Lecture 35 - Behavioural Ecology in Conservation

AVBS3004: Behavioural Ecology in Conservation

Learning Outcomes

• Understand the theory and practice of behavioural science in conservation.
• Link behaviour as a conservation goal, in its own right, to management.
• Use behaviour as a predictive tool and understand behavioural constraints as a conservation problem.

Animal Behaviour – A Recap

• Definition: Everything animals do, including movement, other activities, and underlying mental processes (Britannica).
• Includes:
  • Individual behaviour
  • Intraspecific interactions
  • Interspecific interactions

Behaviour as a Conservation Goal

• Conserving specific behaviours of wildlife might be the primary conservation goal.
• Examples:
  • Unusual or unique mating systems
  • Spectacular migrations
  • Communication
  • Animal cultures

Behaviour as an Ecological Indicator

• Conservation problems are essentially population-level issues.
• Collecting population-level information (population size, survival rates, etc.) is difficult and costly.
• Behaviour can help provide indicators.

Elephant Population

• Adult elephants killed by humans vs. elephants, showing changes after park fencing.
• Before fencing:
  • Males: 5 by humans, 0 by elephants
  • Females: 6 by humans, 0 by elephants
• After fencing:
  • Males: 1 by humans, 14 by elephants
  • Females: 1 by humans, 1 by elephants
• Source: Whitehouse, A.M. & Kerley, G.I.H. (2002) Oryx, 32, 243-248.

Behaviour as Ecological Indicators

• Orca behavioural indicators for marine protected area (MPA) selection.
• Numbers of whale-watching vessels approximate the population size of Vancouver Island orcas.
• Individuals were most vulnerable to disturbance while feeding.
• Led to a focus on protecting feeding grounds from boats.
• Ashe et al. 2010 Anim. Cons. 13: 196-203

Orca Behavioural Typology to Define Feeding Grounds

• Observations and corresponding behaviours:
  • Rest: Slow with predictable coordinated short dives.
  • Travel: Consistent group heading with long independent dives.
  • Social: Tight-knit groups with irregular dives and breaching etc.
  • Feed: Group spread out, no consistent heading, long independent dives.

Tinbergen's Framework

• Proximate Level (Individual Level):
  • Cause (Drivers)
    • Mechanism
    • Ontogeny (Development)
• Ultimate Level (Evolutionary Level):
  • Function
    • Origin
    • Phylogeny
• Constraints
• Predictive Tools

Tinbergen’s Framework Explained

• Mechanism (Causation): Immediate triggers like hormones, neural circuits, and sensory inputs.
• Development (Ontogeny): How behaviour develops over an animal’s lifetime; influence of genetics and experience.
• Function (Adaptive value): Survival or reproductive advantage of the behaviour; how it increases fitness.
• Evolution (Phylogeny): How the behaviour evolved over time in the species’ lineage; evolutionary history.

Tinbergen’s Framework in a Conservation Context – Cetacean By-Catch

• Buchholz, R. (2007) Trends in Ecology & Evolution, 22, 401-407.

Behavioural Mechanisms

• Songbirds and traffic:
  • Generally reduced abundance near roads.
  • Reasons: collision, pollution, less food, visual disturbance, noise.
• Studies:
  • Reijnen, R. & Foppen, R. (1994) J. of Applied Ecol., 31, 85-94.
  • Rheindt, F.E. (2003) J. für Ornithologie, 144, 295-306.
  • Halfwerk et al. (2011) J. Applied Ecol., 48, 210-219
• Illustration of differences in song frequency of birds.

Mechanisms: Captive Breeding

• Sexual selection and captive breeding of giant pandas:
  • Notoriously difficult to breed.
  • Traditionally assumed males were the choosy sex.
  • Behavioural observation indicated mating occurs only where both sides of a pair show high levels of courting.
  • Peng et al. 2009. Belg. J Zoology 139: 87-92

Behavioural Ontogeny

• Captive rearing and release of whooping cranes:
  • Down to around 20-30 individuals in the 1940s.
  • Protection introduced but slow recovery.
  • New population deemed necessary, leading to reintroduction program.

Behavioural Ontogeny: Attempts

• First attempt (1970s):
  • Cross-fostered with sandhill cranes.
  • Migration established but no breeding.
• Second attempt:
  • Hand-rearing.
  • Migration not established; population not viable.
• Third attempt:
  • Hand-rearing with puppets.
  • Predator aversion training.
  • Trained to follow microlite to establish migration.
  • Successful population establishment due to:
    • Avoiding inappropriate imprinting
    • Learning on non-innate behaviours
    • Maintenance of social structure

Function - Behavioural Science as a Conservation Tool

• Interest areas don't apparently overlap, but are linked in principle:
  Genes Individuals Populations Species Communities

Ultimate Function (Behavioural Ecology)

• Understanding behaviour from an evolutionary perspective:
  • Key principle: individuals behave so as to maximise their own fitness, not for the benefit of the population or species.
  • e.g., swallow’s tails resulting from sexual selection – increased individual fitness but reduced overall survival.
    Long-forked tail streamers preferred by females, but longer tails inhibit survival by slowing flight.
    Tail trait evolved to give individual males a reproductive edge, even if it makes them (or population) more vulnerable.

Conservation-Related Examples

• Kakapo sex ratio problems with supplementary feeding:
  • Critically endangered conservation programs (many using supplementary feeding) females producing more male offspring (potential to produce more offspring and pass on genes) more males in population reduced population growth overall.
• Infanticide in brown bears:
  • Male bears kill cubs they don’t sire (limits competitor males passing on genes and females re-enter oestrus cycle) increase in individual reproductive success.
  • Loss of cubs reduces juvenile survival rate and damages population growth.
  • Human disturbance impacting bear movements can influence this behaviour.

Allee Effects and Behaviour

• Individual fitness decreases as population density or size drops.
• Being rare or small population is bad for survival.
• Includes:
  • Difficulty finding mates
  • Breakdown of social behaviours
  • Loss of learned or cultural behaviours
  • Reduced mate choice

Allee Effect Mechanisms in Wild Dog Packs

• Foraging – defence and efficiency
• Breeding – pup care and defence
• Survival – defence and food sharing
• Courchamp, F. & Macdonald, D.W. (2001) Anim Cons, 4, 169-174.

Allee Effect Mechanisms in Vancouver Island Marmots

• Population decline and “social meltdown”
• Brashares et al (2010) J. Anim. Ecol. 79: 965-973

Phylogenetic Patterns

• Can behaviour help explain variation in extinction risk between species?
• Some evidence that more strongly sexually-selected species (most birds) are more prone to extinction (Doherty et al. 2003).
• Obvious changes in vulnerability based on behaviours as environments change (particularly with increased human impacts).

Broader Phylogenetic Patterns: Behavioural Trait Linked to Extinction Risk

• Strong sexual selection:
  • Yes
  • Birds with elaborate courtship displays (such as peacocks)
• Specialized foraging or habitat use:
  • Yes
  • Koala, panda
• Complex social systems:
  • Sometimes
  • African wild dogs, elephants
• Migration or large home ranges:
  • Yes
  • Monarch butterflies, caribou, raptors
• Low behavioural flexibility:
  • Yes
  • Many island birds, corals

Behavioural Constraints as Conservation Problems

• Some behaviours are maladaptive under new or human-altered conditions (even if they evolved adaptively).
  • Mate-finding failure
  • Fixed migration patterns (populations can’t adjust under human pressures and/or climate shifts)
  • Anti-predator behaviours not suited to introduced predators (Australian invasives and CWR mammals)
  • Inflexible diets so can’t adjust to shifting habitats
  • Protected areas aren’t always designated around animal behaviours

Integrating Behaviour into Conservation Planning

• Using behavioural ecology is key to inform protected area size and design.
• Monitoring wildlife behaviour as a conservation indicator (e.g. vigilance, stress, courtship, etc.).
• Managing and maintaining key behaviours (e.g. migration routes).
• Cultural conservation: preserving learned traditions and social structures.

Things to Think About

• Linking our understanding of animal behaviour to translocations and reintroductions.
• Can we modify the environment or management strategy to support key behaviours?
• Ethical considerations of influencing animal behaviours.
• Should we put more effort into conserving behaviours or should species evolve to adapt to a changing world?