Flashcards in // lecture 30 Deck (38):
Plants & animals can grow, survive, and reproduce
only in specific climatic conditions
First climate classification systems were based on ecology, and
relationships exist between the annual variation of temperature and precipitation and the kind of vegetation/
ecology that exists on land and in the ocean (ocean also depends on currents/upwelling.
Many non-climate driving forces affect species:
Invasive species, Natural disturbances (e.g., wildfires), Pests, Diseases, Pollution, Agriculture intensification, Habitat fragmentation. these influences are often much larger than climate-induced changes. also nature is unpredictable.
climate impacts on wildlife
lost habitats, shifts in timing of predator-prey or symbiotic relationships, temp. thresholds, shifting ranges and adaptation, if possible, and temperature or water dependent pests and diseases
- Earlier springs have led to earlier nesting for 28
migratory bird species on the East Coast of the United States.
- Northeastern birds that winter in the southern
United States are returning north in the spring 13 days earlier than they did in a century ago.
- In a California study, 16 out of 23 butterfly species
shifted their migration timing and arrived earlier.
some species have moved
poleward and upward to adjust to temp. changes.
edith's checkerspot butterfly range changes:
- Populations are decreasing rapidly in S. Calif./Baja.
- B.C. and mountain populations are still thriving.
- Individual butterflies don’t move: just species in
colder locations have been more successful .
quino checkerspot butterfly (subspecies of edith's checkerspot)
- Endangered, biggest threat is urban development.
- First species for which climate change is officially listed as a
threat & factor that must be considered for recovery. recovery would be easiest in southern range of species because less development is occurring there.
- some scientists have suggested assisted migration.
Species are relocating to areas with more tolerable climate conditions. particularly threaten species that: cannot move fast enough and depend on conditions that are becoming more rare (like sea ice).
birds have shifted their range
data from xmas bird count performed every yr by volunteers. shows 35 mile shift over last 40 yrs.
cold water fish habitat
- As rivers and streams warm, warmwater fish are
expanding into areas previously inhabited by coldwater species.
- As waters warm, coldwater fish, including many highly-
valued trout and salmon species, are losing their habitat, with projections of 47% habitat loss by 2080.
- In certain regions in the western United States, losses of
western trout populations may exceed 60 percent, while in other regions, losses of bull trout may reach about 90 percent.
- Range shifts disturb the current state of the ecosystem
and can limit opportunities for fishing and hunting.
cold water fish
trout and salmon
warm water fish
catfish, bass, perch
lives in mountains in western US/Canada. makes a distinctive whistling noise and have dense fur, well suited to cold temps.
pikas and global warming
- can get heat stroke and die after brief exposure to temps. above 78 F. heat can lead to less time for foraging in addition to direct harm.
- local extinctions have occurred in several populations in the US already. live essentially on high-altitude islands of colder temps. migration to higher altitudes or more northern locations is not always possible.
like snow because they store food for later use. bear their young very early in feb. carnivore, but not top predator. must occupy a niche, rocky frozen areas.
food web disruption: arctic
- Not only is the decline of sea ice impairing polar bear
populations by reducing the extent of their primary habitat, it is also negatively impacting them via food web effects.
- Declines in the duration and extent of sea ice in the
Arctic leads to declines in the abundance of ice algae, which thrive in nutrient-rich pockets in the ice.
- These algae are eaten by zooplankton, which are in turn
eaten by Arctic cod, an important food source for many marine mammals, including seals.
- Seals are eaten by polar bears. Hence, declines in ice
algae can contribute to declines in polar bear populations.
cloud forests of central america
cloud mist critical to getting wet habitat biome through dry season. clouds shade forests too and suppress evaporation that way.
Monteverde Cloud Forest, Costa Rica
an example where development has been stopped by purchasing the land, but climate and habitat fragmentation still a threat. warming seems to be contributing to drying and the biology has repsonded.
cloud forest meteorology
- cloud forest of costa rica
- easterlies come from caribbean side and provide clouds in the mountains even in the dry season.
- this allows huge species diversity and some special species that would not otherwise exist.
animals of the cloud forest
sloth, gloden toad, quetzal
loss of frog species is altitude dependent
much high fraction of Atelopus are lost in altitude range 1000 to 2400 meters elevation - 90%.
climate change, along with
habitat destruction and pollution, is one of the important stressors that can contribute to species extinction.
The IPCC estimates that
20-30% of the plant and animal
species evaluated so far in climate change studies are at risk of extinction if temperatures reach the levels projected to occur by the end of this century.
Global rates of species extinctions are likely to
approach or exceed the upper limit of observed natural rates of extinction in the fossil record.
Examples of species that are particularly climate sensitive and could be at risk of significant losses include animals that are
adapted to mountain environments, such as the pika; animals that are dependent on sea ice habitats, such as ringed seals and polar bears; and coldwater fish, such as salmon in the Pacific Northwest.
- In addition to moving in location (higher latitudes or
higher elevation), species can shift in time too.
- spring is happening 5-15 days earlier.
Some seasonal biological activities are happening 5-15 days earlier than several decades ago:
trees blooming earlier, migrating birds arriving earlier, and butterflies emerging earlier. changes in timing differ from species to species, so ecological interactions are disrupted.
is when things used to
happen at the same time, but are shifting.
Disrupted Synchrony: Shrimp
- Hatching of shrimp larvae
match timing of phytoplankton bloom in
- Cue for shrimp larvae is
temperature at ocean bottom.
- Phytoplankton bloom is
timed to sun.
13 and 17 year Magicicada Synchrony
A species of Cicada comes out of the ground in synchrony every 13 or 17 years, depending on subspecies.
- Overwhelm predators with sheer numbers – predator satiation – when billions come out at same time every 17 years.
- Because of long prime number cycle, difficult for specialist predator to develop to be ready to eat/breed when cicada’s make their rare, but spectacular emergence.
climate warming is largest in the
high latitudes. but organisms in high latitudes are used to temp. changes (20-30 C changes from winter to summer every year). in the tropics temp. changes are much smaller. time and evolution have made tropical species less adapted to temp. swings.
temp changes in high latitudes vs tropics
in high latitudes, temp. changes are more, but will not be outside range of fitness. in tropics, may hit temps. which threaten survival of species.
large amount of biodiversity in the tropics. the idea that tropical species are hurt more is true for many species: insects, turtles, lizards, and frogs & toads. high metabolic rates requiring more time spent getting food important for cold-blooded animals.
Amphibians & reptiles are particularly vulnerable
- Cannot maintain their internal body temperature (cold-blooded).
- Many species are disappearing.
- Diseases spreading more easily due to climate has been
implicated in some extinctions. Ex: Frog extinction due to fungus (growing due to increased
- Often fragmentation of ecosystems, pollutants are to blame for unhealthy populations.
many will likely increase with warmer and moister climates.
caused by mosquitoes. cold weather kills mosquitoes. spreading into regions of African highlands not previously seen. we are stropping the spread of malaria faster than it is expanding though. and further attention to prevention could likely offset any climate effect.
- spreading across north america due to warmer winters and increased drought.
- Montana, Wyoming, Colorado pine forest are particularly hit hard. Also WA, BC, Alberta.
- often attack already weakened trees (by drought, etc.). can lead to forest fires.