Lecture 11- Introduction to Birds Flashcards
(23 cards)
How old were the fossil feathers discovered in Koonwarra, Vic?
11O MYA
How old were the penguins & dromornithid tracks?
30 MYA
-first recognizable fossils in Australia
How old were the extensive fossils of wetland birds in Central Australia?
- 20 MYA
- also dicovered rare pigeons, eagles, rails, megapode & passerines
What was the Dromornis stironi aka Giant Demon Duck of Doom?
-'Mihirung paringmal’ (giant bird) • central Australia - 15 mya • Flightless, weight 500+ kg, 3m tall • related to geese -not clear what he ate, probably not carnivorous
How many species of birds are there in Australia and what is their size range?
- 800
- range from 8g Weebill to 45kg Emu
What are the four broad categories of birds in Australia?
- Long-established non-passerines of Gondwanan origin (emus, cassowaries, parrots)
- Australasian passerines descended from Corvid family (fairy-wrens, magpies, honeyeaters)
- Recent colonists from Eurasia (swallows, larks, cisticolas, some raptors)
- Introduced species (starling, blackbird, Indian mynah)
What evolution is in play in the similarity of Australian birds to the Northern hemisphere?
-• however, these examples illustrate convergent evolution, not relatedness • most Aust spp. are corvids,descended from ancestors of the crow family
What does corvid mean?
-descended from the ancestors of the crow family
What is convergent evolution?
-Evolution of similar features in unrelated species
-• DNA studies allow origin and evolution to be unravelled
• prove that Aust birds not derived from northern hemisphere stock - more closely related to each other than to N.H. look-alikes
What are the four mating strategies of birds?
- monogamy (M+F)
- polyandry (FMMM) =more males
- polygamy (MFFF) =more females
- {promiscuity (FFMM)?}=lot of males with lot of females
What are the five parental care types in birds?
- biparental = both parents stay
- paternal or maternal=only one parent stays
- none
- mound-builders= build mounts of rotting vegetation that warms the eggs
- cooperative= in groups
What are the surveying techniques for birds?
- census, monitoring
- capture and ringing
- DNA studies
What is the Atlas of Australian birds project?
Aim: - collect info on distribution and abundance of Australian birds - involve community
- commenced in 1998
- voluntary based
- Some conclusions:
- some supposedly migratory species are not - winter movement of birds from SW & Tasmania to NT
What is the Australian Bird and Bat Banding Scheme?
-commenced 1953
-• Coordinates all banding – 600 banders, 80-100k birds/yr – central database – train & license banders
• Banding permits – A class project leader – R class experienced bander – C class trainee
What do we learn from capture and ringing of birds?
- lifespan, movements, observations of behaviour
- international movements
How does life span of birds vary?
- a lot
- 1-48 years
What are the Wader birds an their characteristics?
- Wader birds(the ones near water) - migrating species (~3 million individuals)
- March - gather on Australian shores, then fly north
- 10-15,000 kilometers, lose 50% body mass
What do the studies using colour-rings tell us about birds?
• dispersal • pair formation • breeding success • interactions
-can tell individuals apart even from a distance do not need to disrupt them as with normal banding to read the number
What is the myswan.org?
- example of citizen science
- people report sightings of swans
What do the DNA studies tell us about birds?
• DNA fingerprinting - mating systems
• Molecular sexing of monomorphic species
- captive management - studies of sex ratios
How many taxa of birds are extinct and how many are threatened and why?
24 taxa extinct, 127 taxa threatened
– large birds (>500g) more likely to be threatened than secure
- smaller birds more likely to be secure than threatened
Where do lot of the threatened taxa nest?
26% of threatened taxa nest in hollows – large owls & parrots in particular
- 23.3% are ground-nesting
- 50 of 133 island taxa are extinct/threatened
What are the threatening processes for birds?
• clearance for agriculture • grazing • altered fire regimes • predation • direct exploitation - hunting - bird trade
