Bird Research with Raul Mandujano (by Ian Paul Markham, Coordinator)
31 July 2017
Work with the bird team began in the wee hours of the morning before dawn. The roaring of red howler monkeys as the first light crept into the jungle provided a screen of sounds that gave some chance that the herpetology team, having recently returned from late-night transects, might sleep through our commotion as we groggily packed up our equipment. As the dawn chorus began to warm their vocal chords we plunged into the jungle at a purposeful clip. The aim was to get to our sampling site and get set up before most of our target species would wake up and be alarmed by our presence.
After perhaps a two-kilometre hike up the main trails, up and down a few hills, under some fallen trees, and across several small streams we arrived. Raul Mandujana Collantes, our bird team coordinator, and I headed down a side trail for the first set of mist nets while the two volunteers Tom Waters and Megan Wampler headed for the other two. We quickly opened the three to four mist nets waiting at each site, with each net stretching about twelve meters long and four meters high. The “mist nets” are so-called for being almost invisible with their thin, dark mesh when opened, ensuring that birds flitting through the understory won’t spot them until it’s too late. With the nets opened we returned to our bird processing station to wait.
I had expected, as in mist-netting experiences previously, to find a rough machete-cleared spot in the forest, perhaps with at most the luxury of some ponchos spread on the ground for a cleaner seat. Much to my surprise sitting in the middle of the trail was what appeared to be the set up for a tea party. Tom who had gone ahead of us on the trail had set up a foldable table and four chairs, which felt highly civilized given the context. While we waited for the first half-hour we sat, sipped on peach juice, and nibbled contentedly on cereal bars.
Soon it was time to spring into action. The nets Raul and I checked first were empty but Tom and Megan both quickly called in on the walkie-talkies. Megan had a single bird. Tom had quite a situation on his hands. Two grey ant-wrens, delicate little birds that follow around groups of army ants eating the insects that are flushed out of hiding by the hoardes, had flown into the net nearly on top of each other. Closer inspection revealed them to be a male and female almost certainly a mated pair. And just a meter or so away another larger bird had already gotten itself incredibly tangled in the thin line. Taking a brief moment to be touched by the dedication of an avian spouse that would rush headlong after its imperilled mate into a net, Tom and Raul quickly set to work deftly untangling the ant-wren couple from the net. The key is to determine from which side they bird hit the net then carefully disentangle their feet, wings, and whatever else might be trapped. They were soon untangled and put temporarily in cloth bags.
The third bird proved more of a challenge. On closer inspection he turned out to be a Screaming piha (Lipaugus vociferans). These birds are amazingly shy but are a distinctive and ubiquitous part of the Amazon soundscape. Their call consists of three rising whistles followed by something between a whipcrack and a laser beam. It’s such a classic jungle sound that Hollywood movies will often throw it into the background of scenes from all over the world just to give that authentic jungle feel regardless of whether it’s supposed to be in the Amazon or Southeast Asia or Central Africa. But that was not the sound he was emitting at the present moment. He’d gotten into quite a tangle thrashing around and even manage to get his tongue with its bizarre backwards-curved barbs tangled in the net. Disentangling the frantic bird was quite a challenge but Raul patiently set about it patiently with skilled hands.
With our first set of birds we returned to our processing table and got to work collecting data. A surprising amount can be learned about a bird in hand. For example, by getting the feathers on the crown of the birds head a damp and looking at the colour of the skin underneath one can determine the stage of development of the skull and thus an approximate stage of development. Or by blowing lightly on the birds breast one can look for extra feathers called brood patch and fat deposits indicating the bird is nesting. Moreover, by adding an individually coded metal band to the leg of the bird one can track individuals through time and rates of recapture to help get a sense of the local population through time. All these measurements take time though and collecting all this information while stopping every 30minutes to dash back to the nets and collect more birds makes for quite a busy morning!
The birds arriving into the nets ranged widely in size, colour, and levels of cooperativity. A chestnut-winged foliage gleaner that we caught was a particularly tough customer. His sharp little beak would latch onto anything he could get hold of. What’s worse was that he seemed to figure out what caused pain and what didn’t. As I tried to distract him with various inanimate objects he learned one by one that going back to latching onto Megan’s fingers was much more effective than biting pencils or tubing. Her stifled whimpers and cries of dismay as she carried on collecting the data were painful in their own right.
The highlight of the morning, however, was certainly the Green-and-gold tanager (Tangara schrankii). This gem of a bird is normally found high in the canopy, just a dark silhouette against a bright sky, so catching one in the very top of the net was a real treat.
At around 10 am it was time to close up the nets and call it a day. We caught a total of nine birds, a pretty good haul considering we were still coming out of a cold front. After releasing the last bird, tired but satisfied we packed up our picnic tables and returned to camp.
If you want to read more about Ian's adventures in the natural world, visit his website: https://wildhopecollective.com