In China, ornithologist Sam Snow and his colleague gather as much data about a species of bird as possible -- but it comes at a cost.
Sam Snow is an evolutionary biologist and ornithologist, currently a Ph.D. candidate at Yale University. He looks at birds to explore the evolutionary consequences of mate choice for sexual ornamentation, mate-system evolution, and social behavior. His research seeks to understand how females evolve new traits that overcome sexual coercion, reshaping mating systems and male social behavior. In search of answers, he creates theoretical computer models of behavioral evolution and attempts to test these theories by documenting the behavior of birds in the wild.
This story originally aired Oct. 27, 2017.
Story Transcript
The first time I held a wild bird in my hand, felt its feathers, its heartbeat, looked in its eyes was magical. That’s not very scientific. But think about it. Birds are defined by their untouchability. It’s impossible to get close to them. You chase them, they run away. They're up in the trees, they're in the air, and they look so fragile.
I was in college and I was in an ecology course and we were learning how to use mist nets, were these really fine nets that birds have trouble seeing. We’re using them to safely catch and release them for research.
Scientists use these for a lot of reasons: to count birds on their migrations, to get blood samples for DNA analysis, or to mark individuals and release them so you can identify them later for behavioral research.
Like most other people, at this point in my life -- normal people, that is -- I didn’t pay much attention to birds at all. But this experience, holding one in my hand, totally changed the way I looked at birds and all I wanted to do was learn more.
So after college, I became a field technician. I went around helping graduate students with their projects on birds, working long hours usually in exchange for some sandwiches and a place to sleep. It took me everywhere. I went all over the place including a four-month stint in rural China working on a project on the migration and breeding behaviors of a particular sort of crow-like species of bird.
At that time, it wasn’t known where this species actually migrated to after they bred on the breeding grounds in China. And this information is actually really important for conservation purposes, obviously.
We were also interested in where they were deciding to build their nests and what factors influence most their successful breeding, for example, like parental care.
My boss was a Chinese graduate student. Let’s call him Lee. Lee was pretty intense. We worked from five a.m. to ten p.m. every day, and the whole four months I think I got only about three days off. But he made it really fun and he was really a good-natured guy and he was really patient with me.
My Chinese is garbage and we would argue every night about watermelon. I’m a normal person. I like watermelon, but he would, every night, we would be like at ten p.m. about to go to sleep and he’d come in with this big watermelon, open up the whole thing and we’d be like, “Oh, we’re tired.” He'd eat a couple of pieces, then throw the rest away. It drove me nuts. We were wasting watermelon.
And I'd be doing something like trying to stash the watermelon away, like cut a little off and just eat that little bit and he'd come over me, like enjoying and cut up the whole thing. It wasn’t until I got it through my thick skull and realize that, actually, he was being really generous and caring. In Chinese culture, the way you show that you really care is by always providing more than your guests need.
The first time that we clashed about something that wasn’t watermelon-related was about micro GPS trackers. So these things are really cool and the technology is only recently becoming feasible to use on really small animals like birds. So the way we use it is it goes on like a little backpack and then it periodically records GPS positions. We’re going to use this to figure out where the heck they migrate to.
Unfortunately, the company made a mistake and they were way too large. So the standard for using these kind of equipment on birds is that they should be less than two percent of the mass of the bird. We were up at ten percent. That’s seven grams for a seventy-gram bird.
It was obviously problematic. I, as the resident native English speaker, spent hours on the phone with the company trying to convince them to send us new tags. They screwed up. Unfortunately, they didn’t believe us. They thought that we were lying to get free tags from them so we were stuck with like a dozen inappropriate, way-too-big, custom-made GPS tags that cost about ten thousand dollars.
It was Lee’s project and that would have been a lot of money to waste, so we used the tags.
Look, migration is hard enough without a huge weight on your back. And we learned later that nearly all those birds died.
Other issues that came up had to do with the way that we would capture the birds. Remember, we wanted to know where they’re migrating to, who’s involved with parental care, who’s helping build the nest. So the entire project hinged on capturing as many of the birds in population as possible and putting little color bands on them to mark them as individuals so we can see them later.
Mist netting adult birds is pretty tricky, sort of not surprisingly. You have to carefully plan where you put the net, you have to monitor it regularly and you have to wait really patiently until the bird flies in, which it might never, ever do. So, to avoid all this hardship, one thing we would do is we would tag the nestlings.
So the way this works is we’d monitor a nest and then wait until just before the babies were about to fledge, which is to say fly out for the first time. We’d shake the branch and they’d come to the ground, we collect them, put bands on them, put them back up in the nest so that when they're adults they’ve got bands and we can look at them.
One time, two of the babies came out, but one of the three wouldn’t budge. Now, were using these lightweight telescoping fly fishing poles. I don't know if you guys have ever seen these, but they're like ten meters long. This is what we’re using to smack the branch. And after a few minutes of Lee whacking away at the branch and this guy is like standing there under the branch not moving, I’m like, “Oh, well, you know, you win some, you lose some. Come on, Lee, let’s get out of here.”
And he's like, “No. I can get ‘em down and I don't want any missing data. This is really important.” I’m like, “Okay.”
So he's whacking and whacking and whacking and whacking the branch and it does flutter down. We walk over and collect it and, to our horror, unfortunately, we realized that the reason it fluttered down is that Lee had accidentally broken both its legs.
So knowing what I know now and having the training that I have now, I probably would have chosen to euthanize it right there and end its suffering, but, heck, I'd been at this for only a couple of months. I had no idea what to do. I was scared, I deferred to Lee and he was really upset too. Don’t get me wrong. But we nonetheless did go ahead and put a band on it and we just kind of left it in the bush because it couldn’t perch to be raised back up to the nest.
I headed back the next day to check on it but, of course, it was gone. Sorry, it doesn’t actually get better.
The final straw came not too long after. I mentioned that mist netting adult birds is tricky. One thing we could do if, for example, some adult birds made it all the way through most of the breeding season while remaining unbanded is we could use their babies as leverage. The way this would work is when we would band the nestlings we’d actually set up a net right there, and then put the nestlings on a branch on the other side of it as bait and then the parents would come to feed them or defend them. Unsurprisingly, this works pretty well.
Obviously, this puts the birds in a pretty vulnerable position. In an ideal world, you would sort of stay hidden and then wait for the bird to just fly in and then you come out and release it immediately. In this case, in the interests of increased efficiency, we were running several of these nets simultaneously at different points as we’re motorbiking between them.
One day, I went to check on one of these nets just when it was starting to rain and I was already getting really nervous because it’s not good to have the birds hanging in the net if it’s raining. Before I even saw the net through the trees, I could hear this squawking commotion so I started running. When I got there, I couldn’t find the nestlings anywhere and the two adults were caught in the net.
The female was struggling and screaming with the male wasn’t moving at all. I immediately released the female who had been banded already and turned my attention to the male who’s hanging there bloody and mangled. I actually couldn’t find his head anywhere. It seemed like this was a result of an attack by a cat which meant that the babies were probably all dead.
The body was really tangled and I wasn’t about to just cut a big hole in this really expensive piece of equipment so I spent the next several minutes carefully wiping away blood and raindrops as I moved the fibers in the net away from the splinters of the wing and the severed neck. I wrapped the carcass in a handkerchief and I brought it back with me along with the other birds that needed to be banded to the field station.
I felt pretty numb on the way, but when I got there I kind of lost it. I walked in. I didn’t say anything. I dropped the carcass and the handkerchief on the table and immediately turned around and went up to my room and I just cried. I just felt so sad. I know you can’t control random predation events, nobody can, but I know that if we hadn’t been stringing ourselves out too thin and running around checking so many nets, I would have been there to prevent that.
I felt responsible for contriving that whole horrible situation to begin with. That bird was just trying to protect its kids, which I put there as bait, and he got torn to pieces hanging helplessly in a net that I set. That cat just pounced on an opportunity. I made that happen. There's just too much blood on my hands both figuratively and, in this case, literally.
I couldn’t bring myself to work the next day and I finally seriously confronted Lee about this stuff. We talked for a long time and ultimately we reached an impasse, actually.
He said, “Yeah, I feel really bad too. These birds are my life, but I also feel like I have no choice.” He explained to me, “Look, I’m under a lot of pressure here. I have only a little bit of time to finish this really big project and I have to collect as much data as possible and it doesn’t matter that it’s risky. I have to do it.”
I’m a graduate student now with my own dissertation on the line. I study the evolution of mating behaviors and social cooperation in birds and, yeah, I still catch birds as part of my research program. But I understand better now how easy it is to become fixated on a really specific narrow goal, like, “I need to catch fifty birds this week,” “I need lots of data to complete my project.”
I also see how often the academic system puts really good people like Lee in really difficult positions. Maybe if we had more funding security or a more understanding academic culture he wouldn’t have felt so strongly about taking all those risks. After all, all the stuff we did in China it always backfired. We wanted more data and all we got were more dead birds.
Academia, the job market, it is really intense. But I strive everyday to remember that the whole point of doing this research is not to just collect as much data as possible. It’s actually to protect these birds I love and understand them better. So now, I’m okay with letting one go every once in a while. Thanks.