Climatic effects on species- range and behaviour

Every species has particular optimum environmental conditions for survival. As climate alters they either:

• Migrate (invading a new area and mixing with formerly non-overlapping species. This can lead to knock-on effects throughout the ecosystem and can cause extinctions)
• Adapt their behaviour

Changes in species distribution- Spatial

• Killer whales with tall dorsal fin are moving into previosuly ice-bound Artic waters and siplacing bowhead whales
• Adelie penguin rookeries being replaced by Gentoo penguins on the Antartic peninsulars
• 60 species of butterfly have moved north in Europe, e.g. Polygonia comma butterfly is spreading north in UK at a rate of 10km a year
• Concern that pests of species are linked with diseases could spread more widely, e.g. Anopheles mosquito which carries Malaria

Changes in species physiology and behaviour- Tempral

• Shifts in Phenology (timing of biological activities that take place seasonally)- migrant birds, butterflies and plants are arriving earlier.

Changes in physiology and behaviour- Tempral

• Polar bears find it difficult to hunt seals during the summer ice-free periods. As the Artic warms the Polar bears have become underweight as they have a shorter amount of time toi hunt for food.

What are the issues resulting from Climate Change??

Changing climates, shifting climatic belts and the effects on biomes

1. A change in that climate will therefore change that ecosystem
2. 'Macro-scale' effects

• Climatic ranges are moving North 50km-80km every 10 years
• Shifting climatic belts polewards (also known as the migration of climatic belts)

3. Shifting Climatic belts leads to changing biomes

• By 2100, 40% of biomes will have switched to a different state

Temperate Grasslands-Mid Latitudes

• Temperate Grasslands on the steppes of North Asia and North American prairies will have drier summers and colder winters.
• These regions are the 'bread baskets' of the world-the principle grain-growing areas
• Climate change will reduce grain yields,food production and income for farmers
• This could lead to food shortages

Tundra and Northern tree line-High Latitudes

• Melting permafrost leads to: Loss of habitats-wildlife adapted to survive tundra conditions, subsidence-damaging settlements,transport and oil pipelines in Alaska and Siberia, increased sediment in rivers- increased erosion of the banks affect wildlife including the salmon that migrate upstream to spawn.
• Release of methane and carbon dioxide previously locked up in frozen ground (positive feedback loop accelerating global warming)

Rainforest, Savanna and Desert-Low Latitudes

• Tropical biomes seem to be tied to specific climate tipping points (Gilf Kebir). When certain climatic thresholds are crossed (especially precipitation level/distribution), the one ecosystem can suddenly switch to another
• Could be beneficial to some areas-e.g. Sahel where movement of the rain belt Northwards could halt desertification