Wildlife Conservation and Biodiversity
Introduction
Wildlife Conservation Society Canada (WCS Canada) involves comprehensive research, advocacy, and outreach efforts aimed at preserving wildlife and their habitats for future generations.
Justina, the speaker, has extensive experience working at both species and population levels, combined with engagement in policy development related to wildlife management and comprehensive conservation strategies that address ecological integrity and sustainability.
Justina's Background
Justina's PhD research, conducted in Central Africa, focused on the elusive forest mongoose, a species previously unstudied in that region, contributing significantly to the understanding of its behavior, ecological role, and conservation needs.
She has undertaken extensive fieldwork on various carnivores, including leopards and golden cats, in remote habitats, employing advanced tracking methods such as radio collars and GPS technology to monitor animal movements, behavioral patterns, and establish conservation needs effectively.
After relocating to Canada, her research focus has shifted towards northern species like wolverines and caribou, highlighting the unique and complex conservation challenges these species face in changing climates, including habitat fragmentation, climate change, and human encroachment.
WCS Canada Overview
The Wildlife Conservation Society Canada employs approximately 70 dedicated scientists and has been operational for over 20 years; it started with only a small team passionate about wildlife conservation advocacy.
The organization emphasizes long-term, field-based research conducted in specific locations throughout Canada, enabling targeted and effective conservation strategies that are adaptable to local ecological contexts.
Key initiatives undertaken by WCS Canada include training the next generation of conservation scientists, fostering academic partnerships, conducting climate change research focusing on peatland ecosystems, and influencing biodiversity policy at both national and international levels.
Importance of Biodiversity
Biodiversity represents the variety and variability of life forms on Earth, often equated with "nature" and is critical for maintaining ecological balance and promoting ecosystem resilience.
It can be measured and assessed at multiple levels: genetic diversity within species, species diversity (the number of different species), community diversity (the variety of species in a specific area), ecosystem diversity (different ecosystems in a region), biome diversity (different biomes on the planet), and biosphere scale (the global sum of all ecosystems).
Biodiversity is vital as it underpins essential ecosystem services, such as pollination, nutrient cycling, water purification, and soil fertility, all of which contribute significantly to the overall health, stability, and resilience of the planet's environments.
Global and Canadian Biodiversity Status
Global biodiversity is currently in a state of significant decline, primarily due to mounting threats, including habitat destruction from urbanization and agriculture, pollution, invasive species, overexploitation of resources, and the overarching impacts of climate change, which are leading to altered habitats and species extinctions.
In Canada, the deterioration of biodiversity mirrors global trends, predominantly driven by urbanization, agricultural intensification, and the resulting loss of natural habitats essential for flora and fauna survival.
This decline calls for urgent, coordinated conservation actions to mitigate negative impacts on flora and fauna and to promote ecosystem recovery on both local and global scales.
Measuring and Addressing Biodiversity
In Canada, biodiversity measurement involves intricate monitoring systems that assess various indices of health and diversity across different ecosystems, species populations, and genetic variability through innovative technologies such as remote sensing, field surveys, and citizen science.
Collaboration among scientists, policymakers, conservation organizations, and local communities is crucial in implementing effective strategies to conserve biodiversity, which includes habitat restoration projects, species protection efforts, sustainable land-use practices, and community-led conservation initiatives that empower local populations to engage in wildlife management and conservation activities.
I. Why Do Small Populations Matter?
Note: Additional Insights from WILD3810 Lecture 4
According to population ecology research such as that from Rushing Lab’s WILD3810 Lecture 4, population dynamics are heavily influenced by two primary types of stochasticity:
Environmental Stochasticity:
Refers to random fluctuations in environmental conditions that affect demographic parameters (like birth or death rates).
Examples include droughts, fires, harsh winters, disease outbreaks, and changes in food availability.
These fluctuations are usually external to the population and can impact all individuals regardless of population size.
Particularly significant because even large populations may be affected, but small populations are less buffered and may be pushed toward extinction.
Demographic Stochasticity:
Refers to random variation in the fate of individuals (e.g., survival and reproduction), which can lead to variability in growth rates among small populations.
Even with stable average birth and death rates, chance events at the individual level (e.g., a high proportion of females failing to reproduce) can skew outcomes.
This kind of stochasticity is especially impactful when populations are small because each individual's contribution to the next generation is proportionally greater.
These concepts underscore the importance of accounting for stochasticity when modeling and managing small populations. Simple deterministic models that assume constant birth and death rates may vastly underestimate extinction risk.
Small populations are more vulnerable to extinction due to several factors:
Demographic stochasticity – Random fluctuations in birth and death rates. These chance events can disproportionately impact small populations.
Example: Coin flip model – With only 3 individuals, a series of bad coin flips (e.g., all die) results in extinction.
Environmental stochasticity – Random environmental changes that affect all individuals.
Biotic examples: Changes in food availability, disease outbreaks.
Abiotic examples: Storms, droughts, temperature shifts.
Loss of genetic diversity – Reduces a population's ability to adapt to environmental change and survive long-term.
Increases inbreeding and expression of deleterious alleles.
II. Allee Effect
Definition: A positive correlation between individual fitness and population size or density.
Implication: When populations are too small, individuals may not find mates or may be more vulnerable to predation, leading to a downward spiral.
III. Genetic Drift and Its Effects
Genetic Drift – Random changes in allele frequency due to chance, not selection.
Happens in all populations but strongest in small ones.
Key consequences:
Increases genetic variation among populations.
Decreases genetic diversity within populations.
Affects alleles at all loci simultaneously.
Founder Effect: A few individuals start a new population; their genetic makeup is not representative of the original population.
Population Bottleneck: A population is drastically reduced in size; surviving individuals repopulate with reduced genetic diversity.
IV. Counteracting Genetic Drift
Mutation: Introduces new alleles but mutation rates are too low to compensate for genetic drift in small populations.
Migration (gene flow): Movement of individuals between populations can introduce genetic diversity and offset the effects of drift.
V. Consequences of Reduced Genetic Diversity
Loss of evolutionary flexibility – Inability to adapt to environmental change. Organisms must:
Move
Acclimate
Adapt
Die
Inbreeding depression – Occurs when related individuals mate and produce offspring with reduced fitness due to homozygosity for deleterious alleles.
Higher offspring mortality
Lower reproductive success
Sterility or weakness
Outbreeding depression – Crosses between genetically distant individuals or species reduce fitness.
Example: Ligers (lion+tiger), mules (horse+donkey)
Usually rare, and sometimes hybrid vigor (heterosis) can occur instead.
VI. Effective Population Size (Ne)
Definition: The size of an idealized population that would experience the same genetic drift as the actual population.
Always smaller than actual population size (N).
Formula:
Where:
Nm = number of breeding males
Nf = number of breeding females
Factors that decrease Ne:
Unequal sex ratio (e.g., 5 males and 704 females in a population of 1166 elephants)
Variation in reproductive success – Some individuals produce many more offspring than others.
Population size fluctuations and bottlenecks
VII. Extinction Vortex
Feedback loop where small populations suffer from reduced fitness, genetic diversity, and adaptability, leading to further decline.
Can be triggered by any factor but is often compounded by multiple interacting effects.
VIII. Minimum Viable Population (MVP)
Definition (Shaffer, 1981):
"The smallest isolated population having a 99% chance of remaining extant for 1,000 years despite demographic, environmental, and genetic stochasticity, and natural catastrophes."
MVP estimates vary widely by species.
Median MVP: ~4000 individuals (from over 200 species)
Species with high variability (e.g., invertebrates): MVP ~10,000
Minimum Dynamic Area (MDA) – The amount of habitat needed to support the MVP.
IX. Population Viability Analysis (PVA)
Purpose: Project population trends and extinction risk using models.
Inputs required:
Current population size (censusing, tagging, long-term data)
Demographic rates (birth, death, immigration, emigration)
Key Equation:
(Where Nt is population size at time t)
Or using geometric growth:
Where:
R = birth rate - death rate
Example:
Population of 100 tigers
50 births, 10 deaths
R = 0.4;
X. Conservation Strategies
In Situ Conservation – On-site, in the species' natural habitat
Maintains ecosystem processes
Preserves natural behaviors
Ex Situ Conservation – Off-site (zoos, seed banks, aquaria)
Captive breeding
Useful for species with no remaining wild habitat
Can lead to reintroduction or reinforcement programs
Reintroduction – Restoring a species to a place it historically inhabited
Reinforcement – Adding individuals to boost an existing population
Introduction – Placing species in a new, suitable habitat
Soft Release – Animals are gradually acclimatized to the wild
Hard Release – Immediate release with no acclimation
XI. Examples of Conservation Programs
California Condor (Gymnogyps californianus):
One of the most iconic cases of ex situ conservation.
In 1987, only 22 individuals remained; all were captured for a captive breeding program.
Intensive management included health checks, artificial incubation, and puppet-rearing to avoid human imprinting.
First wild release occurred in 1992. As of recent estimates, over 300 condors are in the wild, with additional individuals in captivity.
Major challenges: lead poisoning from ingested bullet fragments, power line collisions, low reproductive rate.
Golden Lion Tamarin (Leontopithecus rosalia):
Small primate native to Brazil's Atlantic Forest, endangered due to habitat loss and fragmentation.
Population dropped to ~200 in the wild by the 1980s.
Captive breeding programs, habitat restoration, and translocation efforts brought the wild population to ~3700 by the 2020s.
Programs included reintroduction of zoo-born individuals and construction of habitat corridors.
Kakapo (Strigops habroptilus):
Critically endangered, flightless parrot from New Zealand.
Entire population relocated to predator-free islands.
Managed breeding using artificial insemination and supplemental feeding.
Individual birds are named and closely tracked; in 2023 the population reached over 250.
Whooping Crane (Grus americana):
North America’s tallest bird; reduced to 15 individuals in the 1940s.
Recovered via captive breeding, migration training (e.g., using ultralight aircraft), and habitat protection.
Several populations now exist, including the non-migratory Florida population and the migratory Wisconsin-to-Florida group.
Threats include habitat loss, collisions with power lines, and predation on chicks.
These programs illustrate the importance of long-term planning, human intervention, and collaboration across disciplines in bringing species back from the brink of extinction.
XII. Protected Areas (PAs)
Goal: 30x30 – Protect 30% of land and sea by 2030
Can be inhabited or uninhabited
Focuses: biodiversity, ecosystem services, culture
SLOSS Debate – Is it better to have a Single Large Or Several Small reserves?
Depends on species, habitat needs, threats
Frodo Effect – Small natural features can be key to biodiversity
Habitat Connectivity – Vital for gene flow and species movement
Corridors, underpasses, overpasses
Example: Banff Park reduced roadkill by 96%
XIII. Conservation Beyond Protected Areas
Over 70% of Earth remains unprotected
Many species live outside PAs
Strategies:
Co-management with local/Indigenous peoples
Integrated Conservation and Development Projects (ICDPs) – Blend conservation and human needs
Payments for Ecosystem Services (PES):
Compensation/insurance (e.g., for predator losses)
Revenue-sharing (community-based wildlife management)
Conservation incentives (Sweden's wolverine program)
XIV. Urban Conservation and De-extinction
Reconciliation Ecology – Restoring biodiversity in cities and human-dominated landscapes
De-extinction Techniques:
Back-breeding – Selective breeding for ancestral traits
Cloning – e.g., 2003 ibex clone (died after 10 mins)
Genetic Engineering – Editing genomes to recreate extinct species
Ethical Concerns:
Should we bring extinct species back?
Do they have a place in today’s ecosystems?
Will they survive in the wild or remain in captivity?
The Frodo Effect is a conservation biology concept emphasizing that small natural features can have a disproportionately large impact on biodiversity—similar to how the small and seemingly insignificant Frodo in The Lord of the Rings plays a massive role in the fate of Middle-earth.
Here's an in-depth explanation:
🌿 What is the Frodo Effect?
Named metaphorically after Frodo Baggins, this concept argues that not all biodiversity value lies in large, charismatic landscapes.
Tiny habitats, like ephemeral wetlands, boulder fields, hollow logs, or cliff faces, might:
Host rare or endemic species
Provide key resources like water, shelter, or breeding sites
Act as critical stepping stones or genetic exchange points in fragmented ecosystems
🧠 Why it matters:
Conservation efforts tend to focus on large, iconic reserves.
But overlooking small, ecologically rich spaces can lead to the loss of unique biodiversity.
Incorporating the Frodo Effect into landscape planning ensures small-scale biodiversity hotspots are protected.
🛠 Example Applications:
Protecting small limestone outcrops that host rare plant species
Maintaining tree hollows critical for nesting birds and bats