reading 4 - mountain pine beetles

Question 1

1. How has the elimination of some forest fires contributed to the mountain pine beetle problem in British Columbia?

Answer 1

By eliminating forest fires, the beetles are able to feed on all of the fresh trees.

eliminating forest fires turns wood into “beetle buffets”. BC were packed with 3x as many mature pines as there would have been had they been allowed to burn naturally.

Question 2

2. What is the reason that some scientists believe that the beetle could potentially spread all the way to the Atlantic provinces of Canada?

Answer 2

The beetles have already been found to colonize jack pines in Alberta and Saskatchewan, and there are jack pines that reach all the way out to Nova Scotia

Question 3

3. In the past, the relationship between beetles and the forest was considered mutually beneficial. Explain how that has changed in recent years.

Answer 3

In the past, pine beetles used to feed on old, weaker trees, which helped produce a healthier forest. In recent years, climate change has left healthy trees vulnerable to the beetle’s attack.

Question 4

4. Describe how female beetles have evolved to survive the natural defenses that the trees produce.

Answer 4

The trees produce resin to flush the beetle out, but the beetle has evolved to ingest the resin and turn it into a pheromone, which sends a message to other beetles to congregate.

Question 5

How has the beetle indirectly impacted both water resources for people and salmon in waterways?

Answer 5

The pine beetles cause the trees to die which leads the unshaded snow to melt faster, causing rivers to crest earlier, which affects people and the ecosystems during dry season. It also affects salmon by slowing snowmelt, keeping the water cool during the spring

Question 6

6. Explain what is meant by tipping an ecosystem. Why are the beetles only partly to blame for such a phenomenon?

Answer 6

It means that an ecosystem is changing due to a phenomenon.

Beetles are only a partial factor, as global warming is the main factor driving all of this as the secondary effects are devastating.

beetles added stress to already drought-stressed forests; Rising temperatures, a key factor to droughts, as they pull moisture from leaves and soil