Market Hunting - See text

Midcontinent Light Geese Example

Includes Greater and Lesser Snow Geese (blue and white color phases)and Ross geese

Greater and Lesser Snow geese on Atlantic and Mississippi Flyways Use Hudson’s Bayas breeding ground and stopover areas (“Midcontinental light geese”)

Why the Increase?1) Agriculture2) Sanctuaries3) Reduced Hunter Harvest4) Climate shift on BG

Result:Higher adult survival/conditionHigher repro

Population sizes from 1968-1993

1965 present:

Greater Snow 30,000 600,000 Lesser Snow 1 3 millionRoss 30,000 400,000

Goose “grubbing” for rhizomes & tubers results in majorshifts in vegetation

Hudson Bay Study Site1984

1997

Is it really geese?

Is it really geese? – The exclosure experiment

At Hudson Bay 35% of habitat destroyed, 30 % damaged, 35% overgrazed

1) Season

2) Method of Take

3) Bag Limit

4) # of Hunters

5) Which animals

Recall the ways hunting can be used to alter outcome:

Management Response 1999Conservation Order Light Goose Hunts ordered by USFWS

1) Extend Hunting Season into Spring2) Methods

Electronic callsNo limit on number shells shotgun contains

3) Bag limit No daily bag limit imposed, set by states

The management goal for light geese in the mid-continent region is to reduce the population by 50% from the level observed in the late1990s. The management goal for greater snow geese is to reduce the population to 500,000 birds.

USFWSFinal Environmental Impact Statement:Light Goose Management June 2007

Lethal Trapping - More controversial than hunting See Table 10-3 for pro-con views

Snare

Leghold trap

1994 AZ Ban on trapping on federal/state lands

Effect on harvest – lab exercise

Current Regulations:1) Only on private lands or special designations

2) License, written exam, course required

3) All traps labeled, padded jaws, offset

4) Checked daily, kill target or release non-target

5) Written annual report to AZGFD

Exemptions:

1) Livestock losses2) Federal, state, county, local health departments3) Rodent control

Examples of use of trapping:1) Mesocarnivores on refuges/breeding grounds

Garretson and Rohwer 2001. JWM 65:398-405.

16 41km2 sites, ½ trapped other not trapped Trappers paid $18,000 for 5 mos 2404 coons, skunks and foxes Response: Doubled duck nesting success 23% vs 43% and return rate(so what was management goal in this case?)

Recommendations:

1) Treat large areas, with high repro potential2) May not be necessary where coyotes prey

on coons, skunks and foxes

3) Need public acceptance – rural area so acceptance was… high or low?

2) Introduced Exotic Species Nutria (Coypu) Native of South America

5-8 young/litter 2-3 litters per year

Introduced for fur in 1930’s

Intro in La in 1930 – 20 million by 1950

1970 – 10,000 trappers in La1998 - 1,700

Effects:Destroy leveesConsume cropsConvert marsh to open waterCost: millions of $

Chesapeake Bay of Maryland

CONTROL Options???

Lethal Trapping – worked in Great Britain where coypu eradicated

Alternatives to lethal trapping?

1) Live trapping and removal Cost Remove to where?

2) Contraception Cost Availability

3) Poison Non-target effects Reduced suffering? Limiting access

4) Reintroduce predators Feasibility Acceptance

Arizona’s Coypu?