The Cognitive Dog

The Cognitive Dog

Class 3: Wolf and Wild Canid Behavior

Agenda

• Questions from last week

• Plan for next week

• Wolves & coyotes...

Plan for next week

• Perception: readings

• Horowitz, Chapters 2 - 6 (“Umwelt” through “Dog-Eared”)

• Jensen, Chapter 6

• Optional: 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]

• CB: Is knowing wolf behavior useful when training dogs?

Warm-up Questions

• What is communication?

• Does communication imply intent?

• What is intent anyway?

• How would you prove/disprove intent in the case of Scuppers at the backdoor?

• Boitani classified dogs into 3 groups, what were they?

• What is the difference between a pack and a group?

Warm-up Questions

• What term does Boitani use to describe a collection of feral dogs, and why?

• How does he characterize the reproductive success of feral dogs, what accounts for it?

• Would you expect to find long term populations of feral dogs in unpopulated areas?

• What did Feddersen-Petersen have to say about social play in wolves vs. dogs vs. coyotes?

• How does social signaling seem to differ between wolves and dogs, and what is her explanation?

Warm-up Questions

• What is her conclusion regarding the effect of domestication on social interaction in dogs?

• How do her conclusions fit in with Boitani?

• Why don’t people read books on chimpanzee behavior to prepare themselves for raising children?

The economics of being a wolf (wild canid) living in a group

First, 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 Research 15: 1706-1716.

Making a living is hard...

• Wild dogs consume 15.3 MJ of energy per day or roughly the energy provided by 3.5kg of meat...

• sleeping takes up .11MJ/hr and they do this for 21hrs/day

• hunting takes 3.14MJ/hr

• in order to make things balance they must find 4.43MJ/hr of food (1kg of meat)

• If they lose 25% of their kill to hyenas hunting time goes from 3.5 to 12 hr/day just to make things balance. Wild dogs may do best to stay away from niches where hyenas thrive

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.

Wolves are big but coyotes may be the most versatile

weight: 10/12 kglength: .8/.85m

weight: 37/40 kglength: 1.0-1.6m

Being big seems to have implications

• Canids as a group break-down into 2 categories...

• There is a break around 20kg, below this weight the canids feed principally on small prey (< 2kg) whereas at this weight and above the prey tends to be comparable in size or larger than the predator.


So why do some canids live in groups anyway?

• Alternative explanations...

• There are clear benefits to living in groups...

• Hunting, protection and care of young, defense from scavengers

• Marginal benefits but conversely the costs may be low as well...

• Quantity and characteristics of prey make the cost of having other guys around minimal

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

• Example from wolves suggests pair does best, but...


More may be better up to a point


gazelles

wildebeest

large prey

Benefits: strength in numbers...

• Peterson & Ciucci: 1 wolf might lose 2/3 of his moose to scavengers, a pair 1/2, 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.

• Some evidence that pack size increases with prey size, but seems pretty murky

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.

• 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.

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.

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.

• If your food moves around so you have to find it each night, the greater the size of the territory required to make a living.

• But when you find it, its pretty good, so you are set for the day...

• The math is such that a niche that supports a single breeding pair may support a bunch of others without any cost...

• The chances of multiple individuals finding the same food on a given night is low, and even if they do, there is enough for all...

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...

The Synthesis...

• There is some, if small, benefit to living in a pack, but the cost of living in a pack is even smaller, so why not?

• Can we say anything about what a wolf pack looks like?

What is a wolf pack?

alpha wolfsynthetic characters group, MIT Media Lab

Pack size may be loosely tied to prey

size

Note how small they are when feeding on garbage

Mech, L. D. and L. Boitani, Eds. (2003). Wolves: Behavior, Ecology and Conversation. Chicago, IL, University of Chicago Press.

The pack as a nursery...

• Basically packs in the wild are variations on nuclear family, extended family and disrupted family

• Its a 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

Pack is a typically a family : mom, dad, pups and yearlings...

• 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

Alpha: leader or center of attention in what is really a family unit...*

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...


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.

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.

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

Development

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.

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)

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

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.

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%.

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?

Dispersal

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.

Dispersal distances can be quite far

Distance & direction is poorly understood


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

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.

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.


Hunting & do wolves engage in cooperative hunting?

Wolves do seem skilled at finding and exploiting

vulnerable prey

Innate cues or observational learning?


Even so, wolves seem to have a low success

rateBeing a wolf is a hard business...


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

Sense that they do cooperate, but little hard

evidence

Some evidence that female lions hunt as if they are doing so cooperatively

At the end of the evening

• Wolf social behavior is quite complex and not well understood.

• Studies involving wild wolves are exceedingly difficult and are bound to have conflating factors. In captive wolf studies you may be seeing pathological behavior due to the wolves being in an artificial setting.

• Wolves are solving very different problems than are dogs and in a very different ecological niche.

• In my opinion, it is extremely important to cast a critical eye at using explanations of wolf behavior to explain dog behavior.

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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