Wildlife Control

Question 1

Reasons for pest control

Answer 1

• damage agricultural and horticultural crops
• forestry dmage
• ecosystems
• competition with livestock for feed
• risk of predation of livestock and farmed fish
• risk predation of endangerered wildlife
• risk of transmission of speicifc diseases to livestock
• risk of zoonotic diseases spreading to man
• property damage
• consumption and contamination of stored feedstuffs
• risk of overpopulation and emaciation of the species (eg. flamethrowers mice!)

Question 2

egs. pers control for animal dz control

Answer 2

• m bovis and brushtail possums (New Zealand)
• m bovis and badgers
• maintainance hosts and spill over hosts

Question 3

Maintainance or spillover hosts most important for disease control?

Answer 3

> maintainance

- spillover only important if levels in maintainance hosts so high above threshold then control both

Question 4

egs of zoonoses transmitted by wildlife?

Answer 4

> aveolar hydatid disease (e. multilocularis) 
- urban foxes
> haemorrhagic fever with renal syndrome (hanta virus)
- rats
> leptospira
- rats
> bird flu (avian influenza A H5N1)
- wild waterfowl 
> toxoplasmosis (toxoplasma gondii)
- feral cats
> lassa fever (arenaviridae)
- mice

Question 5

3 componenets of approach to wildlife control programme

Answer 5

• set clearly defined objectives
• decide how to achieve
• monitor outcome of plan
  > goals should be transparent and defensible when when outcomes are uncertain

Question 6

2 main control strategies

Answer 6

> damage control 
- deterrents
- exclusion 
> pest control 
- sustained destruction 
- eradication

Question 7

eg. repellent, deterrant and ecclusion devices

Answer 7

• noise emitters (bird scarer, u/s alarm)
• visual scarers (scarecrow)
• chemical repellents (copper acetate to repel sharks)
• habitat removal (roost removal around fruit farms)
• eclusion (electric fencing, vermin proof dororways)
• feed competition (encouraging competitiors less of a pest)

Question 8

potential impacts of wildlife control

Answer 8

• removing predators reshuffles food chain

- increased growth of other predators etc.

Question 9

egs of pest control methods

Answer 9

• toxicants
• traps and snares
• introducing disease
• inctroducing predators
• hunting/shooting/fishing
  > bounties
  > recreational hunting (does have an impact)

Question 10

Monitoring outcomes of wildlife control

Answer 10

• kill rates
• elimination rate (proportion removed in a given period, need to know how many badgers were in the envinroment initially)
• impact rate (improvement in resource, change in pest density etc)
  > measured by
• catch rates
• scant density
• feed removal/activity at bait stations
• head counts/plot occupancy
• renway/borrowing opening counts
• impact assessment (looking at incidence of disease, regrowth of trees etc.)

Question 11

define welfare compromise equation

Answer 11

W = N*I*D*C
w=welfare
n= no animals
I=intensity
d= duration 
c= capacity of the animals to suffer

Question 12

eg UK LEGAL toxicants

Answer 12

> alpha chloraslose
- only works very small aniamsl mice and shrews
- developed as an anaesthetic (causes hypothermia)
anticoagulants (vit K antagonist)
- 1st gen (warfarin)
2nd gen ( brodifacoum etc.)

Question 13

Is potassium cynanide a good toxicant?

Answer 13

• very humane
• acute acting toxin
• fast acting
• NOT LEGAL UK (human health risk)
• but rodents often will not consume full lethal dose -> bait shyness d/t sickness

Question 14

How do acute and cumulative toxicants differ

Answer 14

• acute more welfare friendly IF consume lethal dose

- cumulative don’t associate food with sickness 3-4d cumulation but then 4d suffering from haemorrhage esp into joints

Question 15

concerns of ingested toxins

Answer 15

> mode of action 
- intesntiy and duration suffering
> non-target poisoning
- wrong species eats it  
> 2* poisoning 
- eating carcasses
- predators often have high levels -> delayed onset decrease in population 
> sub lethal poisoning