ADVANCED LEC 17 ORNITHOLOGY University of Rio Grande Donald P. Althoff, Ph.D. Reproduction Part II Reference Chapters

Which comes first…the egg or the nest? Thus far, have covered what the “laid” egg consists of… …but now how we got the egg being ready to be laid For those species that actually prepare a “nest”, they typically do so as the breeding/courtship process. This includes two phases: a) _________________= where b) _________________= what

Nest Site Selection Many species are very selective. They spend days finding the “spot”. For many species we’ve been able to quantity the apparent factors that result in placement. These include: a) _________________—both at the macro and micro levels(including species & density) b) _________________ c) ___________________________ d) _________________ e) __________—if above ground f) __________ (edge, interior, “scale-dependent”) g) _____________________________ e) etc.

Nest Site Selection…con’t Some species take little time to select a nest site. For example, some species of waterfowl may do what is referred to as “________ _________”. They simply use someone else’s nest. Ex. Wood ducks, redhead ducks, canvasbacks, ruddy ducks Many cavity nesters (i.e., _____________________ ) spend “no” time in nest preparation once cavity is identified…that is “excavating the hole” ↑ Wood duck “nest” in wood duck box…with over 25 eggs

Nest Building Sex that chooses site: may be the Male, may be the Female…may be both. ___________, though, it is the Female. Some species, like the marsh wren, it is the male that establishes the territory and builds several nests vs. Some species, like the red-winged blackbird that only establishes the territory and therefore is dictating the general location of nests but not the specific site of the nest.

Nest Building…con’t Some species: both sexes help build (ex. _________ –the lightning bird) or use old nests (ospreys, hawks) ____________: male gets the sticks, the female weaves them in. ____________: female gathers nest material, them male builds the nest

Nest Types Buried underground Substrate Cavity (both primary and secondary) Elevated red-eyed vireo prothonotary warbler ovenbird burrowing owl

Nests: Buried Underground Megapods (primitive family of gallinaneous birds) bury their eggs either by covering them in sand or covering them with vegetation ___________: Nest first lined with “rotting” compost. Then covered with sand. ____ keeps nest temp at 33 0 C ( F). Puts head into vegetation, sticks tongue out, and takes temp! --long incubation period --young are precoccial sand decaying veg soil

Substrate Nests: ___ nesting material Nighthawks, whip-poor-wills (on rock, on “random” leaves) Tropical birds—lay eggs on ground Skimmers Numerous shorebirds

Substrate Nests: Nest material present “Dry”—ducks gather nesting material by ____________ from eventual nest site—do not gather and/or carry material…and line with feathers (example: pintail) Some galliforms and swans also do this

Substrate Nests: Nest material present…con’t ____________— meadowlarks, grasshopper sparrows Often well- hidden…adult flies close to nest…then ‘walks’ the last few feet to it

Substrate Nests: Nest material present…con’t Floating nests— grebes, canvasbacks & redheads, ruddy ducks, some terns and loons (semi-floating) common loon western grebe

Cavity Nests _______ cavities: rough-winged swallows, kingfishers _______ cavities: a) _________—tree nesting ducks (wood ducks, mergansers, buffleheads) b) _________ = excavated—woodpeckers c) __________ = already excavated— chickadees, nuthatches, wrens, martins, owls

Cavity Nests: Red-cockaded Woodpecker A species that is a _______________ Construct their own cavities… usually taking ____ _______________. Have ___________ Key design feature: _________ around cavity causing tree to _______…which discourages snakes

Cavity Nests: Red-cockaded Woodpecker __________________…so much attention has been given to protecting habitat (80+ year pine stands—mostly longleaf pine) Have figured out “construction” details…so making some artificial cavities -- video 33+ minutes

Elevated Nests ___ nesting material a) fairy tern: depression in tree branch b) palm swift: glues eggs to leaves, usually palm leaves (uses saliva)

African palm swift

Elevated Nests…con’t Nesting material a) __________: mourning doves, herons, cuckoos b) __________: opening at top; globular 4 types: _____________—supported from below _____________—supported from the side _____________—supported from side and rim _____________—supported from top

Elevated Nest: STATANT American robin

Elevated Nest: ADHERENT Barn swallows Elevated Nest: PENSILE Cliff swallows

Elevated Nest: PENDULOUS Baltimore oriole Weaver finch

Elevated Nests… weaver finches Can tie ______________—and instinctive behavior pattern (see Gill Fig 15-9, p444) Pendulous nest has these advantages a) “___________” adaptation b) may be “_________” adaptation

Weaver finches: step-by-step construction Ring Roof Egg chamber Antechamber Entrance

Other Nest Types/Forms Colonial nests: social weaver from African savannah ft wide nests. Each bird with its own nest opening (like an apartment complex) Community nests: all females lay eggs in same nest. Example: ostriches

Cape cobra at a social weaver nest complex !

Hornbills Nest in tree cavities. After clutch is laid, ________ goes inside. Male then fills in opening with mud, leaving vertical slit opening just wide enough for his/her bill to fit through. She stays insides during _____________________________ …he feeds everyone through the slit