Signs of Spring
The transition from one season to the next stirs a variety of emotions in people, but the passage of winter into spring is unrivaled in this capacity. Many have written about spring as a period of rebirth and renewal. For me, the journey towards spring is best encapsulated by one word: anticipation.
One of the great joys in life is anticipation; the days leading up to a vacation, the moment before biting into a piece of blueberry pie, and for birders, the weeks preceding Spring Migration. For the non-birders out there, spring migration is the period when birds that have traveled south for the winter make their journey back north to breed. (The same phenomenon occurs in the southern hemisphere for their spring, although generally it happens on a smaller scale.) Because birds are such vivid parts of the landscape, their absence and subsequent reappearance is tangible even for those who don’t know the difference between an eagle and a hummingbird. This is why there are festivals celebrating the return of birds in the spring; the swallows of San Juan Capistrano is a particularly well-known example, but now there are festivals all over the world celebrating spring migration: Ohio’s The biggest week in American birding; Ontario’s Festival of Birds; Alaska’s Copper River Delta Shorebird Festival; and Croatia's Stork Festival are just a few examples.
Migrating birds are not the only harbingers of spring, however, and I’m going to cover a few other examples from this past week here on Quadra Island. Before I jump into those, I want to acknowledge the incredible celestial event that transpired on Wednesday this week; the "worm" (or sap) supermoon that rose a few hours after the vernal equinox. The last time we had a supermoon on the spring equinox was 1905, and the next one will be in 2144. So I hope you got to see this one; if not, enjoy some of the photos taken from Rebecca Spit Provincial Park as the moon rose over the Coast Range mountains right around sunset.
The first two “signs of spring” examples I’ll present may come as a surprise to some, but they represent a wide-spread phenomenon: amphibians on the march in the cold. With ice still clinging to ponds, and patches of snow lurking in the shadows, the longer days have triggered the alarm clocks for many species of ectotherms (“cold-blooded” animals) to emerge from their winter refugia. So while most feathered spring migrants are still drinking cocktails in tropical or semi-tropical climes, and many furry inhabitants are still snoozing in their dens, lots of amphibians are out on the prowl. And they are on the hunt for love.
This past week we had a rain event followed by some warmer days which brought the rough-skinned newts (Taricha granulosa) onto the island’s trails and roads. These amphibians breed in ponds and slow-moving sections of streams, and they travel from their terrestrial winter burrows to water bodies to find other newts. If multiple males encounter a female at the same time, they form writhing masses of limbs and tails fondly referred to as “newt balls,” in which one male attempts to wrestle the female (generally in the center of the newt ball) away from the competition. The successful male will then deposit a spermatophore (sperm packet) on the substrate which the female picks up with her cloaca, and uses to fertilize her eggs. She deposits fertilized eggs onto submerged vegetation within a few weeks, and then leaves them to develop on their own. But the eggs, like the adults, are not defenseless; rough-skinned newts (and their eggs) contain a potent neurotoxin (tetrodotoxin—perhaps better known from the Fugu pufferfish) that protects them from most predators. It does not protect them from cars or hikers’ shoes, however, so if you’re active in areas where these slow-moving amphibians are found, keep an eye out for them.
The next early-spring riser is the Pacific tree frog, or Pacific chorus frog (Pseudacris regilla). These little frogs are incredibly hardy; I’ve heard individuals vocalizing from patches of vegetation or rocks when the temps were just above freezing. I should note that these “cree-eek” croaks (known as the “dry land call”) came out at half speed, and without much enthusiasm. Now that daytime temps are well above freezing, these frogs have ratcheted up their activity to a fever-pitch. They congregate around just about any body of water and males use their “advertisement calls” to attract females. They advertise their good genes with “rib-bit” calls, performed at a much faster rate than the “cree-eek” calls, and with much more enthusiasm, even if the temps drop down close to freezing. Most of this calling happens at night, but in these first few warm days of spring, the males have kept with their singing all day long. Soon the jelly-like egg masses will start appearing in the ponds and drainage ditches, and the next generation of tree frogs will be on the way.
Our final telltale sign of spring is an auditory signal, like the frog calls, and it takes us back to the birds: I’m talking about the reverberating drumming of the woodpecker. The spring hammering is distinct from the pecking used to find food, which is usually a relatively slow, methodical tapping as part of the excavation process. Here's video of a male pileated woodpecker excavating a dead tree in search of food at Rebecca Spit Provincial Park. (For a bit of fun, slow the video down to half speed and watch the woodpecker's tongue dart in and out.)
The spring drumming, by contrast, is a male woodpecker’s proclamation of vigor, and is used to stake out a territory and attract a mate. The louder and more reverberant the sound, the better. This explains why people sometimes find themselves on the inside of a woodpecker acoustic amplifier at 5am; metal roofs and flashing, vinyl siding, and other home materials with good resonance properties are magnets for woodpeckers looking to make a statement. And they love to make that statement early in the morning when sounds travel far through the cool, calm air.
But woodpeckers aren’t picky; they’ll happily use a hollow tree, lamppost, or metal gate, which is what seems to be the medium of choice for northern flickers on one stretch of the island. Here’s a short video I captured of a male drumming on a metal gate.
About 10 minutes later, and a half mile down the road, I came across another male flicker using a very similar metal gate as his amplifier. Apparently the word is out on Sutil Road; metal gates are great for drumming. And they won’t lead to angry, half-awake humans throwing rocks at you (or worse).
So with the season of anticipation fully upon us, I'll be watching for returning birds, emerging bulbs and amphibians, new growth on trees and bushes, and a host of other signs that spring is really here.
Next week: TBA. *Note—I said this week would feature sea lions running the narrows, but the onset of spring and associated events took precedence. We’ll get to the sea lions at some point!
3/22/2019 04:49:15 pm
Excellent, excellent, Loren, have you ever considered writing a novel? Perhaps science fiction.
3/25/2019 07:47:06 am
Leave a Reply.
About the author:
Loren grew up in the wilds of Boston, Massachusetts, and honed his natural history skills in the urban backyard. He attended Cornell University for his undergraduate degree in Natural Resources, and received his PhD in Ecology from the University of California, Santa Barbara. He has traveled extensively, and in the past few years has developed an affliction for wildlife photography.