4: Surviving climate change

Question 1

Define Phenology

Answer 1

Timing of seasonal activities of animals and plants
E.g
Arrival of migrants
Appearance (e.g butterflies, buds)
Breeding

Question 2

How can we be sure changes in phenology are due to climate?

Answer 2

• Need to compare across decades of data (natural historians, monitoring surveys…)
• Need to control for confounding variables → is it really climate change driven
• Relate phenology with climate

Question 3

List some of the benefits of phenological change to organisms

Answer 3

Exploit these optimal climates earlier in the year
Early access to best nesting sites & abundant food (Improved survival of young)
Potential to make more breeding attempts

Question 4

List some of the costs of phenological change to organisms

Answer 4

Sudden bad weather kills (adults or young)
Temporal mismatch with food
Phenology shifts in species, not its food
E.g timing of bud burst and egg hatching is more mismatched

Question 5

Are species shifting their distributions?

Answer 5

Yes,
- Study on butterflies shows they are shifting North
- Study on tropical mountain moths shows they are increasing their elevation

Question 6

When investigating phenological changes, alongside temperature, what variable may have been overlooked?

Answer 6

Precipitation

=If only focus on poleward shifts, would underestimate shifts in climate niches by 26% in temperate and 95% in tropical species

Question 7

Research shows organism shifts (especially elevation) are not as fast as predicted, why could this be?

Answer 7

• Species simply cannot move quickly enough
• Data used in prediction are too coarse scale ?
• Temp grid cells at 1 x 1 km or larger (very big)
• Use weather station data → not actually how species experience climate

Question 8

Describe microhabitat buffering + give some examples

Answer 8

→ fine scale (cm - m) features within a habitat
Large temp variation in much smaller scales

E.g
Epiphytic ferns
Tree holes
Leaf litter

Question 9

Do microhabitats allow species to survive under harsh conditions?

Answer 9

• Study in Philippines shows organisms were less exposed to their ‘death zone’

Question 10

Describe the opposing climate gradients in elevation vs forest height

Answer 10

Colder at top of mountain and warmer at bottom
= species increase elevation due to increasing temps

Warmer at top of tree than bottom
= Species decrease elevation in forest due to increasing temps

Question 11

Describe the findings of Scheffers study into microhabitat temp gradients

Answer 11

• Temp gradients steeper at the tree scale than the elevation scale
  = easier for animals to move down the tree than move up a mountain
• Moisture gradients also steeper at the tree scale than elevation scale