t usually see daffodils in bloom until mid-April. It should be interesting to see when they flower this year.
Change is coming, and you, too, can witness it. All you need to do is start keeping track of the year’s firsts. A notebook and a pencil will do, or you can go high-tech and keep track on a computer spreadsheet. Starting this month, take note of what is happening around your house. Did you see a bluebird? Have the maple tappers put out their buckets yet? Are the deer shedding? Soon these occurrences will become dear friends, and like the rest of us phenologists, you will look forward to greeting them year after year.