Didja know real life is ridiculously complicated? Even simple things involve a lot, if your observation runs close enough – one classic example of baking a pie from scratch requiring the creation of a universe. Causes are often multifactorial, because how could they not be? The pie example runs through the ingredients, the cultivation of apples and wheat and cows to make butter etc., but that pie also needs a human to put it together, who must be educated from societies that had to evolve all the way up from monkey grunting, besides the hundreds of millions of years since we diverged from our last common ancestor with apples, and the billions of years of natural selection running to the two minutes after the Hadean magma cooled.
So I say that if you’re genuinely trying to arrive at the truth of a given thing, you need to wrack your brain for all the considerations, contingencies, and possibilities. If you wants tha Real Science, you gots ta be willing to come up with a lot more than a single hypothesis. Yes, to test, you have to narrow things down to the ideas you’re going to test, but to make that test as rigorous as possible, you should really try to think of every possible factor that could confound the results. Stretch that brain. Presumably that’s why you went into science, right? To feel smart?
But no. It’s easier to feel smart if you blithely whistle past all the ways you could be wrong, like evopsych assholes and scientific racists (how much overlap those fields possess). One hypothesis. A few cheesy tests. Maybe squint and look at the data sideways, and by jove, you’ve cracked it! Now go get as many women pregnant as possible, to share your genetic genius with the world.
Over here in the real world, you could be like me, and know just enough to be sure you’ll never fully understand anything. Don’t throw your hands up and veg out watching George Michaels videos on yewchoob until you die. Stay wondering. Be frustrated forever by the fact real science hurts, and take your cold solace in the awareness at least you aren’t an evopsych fucko, or qanon, or moon landing truther, etc etc.
Here I come to the actual point of the article. Does anyone know why crow populations are skyrocketing in the Pacific Northwest? I could be wrong about this, but to my slightly-less-than-casual observation, they may have doubled or tripled in population within the last few years. This was well after a documented boom they had back in the late twentieth century.
A possible point of failure in this question: observational bias. Most of my travels in a given week range from Auburn to Federal Way and back – up and down the west side of one little valley. Maybe there are more crows here than elsewhere. Maybe I had poorer observation of their numbers in previous years because I wasn’t paying as close of attention. Maybe my mind is exaggerating, and they always gathered by the hundreds on the edge of the mall, sunning themselves in the morning light, in preparation for the daily hustle. Maybe if I’d been driven down the west end of Main Street before, at the right time of day, I would have already seen them dotting the little lawns and parking lots and rooftops and trees, in groups ranging from dozens to hundreds, block after block. Maybe they would always gather in megaflocks in the south of Auburn somewhere, making a cacophony that can be heard a mile away.
Sounded like I was trying to convince myself my observations were accurate toward the end of that paragraph, but I absolutely do recognize this perception could be flawed. It literally could be a matter that I was never in the right place or time of day or time of year to see these crow convocations before. In which case, there’s no phenomenon to wonder about. But assuming there is a phenomenon, what’s causing it..?
Here’s where the range of possibilities starts to hurt the brain. If I was a shit scientist instead of a vexed layperson, I would just cook up one hypothesis and a single test to run for it, then congratulate myself in print and get quoted in popular science magazines. Instead, I sit here realizing how complex this can be – maybe even unknowable. Some things I’ve considered:
Food explosion. I learned from Abe Oceanoxia that invasive European earthworms have taken over the USA in huge numbers, and crows happily eat a lot of worms, whatever their proclivity for french fries. Maybe earthworms are having a population explosion for reasons I can’t even begin to guess at. Or maybe they’re just more available, because long years of drought seem to have ended here, and rain drives them to the surfaces of lawns and sidewalks. Any given rainy day, you’ll see robins and crows both going for the wriggly pink smorgasbord, crows most of all.
Or maybe there’s another food altogether that has increased. As covid and the ascent of global fascism have fostered a sense of doom in the younger generations, increasing deaths from despair, it has certainly increased the amount of litter. Is the food explosion mostly human trash?
Predator decline. I’ve heard that owls are the most prolific predators of crows. I imagine cats and dogs take their share as well. Well, we’ve no shortage of cats and dogs, but maybe the species of owl that eats crows has taken a population hit – or altered their behavior based on availability of a different prey animal or animals.
Or maybe a competing predator of the food they eat has experienced a decline, like worms becoming overpopulated due to a mole plague.
Natural selection. Maybe a disease that had been killing crows had winnowed the population to those crows with a resistance, and those crows in turn had a big population boom? Maybe crows had only bred at certain times of year to avoid competing with themselves but that was an obsolete limitation and year-long breeding finally won out majority expression in the population? Maybe something crows eat had an evolutionary breakthrough and exploded.
Cultural selection. Maybe crows figured out a cool trick they hadn’t done before. I was once impressed by watching a crow use a tool, but since then have seen it again several times. What’s interesting is the tool is the same – a short straight stick, just a few inches. Was the technique of crafting this tool communicated, or were they all learning to go for the same source for the tool, or have I just seen one crow who packs its tool everywhere it goes, and gets around?
I haven’t seen this so often that it could make that big a population difference, but maybe there is some other behavioral trait they’ve increased. Maybe they mob raptors and ravens so often now that they are being preyed upon less often, or are competing less for food. Maybe they’ve increased the frequency of the food call. There’s a tension in crow instincts between the desire to have food all to oneself and the desire to call a bunch of crows in to share. If they’re all doing the food call more often, they’re eating food before any competing species can get to it.
My husband saw a yewchoob vid where some weirdos left a mound of peanut butter in the woods and crows ate almost all of it, beating out bears and coyotes and raccoons and more, strictly because of this instinct to call in your friends. Well, that and having less hesitation about strange food sources. The coyote missed out because he was too scared of the blob to eat it. Maybe the hesitation recently reduced even more.
Commensalism. Human population in the region has also exploded. The town I live in has three times as many people as it did when I first moved here as a child. More people, more lawns with worms, more fast food places and restaurants producing food waste, more rats and mice and pigeons and starlings to eat. I’ve seen them eat pigeons and starlings before. Hell, an increase in predatory behavior could drive population, or even cause an evolutionary split between crows with different feeding habits.
Niche partitioning. Maybe that last one is it. Maybe there’s been an invisible split along behavioral lines in food gleaning, which is the beginning of a speciation event that may or may not ever reach completion before it collapses back in on itself due to climate change or other human issues.
Some or all of the above. The cause is multifactorial after all.
None of the above. Phenomenon isn’t real. I’m tripping and all this thought is for nothing.
Hell, all this thought assuredly is for nothing because I will never know the answer, whether it’s knowable or not. And yet the thoughts still happen. At least it shows I’m smarter than an evopsych dick. That’s nice.
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