BIO205 Lecture 24
- Case study: do corridors have value in conservation?
- Why would conservation groups file a petition against a fence along the U.S. – Mexico border
o Policy; financial aspects; etc;
o In 2008, conservation groups against the fence for ecological reasons
- This is the reason:
Adult weight: 45-115 kg
Daily movement: at least 2-3 km
Home range: >10km^2
o Why is it more difficult for top carnivores to obtain sufficient energy resources than it is
for animals lower on the food chain?
Naturally, larger animals need more food resources in order to sustain their life
compared to small animals with small body sizes; creating a wall and limiting the
free range of the Jaguars’ movements means that they are confined to smaller
areas and eventually deplete those areas of resources
Lower trophic level organisms requires less energy than higher tropic levels
because energy level is lost for every single lower step of the trophic level
The hunting methods of carnivores requires more energy and so in the end,
they still need more resources
Available energy decreases with increasing trophic level
o What sort of genetic changes are more common in smaller populations than large ones?
Are these problematic and, if so, how?
Inbreeding in smaller populations
o Is it important for people to try to protect endangered species?
Yes because to create diversity of species
See discussion during lecture 23
- How to protect jaguars?
o Population size is uncertain, but most likely small
o Options for protection:
Elimination of barriers such fences, roads, urban sprawl
Connect habitat through corridors
o What does island biogeography suggest about the ideal design of a protected area?
Protected area should be large and close to ‘mainland’, and preferably round
to avoid edge effects
o What are some of the reasons why the number and size of protected areas is limited? Finance of interest
Increase of human population which needs living spaces
Hard to find enough space for jaguars
Expense, limited avail