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For a few weeks in February, it sure felt like spring was very near in Paradelle – or maybe it had arrived early – even if the calendar and Earth’s tilt said otherwise. I saw crocuses and daffodils up and blooming. Tree buds seemed to be starting their bud burst.
Then the thermometer reversed itself and we had our biggest snow of the winter.
The news reported that the cherry blossoms in the nation’s capital are threatened, and the ones in New Jersey, which generally peak in early April, might also be affected. [Not So Trivial Fact: New Jersey has more cherry trees than Washington D.C. – the largest cherry blossom collection in the United States. But the Branch Brook Park cherry blossom webcam in Newark just shows bare trees and snow as I write this.]
I have written before about the study of cyclic, seasonal natural phenomena which is called phenology. The National Phenology Network tracks “Nature’s Calendar” via phenological events. But can we actually predict the seasons with any accuracy?
These nature observations include the ones we all have been observing lately, such as trees and flowers, but also ones that you may not be able to observe or just don’t pay attention to. Those signs of seasonal change include male ungulates, such as elk or deer, growing antlers at the beginning of the rut and breeding season each year, mammals that hibernate seasonally to get through the winter, and bird migration during the year.
Other than the false Groundhog Day forced observations, phenological events can be incredibly sensitive to climate change. That change can be year-to-year, but the timing of many of these events is changing globally – and not always in the same direction and magnitude.
According to a Public Library of Science (PLOS) blog, “From 1982 to 2012, spring budburst (when the leaves first appear) has advanced by a bit over 10 days, while the onset of autumn in the northeast US has pushed back about 4.5 days. No trends were found for other regions. This lengthening of the growing season has profound implications for the ecology of these forests and potentially their ecological evolution. A longer growing season could translate to high carbon storage for increased growth, but higher rates of decomposition and changes in moisture availability. However, these changes in phenology are primarily driven by increasing temperatures. In a warmer world, some species may simply not be able to survive where they are now, creating a dramatic change in the species composition. And this is without considering changes in precipitation.”
The National Phenology Network’s project called Nature’s Notebook collects data from more than 15,000 naturalists across the nation who, using standardized methods, provide information about plant and animal phenology.
Project BudBurst is another citizen science focused project using observations of phenological events and phases through crowd-sourcing. Project like this give you the opportunity to make your observations of nature more conscious, and to contribute to the knowledge base.
This post first appeared, in slightly different form, on my Endangered New Jersey blog
Punxsutawney Phil the groundhog predicted another 6 weeks of winter, but on that day I saw a lone dandelion already blooming at the neighborhood park. Maybe it was being bold, or being stupid, to bloom so early. It was covered by snow the following week. But according to estimates by the National Phenology Network, spring has already arrived in much of the Southwest and Southeast. It was about 20 days early for the Southeast. They track Extended Spring Indices which are models that scientists have developed to predict the “start of spring” at a particular location.
This weekend in Paradelle, we are enjoying temperatures in the 50s and 60s after a windy week in the 20s and 30s. Such is this time of late winter and early spring.
I have written a few times about phenology which is the study of cyclic and seasonal natural phenomena, especially in relation to climate and plant and animal life.
They use historical observations of the timing of first leaf and first bloom of certain plants (for example, cloned lilacs and honeysuckles) and daily observations from weather stations.
Many deciduous plants in temperate systems put on their leaves as temperatures warm in late winter and early spring. Using the Extended Spring Index models, scientists can look at how much the start of spring has varied from one year to the next at a particular location, and whether recent years are dramatically different from the past or not. The models can also be used to forecast when selected plants might bloom or put on leaves in future years.
I have been keeping my own bloom records for my home turf for about 20 years. Though my property is certainly its own “micro-climate” with variations due to shade, soil etc., I have seen earlier springs over the years for certain plants that are my own little “control” group.
The USA National Phenology Network developed Nature’s Notebook, a project focused on collecting standardized ground observations of phenology by researchers, students and volunteers like me.
I think their mission should be everyone’s mission, even if you don’t get as official as doing phenology: Gain a better understanding through considered observation of the plant and animals that surround you and how they relate to your environment and broader environmental change.
Spring is officially still a month away for those of us in the Northern Hemisphere, but that doesn’t mean that you aren’t already observing signs of it in your little corner of the world.
I was looking at this very heavy textbook on phenology that I can’t imagine any of you opening up to read. I’m not going to get to read it through either, but I find the subject fascinating and there is plenty of information online to keep me busy.
It always makes me sad that we are not the observers of nature that people were in earlier centuries. People paid much closer attention to the world around them and how the plants were changing with the seasons and what phase the Moon was in what the animals and insects were up to. And a long time before we had a scientific name for it, people recorded signs of the seasonal changes.
Today we call this phenology – the study of seasonal change as reflected in plant and animal life. (Not to be confused with the phrenology – a definitely fringe study from the Victorian era when doctors believed they could tell everything about a person from mapping out the bumps and oddities of the human skull.)
Phenology is the study of plant and animal life cycle events, which are triggered by environmental changes, especially temperature.
You would note the first openings of leaf and flower buds, insect hatchings (fly fisherman do some of this) and the return or departure of birds and insects.
I think that this has become a bit more popular the past few decades as the they might be seen as indicators of the impact of local and global changes in weather and climate on the earth’s biosphere.
The father of modern phenology is Englishman Robert Marsham who began recording signs from nature in 1736 and continued for 62 years. The word is derived from the Greek phainō, “to show, to bring to light, make to appear” and logos for “the study of.”
I do my own amateur phenology because I am a gardener and because I enjoy being out in nature and keep my own little field guides and calendars of my little local biosphere. I record the emergence of leaves and flowers, the first flight of butterflies and the first appearance of certain migratory birds.
Spring is a time full of these events. I also record when I start my vegetable seeds, set the plants out and harvest the first crop. Of course, those dates are somewhat in my control and not phenology. But I start those seeds and set out those plants based on my observations from past years of frosts and the appearances of other plants and flowers in my area.
I read that viticultural records of grape harvests in Europe have been used to reconstruct a record of summer growing season temperatures going back more than 500 years.
Some of what I learned growing up might border on folk wisdom, but seem to hold true. Dandelions in full bloom means it is time to plant potatoes. My father told me we could plant peas on St. Patrick’s Day if the soil wasn’t muddy, but I got burned on that a few times. Safer to wait for the full flowering of forsythia to put the peas into the ground.
Frost dates are the usual way to go on planting, but those dates don’t change very often in books and guideseven though they vary quite a bit in my little local records.
If you have the pretty blue wild chicory blooms nearby in summer, it is time for squash vine borers who just love to attack unprotected squash and pumpkins.
Insects are often used as weather predictors. You probably have heard some version of observing insects flying lower to the ground before a storm, or that insects can sense the onset of very wet weather. They will be observed in monsoon and rainy areas invading buildings for shelter before a storm. Some ants will pile up dirt around the entrance to their underground homes to keep out water.
Phenology has gone from being a fringe science to a real way of understanding climate change. It also a citizen scientist activity and there are lots of websites that allow you to record your garden, bird and insect observations into a database which gives scientists a huge amount of data to work with. Project Bud Burst in the U.S. and Nature’s Calendar in the U.K> are two examples. In the US, you can also participate in the reporting program conducted by the National Phenology Network. There is the University of Berlin’s International Phenological Gardens that collate observations from 89 gardens in 19 European countries. And Earthwatch programs in Australia and other countries will increase the database.
A term that I picked up in my reading is “season creep.” People are observing birds laying their eggs earlier and buds appearing on some trees much earlier. Northern hardwood forests have been leafing out sooner and retaining their green canopies longer and the agricultural growing season has also expanded by 10–20 days over the last few decades.
Does this prove climate change or global warming. Probably not. The Earth goes through long cycles and we are probably on a warming trend now. The many droughts and violent storms are also indicators. Of course, the climate change argument really centers on whether or not it is man’s activities that have caused this change or is it just nature. I side with the blame people side on this because the changes seem to be progressing unnaturally fast.
All that Big Science on temperature, moisture, and changing sea levels is important. But, I am really “thinking globally, acting locally” with my calendar and journal and more interested in getting people to reconnect to plants and animals. My posts on the Full Moons and even those on weather lore are really just part of that idea of observing the place where you live.
It has been 17 years and now a new cohort of cicadas are ready to emerge again in Paradelle.
Why? We’re not quite sure – which is one reason I am intrigued by them.
I am reading now a book on phenology, which is the study of how we can observe seasonal change in plants and animals. I am also reading a book on the daily rituals of creative people. The two books are mixing in my brain in interesting ways.
Cicadas are chirping around in my head this month too, as are the migrating red knot birds that will be coming to New Jersey to feed on the horseshoe crab eggs as those ancient creatures perform their annual ritual that is connected to the moon and tides.
I like reading and thinking about these things that scientists haven’t quite figured out. I like wondering how those migrating birds or homing pigeons find their way. Researchers say that it seems to have something to do with magnetic fields and maybe the sun or moon. But really, we’re not completely sure. And I like that there is still that mystery to it.
With cicadas, one theory is that the cycles were a mechanism to deal with a cooling climate during the ice ages that occurred over the past several million years. Another posits the cycles are a way of avoiding predators.
Most of you probably can recognize the male cicada’s choppy, chirp, summer mating call. I was talking to a friend about this and she said, “How can it be a 17 year cycle when I hear and see them every year?”
Good question. These particular “periodical” cicadas are different from the annual cicadas that we hear every summer. Periodical cicadas might have been called “17-year locusts” or “13-year locusts” in your neighborhood. “Locust” always suggest some plague of insects, but cicadas are not true locusts (which are a type of grasshopper).
I am writing here about the species, Magicicada. You can spot the adults by their black bodies and bright red eyes and orange wing veins. They have a black “W” near the tips of the forewings.
In New Jersey, we commonly have the Macicada Septendecim which, like our mosquitoes, are the largest in size and have orange bands on the abdomen.
That rather ugly mating call, which some people say sounds like they are saying “pharaoh,” can get on your nerves, but is very much a sound of the start of summer to me since they appear mostly in May and June. Right now, soil temperatures are still in the mid-50s across New Jersey and Rutgers University reports that the cicadas are expected around the time we head to the Jersey Shore – late May. Soil down 8 inches warms slowly and cicadas won’t be fooled by a some 70 and 80 degrees days.
2013 is expected to be one of the largest broods recorded. That excites entomologists and probably repels most of the population. I don’t find cicadas lovely, but I do find these periodical ones to be fascinating. I am imagining them underground for 13 or 17 years waiting for some signal that it is time to emerge. We know that they won’t come out this year until the soil temperature about eight inches below the surface is a nice constant 64 degrees.
But why this year? Why wait 17 years? We are just not sure. There are exceptions. One swarm emerged in NJ four years ago ahead of this year’s due date. We don’t know why that happened either. Scientists didn’t get to study them because they were killed off by predators before researchers could study them. It just wasn’t their time.
After they emerge from that Rip van Winkle sleep, they go through a metamorphosis just a few hours later. They go from the flightless, slow-moving nymph stage into a large, flying insect.
They try to head for the sky before predators like dogs, cats, snakes, squirrels, deer, raccoons, mice, ants, and wasps get them. Once in the air, they still have to avoid birds.
They don’t need to worry too much about people, although some people do eat them. It is said that they have a taste that is sort of asparagus and nutty and best served when they molt and are still soft.
This post duplicates most of a post from another blog of mine called Endangered New Jersey – although periodical cicadas are not endangered they are a rather rare occurrence. If you want to be a citizen scientist, you can report cicada spottings at magicicada.org and your data will help map where and when the cicadas emerge this year.
Another interesting citizen scientist project comes from WNYC radio and the program Radiolab (which I wrote about earlier) who have created a place online to track cicada emergence in the northeast. If you are a DIY type, you might get into building the device they describe to predict their appearance in your backyard. See the WNYC Cicada Tracker page.