Laura Erickson's For the Birds

Thursday, February 23, 2023

Together and Apart

Our Birth Announcement Drawing: Baby and Wood Stork

One of my favorite poems is Robert Frost’s The Tuft of Flowers, especially the lines: 

‘Men work together,’ I told him from the heart.
‘Whether they work together or apart.’ 

We all love stories about families who enjoy doing the same things together, but really, how often are all the members of any family of five, or even just four or three, equally contented doing the exact same thing? That’s why many of my birding friends put aside birding during the years their children were little.

I was too addicted. Most of the time that was fine—even though I always had my binoculars around my neck when I took my kids for a walk, I was usually good at diverting my eyes from birds to whatever dandelion or spider or dragonfly or colorful rock or shovel truck they wanted me to look at. 

Katie, Laura, and Joey at Hawk Ridge

In 1988, when they were 3, almost 5, and 7, we took a three-week family road trip to Washington, D.C., where Russ had a meeting, and then to Florida, where we stayed in the campground at Fort Wilderness at Disney World for a few nights and then Everglades National Park for a more genuine camping experience. I was mostly on my own with the kids in DC while Russ was focused on work, but every day we all told him about our adventures. 

At the Natural History Museum, I tried to be as patient looking at the dinosaurs as the kids were looking at the bird displays. And we spent a lot of time, both coming and going, right outside the museum entrance in the Washington Mall, where the kids could play with Uncle Beazley, a fiberglass statue of the Triceratops in Oliver Butterworth's children’s book The Enormous Egg. (At that time, children were allowed to climb all over Uncle Beazley, but in 1994, the statue was moved to the National Zoo, and children are no longer allowed to climb on it.)

Our visit to the National Zoo was fun for all of us even if our eyes weren’t always focused on the same things. The kids were thrilled with the animals in the enclosures as I paid more attention to wild mockingbirds and Black-crowned Night-Herons living on the zoo grounds. 

From DC, we stopped overnight at Titusville. I got up early in the morning to bird along the wildlife drive at Merritt Island while Russ and the kids slept in—I got several lifers before breakfast! (Sadly, that motel is where we forgot our copy of The Enormous Egg, but fortunately, it's also where we'd finished reading it.) Then we headed to the Kennedy Space Center. I spent a bit of time birding near the parking lot but didn’t see anything I hadn’t seen in the morning, so I checked out the museum too. We all got to touch a moon rock, which was most assuredly worth taking some time out from birding to do.  

We had a picnic lunch at Cocoa Beach, and then Russ and the kids waded, skipped rocks, and built sand structures while I stayed rooted at my spotting scope reveling in my lifer Northern Gannets. My attention was divided enough to be aware of all the giggles coming from them, keeping a smile on my face even as they exulted in my pleasure in seeing my long longed-for gannets.

Then we went to Orlando. As usual, I got up before Russ and the kids each morning to walk around the pseudo-wild grounds of Fort Wilderness. Feral Muscovy Ducks were everywhere, but there were also lots of White Ibises, mockingbirds, Carolina Wrens, cardinals, and Palm and Yellow-rumped Warblers. At the theme park, Russ and I had to split up for many of the rides—Tommy rode on Dumbo three times, though it seemed to have the longest lines of all, and Joey was the only one who reached the minimum height for Space Mountain. I of course had my binoculars on, and couldn't help but notice the many vultures circling optimistically above that long, long line to Dumbo, but I mostly focused on the kids. 

On the drive down to the Everglades, we took a detour on the Tamiami Trail for me to look for my lifer Snail Kite and Limpkin from a restaurant parking lot while the kids and Russ ate lunch. Waiting for me to spot one was boring for them and not all that fun for me—I didn’t see a Limpkin at all and my Snail Kite was just barely within the distance of conjecture. Oddly, or maybe not so oddly, the kids seemed more sad about me missing a lifer than distressed about their own boredom even as I felt more sympathetic about their boredom than disappointed about the Limpkin. 

Tommy in the Everglades

The Everglades were wonderful for everyone, especially the Anhinga Trail, where alligators and ginormous, colorful grasshoppers and orb-weaving spiders competed with the large, colorful wading birds for everyone’s attention. 

Eastern Lubber Grasshopper

Katie was badly allergic to mosquito bites, so while I hiked the Snake Bight Trail, Russ took the kids down to Flamingo. They had fun adventures, and were thrilled to hear about my own slightly scary encounter with a huge alligator blocking the path and my wonderful lifer—a Mangrove Cuckoo I’d never have even noticed except for some excitable Blue-gray Gnatcatchers swearing at it. 

By our last day, I’d still not seen a Limpkin. They are often active and vocal after dark, so we went back to the Anhinga Trail after our last dinner in our tent. Mosquitoes were thick so Russ stayed in the car with the kids listening to Raffi songs while I walked to the boardwalk and quick success. Russ and the kids seemed almost as thrilled about the lifer as I was, perhaps especially because I was so expeditious in seeing it. 

When we got home, the very first thing the kids told their grandparents about—the highlight of the entire trip to Washington, Disney World, and the Everglades for them—was the women’s bathroom in the Everglades campground. Throughout each day, colorful tree frogs gathered in the sink drains and toilets, and one large toad spent each day hunkered down in the corner nearest the door. We’d of course shepherd the frogs out of the toilet before using it, and were very careful to run the water in the sink slowly to not disturb the frogs in the drain. We wrote a song about them with many verses, but I can only remember one:

There's a tree frog in the toilet, in the toilet. 
There's a tree frog in the toilet, in the toilet. 
Please don't flush or you could spoil it
For the tree frog in the toilet.
There's a tree frog in the toilet, in the toilet. 

 I still wish the park had posted an identification poster—there were several species there—but one of the naturalists told me that for most visitors, those frogs were not a feature but a bug. 

In 1990, we went to the Black Hills and Badlands of South Dakota. The kids were especially looking forward to visiting Rapid City’s Dinosaur Park and Storybook Island. I managed to stay engaged with paleontology at the one, but as we were piling out of the car in the parking lot for Storybook Island, I heard a Black-throated Grosbeak—a lifer! I figured I’d catch up in just a few minutes, but there were so many birds along a stream running alongside the parking area that I ended up not getting into the park until they were almost ready to leave. The funny thing is, I had a wonderful time listening to their stories about what they saw, and they thoroughly enjoyed hearing about the cool birds I saw, especially my lifer. 

The next year, I took a Minnesota Ornithologists’ Union birding trip to Texas without my family—I badly wanted to get my life list up to 500 before I turned 40. I got 20 lifers, but the biggest thrill of all was when I came down the jetway after the flight home. There were Russ and the kids holding up a big banner they’d made, saying “Welcome Home, Mommy” with a huge, colorful "517!"—my new life list total. 

In 1993, we took another road trip to visit some of Russ's family in New York City and Long Island. We told everyone to pick one or two places they most wanted to visit en route or in New England. Joey, who had just memorized Longfellow's incredibly long "Paul Revere's Ride," wanted to visit some of the places mentioned in the poem. Katie wanted to see Niagara Falls. Tommy wanted to go to the top of what he called the Stachuke of Liberty. I wanted to visit three places—Grayling, Michigan, to go on a Kirtland's Warbler tour; Walden Pond; and Machias Seal Island to see my lifer Atlantic Puffins. Russ wanted to visit a close friend in Concord. 

Kirtland's Warbler
What I promised

Somehow, everyone's choices were fun for everyone except my Kirtland's Warbler tour. I'd overhyped the "Bird of Fire" and how easy it would be to see it, based on the trip there Russ and I had made in early June 1976. Now, at the very end of a different June, it was hot and muggy, and most males were too busy feeding young to sing much. None of us, including our guide, saw any until near the very end of the two-hour hike, when I saw a male singing at treetop height not too far away. Unfortunately, at that very moment he finished singing and flew off. The kids got a quick, unsatisfying glimpse of him darting away, and poor Russ didn't see him at all. And for all that, the bird wasn't even a lifer for me. 

Kirtland's Warbler habitat
What everyone saw

After that, the kids kind of rolled their eyes when I waxed euphoric about puffins. But in Maine, the actual event far, far exceeded even my own expectations. Family time in the observation blind at Machias Seal Island turned out to be one of the biggest highlights of the trip for everyone, the puffins just a few feet away, some even padding on the plywood roof. 

Piggy and Tommy looking out the blind at the puffins and razorbills on Machias Seal Island

Atlantic Puffin

Atlantic Puffin and Razorbill

In 1995, we traveled to Yellowstone National Park. Russ and the kids did a lot of serious hiking while I moseyed about looking for birds. On two loop trails, they lapped me, on one going around three times before I made it around once. We spent a lot of time waiting for Old Faithful to erupt, but it was fun for all because adorable little marmots—chunky rodents—swarmed about the boardwalk. Visitors were prohibited from feeding them, but the hopeful little guys came bizarrely close for petting, and one took a particular liking to Tommy. I spent my time watching Violet-green Swallows flying about. We visited Old Faithful twice because Russ wanted to make sure his camera settings were right for the geyser, and both times, a Mountain Bluebird alighted near the geyser a few minutes before it erupted and then, right before the water started gushing, it flew right toward us and hovered, an adorable little park guide making sure we were all looking in the right direction just before the gush. After the eruptions, it disappeared, apparently going on break until the next eruption. 

Yellow-billed Magpie

In 1996 we took our longest road trip of all, to California. We did all kinds of fun things for everyone, from the San Diego Zoo all the way up to Alcatraz. My only hard-and-fast birding goal was to see a Yellow-billed Magpie. We'd planned to spend a couple of days near Santa Barbara, and one of my friends told me it would be impossible to miss these splendid birds at Nojoqui Falls County Park. Unfortunately, the falls, and the birds, are apparently seasonal. We hiked through the park three times but didn't see the waterfall, the magpies, or much of anything else. I did finally add that lifer when we were headed to San Francisco—the only lifer I've ever seen without binoculars while going close to 70 miles per hour. 

In 2000, over winter break during Joey's senior year of high school, we took our biggest family trip of all, to Hawaii. There were so many wonderful adventures for all of us, but no matter what else they were doing, the kids were hellbent on finding a Hawaiian Goose for me—a most yearned-for lifer. Russ was the one who spotted it first, and they all felt triumphant.  

Hawaiian Goose 

Even since that "final" family vacation, the five of us have gathered together in Florida a few times. Lake Kissimmee State Park was a favorite destination for everyone when Florida Scrub-Jays still greeted visitors at the entrance. This wonderfully friendly and charismatic bird is declining dangerously, but Florida developers have done their best to keep the species off the Endangered Species List.

Florida Scrub-Jays and Joe

I’ve been thinking about all this because Katie and Michael invited Russ and me along on a family trip to the Gunflint Lodge this Presidents Day weekend. I spent hours watching and photographing the many birds at the nature center while the rest of them visited a playground and a wonderful sledding hill. Back at our cabin, I parked myself on a chair by a window where I could sneak peeks at the birds at the feeder even as I played with Walter. 

Pine Grosbeak

After the trip was over, when we asked him what his favorite part was, I naturally wanted him to say the birds—he really had been taken with the big, pink Pine Grosbeaks and the teeny tiny yellow American Goldfinches right outside our window. Katie, Michael, and Russ of course hoped he’d say the sledding, or at least the slide in the playground. But nope. The biggest highlight of all for Walter was watching some men fixing the engine on a snowmobile. 

Families have fun together, I told them from the heart. Whether we play together or apart. 

Heading out for sledding and skiing!


Friday, February 17, 2023

Earning Trust in the Age of Climate Change

Ruffed Grouse
Ruffed Grouse often bury themselves in deep snow for the night. Yeah, it's cold, but on frigid nights the temperature under thick snow is higher than the air temperature and there is zero wind down there. 

My son-in-law, still adjusting to life in northern Minnesota, plays on an outdoor curling team. His game has been cancelled three weeks in a row, two weeks ago because it was double-digits below zero, the following week because it was so warm the ice was melting, and this week because it was raining. At this very moment, as I write this, temperatures are back below zero but are expected to rise into the 20s today. 

This weather is of course not “normal,” but when it comes right down to it, no winter is normal anywhere—there are always days, and sometimes entire seasons, that are significantly above or below the average for temperature and precipitation. I know one TV weather forecaster who was still insisting, last time I talked to him a few years ago, that climate change is a hoax, citing every recent cold weather event as “proof.” It must be getting harder and harder for him to make that case—in the century and a quarter from 1895-2021, the daily average minimum temperatures during winter (Dec-Feb) have increased 4.9 degrees in southern Minnesota, 6 degrees in central Minnesota, and an astonishing 7.3 degrees here in northern Minnesota.   

That does not mean winters are growing milder. Even though we’ve not had enough cold for Lake Superior to freeze this year, the wild swings are extremely hard on wildlife and humans both. A January snowstorm took out several of my daughter’s trees, ice dams have been a huge problem for a lot of Duluth houses, and rock-hard ice on top of deep snow makes vole hunting difficult for owls, plunging under the snow for shelter hard for grouse, and walking hard for deer.   

Gray Squirrel

Yesterday when a backyard squirrel, all plumped up with its tail snugly wrapped over its back, looked trustingly at Walter and me through my dining room window, I cranked the window open and Walter tossed it some peanuts. He was delighted that the squirrel instantly ran up and grabbed one to carry to a nearby branch where Walter could watch it eating. As soon as it finished the peanut, it ran back below the window and grabbed another.   

Walter is 2 ½ now, and understands that squirrels, bunnies, and backyard birds all live outdoors. They can’t come in the house to warm up, but they don’t need to—their fur or feathers keep them warm as long as they have enough food. I love that he’s developing empathy, taking joy in making sure our squirrels have that food. Compassion begins with self and family, but then circles out to include friends and neighbors, including backyard wildlife. Cultivating empathy and compassion for these inner circles helps ensure that little by little it will flow further outward.   

Mourning Doves

Walter and I also watched the two Mourning Doves who have been visiting my yard fairly regularly, especially on the coldest mornings. They are obviously counting on my feeder, but the fact that they don’t come every day is evidence that they have at least one other refuge somewhere near here. They’ll almost definitely get through the season in fine fettle, but I still get anxious on the coldest nights knowing how vulnerable their fleshy feet are to frostbite. I haven’t told Walter that—just reassured him that they have lots of bird seed in that feeder.  

Kelli Alseth's dove

Kelli Alseth, in Proctor, has been seeing one lone Mourning Dove every single day since early January, and every day she makes sure the bird has sunflower chips and white millet in safe, fairly secluded spots near her house. Kelli notes that the little dove has a few favorite places for eating and for roosting, including some in full sun and some sheltered from the wind. 

Kelli's dove knows where it'll be warmest depending on sunlight and wind. 

We know that Kelli’s dove relies on her yard because it shows up every single day at dawn and dusk—the two most critical times for wintering birds to fill up on food. Her conscientiousness toward that one little soul tells me a lot about what kind of trustworthy and compassionate human being she is—the kind I so want my little Walter to become.  

Meanwhile, Russ and I are doing everything we can to make Walter’s future as safe as possible even as climate change continues apace. Last fall we bought a heat pump, and we’re going to be installing solar panels as soon as the snow is gone this year. Being in our 70s, we won’t recoup the financial investment in our lifetime, but profits and dividends aren't always measured in dollars, and by any measure, burning less carbon is a Good Thing. No individual can make much of a difference in a global problem that is so big and so deep and so tall, but doing what we can makes me feel at least a little worthy of my grandchild’s love and trust. 

VIP at my book signing

Wednesday, February 15, 2023

Birding Basics: Binoculars

Laura's new binoculars! 

Binoculars are essential equipment for birding, but a lot of people get frustrated trying to get birds in their binocular view before the birds fly. When I went out on my first birding jaunt, on March 2, 1975, I was using brand-new Bushnell 7x50 binoculars. They weren’t expensive even for back then, but with their huge field of view and extreme brightness, I never, even from the start, had trouble finding birds in them.   

Those binoculars were a gift, and although they were extremely heavy, they were my passport to the whole new world of birds. A year later when I took my second ornithology class, I was asked to assist as a leader on some field trips, entitling me to use the university’s top-of-the-line Leitz 10x40 binoculars. They magnified birds 10 times rather than 7, and were smaller and lighter, the objective lens 40 mm instead of 50 mm. They were a noticeable improvement because of their superior manufacturing, but I had no trouble handing them back after each outing, happy to return to my own beloved pair.  

Me looking at my lifer Kirtland's Warbler
Looking at my first Kirtland's Warbler through my trusty Bushnell 7x50s.

Tragically, a few years later the cheap plastic neck strap snapped and my binoculars hit a rock, knocking them out of alignment. At this point I was ready for something lighter, but I made the mistake of going too far, getting Minolta 8x25 pocket binoculars. No one told me that the tiny objective lenses of pocket binoculars don’t let in enough light in early morning and late afternoon or in forested habitat, and are especially worthless for twilight or night birding, nor that the combination of higher power and narrower field of view would make it harder to find birds, though I used them so often that I quickly adapted to that. I do wish I’d known the longstanding rule that the diameter of the objective lens in mm should be at least 5 times the magnification power—that is, 7x35, 8x40, or 10x50.   

Optics have improved enormously since the 1970s, but that 5-times rule still is very important for inexpensive binoculars that lack the sophisticated coatings of pricier models. Even in top-of-the-line models, the second number should never be less than 4-times the first.  

For beginners, I strongly suggest a magnification of 7x or 8x. For any given model, that provides a much brighter view, less binocular-shake, lower weight, and a bigger field of view than 10x. It’s very important to use our binoculars a lot, pulling them up while keeping our eyes directed toward the bird. Practicing on stationary objects at first helps us discern whether the view through our specific pair of binoculars will land directly on, slightly above, or slightly below where our eyes were looking—this practice pays off when a good bird flies seconds after we spot it with our eyes.  If you wear glasses, make sure the binocular eyecups are all the way down, putting your eyeglass lenses close to the binocular optical lenses. Those eyecups are designed to hold the optical lenses a precise distance from your eyeballs, but eyeglasses hold the binoculars about the right distance without the cups. 

One very important rule for buying binoculars is to get the best model you can comfortably afford. Coatings and lens materials have improved enormously since I started out, and binoculars at every price point are better than they were half a century ago, but remember that for optics, the relationship between cost and quality is not linear. The jump in quality between $50 and $250 binocs is huge compared to the difference in cost. The jump in quality between $250 and $3,000 binoculars is huge, too, but not nearly as significant as the jump in cost. Top-of-the-line Zeisses or Swarovskis are definitely better than just about anything, but the biggest differences are hardly noticeable except for people who use their binoculars for long hours every day. For most of us, the difference between $250 binoculars and $3,000 binoculars could pay for a wonderful trip to see a lot of birds.   

Chandler Robbins in Guatemala
I took this photo of Chandler Robbins, my birding hero, in Guatemala in 2007. Back in the 1970s or early 80s, one of his friends made a protective leather cover for his binoculars, the same brand and from about the same era as my original Bushnells, and he stuck with them lo those many years, spending his money not on upgrading his optics but on important conservation projects to protect the birds he loved. When people gave him "better" binoculars, he usually gave them away to deserving birders in the tropics.

My focus has always been more on birds than on equipment, and I have no idea what products are out there anymore, so I asked one of my dearest friends, who is objective and knowledgeable about the current optics market, about his current recommendations. His top four favorites, all 8x42, as of February 2023 are: 

Vortex Diamondback 

Kowa SV II 

Opticron Natura BGA 

Kowa BD II XD 

When you’re in the market for binoculars, the very best way to test different models is at birding festivals. Representatives from manufacturers and retail companies encourage people to test their wares, often from an outside booth where you can look at real birds in natural conditions. If you know what your budget is, try to discipline yourself to test only models at or below your max. 

Once you have the binoculars you'll be using for a while, the most important thing is to stop thinking about optics and just use them. After all, the whole point of birding binoculars is to focus on birds.

These binoculars have seen a LOT of birds!
I took this photo of Chandler Robbins's binoculars, which he was still very satisfied with, at lunchtime when we were in Guatemala in 2007. 


Monday, February 13, 2023

Superb Owl Sunday 2023

Boreal Owl

Russ and I don’t get to go birding together very often, but we do make a point of getting out one particular Sunday in February whenever we can—Superb Owl Sunday, which I made into a personal annual tradition back in the 1980s. Some years I haven’t been able to go birding, and many times Russ’s schedule hasn’t allowed us to celebrate together, but the very best owl photo I ever took, of the most cooperative Boreal Owl in the most perfect light ever, was on Superb Owl Sunday 2013. That was during my Big Year, and it happened on the only day that whole year that Russ and I could get out together.  

Boreal Owl

This year hasn’t been great for finding owls at the Sax-Zim Bog—I suppose I could blame it on something trendy like supply chain issues, but some winters owls do just fine further north and don't show up here. People up at the Bog have seen a Great Gray Owl every now and then this year, but the birds are apparently finding enough food at night that they don’t need to sit out in the open by day. Great Gray Owls don’t mind people too much as long as we don’t approach uncomfortably close, but ravens and crows can be very rude when they spot a Great Gray, so the big owls prefer to hide out by day if they’re not too hungry. On my two trips to the Bog so far this year, I haven’t lucked into a Great Gray.  

Great Gray Owl
I took this photo on Superb Owl Sunday 2019.

I did get fairly nice if somewhat distant looks at a Barred Owl at the bog this year on New Year’s Day. 

Barred Owl

Then on January 31, a Great Horned Owl turned up in my own yard in early afternoon, sitting in a very exposed limb in a big deciduous tree for several minutes. The bird seemed to be actively hunting, noticeably checking out the neighborhood squirrels and my little dog Pip, so I instantly brought her (the dog, not the owl) indoors. Great Horned Owls start nesting in January and February up here, so I’m assuming this was a male searching for food for his mate and, if they’ve already hatched, his tiny nestlings. No way could a Great Horned Owl carry off an 8-pound dog, but he could easily kill her and then eat her in place or carry off chunks for his family. I think the local pair is nesting somewhere near Lester Park. 

Great Horned Owl

On February 9, I noticed crows harassing a different Great Horned Owl behind my daughter’s backyard—that owl was roosting and trying to evade the notice of any local crows. It was too tucked against the trunk for Walter to pick it out, and the crows drove it off before my son-in-law Michael made it to the window. Any glimpse of an owl should be plenty good enough for me, but I was still disappointed that Michael didn’t get to see it. 

That was it for owl sightings in 2023, so I was filled with eager anticipation on Superb Owl Sunday. Russ and I headed to the Bog, and sure enough, one of our very first birds of the day was a Northern Hawk Owl. It was extremely far away—almost beyond what Pete Dunne calls the distance of conjecture—so wasn’t at all satisfying from a photographic standpoint, but in birding as in baseball, a win is a win, defined on Superb Owl Sunday as seeing any owl. 

Very distant Northern Hawk Owl
That teeny tiny speck at the top of the tree right in the center is a Northern Hawk Owl. Really!

Even better, owls are not the only birds, and we saw plenty of birds up close and personal, especially one of my all-time favorites, Evening Grosbeaks, which were visiting all the feeders. 

Evening Grosbeak

Evening Grosbeak

Evening Grosbeak

Their pleasant chatter formed so much of the soundtrack of my life for the lovely decade when my children were little, back when Evening Grosbeaks were abundant here, that hearing them is balm for my soul. I’ve made long stereo recordings from my house (all listed on my Evening Grosbeak page), but couldn’t help but hold my phone up for a 2-minute recording behind the Visitor Center.

Evening Grosbeaks way outnumbered Pine Grosbeaks, but both species gave me lovely photo ops. 

Pine Grosbeak

Pine Grosbeak

One lone Pine Siskin hanging out near a feeder by the Welcome Center outhouse was very cooperative.  

Pine Siskin

Canada Jays in several places were just as cooperative.  

Canada Jay

Canada Jay

We came home happy and satisfied with our beautiful day of birding.

But Superb Owl Sunday wasn’t over yet. My dear banded Pileated Woodpecker BB showed up soon after we got home, and SheB (the female who may or may not be BB's mate) came soon afterward. And then, what to my wondering eyes should appear but a little Brown Creeper hitching up my box elder. I was right in the middle of downloading photos from my camera’s card, but even if the camera had been ready for shooting, the little bird was focused on eating, not accommodating my photographic needs. I didn’t care—like I said, a win is a win.

Northern Hawk Owl
This photo was taken in January 2011--not on Superb Owl Sunday, but a Superb Owl nonetheless. 


Friday, February 10, 2023

A Few Conifer Specialists

Kirtland's Warbler

The relationships between birds and plants are wonderfully complicated. Just about every bird I’ve ever seen in my yard has spent at least a little time in my conifer trees.  But a few birds are so specialized that they require conifers —sometimes even a single species of conifer—during an essential part of their annual cycle.   

For example, Kirtland’s Warblers are extremely tied to jack pines. On their wintering grounds in the Bahamas, during migration, and even on their breeding territories they find plenty of insect food from a variety of plants, but they nest exclusively on the ground beneath the sheltering bottom branches of jack pine trees. Males aren’t too fussy, but females are—one won’t even consider nesting until she finds a jack pine between about 5 and 15 years old and roughly 5–15 feet high. Too young and a tree won’t provide enough shelter for the nest; too old, and the bottom branches have fallen off, again leaving the nest too exposed. 

Kirtland's Warbler habitat
Ideal Kirtland's Warbler habitat near Grayling, Michigan

Jack pine cones open only when subjected to extreme heat—historically from natural wild fires. Now, with so many humans encroaching on their small natural range in northern Michigan, Kirtland’s Warblers depend on extensive management to ensure there are always stands of acceptable jack pines for them. 

Female Kirtland's Warbler at Magee Marsh
This fussy female Kirtland's Warbler was photographed at the Black Swamp Bird Observatory's Magee Marsh in Ohio during migration. No jack pines available, but she's not nesting yet anyway. 

Crossbills nest in conifers, but it’s their feeding habits that make them such extreme conifer specialists. They get their name from the way the lower bill crosses under the upper, either toward the left or toward the right—an adaptation that allows them to insert the bill between cone scales and then twist the lower mandible towards the side to which it crosses, enabling the bird to extract the seed at the bottom of the scale with its tongue. 

White-winged Crossbill

Whichever way a bird’s lower bill crosses determines the side of its face that must be close to the cone. Intriguingly, just about exactly half of all Red Crossbills are left faced and half right faced, but about 75 percent of all White-winged Crossbills are right faced. That difference reflects their cone choices. 

White-winged Crossbill

White-winged Crossbills specialize on spruce and tamarack cones, which tend to be smaller and less sturdily attached to the branches than pine cones. White-winged Crossbills feed on cones still adhering to the trees, but if a section of cone is too hard to access for, say a right-faced bird, it can simply snip off the whole cone and rotate it in its foot, to get out all the seeds. White-winged Crossbills also feed on cones that have fallen to the ground, again easily rotating the cones to extract the seeds. In this species, the lower bill crosses to the right in three times as many individuals as the other way around—about the same percentage we’d expect assuming the way a bill crosses is due to a simple dominant or recessive gene. 

Red Crossbill
Yeah, Red Crossbills usually feed in pine trees. This one is picking up grit to help it digest those pine seeds and give it some minerals the seeds lack.

In contrast, Red Crossbills specialize on pine cones, which usually remain firmly affixed to the tree even as the seeds are pulled out, so Red Crossbill individuals miss a lot of seeds under scales that happen to be too close to the branch to access, depending on which way their bill crosses. Crossbills hang out in flocks, and for them to maximize the number of seeds for the entire flock, it makes sense that the bill crossing is 50/50, though scientists have not figured out how this is controlled genetically. 

Red Crossbill

When I worked at the Cornell Lab of Ornithology, I checked out the specimens in their collection. In Red Crossbills, it’s supposed to be 50-50, and sure enough, 22 of 41 Red Crossbills crossed one way, 19 the other. But in White-winged Crossbills, a much higher percentage of birds have lower bills crossing to the right than to the left—in the Cornell birds it was 32 of 46 birds, or 70 percent. This kind of ornithological trivia is a little too specialized to ever make it into the TV game Jeopardy!, but I think it’s fascinating.

Tennessee Warbler

Cape May Warbler

Bay-breasted Warbler

Some birds depend on conifers for food even though they don’t eat seeds at all. Tennessee, Cape May, and Bay-breasted Warblers feed voraciously on an insect that feeds on spruce and fir needles in northern forests: spruce budworm. 

photo by Jerald E. Dewey, USDA Forest Service, http://www.forestryimages.org/browse/detail.cfm?imgnum=2252020

This moth larva, considered a serious pest by foresters, is so important for these birds when feeding young that their populations fluctuate with spruce budworm population cycles. Evening Grosbeaks also depend heavily on spruce budworms for feeding their nestlings.  

 Evening Grosbeak

The more I learn about the fascinating connections between birds and plants, the richer my world becomes. 

Evening Grosbeak