BIO3132 Lecture 8: Week 5. Bird Diversity II and Fish Diversity I
31 May 2018
School
Department
Course
Professor
Week 5. Bird Diversity II and Fish Diversity
AUSTRALIAN BIRD DIVERSITY II
Learning objectives:
• A oeie of Austalia ids
• The pehisto of Austalia ids
• Aia taoo
• Austalia as soue of old’s sogids
• Adaptatios to unpredictable environments
• Lack of migration/movement?
Australia
o No breeding land birds migrate trans-euatoiall do’t eed i Austalia that pass the
equator)
o Several nonbreeding migrants from Europe and Asia into Australia
o Bird migration is limited
Northern hemisphere (Australia)
o 66% of breeding species migrate in autumn (head south)
o Many migrate across the equator to south America (trans-equatorial)
• The environment is very unpredictable – strategies to deal with this:
Physiological
o Water retention (uric acid)
o Water uptake
o Salt glands (falcons)
o Cooling/heat loss (panting)
o Want to minimise the time drinking - predators
Feeding
o Granivores
o Insectivores
o Carnivores
o Distant daily movements
o Very few obligate nectivores – usually eat insects as well if conditions are
hard
o Resource tracking:
Nectar tracking
Invertebrates
Grains
-> move over vast distances for food
Movement
o Residents – around same area year round
o Migrants – move in a pattern (i.e. seasonal)
Breeding/non-breeding movements
Long distance/short distance
find more resources at oneclass.com
find more resources at oneclass.com
Latitudinal (moving south)
Longitudinal (moving west east)
Altitudinal (seasons)
o Nomads = resource trackers – a’t figue out hee the’e goig et
Breeding
• ~2.3 million land birds move through Torres Strait annually
• Nomadism:
o Birds can appear anywhere
o Implies a level of randomness
o Terminology reflects our lack of understanding
o Confused pattern of movement
-poal has udelig pattes that e’e uaae of
• Resource tracking:
o Movement away from poor areas
o Movement to productive areas
o Movement to more predictable areas
o All are elements that we are yet to predict accurately
• Breeding strategies:
Australia
Northern hemisphere
o Seasonal or flexible and responsive
-if good conditions = breed, not good = no
breeding
o Multi-clutched
o Small clutches
o Continuous when conditions are good
o Cooperative breeding is common
o Strictly seasonal
-only breed for ~2.5 months
o Single clutch
o Large clutches
o Cooperative breeding is uncommon
-do’t end up with large populations
• Boom and bust cycles:
o Many arid land species are adapted to this strategy
o Rapid response in population to good times
o Decline as conditions toughen
o Contraction back to refuge in tough times
o Pronounced fluctuations
o Eg. zebra finch:
Classic boom bust species
Remarkable strategies just recently revealed
Reetl eealed the ae’t poisuous
Strategy for droughts
Pairs continue to hand out during drought – do’t pat afte atig – pair bonds
are very strong
find more resources at oneclass.com
find more resources at oneclass.com
Breed quickly when conditions are good
• Desert mammals are similar
-> disappear and reappear
-contract back to ridges and refuge in desert, living on peaks
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Learning objectives: a(cid:374) o(cid:448)e(cid:396)(cid:448)ie(cid:449) of aust(cid:396)alia(cid:374) (cid:271)i(cid:396)ds, the p(cid:396)ehisto(cid:396)(cid:455) of aust(cid:396)alia(cid:374) (cid:271)i(cid:396)ds, a(cid:448)ia(cid:374) ta(cid:454)o(cid:374)o(cid:373)(cid:455, aust(cid:396)alia as sou(cid:396)(cid:272)e of (cid:449)o(cid:396)ld"s so(cid:374)g(cid:271)i(cid:396)ds, adaptatio(cid:374)s to unpredictable environments. Australia: no breeding land birds migrate trans-e(cid:395)uato(cid:396)iall(cid:455) (cid:894)do(cid:374)"t (cid:271)(cid:396)eed i(cid:374) aust(cid:396)alia that pass the equator, several nonbreeding migrants from europe and asia into australia, bird migration is limited. Northern hemisphere (australia: 66% of breeding species migrate in autumn (head south, many migrate across the equator to south america (trans-equatorial, the environment is very unpredictable strategies to deal with this: Feeding: water retention (uric acid, water uptake, salt glands (falcons, cooling/heat loss (panting, want to minimise the time drinking - predators, granivores. Insectivores: carnivores, distant daily movements, very few obligate nectivores usually eat insects as well if conditions are hard, resource tracking: Movement: residents around same area year round, migrants move in a pattern (i. e. seasonal) Altitudinal (seasons: nomads = resource trackers (cid:272)a(cid:374)"t figu(cid:396)e out (cid:449)he(cid:396)e the(cid:455)"(cid:396)e goi(cid:374)g (cid:374)e(cid:454)t.
