Download Nest construction and variation and some material from Chapter 15

Sort of an
extension
from Chapter
15, will want
to know this
information
for Final.
NESTS, NEST
CONSTRUCTION,
VARIATION IN NESTS
BASED ON SPECIES
After this we’ll
look at some
nests
(exercise
here) and do
statistics for
project.
NESTS
 Nests are used primarily for the raising of young
 Incubation of eggs
 Brooding of nestlings (altricial species)
 There are a few species that build ‘ dormatory’ nests
for non-nesting purposes – we won’t worry about
them
 Monk Parakeets (Myiopsitta monachus) in New Orleans do this
 There are a few species where males build display
nests that aren’t used – we won’t worry about them
 Carolina Wrens (Thryothorus ludovicianus) will do this
 Focusing here on nests that are used during
offspring production
NESTS
Birds lay eggs, eggs
must be protected
and incubated
 Nest structure and
location important
Nest cup helps facilitate contact
between female and eggs, nest
content helps retain warmth
 Guarding against nest
predators
 Guarding against nest
parasites
 Consistent incubation,
may assist in
temperature regulation
NESTS
 Nest location and
placement can vary
strongly
 From tree tops and rocky
cliffs to underground or
sitting on the water
 Nest content can vary
 Sticks/twigs, grass, mud,
feathers, hair, bark
 All this impacts nest
microclimate
 Strong evolutionary
impact
The Wrinkled Hornbill (Aceros
corrugatus) is a cavity nester
NESTS – NOT REALLY A NEST?
The Australian Brush Turkey
(Alectura lathami) doesn’t build a
classic nest, instead it’s a mound
of rotting vegetation
Development and nesting behavior
of this species considered to be very
primitive
NESTS – WATER BASED
Both cases nests are built of rotting
materials (warmth?) and barely
above the water (safety). Most
loons and grebes build nests like
this.
Pacific Loon (Gavia pacifica) nest
above and Pied-billed Grebe
(Podilymbus podiceps) nest at right
NESTS – GROUND NESTS
NOTE: big size differences in offspring
Snowy Owl (Bubo scandiacus) nest
at left and a Brown Pelican
(Pelecanus occidentalis) below
Many species nest directly on the
ground in nests that may be made
of grass or twigs, sometimes just a
scrape in the ground.
NESTS – GROUND NESTS
Northern Harrier (Circus cyaneus) nest
at above left, King Eider (Somateria
spectabilis) nest lower left, Laughing
Gull (Leucophaeus atricilla) nest below.
NESTS – GROUND NESTS
Note that species
that nest on the
ground are often:
 Large species
 Colony nesters
 Found in inaccessible
areas
 Cryptic in nature
 Dangerous predators
in their own right
Arctic Tern (Sterna paradisaea)
Royal Tern (Thalasseus maximus)
NESTS – BURROW NESTS
Burrowing Owl (Athene
cunicularia)
Belted Kingfisher
(Megaceryle alcyon)
Many cases the burrow was constructed
by someone else, like a Gopher Tortoise
NESTS – CAVIT Y NESTS
Many species use cavities, some are primary cavity
excavators (like the Red-headed Woodpecker,
Melanerpes erythrocephalus) while others are
secondary cavity dwellers (like the Scarlet Macaw,
Ara macao)
NESTS – CAVIT Y NESTS
Great Horned Owl (Bubo
virginianus)
Prothonotary Warbler
(Protonotaria citrea)
Eastern Bluebird (Sialia
sialis)
NESTS
NESTS - ARTIFICIAL
Some species will readily accept man-made cavitities
NESTS - ARTIFICIAL
Peregrine Falcons (Falco peregrinus) nest on open cliff faces, hunt in open
areas. This has allowed them to adapt to human habitation and human
supplied ‘cliff’ faces
NESTS
Classic nest
found in tree or
shrub
NESTS – MATERIALS
 Materials used in nests
can vary widely as well
 Nothing (or next to it), just a
ground scrape or a few
sticks
 Grass
 Twigs, sticks, and bark
 Mud
 Construction can vary as
well
 Classic round nest shape
 Hanging baskets
 More exotic
Mourning Doves (Zenaida macroura)
build surprisingly scanty nests for such
a substantial bird
NESTS - SPECIALTIES
Tailorbirds (Orthotomus
sutorius) use a variety of
grasses and plant fibers for the
nest, and then have a unique
construction
NESTS – SPECIALTIES
A swift nest made from saliva, will
be used in bird’s nest soup
Barn Swallow (Hirundo rustica)
nests, above, are made of mud and
feathers, Monk Parakeets
(Myiopsitta monachus), right, use
grass to build large nest colonies
NESTS – SPECIALTIES
Chestnut-headed Oropendola
(Psarocolius wagleri) nests are finely
woven structures
Orchard Orioles (Icterus
spurius) build a hanging
basket type nest as well
NESTS
 Most nests that one could
see are going to be the
stereotypical ‘nest’
 Made of a collection of
materials (grass, twigs,
bark, hair, feathers
 An outer heavier layer
 An inner soft layer that
provides insulation and
cushioning
 Habitat used by the adult
often dictates what type
of nest you will see
Northern Cardinal (Cardinalis cardinalis)
Eastern Meadowlark (Sturnella
magna)
NESTS
A precocial waterbird species
like the Mallard (Anus
patyrhynchos) can have a
ground nest that is well
camouflaged until hatching, then
the hatchlings leave
NESTS
 Nest success varies with latitude, nest location, and
species size and offspring hardines s
 Predation, starvation, adverse weather – big causes of nesting
failure
 Nest success also varies with type of nest
 Cavity nesting species typically do better than open cup
nesters, or ground nesters
Song Sparrow (Melospiza
melodia) nestlings