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Fruit and nectar feedersCotingas
• Cotingas (Passeriformes) are among the most ‘glamorous’ of Neotropical birds
• Bellbirds, umbrellabirds, cocks-of-the-rock, pihas, fruiteaters, fruit-crows, and purpletufts
• All are rainforest birds, some continuing up into the cloud forests and all are ‘extreme’ fruit specialists
Fruit and nectar feedersCotingas
• Cotingas have wide, flattened bills, accomdating round fruits
• Poor seed predator=good disperser
• Heavy fruit diet also results in very slow incubation time for young
Fruit and nectar feedersCotingas
• Umbrellabirds and cocks-of-the-rock, are large and have ornate plumage on their heads
Fruit and nectar feedersCotingas
• Pihas (captain of the forest) and fruiteaters are smaller and drab
• Sexually, range from monogamous (frequently lacking dimorphism) to polygynous, some with large leks
Fruit and nectar feedersCotingas
• Voice: bellbirds are known for the loud, bell-like notes, pihas for loud scream
• Plumage: cotingas have shiny metallic plumage and cock-of-the-rock and umbrellabirds for the dramatic head feathers
Fruit and nectar feedersCotingas
Fruit and nectar feedersCotingas
Fruit and nectar feedersManakins
• 53sp of manakins (Passeriformes) which are small, chunky, frugivores inhabiting lowland forests
• Phylogenetically close to cotingas and tyrant flycathers (several genera may not be true manakins)
• Males very colorful, females usually drab
Fruit and nectar feedersManakins
• Manakins have short tails, rounded wings, and a short but wide bill with a hooked tip
• Pluck fruit on the wing
• Occasionally eat arthropods
Fruit and nectar feedersManakins
• Famous for the elaborate courtship displays
• Many are ‘arena’ birds and display in large leks, others have cooperative displays
• Females build nests, incubate and feed small clutch (one or two)
Fruit and nectar feedersManakins
• VIDEO
Suboscines
• Of the 3,700+ sp of Neotropical birds, approximately 1,000 are ‘suboscines’
• There are only 50 other suboscines worldwide
• They are part of perching birds (Passeriformes) of which, most are oscines (songbirds: complex musculature of the syrinx)
Suboscines
• There are two major radiations– Tyrant flycatchers, manakins, and
contingas– Woodcreepers, ovenbirds, true antbirds,
ground antbirds, gnateaters, and tapaculos
• Not clear as to why this group is so successful in the Neotropics; may be historical
SuboscinesInsect-Arthropod Feeders
• Many groups utilize insects and arthropods as the primary portion of their diet
• They are extremely species-rich– Ovenbirds (218 sp)– Antbirds and Ground Antbirds (250 sp)– Woodcreepers (45 sp)– Tyrant flycathers (393 sp)
• All are Neotropical sp (a few tyrants mig)
SuboscinesInsect-Arthropod Feeders
• Tyrannids, ovenbirds, and antbirds each represent adaptive radiations, probably assisted by the specialization encouraged by dietary competition
• Insect catching birds are going to develop a particular pattern of feeding and its size, behavior, and bill shape become very refined on a particular size range and type of prey
SuboscinesInsect-Arthropod Feeders
• When you add the high inter-specific competition in the tropics, the diffuse competition encourages an individual to stay focused on its optimal niche
SuboscinesInsect-Arthropod Feeders
• Insectivorous diets are frequently categorized by how they forage– Flycatching (tyrants, puffbirds, nunbirds)– Bark probing (woodpeckers &
woodcreepers)– Foliage gleaning (ovenbirds & many
antbirds)– Ant following (some antbirds, other sp)
SuboscinesInsect-Arthropod Feeders
(flycatching)• Puffbirds and
Nunbirds (Piciformes) consist of 32 endemic Neotropical sp
• Found throughout Amazon basin
• All excavate, many in termite mounds
SuboscinesInsect-Arthropod Feeders
(flycatching)• Puffbirds look
puffy and most are brown (some black and white)
• Cryptic plumage, stationary feeding and understory location make them rarely seen
SuboscinesInsect-Arthropod Feeders (bark
feeders)• Woodpeckers (family Picidae,
Piciformes) both drill and probe bark, extracting mostly larvae using their long, extrusible, barbed tongue
• Occur worldwide (not Australia)• Vary in size..ivory-billed (35cm) to
piculets (9cm); Imperial (60cm) of western Mexico probably extinct
SuboscinesInsect-Arthropod Feeders (bark
feeders)• Climb vertically using adapted tail as
a third prop• Toes zygodactyl to help
grasp
SuboscinesInsect-Arthropod Feeders (bark
feeders)• Range in color from black and red
crest, to greenish olive, to soft browns and chestnut
SuboscinesInsect-Arthropod Feeders (bark
feeders)• Others are ‘ladderbacks’ of B&W
SuboscinesInsect-Arthropod Feeders (bark
feeders)• Woodpeckers are
primary excavators, but are frequently usurped by larger species (e.g. collared aracaris)
SuboscinesInsect-Arthropod Feeders (bark
feeders)• Woodcreepers look like woodpeckers,
but are unrelated (family Dendrocolaptidae, Passeriformes), most closely related to ovenbirds
• Excellent example of evolutionary convergence
• Feed by probing bark crevices & epiphytes
• May join army ant mixed-species flocks
SuboscinesInsect-Arthropod Feeders (bark
feeders)• Like furnids,
woodcreepers are soft shades of brown and rufous (with some whitish or yellowish streaking)
SuboscinesInsect-Arthropod Feeders (bark
feeders)• Its overall size, bill size and shape,
and streaking pattern usually separate one species from another
• Range in size from 15cm to 36cm• Found in wet to dry forests
SuboscinesInsect-Arthropod Feeders (bark
feeders)• Personal favorite;
scythebills• Feed in bromeliads
and other epiphytes
SuboscinesInsect-Arthropod Feeders
(foliage gleaners)• Ovenbirds (Furnariidae;
Passeriformes) are ‘LBB’ of the tropicsw
• All are brown, tan, or gray with very little subtle differences occurring
SuboscinesInsect-Arthropod Feeders
(foliage gleaners)• Name is derived from ‘oven’ like
dome-shaped nests (although not all do this)
• Occur in lowland forest, cloud forest, dry forests, as well as the pampas, puna and paramo
SuboscinesInsect-Arthropod Feeders (ant
followers)• Antbirds (Formicariidae;
Passeriformes) include antbirds, antshrikes, antwrens, antvireos, antthrushes, & antpittas
• They follow…ants• The degree to which they follow varies
from never to ‘professionally’• Antbirds are more colorful than the
ovenbirds with many having sexually dimorphic species
SuboscinesInsect-Arthropod Feeders (ant
followers)• Males are frequently
boldly barred BW• Many have chestnut
or brown as well• Many have blue or
red skin around eye, some have a red eye
SuboscinesInsect-Arthropod Feeders (ant
followers)• Most antbirds are foliage gleaners,
picking and snatching insects from the foliage, with some catching on the wing
• They typically form mixed species flocks with other birds and divide the area vertically amongst themselves
• Certain species tend to dominate the central positions
SuboscinesInsect-Arthropod Feeders (ant
followers)• How would you describe the
relationship amongst the members of these flocks?
• There are 28 sp of ‘professional’ ant-following birds
• In addition, there are many species which opportunistically join flocks as they pass through their territories
• Some butterflies join the flock. Why?
SuboscinesInsect-Arthropod Feeders (ant
followers)• In central America, the spotted
antbird, bicolored antbird and black-faced antthrush are dominant players
SuboscinesInsect-Arthropod Feeders (ant
followers)• Some of the part-timers following ant
swarms are woodcreepers, ovenbirds, motmots, some tanagers, and a surprising number of migrants
• Only when breeding to they cease to follow ants (although they quickly follow any ants that come through their territory)
SuboscinesInsect-Arthropod Feeders (ant
followers)• Antbirds mate for life
and both sexes help building and raising young
• At least one species, ocellated antbird, forms clans with subsequent male generations returning and defending territory
Birds of Prey
• Not surprisingly, birds of prey are also very abundant in the tropics
• Many species occupy open areas as they are easy to soar and search
• However, plenty of species still utilize the resources of the forests (e.g. forest falcons)
Birds of PreyKites
• 11 sp of kites live in the Neotropics eating small animals such as mice, birds, lizards and arthropods
• Generally have sharp, hooked bills
• Often in savannas
Birds of PreyKites
• Notable species include the snail kite, swallow-tailed kite, pearl kite (at 9” one of the smallest)
Birds of PreyHawks, Falcons, & Caracaras
• 40 sp of hawks are found in the Neotropics
• Crane Hawk is found in wet savannas to mangroves and probes epiphytes and branches for amphibians and reptiles
Birds of PreyHawks, Falcons, & Caracaras
• Savanna Hawk which is often seen walking
• In contrast, the white hawk often is seen soaring over forests
• Other soarers include the black hawk and great black hawk
Birds of PreyHawks, Falcons, & Caracaras
• Black-collared hawk feeds on fish, found near marshes
• Distinctive shape (wide wings, short tail)
Birds of PreyHawks, Falcons, & Caracaras
• Roadside hawk is among the most commonly seen BoP in the tropics as it frequently is perched along roads
• Highly variable plumage (13 races)
Birds of PreyHawks, Falcons, & Caracaras
• Falcons are small, speedy BoP that rely on aerial agility
• Typified by long tail and sharp wings
• Feed on birds, small mammals, insects and even bats
Birds of PreyHawks, Falcons, & Caracaras
• The laughing falcon is found along forest edges
• Loud call• Eats snakes (and
others)
Birds of PreyHawks, Falcons, & Caracaras
• Forest falcons are grayish falcons that lurk in the forests, often sitting motionless
Birds of PreyHawks, Falcons, & Caracaras
• Yellow-headed Caracara is extremely common and can be seen in flocks
• Why flock?– Carrion feeders…
what is the limitation?
Birds of PreyHawks, Falcons, & Caracaras
• The largest Neotropical bird of prey are eagles and hawk-eagles (3sp)– Ornate hawk-eagle– Black hawk-eagle– B&W hawk-eagle
Birds of PreyHawks, Falcons, & Caracaras
• Harpy eagle is a huge predator (>1m) with very thick legs
• Territories frequently exceed 100km2
• Strictly a forest dweller
• Eats monkeys and sloths
Birds of PreyOwls
• Owls (Strigiformes) has two groups, the barn owls (Tytonidae) and typical owls (Strigidae)
• 24 neotropical birds
Birds of PreyOwls
• Spectacled owl is the largest Neotropical owl (19”)
Birds of PreyOwls
• B&W owl
Mottled owl
Birds of PreyOwls
• It is not uncommon to see pygmy owls (6”) during the day
the Southern Invasion
• During the autumn, approximately >50% of birds breeding in North America head south
• The majority pull up in C Am, but many continue to S Am while still others winter in the West Indies
the Southern Invasion
• The abundance of migrants is high, but central America is 1/8th the size
• Consider dry forests of western Mex– Summer 2 birds/ha– Winter 64 birds/ha
the Southern Invasion
• Many of the species are not migrating away from the harsh winter of the temperate zone but rather returning home to the tropics from ‘seasonal bounty’ of the temperate zone
• E.g. tyrannid flycatchers, hummingbirds, tanagers, orioles and wood warblers
the Southern Invasion
the Southern Invasion
• Many species come down and take advantage of brushy habitat
• E.g. GRCA, NOYE, YBCH• Others take advantage of the forest• E.g. WOTH, OVEN, AMRE, other
warblers• Still others occupy successional
habitat
the Southern Invasion
• Other species have relatively large dietary shifts in the tropics and some become frugivores
• E.g. NOOR, OROR, SCTA, SUTA
the Southern Invasion
• The degree to which migrants interact with local species probably varies across space and time and will be dependent upon local resources and the abundance of competitors
• E.g. on BCI, several migrants actively prevented from joining in mixed-antbird flocks
• In Amazon, many migrants join
the Southern Invasion
• At least some species move in and become part of the larger avian community
• Several species, WOTH, OVEN, GRCA (and other species as well) all occupy the same locations from one year to the next
Site fidelity