Saturday, October 17, 2020

Iowa: A lovely place to spend the winter

 

Song Sparrow

Most people think of bird migration in terms of "flying south for the winter". All those birds whose company we enjoyed throughout their summer nesting season fatten up and begin their long, arduous journeys to warmer climes in the southern US, or Central and South America to while away the winter months.

But for some birds, those warmer climes are...here, in Iowa and the midwest. They spent their breeding season in the far north: the Canadian boreal forest and other near-arctic regions. Many of them will simply pass through our area as they head further south with the other birds, but a few hardy little birds will stick it out here, through Iowa's short, windswept days and long, freezing nights. 

Dark-eyed Junco

Meet our winter sparrows! All can be found along the Greenway trail in winter, and you can also get to know many at closer range if you have backyard feeders (Project Feederwatch is a great citizen science program that involves winter birds). All the little brown birds can be daunting to tell apart at first, but with close observation of key features it gets a little easier!

American Tree Sparrow
A perennial winter favorite--and one of the easiest sparrows to identify--is the charming Dark-eyed Junco (Junco hyemalis). There are a few geographical variations, but around here they generally have a solid gray head and body with a white belly. If you just catch them taking flight from a distance, you can see the white feathers on the outer edges of their tails.

The American Tree Sparrow (Spizelloides arborea), has a bicolored bill and dark spot on its unstreaked chest. It has a rusty cap with a matching stripe through its eye.

Fox Sparrow
Fox Sparrows (Passerella iliaca) closely resemble the more common Song Sparrow, with heavily streaked breasts. Though their color is variable, the Fox Sparrow is generally more foxy reddish brown, and the streaks on its breast are heavier, with spots shaped like chevrons. Its face also seems to me to have less, and less well-defined, white markings than the Song Sparrow.

The beautiful black-and-white striped cap of the White-crowned Sparrow (Zonotrichia leucophrys) is very distinctive, atop a fairly plain and uniformly gray face and throat. The White-throated Sparrow (Zonotrichia albicollis) has a similarly streaked cap, but also sports a clean white throat as well as yellow mark in front of its eyes. (To complicate matters, there is also a tan-striped form where the white crown streaks are replaced with tan.)

White-crowned Sparrow

White-throated Sparrow
 

In addition to these snowbirds, there are several other sparrows that spend the entire year with us. Prominent on the Greenway are the Song Sparrows (Melospiza melodia), with heavily-streaked breasts with a central dark spot. These are one of the most common sparrows you'll probably encounter on the trail.

Swamp Sparrow
Much less common but still reported year-round are Field Sparrows (Spizella pusilla), featuring a pink bill and white eyering (their facial features look soft to me, with a blushy cheek spot), and the Swamp Sparrow (Melospiza georgiana), with a more skulking habit, gray face with reddish cap, and a white throat. 

And last but not least are our two non-native sparrows. House Sparrows (Passer domesticus) should be familiar to anyone who pays attention to birds! They hang around in noisy flocks, the plumage of the winter males--black bibs, gray caps with white cheeks, and reddish-brown napes--more subdued than their summertime feathers. The females are very plain brown, with a light brown stripe above the eye.

House Sparrow (male)
House Sparrow (female)

Eurasian Tree Sparrows (Passer montanus), look similar to male House Sparrows, but they have a handsome brown cap and a distinctive black spot on their white cheeks (males and females look the same). They are less common around here than the ubiquitous House Sparrow, but there is a small flock resident near the woods on the north end of the Greenway. 

Eurasian Tree Sparrow





Friday, October 2, 2020

The Ethical Grasshopper

 The scattered grasshoppers springing away from each footstep as winter approaches bring to mind the old fable about the ant and the grasshopper. 

At base, 'tis a tale of woe (or a hard moral tale, for the formican fellow travelers) about an improvident orthopteran who, having spent the summer singing and frolicking, faced the ominous winter's advance empty-handed (empty-tarsused?). Beseeching the industrious ants for a portion of the stores they put by for winter, the grasshopper is rebuffed and left to starve in the cold. The ants, presumably, while away the winter congratulating themselves on their hard work and foresight.

Given the millennia the fable has enjoyed the attention of artists, storytellers, and politicians, the simple story has evolved a variety of morals. At base, it is about preparing for the vagaries of life and being mindful that times of plenty are inevitably followed by times of scarcity. One must prepare for bad times during the good. One must balance work and play, and devote time to each accordingly. Those who don't do so cannot expect to live off the fruits of others' labor.

Alternatively, the grasshopper has taken on the role as a symbol of the arts in some tellings: one whose work is not productive in a traditional sense but no less worthy of a place in our society. In this case, the stingy ants, with their cramped and cruel lives obsessed only with accumulating resources, become the villains. The grasshopper living joyously and for the moment, is not troubled with thoughts of scarcity or the long, dark nights of winter. The pleasure of his song is enjoyed by all, but not valued as it should be. The starving artist, undervalued and underappreciated on the margins of society.

A middle ground declares the ants in the right for their industriousness, but wrong in their uncharitable treatment of the grasshopper. Although L'Estrange seems to come down on Team Ant in his translation, the final comment embraces a merciful outlook:

[W]e have our failings, every mother's child of us, and the improvidence of my neighbour must not make me inhumane. The ant did well to reprove the grasshopper for her slothfulness; but she did ill then to refuse her a charity in her distress.

 All this is a rambling preamble for me to say, I think the grasshopper was done dirty in the fable.

You can't hold a grasshopper to an ant's standards. They are different organisms, with different niches and different behaviors to exploit those niches. The grasshopper's life is meant to end with the coming of winter. We don't blame the summer flowers for withering and passing away with the winter winds. That is the end of their life cycle, as it is for the grasshopper.

Grasshoppers generally live independently*, not in a cooperative eusocial colony where each individual is subsumed within the whole. Even if the ants had agreed to share their food, could the grasshopper survive? Does the grasshopper have the physical ability to excavate a burrow or other cavity to protect it from the winter winds and snow? Would it need to rely on the ants not only for sustenance, but shelter as well? Would it even want to suffer through those long months, unable to hop and bask in the warm sun, unable to snap their wings and munch on petals?

And what of the ant's diet? Grasshoppers are herbivores**, eating leaves and flowers though perhaps not terribly choosy about the source. Would a grasshopper be interested in what the ant has stowed away in its larder? Depending on the species, it could be fungus or honeydew, or other insects and their eggs.

I suppose the moral of the story, then, is that we must not expect different organisms to conform to the expectations of others; each has its role to play and its place in the world.

*With some exceptions: swarms of locusts, in biblical lore and throughout history, are grasshoppers whose swarming behavior is triggered by climactic conditions, when they enter a "gregarious phase". 

**Again, with some exceptions: a few species may eat flesh or feces, and even those who are regularly herbivorous are not above munching on the occasional insect carcass they stumble upon, for a boost of protein.