Wolf Pack Dynamics Preliminaries

1
Wolf Pack Dynamics(Preliminaries)

• Virginia Stoll
• Wm. D. Stone

2
A Mexican Lobo
3
The Lobo

• Smallest subspecies of North American Gray Wolf
• 50 80 pounds
• 30 inches at the shoulder
• Original range much of Mexico, NM, AZ

4
History

• Almost extinct by mid-20th century
• Listed as endangered 1976
• Recovery effort started 1977
• Small population captured in Mexico
• Two small captive populations
• 7 founders.

5
Wolf Packs

• Basic unit of population the pack
• One alpha pair
• Normally the only breeders
• Young adults
• Help hunt and baby-sit
• Pups

6
Formation of new packs

• Young adults can leave the pack become lone
  wolves
• New packs can be formed by a pair of lone wolves
  joining up
• Very large packs can split
• Death of one of the alpha pair can cause pack to
  split

7
Pack size

• Prey
• Size
• Mostly elk
• Availability
• Lots of elk
• Scavengers
• Ravens
• Can eat 2 lbs. of meat per day each

8
Population Pressures

• In the New Mexico re-established wolf population,
  two largest sources of adult mortality are
• Cars
• Illegal shooting

9
Natural Mortality

• Food pressure mostly affects survival of pups to
  weaning
• Inter-pack battles can be a significant cause of
  death

10
Genetics

• Starting with tracking one locus, with one marked
  gene in a single individual
• Probability of duplicate copies in an individual
• (comparative only)

11
Input from Federal Wolf Biologists

• New Mexico packs rarely are larger than a
  breeding pair plus pups
• Subspecies difference?
• Growth stage vs. steady state?
• So far, little food or territory pressure

12
Genetics

• US Fish Wildlife has full genetic profiles of
  every wolf they have handled
• Very small number of founders
• Selective breeding for genetic diversity
• They hope our model can help

13
Model Results
14
Female with pups