Birds in Their Habitats

by Ian Fraser

  Many stories revolve around people becoming birds on dying, probably the most famous in our culture being the belief, whose origin I cannot determine, among European sailors that their souls transform to albatrosses after death. That one seemed to protect the birds too, at least until long-line fishing was invented.

  Giant mosses and carnivorous pitcher plants vie for attention with the birds – and all provide an excuse for frequent stops on the relentless climb, with sets of steps rising one after the other. A pair of appropriately named Crimson-headed Partridges scurried across the track in front of us while equally red Temminck’s Sunbirds worked the flowers above. As huge front-heavy Rhinoceros Hornbills flew over and busy little Plain Pygmy Squirrels scurried in the undergrowth, a richly coloured pair of Maroon Woodpeckers attacked the rotting end of a broken branch above our heads. They were too engrossed to treat us to their raucous call on this occasion, a call which used to be welcomed by local Dayak raiding parties, because it pre-echoed their own enthusiasm when they relieved one of the opposition of his head (Winkler and Christie 2016). Flocks of pretty little Chestnut-headed Yuhinas, grey above and white below with rusty head, assiduously searched leaves for insects as they passed quickly through. As we climbed higher, Mountain Blackeyes appeared (relatively large green white-eyes with an incongruous black eyepatch), probing their long thin bill into crevices in lichen-enshrouded branches. By the time we stopped for lunch at a small shelter, where Mountain Ground Squirrels and Mountain Treeshrews hung hopefully about, the clouds were descending until we were in a world of mist-wraiths. The mood suddenly grew sombre when a crew of rescuers hurried down the track past us with a still form on a stretcher. More and more walkers crowded into the shelter as the rain exploded onto the forest and our flimsy roof. Every now and then individuals or small groups would accept that it wasn’t stopping any time soon and headed out into it; we eventually did so too, heading down a track that was now a torrent, water rushing over the tops of our boots. The pretty little waterfall near the bottom of the walk was now a roaring foaming maelstrom.

  Back at the entrance station, the rain started to ease off and we were able to retrieve our binoculars from dry-bags in back packs. An immediate reward was a beautiful Golden-naped Barbet scoffing berries in a bush at eye level. Barbets are close relatives of toucans, but without the outlandish bill – chunky medium-sized fruit-eaters, mostly brightly coloured, from Africa, south and South-East Asia and the South American tropics. In Asia and South America they are largely rainforest birds. Until recently they were all lumped into one family, but now they are split into a family for each continent (plus one for the delightful two species of South and Central American toucan-barbets). Besides the eponymous nape, the Golden-naped was overall a brilliant leaf-green with a bright blue crown, forehead and throat (see Photo 6).

  Red, green and blue: tricky colours for feathers

  These are interesting colours for feathers. The bright red features of the partridge and sunbird we had enjoyed before the rain at Kinabalu are due to the presence of pigments called carotenoids – there are many different ones. Curiously, most birds can’t manufacture carotenoids but must obtain them from other sources, such as plants, algae or bacteria, or animals that have already eaten them. This is energy-demanding, extracting them from food and moving them to where they are required in the body. But it gets worse: red carotenoids are hard to come by (flamingos get them from shrimps that have eaten carotenoid-rich algae), so most birds that want them must eat yellow carotenoids then convert them to red, at an even higher energy cost. Presumably the colour is a statement of the owner’s fitness: that he can afford to squander energy simply in order to look gorgeous, and hopefully she’ll be impressed enough to mate with him. In many red species, only the male indulges, but parrots have come up with a red pigment apparently unique to them, called psittacofulvin, which they manufacture themselves. Accordingly, parrot females are as likely as males to be red. The barbet has employed yellow carotenoids, with no conversion, for its lovely nape crescent.

  Blue, however, is another story entirely. Despite the seemingly incontrovertible evidence of our eyes, there are no blue pigments in bird feathers. Instead it’s all a clever use of structure to ensure that only blue light is reflected. Tiny air bubbles are embedded in feather barbules, of just the right size to absorb red and yellow light so they don’t reflect, but blue light does. If you were to take a red feather from a sunbird and a blue one from a barbet and soak them in an appropriate solvent, the red one would fade to white but the blue one would still be blue. On the other hand, if you were to crush the feathers with a hammer or in a vice, the red would be unchanged but the blue one would now be colourless with the bubbles destroyed.

  What about the green of the barbet? Nope, another trick, or rather the same one. Very few birds indeed have green pigments, despite the plethora of green birds, particularly among parrots. Like them, the barbet has yellow pigments across most of its body. Most of these yellow feathers, however (other than the obvious ones on the back of the neck), also have the same blue-reflecting bubbles that those of its face have – and of course blue mixed with yellow gives green (e.g. Hill 2010; Elphick 2014, pp. 79–83).

  Bannerman’s Turaco, like most of the 27 members of its family, all living in sub-Saharan Africa, provides a dramatic exception to the generalisations above about red and green feathers. It is a stunning bird, with metallic green wings slashed with red, a gleaming red nape and peaked crown, yellow bill and a glossy long dark blue tail. The red, however, is not based on carotenoids, and the green is purely due to pigments. Both red turacins and green turacoverdins are copper-based compounds, synthesised in the bird’s body from copper ingested in fruit – it takes around 3 months for a turaco to eat enough fruit (20 kg, containing 20 mg of copper) to make its feathers so green and so red (e.g. Turner 2016). Until recently it was believed that these compounds were unique to turacos, but turacoverdins (or something very similar) are now known from a jacana, a pheasant and the Indonesian Crested Partridge whose colour patterns look remarkably like those of a turaco.

  Bamenda Highlands, Cameroon: vanishing birds

  Bannerman’s Turaco has the misfortune to live only in a seemingly doomed habitat. South-western Cameroon comprises a bulge into Nigeria. The Bamenda Highlands, comprising the sole habitat of this turaco, lie in the north of this bulge. (For some reason they are classified as in ‘north-west Cameroon’.) The Highlands comprise a volcanic plateau between 1000 and 2000 m above sea level, relatively cool and very wet, with a 9-month rainy season. Once they were heavily forested, but overpopulation, repeated burning to clear the forests for subsistence farming and ever-spreading eucalypt plantations for firewood have reduced the rich forests to tiny tendrils of green along streamlines: tendrils that are being gnawed away all the time. Bannerman’s Turaco seems surprisingly capable of surviving in small forest remnants, but this ability is not infinite. The drive into the highlands from the town of Bamenda is profoundly depressing, through a countryside stripped bare of trees – other than eucalypts – even on hills too steep for any useful production. We located the site of a remnant that our guide had birded 2 years earlier, but it was now gone.

  Finally, we moved to Lake Awing: a large natural lake, in the same lake system as Lake Nyos which, in 1986, emitted overnight a massive cloud of volcanically derived carbon dioxide, killing 1700 people. The lake is of considerable cultural significance locally, but is environmentally devastated, surrounded by only a narrow strip of vegetation with a couple of pitifully narrow forested gullies running off it. Here we found the turaco, along with the perky little black and white Banded Wattle-eye, which belongs to a Family of small robust African insect eaters. It too is restricted to the shrinking Bamenda forests. The very smartly turned out gold and black Bannerman’s Weaver and the rusty-coloured Bangwa Forest Warbler fortunately also live in a couple of other sites, but their future is also at best uncertain.

  Normally the opportunity to see spec
ial birds that live only in a small remote part of the world is a privilege that brings pleasure and excitement. This time, however, I left just feeling sad at the thought that these beautiful birds, which have evolved in this place and lived here for hundreds of thousands of years, could well have disappeared from the world before I do. And, of course, with them will go countless plants and small animals whose existence we’re probably not even aware of. Perhaps if more birders were to visit, and if our money could stay in the villages, things might be different, but they’re not. Ecotourism here isn’t doing much harm, but it’s not doing a lot of good either.

  Mindo Valley, Ecuador: a jewel in the crown

  In contrast, Ecuador is a guiding light in how bird-oriented tourism, especially in rainforests, can benefit communities and the environment. Ecuador has a National Avitourism Strategy! It is one of the most extraordinary places for birds (and thus birders!) in the world, with 16% of the world’s bird species in 0.05% of the Earth’s land area. It is perhaps even more striking to put it into the context of the remarkable bird wealth of South America: Ecuador hosts 48% of the continent’s multitudinous species in just 1.6% of its area. Ecuador’s finest jewel is the Mindo Valley and surrounds, part of the Chocó cloud forest bioregion, one of the world’s biodiversity hotspots. It lies not far north-west of Quito on the far side of Pichincha Volcano, which looms over the national capital. Here everything seems geared towards birders – we’re worth a lot to the local economy and, as a result, the mist-swathed forests are fairly well cared for, and infinitely more so than in the Bamenda Highlands.

  Cloud forests

  Cloud forests are generally found in the tropics or nearby, at higher elevations than many rainforests, in situations where, as the name suggests, cloud sits low on or below the canopy for at least part of most days, especially in the afternoon. The moisture in the cloud condenses on leaves and drips constantly to the floor. The exclusion of sunlight for much of the day means both that light levels are low (even by rainforest standards) and that evaporation is reduced, so that everything is always drenched. Ferns, mosses and lichens are abundant and it’s easier to hear birds than to see them. They are there though – cloud forests are very rich and often feature a high proportion of endemic species.

  Paz de las Aves: positive ecotourism news

  A pioneer in the rebirth of the misty Mindo Valley as a must-visit destination for the world’s birders has been a quietly spoken, often-smiling former subsistence farmer called Angel Paz. At the turn of the century, he and his family were of necessity contributing in their small way to the incremental loss of cloud forest to small-scale farming. He was a visionary, however, and when he found a small Andean Cock-of-the-Rock lek (more of that anon) at the bottom of a steep forested gully, he built a track down to it to make it accessible to visitors, encouraged by local bird lodges. In the building process, a large plain bird began to follow him, hopping across the ground to harvest worms thrown up by the excavations. He knew you could eat it, but fortunately did not act on that knowledge. Local bird guides let him know that cocks-of-the-rock were ‘birding silver’ all right – but antpittas (including this Giant Antpitta) were pure gold! Members of the vast South American assemblage of ancient Gondwanan suboscine passerines, they are mythically hard to see in the dense rainforests and cloud forests where they dwell, causing heartache to thousands of birders. Yet here was one hopping boldly in the open …

  Angel is a man of seemingly infinite patience and persistence, and with a remarkable knowledge of the forest and its birds. He knows all their calls and can seemingly carry on conversations with them – they certainly respond to his whistles in kind. With these attributes, over months of work, he found and habituated species after species of antpitta (all otherwise near-impossible for a visiting birder to see) to emerge to feed on wild-gathered forest earthworms. He tried to offer them worms from his compost heap, but they were spurned. I have now seen five species with him (Giant, Ochre-breasted, Yellow-breasted, Chestnut-crowned and Moustached, for the record) but it doesn’t end there.

  A flock of Dark-backed Wood Quail (New World quail, not at all related to Old World ones) comes from the forest to demolish bananas on a forest track. My book says they are encountered ‘only by chance’ – not here though. Tapaculos are another old South American group of uber-skulkers: total heart-breakers. The magnificently named Ocellated Tapaculo is a most striking bird, 22 cm long with white paint splashes on a black canvas, and rusty face and rump – or it would be striking if you could ever see it. It is one of the voices of the cloud forest: a falling whistle that punches through the mist, approaching but never quite arriving. At Paz de las Aves (‘Peace of the Birds’, as well as the play on Angel’s family name) I sat in sheer disbelief as an Ocellated Tapaculo emerged from the forest to accept Angel’s worms, a very few metres from my feet (see Photo 7). None of the birds are dependent on Angel’s worms or fruit offerings, and Angel constantly changes feeding sites to alleviate the risk of predators taking advantage.

  Angel, assisted by his brother Rodrigo and more recently, I have read, his son Venicio, has persisted in the face of initial opposition from his wife (who thought he could have been doing more productive things than feeding his forest chooks) and scorn from neighbours and some family members. No-one now suggests he wasted his time. They have built a nice-looking guest house on site, where people can stay and enjoy local produce, instead of making the pre-dawn drive from Mindo. The family is now comfortably off and have diversified into fruit growing, which has inevitably attracted more birds.

  This is a good news story for the family, for the birds and for visiting birders, but it is a lot more than that. Many people, both locally and further afield, have seen that looking after birds – which, of course, means their habitats – makes good financial sense, as well as the acceptance of a custodial responsibility. If that rainforest down in the gully might be worth money, it makes more sense to leave it alone than to clear it for a few more banana plants. Angel has been invited to train people in private and government reserves to habituate some of their local ‘difficult’ birds in other parts of Ecuador and Colombia; in turn, more people will visit there and spend money locally, and the message spreads.

  Moreover, it’s harder to get people, locals or visitors, to care about a bird they never see. Familiarity can engender a sense of connection and care, which can lead to that essential assumption of the mantle of custodianship.

  Aguas Verdes, northern Peru: more positive ecotourism news

  Further south, in the north of Peru but across on the eastern slopes of the Andes (the opposite side from Angel’s property) in the village of Aguas Verdes, I visited another new venture in rainforest conservation by a farming family. Although I didn’t ask them, I’m sure they haven’t been taught by Angel, because their approach to feeding forest birds is different and they focus on different bird groups. Norbil Becerra is a carpenter who was intending to turn his small family-owned patch of rainforest just outside the village into a coffee plantation. These forests at 1500 m above sea level support a mixture of higher elevation cloud forest species and lower level rainforest birds.

  However, just in time, Norbil visited nearby Huembo Lodge, run by ECOAN, the Asociación Ecosistemas Andinos (Association of Andean Ecosystems): a research and conservation foundation. There he saw his very first hummingbird, which just happened to be the extraordinary Marvellous Spatuletail (and no group of birds has a more delightfully eclectic collection of names than the sublime hummers). Marvellous indeed, but more than that: ‘ridiculously unlikely’ springs to mind. He has a glittering blue crown, an iridescent blue/green/purple throat, green back and white belly with a black line down it. So far, just another hummingbird – which is to say, superb. However, then there’s the tail … The tail feathers are reduced to just two pairs. The central pair are long and spine-like, but the outer pair are immensely long – some three times the length of his body – and crossed over. Most of their length comprises
bare shaft, but they are tipped with purple ‘racquets’ of feather, which wave as he dances on air. I’d be astonished if Norbil hadn’t been smitten by them.

  Back home, he abandoned plans for the coffee plantation and instead applied his trade to building a truly magnificent raised and covered viewing platform looking out into flowering plantings, selected to attract hummingbirds and butterflies. Norbil is clearly a special person and his determination and resilience in the face of pressure are remarkable. It took 7 months for the recalcitrant hummers to find the feeders, but every day he cleaned and refilled the feeders with sugar solution while the pressures grew around him to be ‘sensible’ and plant the coffee crop instead. In the end the hummers came, and now visitors are coming too. I was there in late 2015, about a year after it opened. We arrived in the village in a torrential rainstorm and were invited into a simple two-storey home, with just one open downstairs room (through which a very well-behaved pig wandered en route from the street to the back yard), to drink tea while we waited for the skies to relent. Eventually we were led along the still-streaming unsealed street and along a road out of town for about a kilometre. The white sands underlying the forest drain the water away very efficiently.

  We were rewarded with an enthralling array of hummers, including some restricted range ones that were new to me. The stand-out for me, however, was the amazing Wire-crested Thorntail, with long forked tail and sparkling green throat and forehead feathers that continue upward into a long slender crest (see Photo 8). As it performed its magic in hovering at the pink verbena flowers just in front of us, I was very grateful to Norbil indeed.

  So far it’s a good story, but not unique – many places in the northern Andes put out hummingbird feeders, though mostly they are associated with lodges. However, Norbil then tried something else. In the forest, just off the access track to the hummingbird viewing platform, he built a small raised hide with viewing slots facing the forest floor just a few metres away. A pipe delivers corn from the hide to the field of view provided by the slots. And birds have already learnt to come for the corn, including two species of tinamous (Cinereous and Little) while we were there. I had almost despaired of seeing wild tinamous, most of which lurk in the gloom of the forest floor, yet here they were pottering about right in front of me.