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The Cognitive Dog

The Cognitive Dog. Class 3: Wolf and Wild Canid Behavior. Agenda . Questions from last week Plan for next week The brain trust: part 2 Wolves & coyotes. Plan for next week. Perception: readings

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The Cognitive Dog

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  1. The Cognitive Dog • Class 3: Wolf and Wild Canid Behavior

  2. Agenda • Questions from last week • Plan for next week • The brain trust: part 2 • Wolves & coyotes...

  3. Plan for next week • Perception: readings • Coren, S. (2004). How Dogs Think: Understanding the Canine Mind. New York, NY, Free Press. Chapters 2-4. [Book] • Harrington, F. H. and C. S. Asa (2003). Wolf Communication. Wolves: Behavior, Ecology and Conservation. L. D. Mech and L. Boitani. Chicago, IL, University of Chicago Press: 66-103. [Course Pack] • McGreevy, P., T. Grassi, et al. (2004). "A Strong Correlation Exists between the Distribution of Retinal Ganglion Cells and Nose Length in the Dog." Brain, Behavior and Evolution 63(1): 13-22. [e-journals] • Quaranta, A., M. Siniscalchi, et al. (2007). "Asymmetric tail-wagging responses by dogs to different emotive stimuli." Current Biology 17(6): 199-201. • CB: Is knowing wolf behavior useful when training dogs?

  4. The brain trust...

  5. The brain trust • Lalu & Kindy

  6. The brain trust • Tucker & Ella

  7. The brain trust • Halle & Brody

  8. The brain trust • Sir, Yes Sir, Right Away Sir, I am not worthy Sir...

  9. Week 3: what do wolves really do... • People look to wolf behavior to... • explain dog behavior • justify training techniques • How well does the folk mythology regarding wolf & wild canid behavior reflect reality? • Is the paradigm even useful?

  10. A family tree, of sorts... • Based on a statistical analysis of DNA... • Grey wolf is closest relative to domestic dogs • Gray wolf & coyotes appear to have a common ancestor approx. 1 MYBP • The evolution of dogs from wolves will be the topic of classes 5&6 Ostrander, E. A. and R. K. Wayne (2005). "The canine genome." Genome Research15: 1706-1716.

  11. weight: 10/12 kg length: .8/.85m weight: 37/40 kg length: 1.0-1.6m Wolves are the largest of all wild canids • but coyotes may be the most versatile

  12. Macdonald: why some canids live in groups (or how the reality of making a living shapes behavior)

  13. Reality of life shapes canid behavior, e.g. Hrs spent hunting • For wild dogs, hunting requires a lot of energy relative to the energy gain associated with consuming the kill... • If they lose even a small portion of the kill to hyenas, the hrs required to break-even goes up exponentially... • So wild dogs tend to avoid niches occupied by hyenas... % loss to hyenas MacDonald, D. W., S. Creel, et al. (2004). Society. Biology and Conservation of Wild Canids. D. W. MacDonald and C. Sillero-Zubiri. Oxford, UK, Oxford University Press: 85-106.

  14. Large predators need large prey to survive... • Canids as a group break down into 2 categories... • Above 20kg (wolves & large coyotes) • Feed on prey larger than themselves • Below 20kg (dogs, foxes) • Mostly feed on small prey (< 2kg) MacDonald, D. W., S. Creel, et al. (2004). Society. Biology and Conservation of Wild Canids. D. W. MacDonald and C. Sillero-Zubiri. Oxford, UK, Oxford University Press: 85-106.

  15. Costs and benefits of living in groups • Putative Benefits • larger group aids in hunting and/or protection from scavengers • larger group reduces risk of predation • help with raising pups • Conditions that can reduce costs of living in groups • abundant prey (food for all) • dispersal is costly (cost of sticking around less than cost of dispersing...) • But what does the data suggest?

  16. Benefits: strength in numbers • Conventional wisdom is that hunting in groups pays off • Little evidence that it does • Only one or two individuals needed to bring down prey • Food winds up being shared by group (free loaders...) • Example from wolves suggests pair does best, but... MacDonald, D. W., S. Creel, et al. (2004). Society. Biology and Conservation of Wild Canids. D. W. MacDonald and C. Sillero-Zubiri. Oxford, UK, Oxford University Press: 85-106.

  17. gazelles wildebeest MacDonald, D. W., S. Creel, et al. (2004). Society. Biology and Conservation of Wild Canids. D. W. MacDonald and C. Sillero-Zubiri. Oxford, UK, Oxford University Press: 85-106. prey by size of pack Depending on prey, more may be better up to a point

  18. Benefits: strength in numbers... • Peterson & Ciucci: 1 wolf might lose 66% of his moose to scavengers, a pair 50%, but 10 wolves only 10%. • Vucetich & Peterson observe that while larger packs may result in less prey caught per capita, it may also reduce the amount of food lost to scavengers... • In fact, when loss to scavengers was taken into account “the relationship between net rate of food intake and pack size was positive.” • But, this is dependent on the size of the prey. If the prey is smaller and can be consumed quickly, the losses to scavengers is reduced. • So some evidence that pack size increases with prey size, but seems pretty murky

  19. Benefits: strength in numbers • Increased group size may help with territorial defense... • The example of the coyotes from Bekoff: the decision to attack intruders seemed correlated with the # of intruders, so it pays, if you are a coyote to travel in packs • May also help in protection against predators... • Before re-introduction of wolves into Montana, 62% of the coyotes studied traveled alone, vs. 29% in pairs. After re-introduction, 48% in pairs, and 33% in larger groups.

  20. Benefits: strength in numbers • “...collaborative care of young may be a more fundamental (and certainly more ubiquitous) feature of canid society than the historically much vaunted cooperative hunting.” • Bring back food to the pups (although breeders bring back most) • Guard pups from predators • Whether this results in greater reproductive success is less clear. Macdonald gives example of wolf packs: when food is abundant, helpers increase survival, but when food is scarce, they reduce survival.

  21. Resource dispersal hypothesis • The argument here is that even in the absence of tangible benefits to living in groups, the structure of the ecological niche may make groups feasible. • The benefit may be small, but... • The cost is even smaller, so why not...

  22. Inspired by diagram found in lecture notes: www.montana.edu/~wwwbi/staff/creel/bio405/405lec8.pdf Resource dispersal hypothesis • Resource dispersal hypothesis: nature of food source (quality and its spatiotemporal characteristics) may influence size of territory and size of pack

  23. The Synthesis... • Wolves specialize on large ungulate prey... • run away and need to chased over large distances • found in ‘clumped mobile’ herds • individuals are big enough that 1 or 2 animals can’t consume it all immediately. • scavengers are a real problem • Large territory & territory sufficient to support 1 breeding pair can support additional members and they bring benefits...

  24. Mech, L. D. and L. Boitani, Eds. (2003). Wolves: Behavior, Ecology and Conversation. Chicago, IL, University of Chicago Press. Pack size may be loosely tied to prey size • Note how small they are when feeding on garbage

  25. So what is a wolf pack & what do we know about wolves?

  26. Mech’s comments on pack size... • The pack as nursery • Prey size may matter, but if so, mostly about sharing surplus • Breeding pair do most of the hunting, unclear the degree to which yearlings contribute • Trade-off: more hunters, less food per hunter, but less lost to scavengers, and more may get carried back to pups

  27. What is a wolf pack? • A typical wolf pack is a family group... • The breeding pair • Yearlings • Pups • Founded by an unrelated pair after dispersing • Moves in an ‘exclusive territory’ that it defends from strange wolves

  28. Variations in pack structure... • Typically 1 breeding pair per pack • Ovulation may be delayed until 2-4 years old • Behavioral suppression (including stress) • Often if another female has pups they don’t survive • ‘Tenure of breeding pairs’ typically lasts 3-4 years • Variations on nuclear family, extended family and disrupted family

  29. Courtship and reproduction • Very much tied to the seasons... • In autumn, testosterone & estrogen levels rise in males and females • Wolves go into estrus between late January - early April • Proestrus lasts longer in wolves than in dogs (2 weeks vs. 1 week) and estrus lasts longer as well (up to a month) • Dogs housed with captive wolves become photoperiodic • Fights among males tend to go up in the fall/early winter

  30. Courtship & reproduction • Gestation lasts 60-65 days in wolves vs. 65 days in dogs • Members of pack may participate in digging the den... • Behavior triggered by high level of prolactin • Social faciliation: observing mom dig triggers digging (the yawn effect) • Average litter size is around 6 pups • Pups are born early to late spring when ‘the living is easy’: easy for the pack to provision mom and later the pups.

  31. Stages of development... • More details on this in a couple of weeks • 4 basic periods • neonatal: birth to eyes opening & standing/walking (12-14 days) • transition: from 12-14 days to 20 days (startle) • imprinting & “I know this thing in my environment” • socialization: from 20 to 77 days • juvenile: from 11 weeks to maturity (4-10 months begin to join in hunts)

  32. Notes on feeding & following... • At 5 weeks, pups will follow Mom if she interrupts nursing. This quickly becomes “follow a departing adult moving in an intent, directed fashion” [Packard] • Pups are weaned during socialization (5-10 weeks) replacing milk with food provided by adults and yearlings via ‘regurgitative provisioning’ • Following Mom generalizes to following pack member who feeds them • When pack member approaches, the pups rush them and perform “lick-up” • Regurgitative provisioning is a key source of food for pups

  33. Regurgitative provisioning • Adults & yearlings gorge at site of kill • competition from con-specifics • prevent loss to scavengers • May also carry back food in mouth • ‘Lick up’ causes them to regurgitate food • In study, amount thrown up was 2.4 - 16 lbs of meat.

  34. Regurgitative provisioning • During neonatal and transition phase, mom gets most of food, and dad does most of the provisioning. Doesn’t mention role of yearlings • example of indirect care. • During socialization phase, mom competes with pups for food, but also heads off to hunt as well. • In study, pups received 81% of meat whereas mom received 14% (if you figure 6 pups, that means each is getting 12% of meat), and the others received 6%.

  35. Something to think about... • Regurgitative provisioning is common in wolves, but rare in pet dogs... • Wolves: nurse -> provision -> hunt/feed at kill • Dogs: nurse -> feed • Why is this? Does it reflect scavenger origins of early dogs? • What are the implications of this, if any? • Does RP in wolves help bootstrap prey identification (smell at least)/taste preference?

  36. Dispersal • Most wolves disperse from home pack between 9 and 36 months (Mech suggests 11-24 months) • Mech refers to a pack as a ‘dispersal pump’ • Also has nice image of “pulsating” as dispersers go out and come back • Peaks during periods of social and food competition Mech, L. D. and L. Boitani, Eds. (2003). Wolves: Behavior, Ecology and Conversation. Chicago, IL, University of Chicago Press.

  37. Mech, L. D. and L. Boitani, Eds. (2003). Wolves: Behavior, Ecology and Conversation. Chicago, IL, University of Chicago Press. Dispersal distances can be quite far • Distance & direction is poorly understood

  38. Finding a mate & territory • Mech suggests disperser needs to find and acquire 3 things: a mate, food resources, and an exclusive territory • Mech suggests choices: usurp a breeder within a pack, join a pack and lure out a mate, or disperse to edge of population in hopes of finding a mate who is doing likewise. • 3rd scenario seems to be common • Howling and scent marking used to advertise availability (mostly done in wolf-free areas) • Mech suggests that finding a mate may be a matter of days once there are a pair of wolves in a given area

  39. Wolves and territories... • Wolves are territorial • Size of territories is quite variable (13 sq miles for a pack of 6 in MN to 1693 sq miles for a pack of 10 in AK.) Poorly understood but... • Function of pack size • Prey biomass • Type, size & range/habits of prey • Territories in lightly saturated areas may be more dynamic than in saturated areas.

  40. Defending territory • Scent marking on border • Howling is a long distance signal (11 km in forest, 16 km on open tundra) • Active defense. Wolves take this seriously even when food is abundant. Mech, L. D. and L. Boitani, Eds. (2003). Wolves: Behavior, Ecology and Conversation. Chicago, IL, University of Chicago Press.

  41. Hunting & do wolves engage in cooperative hunting?

  42. Mech, L. D. and L. Boitani, Eds. (2003). Wolves: Behavior, Ecology and Conversation. Chicago, IL, University of Chicago Press. Wolves do seem skilled at finding and exploiting vulnerable prey • Innate cues or observational learning?

  43. Mech, L. D. and L. Boitani, Eds. (2003). Wolves: Behavior, Ecology and Conversation. Chicago, IL, University of Chicago Press. Even so, wolves seem to have a low success rate • Being a wolf is a hard business...

  44. Wolves hunt both alone, and in groups. But do they cooperate? • No question that wolves hunt alone and in groups • Breeders and yearlings, and to extent adult female is occupied with pups, it is the adult male and yearlings. • We already saw that pairs (presumably adult pairs) are most efficient. • But do they explicitly cooperate, using Peterson & Ciucci’s definitions • chasing into an ambush • heading off fleeing prey • relay running

  45. Sense that they do cooperate, but little hard evidence • Some evidence that female lions hunt as if they are doing so cooperatively

  46. Alpha dog: leader or center of attention

  47. Pack as family unit suggests a natural order • First of all, it is all about access to resources: food, mate, places & learning the best strategy to get the good and avoid the bad • To the extent that conflict occurs it tends to sort out by age (breeders, yearlings, pups), and within sex (male vs. male, female vs. female) • Packard makes a nice point when she suggests that conflict is in the eye of the observer. Appeasement behaviors elicit muzzle-bite, not other way around... Mech, L. D. and L. Boitani, Eds. (2003). Wolves: Behavior, Ecology and Conversation. Chicago, IL, University of Chicago Press.

  48. Who is following whom? • “In nuclear families, the breeders are the most likely to trot directly and confidently toward a goal, to be solicited by hungry juveniles, and to be followed by family members” - Packard • When traveling in a line, breeding male leads except when they don’t, for example, during breeding season when the female is in front. • In the case of an immigrant step-father, the juveniles were more likely to follow the mother. • In the case of a healthy brother vs. aging father, the juveniles were more likely to follow the brother. • Note the emphasis on following not on leading.

  49. Something to think about? • Fox describes: “The father may also assist the female in keeping cubs away at this time of weaning: he walks over to them and pushes them away and prevents them from following her, and he may give a growl-bark and pin one cub to the ground... he appeared to be instilling discipline and would behave in this way when the cubs were excessively exuberant and were ‘mobbing’ his face. This training continued from approximately ten to twelve weeks, and at the end of the period, the cubs were respectfully submissive toward their parents.” • Is this training to instill “submission”, or is it resource guarding and “stop doing that to me”, the effect of which is that the pups learn that what they were doing was not a good strategy for getting what they wanted. Fox, M. W. (1971). Behaviour of Wolves, Dogs and Related Canids. Malabar, FL, Krieger Publishing Company.

  50. Some notes on coyotes... • Wolves were the natural predator of coyotes so as wolves have disappeared coyotes have flourished. • Prior to the Europeans, coyotes were largely found in plains and southwest, now have expanded to all of North America and Central America • Perhaps more able to tolerate humans? • They appear to pack, with an alpha male & female and related offspring. • In one study, 2/3 of the instances of prey detection were followed by attempts to capture the prey, of which 1/3rd were successful.

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