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The Western Amazon
The Western Amazon Basin,
which shares its birds with the Republics of Colombia, Ecuador,
Peru, Brazil and Bolivia, is the most diverse area on the planet for
birds, and indeed, most species of living organism. There are, for
example, up to 300 species of trees and 1000 species of butterfly
per hectare here. Only large mammals are at a lower diversity here
than elsewhere, as the climax Amazonian forest has had so many
millennia to develop that it is in a constant cycle of decay and
re-growth and all nutrients are tied up in the well balanced
ecosystem. As a result there is little protein on the hoof and
large mammals (and traditionally indigenous tribes) occur in small
numbers over large areas. Birds however, have reached the summit of
evolution here, and there is a mind-boggling array of species in
the Bird Continent (South America)with a remarkable number of
species in the Western Amazon.
When the great southern
continent Gondwanaland broke up during the Cretaceous period, the
land mass that is now South America broke off from present-day
Africa and drifted north west until it came to rest against modern
Panama and Costa Rica and formed a permanent land bridge. Before
this land bridge to North America was formed, South America was an
island continent of low relief for about 100 million years. As South
America separated from Africa, it must have carried some primitive
passerines ( perching birds). Modern descendants of this primitive
stock include the manakins (pipridae), the tyrant-flycatchers
(tyrranidae), the cotingas (cotingidae), the ovenbirds
and woodcreepers (furnariidae), the tapaculos (rhinocryptidae)
and the ant birds (thamonophilidae). The other passerine
families that exist in South America are almost certainly of
northern origin; they spread south when the Central American land
bridge was formed. The colonist families of northern origin belong
to the oscines or true songbirds, the southern group of
Gondwanaland origin; the suboscines are deemed more primitive.
Classification is controversial and in constant flux.
There are two major theories
that are offered as explanations of why there are so many birds in
the Western Amazon. the first suggests that during the last Ice Age,
water was locked up in ice sheets and there was less moisture in the
atmosphere available to produce rain, dramatically reducing the
rainfall. Continuous rainforests broke up into separated patches
(refuges), isolated from each other by large stretches of grasslands
or savannah, in which birds evolved over time. When the ice
retreated and rainfall increased, the rainforest once again
flourished and advanced and refuges were reconnected, but the
species, although they had the same common ancestors did not
recognise each other. They had evolved in isolation and become
distinct, thus producing a high number of different bird species.
According to the second
theory, the incredible number of species in the Western Amazon
occurs because it is close to a variety of different ecosystems and
habitat zones and has a complex mosaic of micro-habitats where birds
have found a narrow niche to evolve. The wet and dry savannahs to
the south in Bolivia and Brazil, the towering Andes that border the
Amazon to the west, and the Llanos wet grasslands of Venezuela to
the north have each contributed species that have evolved in these
areas, which have in turn colonised the Amazon rainforest. On first
glance the Amazon looks pretty much the same, although a casual
observer might note the difference between seasonably inundated
varzea forest and the never-flooded tierra firme forest. However
even the most casual of visiting birdwatchers to the Amazon can,
with some care, differentiate between a wide variety of habitats and
micro-habitats that make up a complex mosaic, and the careful
birdwatcher will note that many of the bird species seen have some
very specific habitat preferences. These include the river islands
in large Amazonian rivers, bamboo patches, ox-bow lakes, flooded
varzea forest, transitional floodplain forests, tierra firme
forests, stands of riverside cane, areas of willows along the
rivers, tree-fall gaps, small streams and palm swamps. In these
different areas and forest types different bird species evolved to
produce an avian diversity of astonishing proportions.
Bird Watching Tools in the
Amazon
Binoculars with good light
gathering capabilities and close focusing in the 8x to 10x range are
recommended. A spotting scope with a 25x50x fixed wide angle lens
can be useful for more lethargic species such as trogons (trogonidae)
and puffbirds (bucconidae), and a great asset if you have
access to the rainforest canopy in the form of canopy walkways or
static tree platforms. A telescope is a great help for scanning the
distant tree crowns for cotingas (cotingidae) or observing
feeding aggregations of birds at a distant fruiting tree. A recorder
of some kind and a shotgun microphone can be a useful tool for
enticing difficult species out of their tangled abodes, though
experience and care is needed with this kind of equipment. There are
still comparatively few field guides in South America, although
several projects are underway. There is an excellent Field Guide for
Colombia by Hilty and Brown, and an imminent Field Guide for Ecuador
by Ridgely and Greenfield. Birds of Peru is scheduled to be
published in 2004 and Bolivian and Brazilian guides are in the
pipeline. At the time of writing, however, birders must use a
combination of books for the Amazon and carry a fairly comprehensive
library. Recommended literature includes:
A Guide to the Birds of Colombia.
Stephen L. Hilty and William L. Brown. Princeton University Press
1986.
ISBN 0-691-08372-X
Birds of South America Volume 1.
Robert S. Ridgely and Guy Tudor. University of Texas Press 1989.
ISBN 0-292-70756-8
Birds of South America Volume 2.
Robert S. Ridgely and Guy Tudor. University of Texas Press. 1994.
ISBN 0-19-857218-2
A Field Guide to the Birds of Machu Picchu. Barry Walker and Jon
Fjeldsa. PROFONAMPE 2002.
ISBN 9972-778-05-2
A Field Guide to the Birds of Peru. Clements and Shany. Ibis
Publishing Company 2001.
ISBN 0-934797-18-8.
The Birds of Ecuador.
Paul Greenfield and Robert S. Ridgely. Cornell University Press.
2001
ISBN 0-8014-8722-6
Annotated Checklist of Peruvian Birds.
Theodore A.Parker, Susan Allen Parker and Manuel Plenge. Buteo Books
1982.
ISBN 0-931130-07-7
Many traveling birdwatchers
compile their own customised field guides by scanning or colour
photocopying existing plates including relevant paintings from the
excellent Handbook of the Birds of the World series by del Hoyo ,
Elliot and Sargatal (Lynx Editions, Barcelona) and other bird family
monographs that seem to be appearing in increasing numbers at the
moment.
Whichever aids to birdwatching
you carry, remember that the rainforest is always humid and that
equipment must be waterproofed or be tried and tested in humid
conditions. Equipment failure whilst on a birdwatching trip can be a
very frustrating experience indeed.
How to look for and watch
Birds in the Amazon
The Amazon is perhaps one of
the worlds greatest challenges for a birdwatcher. Ornithologists and
birdwatchers who have lived and worked in the Amazon for long
periods still see new species that have eluded them for many years,
often in an area they have walked countless times before. Every
excursion in the Amazon is a learning experience. Some birds only
sing for a few weeks out of the year and even then many are very,
very hard to see, for example the antpittas (formicaridae)
and the rails and crakes (rallidae). Patience is needed for
many species and, on a first trip to the Amazon, some small
flycatchers (tyrranidae) and antwrens (thamnophilidae)
will initially go unidentified. There are birds everywhere you go;
it is possible to watch birds on an Amazon river cruise, a three-day
visit to a rainforest lodge or even in the gardens of hotels in
large towns or cities. If a trip is being planned specifically for
birdwatching, then a rainforest lodge is the obvious choice as a
base; 500 plus species is the norm at most Western Amazonian
localities. Around lodge clearings, over rivers and along lake
edges, many of the more prominent species such as herons (ardeidae),
parrots (psittacidae), large flycatchers (tyrranidae)
and oropendolas (icteridae) will be seen, but it is in the
forest interior that the more enticing and mysterious birds such as
antbirds (thamnophilidae), ovenbirds (furnaridae) and
manakins (pipridae) will be found. When choosing a lodge,
some factors should be taken into account: is the area protected and
are the large indicator species such as guans (cracidae),
currasows (cracidae) and trumpeters (psophilidae)
still there?. Does the lodge have access to an ox-bow lake and
canoes on the lake? Does it have access to the rainforest canopy in
the form of canopy towers or walkways? Are there stands of bamboo
that trails pass through and are there plenty of trails traversing
different forest types? Is there a nearby macaw lick? If the answer
to all these questions is yes, then you have a good birding lodge.
There are several lodges in the Western Amazon that meet this
criteria but some of the better known include Cristalino River Lodge
(see p.xxx) in Brazil, the La Selva, Sacha and Kapawi Lodges (see
pp.xxx, xxx and xxx) in Ecuador, Amazonia Lodge, Exlornapo lodge,
Manu Wildlife Centre and Tambopata Research Centre (see pp.xxx, xxx,
xxx and xxx) in Peru. Wherever you go, explore all the habitats at
your disposal and make sure you walk through different parts of the
forest on different trails. Try and visit seasonally flooded, terra
firme and transitional floodplain forests, bamboo patches, ox-bow
lakes, river margins and use any tree towers available. Birds in the
Amazon are most active from dawn until about 10am and so early
starts are essential. Take a siesta during the heat of the day and
follow it with some late afternoon birding. Walk slowly and be alert
for bird sounds; learn to recognise the distinctive sounds of an
approaching canopy or under-story flock (see below) and the special
calls made by antbirds at an army ant swarm (see p.xx).
Canopy Flocks and Under-story
Flocks
Many different species in the
Amazon flock together in mixed feeding flocks that roam through the
forest together. There are two main types: canopy flocks and
under-story flocks. They defend a communal territory against
neighbouring rival flocks and, when the two kinds of flock join
together, there can be as many as 80 species of birds together,
usually a pair of each species. Each flock has a leader, the
cohesive element in the group, which is always of the same species;
in the Western Amazon canopy flocks are led by fulvous
shrike-tanagers (lanio fulva) in the north and white-winged
shrike-tanagers (lanio versicolor) in the south. Under-story
flocks are led by cinereous antshrikes (thamnomanes caesius)
in the north and bluish-slate antshrikes (thamnomanes
schistogynus) in the south. The advantage of being part of a
flock is that there are more pairs of eyes to look for predators
such as forest-falcons (micrastur spp.) and all species in
the flock have distinctive alarm calls that other flock members
recognise as warning signals. There is little competition for food
as each species looks for prey in a different place; antwrens (thamnophilidae)
glean the undersides of leaves, or investigate dead leaf
clusters, woodcreepers (dendrocolaptidae) probe into bark,
foliage-gleaners (furnariidae) rummage in dead palm leaves,
tanagers (thraupidae) search for small fruits, trogons (trogonidae)
for large anthropods and flycatchers (tyrranidae) seek flies
in the shady under-story, and so on. Learning to recognise the calls
of the flock leaders will help greatly when trying to locate these
species-rich flocksin the Amazon, birds of a feather do not
necessarily flock together.
Some of the Birds:
Manakins (Pipridae)
Some of the most enigmatic and
interesting species in the world live in the Amazon; perhaps the
most enigmatic of all the Amazonian species are the manakins (pipridae),
similar to tits (paridae) or chicakadees (paridae),
compact, stocky and energetic. They can be difficult to see unless
you find a display area. Most hover-glean for small fruits and many
have modified flight feathers that make whirring and snapping
sounds. They live mainly in the forest interior, sometimes coming to
the forest edge for fruits. They have elaborate courtship displays
that vary from species to species, where two or more brightly
coloured males display at courtship arenas known as leks in
ornithological terms. Females are shades of olive. To illustrate the
complexity, lets take a look at the flamboyant display of the
blue-backed manakin (Chiroxphia pareola). Two males perch on
a gently sloping branch about a metre off the ground, giving a loud
characteristic song throughout the day. When a female arrives,
attracted by the singing, the males go into full display, jumping
over each other, cartwheeling and sidling on the branch and calling
more and more rapidly until they suddenly stop dead still and one
bird gives a loud swee..ee..eek. After that only one male
continues to display, crouching and singing softly and periodically
making short, slow circular flights with rapidly fluttering wings.
This may culminate in copulation. Manakin leks can be found
scattered around the forest and several gaudy species can be
encountered, including red-headed (pipra rubrocapilla),
round-tailed (pipra chloromeros), wire-tailed (pipra
filicauda), blue-crowned (pipra pipra), band-tailed (pipra
fgascicauda), golden-headed (pipra erythrocephala) and
fiery-capped manakins (machaeropterus
pyrocephalus).
Cotingas (Cotingidae)
Another brilliantly plumaged
family that, like the manakins (pipridae), is strictly
American, is the cotinga family (cotingidae). Mainly found in
the immense Amazonian rainforests, many species are showy, with deep
reds and shades of mauve, purple and blue, like the lustrous blue
cotingas (cotinga spp.), being common. In the foothills of
the Andes, variations on green are more common and in the bellbirds
(procnia spp.), almost totally white plumage occurs in two of
the species. Cotingas (cotingidae) eat fruit and mainly live
high in the rainforest canopy; they include the dazzling blue (cotinga
nattererii) spangled (cotinga cayana) , plum-throated (cotinga
maynana) and purple-breasted cotingas (cotinga cotinga),
the fruiteaters (pipreola spp.) of the foothills including
the gaudy fiery-throated (pipreola chlorolepidota) and
scarlet-breasted (pipreola frontalis), the strange looking
amazonian umbrellabird (cephalopterus ornatus) with its crown
of feathers and long bare wattle, the striking andean
cock-of-the-rock (rupicola peruviana) of the hill country
that croaks and dances daily in a raucous display at favourite
dancing grounds and the jay-like black-necked red cotinga (phoenicircus
nigricollis). These are real prizes to be found and enjoyed by
visitors and many can be seen with ease if you have access to a tree
tower.
Toucans, Aracaris and
Toucanets (Ramphastidae).
Toucans and their allies, the
aracaris and toucanets (ramphastidae) are often found feeding
in the same fruiting trees that cotingas (cotingidae) attend.
They are South American counterparts to the hornbills (tockus spp.)
of the Old World and are readily recognised by their large colourful
bills and the astounding ability to lay their tail flat over their
backs. Raucous and brightly coloured, this family is a conspicuous
member of the rainforest bird community. They nest in holes in trees
and roam the forest in groups searching for fruit, supplemented with
insects and not beyond raiding nests of other birds for nestlings
and eggs. Aracaris (pteroglossus), the smaller members of the
toucan family, include chestnut-eared (pteroglossus castanotis)
- perhaps the most familiar, ivory-billed (pteroglossus
flavirostris), curl-crested (pteroglossus beauharnaesii)
- with its curiously curled, plastic-like crown feathers,
many-banded (pteroglossus pluricinctus and lettered (pteroglossus
inscriptus) - named for the strange scribble-like markings along
the cutting edge of the bill. Among the toucanets (aulacorynchus
spp.) is the emerald (aulacorynchus prassinus) and the
croaking golden-collared (selenidera reinwardtii). The large
toucans of the Amazon that are a characteristic sound of the late
afternoons and evenings in the forest include the yellow-ridged (ramphastos
culminatus) and Cuviers toucans (ramphastos cuvieri)
that sit up in bare trees and yelp in unison as the sun sets over
the rainforest canopy.
Tanagers (Thrapidae) and
Hummingbirds (Trochilidae)
The treetops are also the home
of another typically American family, the tanagers (thraupidae),
whose colourful beauty has led many people to paint and study them.
They are important distributors of seeds of rainforest trees, shrubs
and vines: To stand in bright morning sunshine before a tree laden
with ripening berries is one of the great delights of bird-watching
in tropical America. Among the constantly changing throng of birds
that gather for the feast are, brisk, tiny manakins, flycatchers
large and small, plainly clad thrushes and vireos, wood-warblers and
woodpeckers. But, nearly always, the tanager family provides the
greatest number of species and individuals and most of the colour,
said renowned sage Alexander Skutch. Tanagers (thraupinae)
have perhaps reached their greatest diversity and gaudiness in the
misty cloud forests and foothills of the Andes, but they are well
represented in the Amazon. They draw attention to themselves with
distinct foraging calls as they move through the rainforest canopy,
often accompanying toucans (ramphastidae), aracaris (pteroglossus
spp.) and cotingas (cotingida spp.) in mixed canopy
feeding flocks or feeding aggregations at fruiting trees. The
honeycreepers (cyanerpes spp) and dacnis (dacnis spp.)
are specialised tanagers that are designed to extract nectar from
flowers; their bills are thinner and longer than those of true
tanagers and are well suited for probing the corolla of flowers and
extracting nectar with a fringed tongue. They are brightly coloured
little birds, the males being strikingly black and purple, deep
blue, turquoise, green and bright yellow, although the females are
duller.
Often the honeycreepers (cyanerpes
spp.) and dacnis (dacnis spp) will be found in the same
flowering trees as hummingbirds (trochilidae). Brightly
coloured hummingbirds tend to be found in the canopy and can be
difficult to see, whereas the under-story is dominated by the drab
hermit hummingbirds (phaethornis spp). Euphonias (euphonia
spp.), brightly coloured and musical small tanagers, and true
tanagers pluck berries and supplement their diet with insects whilst
perched. At a fruiting or flowering tree in the rainforests of the
Manu Biosphere Reserve, the following might be seen in the same tree
at the same time: green and gold tanager (tangara schrankii),
masked tanager (tangara nigrocincta), red-billed pied tanager
(lamprospiza melanoleuca), guira tanager (hemithraupis
guira), turquoise tanager (tangara mexicana), masked
crimson-tanager (ramphocelus nigrogularis), white-winged
shrike tanager (lanio versicolor), yellow-crested tanager (tachyphonus
rifiventer), white-shouldered tanager (tachyphonus luctosus),
yellow-backed tanager (hemithraupis flavicolis), green (chlorophanes
spiza) and purple honeycreepers (cyanerpes caeruleus),
blue (dacnis cayana), black-faced (dacnis lineata) and
yellow-bellied dacnis (dacnis flaviventer) , orange-bellied (euphonia
xanthogaster), thick-billed (euphonia laniirostris),
white-vented (euphonia minuta) and rufous-bellied euphonies (euphonia
rufiventris)a vision to whet anyones appetite for Amazonian
birding.
Understory Birds : Tinamous (Tinamidae),
Trumpeters(Psophiidae) and Ovenbirds (Furariidae)
Not all birds are treetop
dwellers and brightly coloured, and it is in the shady under-story
and close to the trunks of the giant rainforest trees that the more
sombrely coloured bird families find their home. The rainforest
floor provides a great food source in the form of fallen fruits or
insects and grubs hidden amongst the leaf-litter. Foraging on the
forest floor, however, is a risky business because of predators and
most forest floor species are extremely wary; dedication and stealth
from the bird-watcher are required here. Often currasows and guans (cracidae)
will venture onto the ground from their leafy sub-canopy to take
advantage of fallen fruits and can startle as they flush noisily
into the cover of trees. The tinamous (tinamiidae) are more
often heard than seen; the haunting call of the great (tinamuis
major) or bartletts tinamou (crypturellus bartletti) on a
moonlit night is one of the most beautiful sounds on earth.
Undulated (crypturellus undulates) and cinereous tinamous (crypturellus
cinereus) often give their whistled calls on the hottest of
tropical afternoons. Tinamous (tinamiidae) are sought after
by many experienced Amazonian bird-watchers and there is no easy way
to find them; scurrying down a jungle trail may give a glimpse, or
you may be lucky and find a pair quietly feeding underneath a
fruiting fig tree. Although their calls betray their presence,
sightings are all too few. If you are lucky, a flushed tinamou may
reveal a nest of brightly coloured porcelain textured eggs. Male
tinamous incubate the eggs and look after the young, and the females
may lay eggs in nests of different males. The tinamous (tinamiidae)
share the forest floor with wood-quails (phasianidae), whose
evensong rings through the forest at dusk and after dark, and the
strange trumpeters (psophiidae). Trumpeters (psophiidae)
are shy and one of the first birds to disappear if there is too much
human impact. They are related to cranes and rails and have a well
developed social behaviour, patrolling their territory in family
groups, keeping in contact with low purring and whooping calls which
escalate into the full song of guttural humming notes if they sense
danger. They sing at full moon also, and eat insects, fallen fruits,
lizards and snakes. Many Amazonian tribes keep trumpeters as pets in
their villages as they are good watchdogs, raising the alarm if an
intruder or snake is in the vicinity.
The ovenbirds (furnariidae)
are denizens of the shady forest as well, seldom coming out into
full view. They are shades of brown and chestnut and can present
identification problems until their songs and behaviour are learned.
The foliage-gleaners (automolus and philydor) and leaf-tossers
(sclerurus) are common members of mixed feeding flocks; the
automolus foliage-gleaners keep low in thick undergrowth,
while the philydor group are more conspicuous and forage
higher. They specialise in rummaging in dead leaf clusters and
investigating palm leaves or throwing aside leaf litter in search of
insects. Some are bamboo specialists, always found within large
bamboo stands, such as the peruvian recurvebill (simoxenops
ucayalae), with its strangely upturned bill used for cracking
off pieces of bamboo to search for grubs and its nanny-goat like
call, and the inconspicuous brown-rumped foliage-gleaner (automolus
melanopezus). Unless you look for these birds in bamboo you will
not see them, a good example of how important it is to examine the
available literature about what a bird does and where it lives in
the forest in order to find it, rather than just looking at a
picture. Other ovenbirds (furnariidae) include the spinetails,
woodhaunters and the horneros who build mud oven-like nests on
exposed branches along the ox-bow lakes (horno is Spanish for oven).
One of the largest and more
complicated groups, now placed in the ovenbird family, is the
woodcreeper (dendrocolpatidae) sub-family. Woodcreepers (dendrocolpatidae)
climb trunks and large tree limbs in the manner of a woodpecker (picidae)
(no relation). They are drab brown and olive with varying amounts of
streaks and spotting and identification is difficult. One way to
deal with this group is by learning their songs and calls but even
this is complex as many species imitate each others calls and each
species gives a variety of calls, dawn songs, dusk songs, etc. The
common buff-throated woodcreeper (xiphorhynchus guttatus)
gives a bewildering variety of calls and it is worthwhile learning
this well in order to be able to compare all other woodcreeper
species to it. Some woodcreepers (dendrocolpatidae) are most
easily encountered at army ant swarms, for example the plain-brown (dendrocincla
fulginosa), strong-billed (xiphocolaptes promeropithyncus),
barred (dendrocolaptes certhia) and bar-bellied woodcreeepers
(hylexetastes stresmanni). One species, the white-chinned
woodcreeper (dendrocincla merula), is an obligate army ant
follower and is never found away from such swarms.
Army Ant Followers:
Obligate army ant followers
are birds that, as part of their survival strategy in the forest,
are always present at army ant swarms. They dont eat the
carnivorous ants, which are full of formic acid and unpalatable, but
prey on the fleeing grasshoppers, spiders, other insects and even
frogs, that are trying to escape the marauding hoards of ants that
carpet the forest floor. This is one of the great wildlife
experiences of the Amazon and to watch an ant swarm in full swing
with attendant birds is a wonderful bird-watching spectacle. Spiders
and grasshoppers run and jump in panic trying to escape the ants
only to be snapped up by a waiting attendant bird. Many of the
species that attend the swarm are of the antbird (thamnophillidae)
family, which, although consisting mostly of non ant-following
species, derives its name from a few species of professional army
ant followers, like the white-throated (gymnopithys salvini)
and lunulated antbirds (gymnopithys lunulata) and the
bare-eyes (phlegopsis spp.) - spectacular members of the
antbird family and a real prize.
Antshrikes, Antbirds, Antwrens,
Gnateaters (Thamnophiidae), Anthrushes and Antpittas Formicariidae).
Some species are not obligate
army ant followers but attend periodically at swarms; these include
the hairy-crested (rhegmathorina melanosticta), sooty (mymeciza
fortis), plumbeous (myrmeciza hyperythra) and
white-browed antbirds (myrmoborus leucophys).. The majority
of the antbird (thamnophiliidae) family are to be found
occupying various niches in the forest away from ant swarms. They
vary in size from small to medium sized birds and up to 30 or 40
species may be found at the same locality in the Amazon. They
consist of several groups: antshrikes, antbirds, antwrens,
gnateaters, anthrushes and antpittas. The latter two are terrestrial
and sometimes considered a separate familythe ground-antbirds (formicariidae).
They are inconspicuous and shy and often only betray their presence
with far carrying calls and songs. Antpittas (formicariidae)
are the stuff of legend and their names often reflect thatfor
example, the Elusive Antpitta! (grallaria eludens) The
antwrens, antshrikes and antbirds (thamnophiliidae) are more
easily seen and occupy many habitats and levels in the forest, often
accompanying mixed species flocks. Most show great sexual dimorphism
with males being shades of grey and black and females exhibiting
shades of brown, buff and rufous. They feed by gleaning foliage for
insects at all levels from the ground to the sub-canopy. Some are
restricted to bamboo, such as the ornate (myrmotherula ornate)
and Ihrings antwrens (myrmotherula iheringi), some to lake
edges and swamps such as the Amazonian streaked antwren (myrmotherula
surinamensis), the band-tailed antbird (hypocnemoides
maculicauda) and the silvered antbird (sclateria naevia).
Some never descend from the canopy, like the chestnut-winged (terenura
humeralis) and sclaters antwrens (myrmotherula sclateri),
and some prefer mid-levels and are much more likely to be seen, such
as the white-browed (myrmoborus leucophrys) and black-faced
antbirds (myrmoborus myotherinus), the dusky-throated
antshrike (thamnomanes ardesiaca) and the white-flanked (myrmotherula
axillaries) and long-winged antwrens (myrmotherula
longipennis).
Predators: Falcons, Kites and
Eagles
Antbirds (thamnophiliidae)
have to deal with predators in the form of forest-falcons (micrastur
spp.) that lurk in vine tangles following mixed feeding flocks,
just waiting for a chance to dash out and snatch an unwary bird.
Birds of prey in general, as in other parts of the world, have
occupied virtually every rainforest niche. Plumbeous (ictinia
plumbea) and swallow-tailed kites (elanoides forficatus)
hawk above the rainforest canopy for large flying insects, sharing
this aerial enviroment with a variety of swifts (apodidae spp.).
Double-toothed kites (harpagus bidentatus) follow monkeys,
snatching large tasty insects flushed as the primates move through
the forest. Accipiters like bicolored (accipiter bicolour)and
tiny hawks (accipiter superciliosus) dash through undergrowth
also after smaller birds. Snail kites (rostrhamus sociabilis)
and black-collared hawks (busarellus nigricolis) specialise
in lake edge habitats. Ornate (spizaetus ornatus), black (spizaetus
tyrranus) and black and white (spizastur melanoleucus)
hawk eagles share the canopy with short-tailed (buteo brachyurus)
and slate-coloured hawks (leucopternis schistacea). The most
powerful eagle in the world lives here; the magnificent harpy eagle
(harpia harpyja), over-shadowing the closely related crested
eagle (morphnus guianensis) by only a centimeter or two.
These eagles reach up to 40 inches in length and they feed on large
arboreal mammals such as monkeys (cebidae) and sloths (bradypodidae).
Despite their size, the harpy ((harpia harpyja) and crested
eagles ((morphnus guianensis) are difficult to see as they
seldom soar and usually keep within the tree crowns and usually only
show themselves when crossing rivers or clearings.
Nocturnal Predators
At dusk there is a changeover.
As diurnal mammals go to sleep and nocturnal mammals awake, so do
the predators that have evolved to feed on them; hawks, eagles and
falcons (accipitridae) are replaced by owls (strigidae),
and the nocturnal insect population is preyed upon by nighthawks,
nightjars (caprimulgidae) and the strange potoos (nyctibiidae).
Spectacled owls (pulsatrix perspicillata) give their long
reverberating calls, screech-owls (otus spp.) hoot around
rainforest lodge clearings, the magnificent crested owl (lophostrix
cristata) replaces the eagles hunting in the sub-canopy and the
tiny Amazonian pygmy owl (glaucidium hardyi) trills in the
canopy between insect-hunting bouts. The cosmopolitan nightjars and
nighthawks (caprimulgidae) occupy various niches, searching
for insects and moths in the canopy, along rivers and in the
under-story. Potoos (nyctibiidae), South Americas answer to
the frogmouths (batrachostomus spp.), sit motionless all day
mimicking dead tree limbs and they become active at dusk giving
haunting cries as the sun sets or at full moon, and silently float
through the forest catching moths during the night.
Along the Rivers and Lakes
Not all Amazonian birds
inhabit the forest; many are best looked for and found along
tropical Amazonian rivers and ox-bow lakes. As the mighty Amazonian
rivers drop in level during the dry season between June and
September, many birds take advantage of the exposed sandy beaches to
raise their young. On little disturbed rivers (unfortunately harder
and harder to find), orinoco geese (neochen jubata), muscovy
ducks (cairina moschata), pied lapwings (vanellus cayanus),
collared plovers (charadrius collaris) and sand-coloured
nighthawks (chordeiles rupestris) nest. Two freshwater terns,
the dainty yellow-billed (sterna superciliaris) and the more
powerful large-billed terns (phaetusa simplex), share the
fish according to size and take advantage of the beaches for
breeding along with the black skimmers (rynchops niger).
Hidden just a few metres inside the forest are the ox-bow lakes
formed as the rivers meander and finally cut through the narrow neck
of an exaggerated loop, leaving the old river bed as a lake. The
life cycle of these lakesfrom being newly formed to returning to
forest after a lengthy process of colonisation by aquatic vegetation
and colonial plants such as Cecropia spp followed by Ficus
spp.,can take several hundred years. These lakes create a
distinct habitat that is used by the rivernesting terns (laridae)
and ducks (anatidae)). Herons (ardeidae) are a great
feature of these ox-bow lakes, and also inhabit the rivers. The more
conspicuous species, such as the snowy (egretta thula) and
great egrets (egretta alba), the white-necked herons (ardea
cocoi) and roseate spoonbills (ajaia ajaia) are easily
seen in numbers along the rivers, as well as American wood-storks (mycteria
Americana) and the giant improbable jabiru (jabiru mycteria),
South Americas equivalent of the African maribou (leptoptilus
crumeniferos). The shy and unobtrusive species are, however,
mostly found under the overhanging vegetation, along the shady
shores of the ox-bow lakes. The much sought after agami heron (agamia
agami) is here, alongside striated (butorides striatus)
and boat-billed herons (cochlaerius cochlaerius). If you are
lucky you may see a pinnated (botaurus pinnatus) or
stripe-backed bittern (ixobrychus involucris). Green ibis (mesembrinibis
cayennensis) and anhingas (anhinga anhinga) also find a
home here, the latter often swimming with just its elongated neck
showing above the water and the body submerged, giving rise to one
of its other namessnake-bird. One strange ox-bow lake inhabitant
is the hoatzin (opisthocomus hoazin), a prehistoric-looking
turkey-like bird that grunts and hisses in the lakeside vegetation.
The hoatzin (opisthocomus hoazin) is a member of the cuckoo
family and, despite its looks, not prehistoric at all. It nests on
flimsy stick platforms in bushes above the water and the nestlings
have a strange evolutionary development, a hook on the bend of the
wing. This enables the young birds to clamber back up to the nest
after they have ejected into the water to escape the attentions of a
predatora neat defence mechanism and a good survival strategy.
Flycatchers
Also here on these tranquil
lakes and rivers are conspicuous flycatchers, and tropical kingbirds
(tyrannusmelancholicus), social (myiozetetes similes)
and gray-capped (myuozetetes granadensis) flycatchers, great
(pitangus sulphuratus) and lesser kiskadees (pitangus
lictor) area fairly common sight. The tyrant-flycatcher (tyrannidae)
group is an enormous family, which ranges from small tody-tyrants (todirostrum)
and tody-flycatchers (hemmitriccus), canopy elaenias (elaenia
and myiopagis spp.) and tyrannulets to the large noisy attilas (Attila
spp.) and mourners . Not all are found along the lakes and
rivers; indeed, the vast majority are to be found in the forest
interior, inhabiting all niches and habitats from the canopy to the
ground. Many specialize in bamboo thickets, such as the dusky-tailed
(ramphotrigon fuscicauda) and large-headed flatbills (ramphotrigon
megacephala), the white-cheeked tody-flycatcher (poecilotriccus
albifacies) and the flammulated bamboo-tyrant (hemmitriccus
flammulatus). Others, like the sulphury flycatcher (tyrannopsis
sulphurea) and citron-bellied Attila (Attila citriniventris),
like stands of palms. Many are canopy dwellers and until their calls
and songs are known, they can be almost impossible to see and
identify.
Parrot Family: Parrots,
Parakeets, Parrotlets and Macaws
The Parrots, Parakeets,
Parrotlets and particularly the Macaws (psittacidae) are as
much a part of the Amazon as are Giant Otters (pteranura
basilensis) and Brazil Nut Trees. Wherever you arecanoeing on
an oxbow lake, taking a leisurely river trip or walking through the
rainforest on a sunny afternoonthe constant chatter of parakeets or
the explosive cries of the macaws are a constant companion. Noisy,
gregarious and gaudy, they are everywhere, and include the tiny
dusky-billed (forpus sclateri), Amazonian (nanopsittaca
dachilli) and scarlet-shouldered parrotlets (touit huetti),
the great flocks of white-eyed (aratinga leucopthalmus),
dusky-headed (aratinga weddelli), cobalt-winged (brotogeris
cyanoptera) and tui (brotogeris sanctithomae) parakeets
flying over the rivers in the evening, the big amazon parrots such
as mealy (amazonas farinose), yellow-headed (amazonas
ochrocephala) and Orange-winged Parrots (amazonas amazonica)
to the smaller short-tailed parrots (graydidascalus
brachyurus) blue-headed (pionus menstuus) and
orange-cheeked parrots (pionopsitta barrabandi) and the
great, noisy and colourful scarlet (ara macao, red and green
(ara chloroptera) and blue and yellow (ara ararauna )macaws.
The big macaws, and their smaller relativeschestnut-fronted macaws
(ara severa) and red-bellied macaws (ara manilata) in
the palm swampsare an integral part of the makeup of the Amazon and
no trip to the Amazon rainforest would be complete without a visit
to one of the great wildlife spectacles: a macaw lick. There are
several macaw licks close to lodges in the Western Amazon: macaws,
parakeets and parrots all attend these clay river banks. Great
numbers gather at these traditional sites to eat clay, which is
essential to their digestion, acting as a neutralising agent for the
mild poisons that exist in the limited variety of fruits they are
obliged to eat during the dry season from July to September. Its
rather like a human taking kaolin for an upset stomach. Just after
dawn, great numbers of blue-headed (pionis menstruus), mealy
(amazonas farinose) and yellow-headed (amazonas
ochrocephala) parrots, with a sprinkling of the gaudy
orange-cheeked parrots (pionopsitta barrabandi), gather at
the lick. Often dusky-cheeked (aratinga weddelli) and
cobalt-winged parakeets (brotogeris cyanoptera) are present
too, adding to the astonishing clamour. After they have had there
fill, and as if to an invisible signal, they fly off the lick in a
crescendo of noise and colour, circling briefly before heading into
the forest, leaving an eerie silence in their wake. It is now time
for the macaws to gather. In pairs and family groups of three and
four, the gaudy macaws fly in, calling in a subdued manner, and
begin to gather in the trees above the lick. As the numbers grow
they seem to gain in confidence and drop lower and lower until they
are just above the lick. Suddenly, one brave soul drops onto the
clay bank, signalling for all and sundry to join the party. For
perhaps an hour the great colourful macaws caw and squabble on the
bank as they get their bi-daily intake of clay. Suddenly, as with
the parrots that preceded them, they leave the lick in a swirling
multicoloured mass and break up into family groups and pairs to get
on with their daily routine in the forest. The lick is then deserted
and silent until the next day. A sight to see indeed.
Bird watching in the Western Amazon holds
something for all and here we have mentioned only a few of the
families and species to be found. There are plenty of easy-to-see
and interesting birds for less intense observers and difficult
identification problems to keep in-depth observers busy for years.
There are still mysteries to be solved and too many questions to be
answered in a single lifetime. You will find yourself asking, why do
they fly in large numbers over the river at dusk? What does that
bird feed on? Why does it do that? Where does it nest and what does
its nest look like? One thing is for sure, the Amazon will never
lose its attraction and magnetism for birdwatchers, bird lovers and
ornithologists alike.
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