Lecture 10: Climate-smart protected areas

What are Protected Areas for?

• Convention on Biological Diversity (CBD) protected areas policy mandates ‘30×30’ under the Kunming-Montreal GBF (2022):

  • protect 30% of land and sea by 2030

• Core functions are to safeguard species, habitats and ecological processes from human land-use change

• Current progress towards 30×30:

  • 18.44% land protected globally

  • 10.01% ocean protected globally

  • 24.88% Australia terrestrial PA estate

  • 52% Australia marine PA coverage

• An assumption embedded in the PA design is that the species/habitat you protect today will remain inside the boundary tomorrow

  • climate change violates this assumption as organisms move, phenologies shift, habitats transform

  • the 'fortress conservation' model becomes a cage as conditions deteriorate inside it

Projected changes relevant to PA management

• Temperature:

  • will increase by 2 – 4°C by 2100 even under moderate emissions (SSP2-4.5)

  • extremes intensify faster than means

• Precipitation

  • more intense rainfall events

  • longer droughts, e.g. Mediterranean and SW Australia

• Fire regimes

  • longer fire seasons

  • higher severity

    • e.g. Black Summer (2019–20) burned ~24% of Australia's east-coast temperate broadleaf forests

• Sea-level rise and coastal squeeze

  • affecting low-lying coastal PAs and wetland reserves

• Ocean

  • marine heatwaves

  • bleaching

What is the scale of the problem?

• (Hoffman, Irl & Beierkuhnlein 2019)

  • investigate how climate condition inside the world’s terrestrial PAs will shift by 2070 and which PAs are most exposed

    • analysed 137,432 terrestrial PAs (~14% of

      global land area, 99.9% of total PA area)

    • modelled local-scale climate at 1 km resolution using 19 bioclimatic variables

    • compared current climate (1960–1990) with 2070 projections from 10 GCMs with 2 RCPs (4.5 and 8.5)

    • calculated a 'novel climate index' — proportion of each PA with climate conditions not currently present in that PA

• 41% of PA area expected to gain novel climate conditions by 2070 under RCP 4.5

• 54% over half of every PA on average under RCP 8.5

• The most exposed PAs are:

  • small in area

  • at low elevation

  • low topographic heterogeneity

  • high human pressure (footprint)

  • concentrated in temperate biomes

    • European temperate forests

    • Northern high latitudes

    • Eastern North America

    • Australian temperate Se and SW

The Static-Boundary Problem

• PAs are legal polygons with static boundaries

  • but species and ecosystems shift

• A reserve designed for a species' 1990 range may no longer overlap with its 2060 range

  • climate regime in a PA can change e.g. cool montane may become warm-temperate

• Hannah et al. (2007) showed in Mexico, the Cape Floristic Region and Western Europe that representation targets cannot be met with current PA networks alone under climate change

  • additional areas are required to represent species

How fast must species move?

• (Loarie, Duffy, Hamilton et al. 2009)

  • measure how fast species must move to keep pace with their climate envelope as it shifts across Earth's surface

  • determine which regions allow species to track climate, and which have 'nowhere to go'

    • velocity indxex divides rate of temperature change (°C/year) by local spatial temperature gradient (°C/km)

      • km/year —the speed a species must move to maintain constant temperature

    • based on A1B scenario (high-emissions, now equivalent to RCP 6.0) and 21st-century projections

• 0.42 km/yr global mean velocity

• Average speed Earth's isotherms are moving poleward and upslope

• But velocity varies ~100-fold:

  • in mountains and high-latitude terrain: <0.1 km/yr (species can move upslope locally)

  • flat plains & deserts: >1 km/yr (nowhere to go —must migrate far horizontally)

  • tropical grasslands, mangroves: highest velocities (species escape fastest)

  • tundra: longest climate persistence times (stable habitat longest)

Climate velocity

• Climate velocity is the rate of movement needed to track climate change(km/year)

  • global mean velocity is 0.42 km/year, but highly heterogeneous

• Flat plains have very high velocity (species must travel far to track same temperature)

  • PAs in flat landscapes are most exposed

• Rugged mountains have low velocity

  • most species disperse far too slowly, especially for homogeneous landscapes

• Mountains offer refugia (more time per degree of warming)

• (Dobrowski & Parks 2016)

  • investigate whether climate velocity accurately capture climate change exposure in mountainous regions, and what the implications are for PA networks

    • mapped climate velocity globally using both standard (horizontal) and slope-corrected methods

• In mountainous terrain, organisms must move greater 3D distances than horizontal velocity implies

• Velocity underestimates exposure in mountains by a factor that increases with terrain steepness

  • mountain PAs may not be the safe refugia they appear in standard velocity maps

• Thus, vertical climate velocity should complement horizontal in PA assessment

Species range shifts: patterns and evidence

• Well-documented poleward and upslope shifts across taxa globally since the 1970s

• Birds

  • many Australian passerines and seabirds shifting south

  • tropical species extending into subtropical PAs

• Plants

  • treelines advancing upslope in alpine areas (often lagging climate by decades)

• Insects

  • first records of tropical insects (including disease vectors) in temperate zones

• Marine

  • fish in east Australia shifting poleward

  • tropical species recorded in Tasmanian waters

• Problem for PAs as species that shift out are replaced by species the reserve was not designed for

  • results in loss of ecological integrity even without formal degazettement

Phenological Mismatch

• When the time in annual cycle for when resource demands of the consumer species (i.e. predators, herbivores) are highest does not match the period when its resource (i.e. prey, plants) is most abundant

• Climate warming advances spring phenology at different rates for different species

  • migratory birds may arrive after the insect emergence peak, they evolved to exploit

  • plants flowering before their specialist pollinators emerge resulting in reduced seed set

  • predator-prey cycles disrupted when juvenile prey emerge outside the predator reproductive window

• Inside PAs:

  • these interactions are meant to be protected — but they might disappear

  • even in undisturbed reserves, internal ecological networks can unravel from climate drivers alone

Compounding effects of climate (and other threats)

• Effects inside PAs:

  • edge effects intensify as surrounding matrix degrades

  • feral animals more competitive under drought stress

  • invasive plants exploit post-fire disturbance

  • disease pressure shifts (e.g. chytrid fungus at new temperature ranges)

  • internal fragmentation limits species' movement

• Effects outside PAs (affecting connectivity):

  • agricultural lands provide no movement corridors in extreme heat

  • urban heat island effect blocks dispersal

  • infrastructure (roads, dams) creates hard barriers

  • land tenure fragmentation prevents adaptive landscape-scale management

  • economic pressure on buffer zones increases with climate stress

Marine PAs

• Three-dimensional habitats

• Marine heatwaves cause acute, large-scale mortality events

• Ocean acidification operates globally — no in situ refugia for sensitive calcifiers

• Sea level rise eliminates intertidal habitat from below

  • coastal PAs lose habitat if no active management

• Marine PAs cannot exclude global stressors (heatwaves, acidification) — only local stressors (fishing, pollution, runoff)

  • protection from local stressors does NOT prevent bleaching during heat events (Hughes et al. 2017)

  • thus, MPAs need climate adaptation strategies as a core component (not as a side issue)

The Great Barrier Reef: Australia's Most Iconic MPA

• World Heritage Area (1981) covers 344 400 km² with 2 500 individual reefs

• The zoned MPA:

  • ~33% in 'no-take' green zones since 2004 rezoning

  • houses ~10% of world's fish species

  • 6 marine turtle species

  • 30+ cetacean species

• Recognised as gold-standard MPA management — but climate change is beginning to overwhelm local management

  • first major test case for whether a well-managed MPA can persist under runaway climate change

  • so far MPA status alone cannot prevent bleaching

cause of mass coral bleaching in GBR

• (Hughes et al. 2017)

  • determine if the geographic footprint of mass coral bleaching events on the GBR relate to local water quality, fishing pressure, and MPA zoning during the 2016 marine heatwave

    • aerial surveys of 1,156 reefs along the entire 2,300 km GBR after 2016 heatwave

• 91% of surveyed reefs had bleaching

• 29% suffered severe (>60%) bleaching

  • northern third of GBR most affected, coinciding with peak heat exposure

• No effect of water quality, fishing protection, or zoning on bleaching severity

• Key takeaways:

  • local management cannot prevent marine heatwaves, but it may influence reef recovery

  • mitigation determines whether coral reefs persist globally

  • adaptation determines which reefs persist longest

Implications of the Hughes et al. findings

• Conventional MPA effectiveness metrics (fish biomass, coral cover) are unreliable under climate change

  • implication for ENVM students: MPA design must include climate adaptation management from inception

• GBRMPA Reef 2050 Plan now uses real-time bleaching alerts to prompt intervention

• Heat-tolerant coral genotypes are now a research focus

• Reef restoration is a supplement to (not substitute for) emissions reduction

Marine connectivity under climate change

• Larval dispersal varies enormously with currents climate change alters surface circulation

  • east Australian Current strengthening tropical species reaching Sydney/Tasmania faster

• MPAs designed for current dispersal patterns may be disconnected under future conditions

• Tropicalisation of temperate reef

  • kelp being replaced by tropical algal turf in NSW/SE Australia

• Loss of habitat-forming species (kelp, seagrass) cascades through entire MPA assemblages

  • need for MPAs that span thermal latitudinal gradients to capture species redistributions

Why do external threats matter for PA management?

• Most analyses of climate impacts on PAs focus on what happens INSIDE reserves

• But climate change also reshapes the surroundings, which matters at least as much:

  • shifting fisheries or agriculture

  • renewable energy land demand

  • altered fire regimes

• Each pathway can degrade buffer zones, sever corridors, or directly encroach on PAs

• Climate change is a double whammy: changing biodiversity directly AND changing the human land use pressures around PAs

• PA managers cannot ignore what's happening on adjacent land

Climate-driven shift in viticulture

• (Hannah et al. 2013)

  • determine how climate-driven shifts in viticulture suitability affect biodiversity through land use change

    • modelled global viticulture suitability under RCP 4.5 and 8.5 for 2050

• Major wine regions lose 19–62% (RCP 4.5) or 25-73% (RCP 8.5) of suitable area

• New viticulture suitability emerges in higher latitudes and elevations

  • these new areas overlap with biodiversity hotspots and largely intact mountain ecosystems

• Adaptation responses (irrigation, varietal change) increase freshwater demand in already-stressed Mediterranean regions

Wider patterns of agricultural displacement

• Wine is a tractable case study, but the same logic applies to coffee, cocoa, wheat, grazing etc.

  • coffee

    • arabica suitable area will decline 50%+ by 2050

    • new suitability emerges at higher elevations in Africa/Latin America (often in protected forest)

  • wheat/grain

    • shifting north in Northern Hemisphere

    • in Australia, southward retreat of cropping zones in WA wheatbelt

  • pastoral systems

    • displacement of grazing into rangelands and conservation areas

• Implication of PA expansion planning must use scenarios that include both climate AND climate driven land use change

The energy transition and green dilemma (new pressures on conservation land)

• Conservation argument vs. climate-mitigation argument creates green dilemma

• Decarbonisation requires land-based renewable energy infrastructure

  • solar farms, wind farms, lithium / cobalt mining, biofuel plantations compete with conservation land

• Australia AEMO Integrated System Plan envisages major transmission expansion through bioregions of conservation value

• Bioenergy with carbon capture (BECCS) at IPCC scenarios scales requires land area equivalent to 25–80% of current global cropland

Representation of threatened species by PA system

• (Watson et al. 2011)

  • determine how well Australia's PA system represent threatened species under current conditions, and implications for climate change adaptation

    • assessed overlap between 1,365 threatened species and 89 M ha PA network (11.6% of continent)

• Found ~12% of threatened species occur entirely outside PAs

• ~21% of critically endangered species had no PA representation

• Reptiles and plants are the most poorly represented taxonomic groups

• An efficient 17.8% PA estate could reach representation targets for ALL threatened species

• Key takeaways:

  • Australia's existing PA network is already spatially inefficient

  • climate-smart expansion (toward future suitable habitat) requires building on a foundation that already has serious representation gaps

  • targeted expansion must combine current threatened-species protection AND projected future suitability

Principles of Climate-Smart PA Design

• Acknowledge that 'freeze-frame' conservation is no longer sufficient

• Shift from protecting places to protecting ecological and evolutionary processes

• Design for resilience (capacity to absorb change) AND resistance (buffering against change)

• Retains optionality to avoid irreversible decisions and preserve future management flexibility

• Four core strategies:

  • (1) Representation

  • (2) Connectivity

  • (3) Refugia

  • (4) Adaptive management

• These strategies are not mutually exclusive (best outcomes when integrated)

Representation: cover the full gradient

• Traditional approach

  • protect what is rare or threatened now

• Be climate-smart

  • also protect the full range of environmental variation

• Coarse-filter strategy

  • protecting diverse environments protects diverse future species assemblages

    • elevation gradients are particularly valuable — species can shift upslope within-reserve

    • in flat systems, use geology, soil type, and microclimate variation as surrogates

      • e.g. in Gondwana Rainforests protect multiple rock types and altitude bands

• Systematic conservation planning tools like Marxan, Zonation and incorporate climate projections

Connectivity: let species move

• Connectivity = can landscape facilitate movement between habitat patches

• Climate connectivity = the ability of species to track their climate envelope across space

• Corridor design: wide > narrow; stepping stones where wide corridors impractical; native vegetation preferred

• Connectivity depends on target species —a possum corridor ≠ a microbat corridor

• In Australia: Bush Heritage, Wildlife Land Trust, private land covenants extend connectivity beyond gazetted PAs

• Key challenge: connecting PAs across a matrix of agriculture, urban areas, and infrastructure

Refugia: protect climate shelters

• Refugia are places where local conditions buffer species from climate extremes / change

• Topographic refugia

  • cold air drainage valleys, non-sun-facing slopes, gullies retaining moisture

• Hydrological refugia

  • riparian zones, springs, seeps maintaining cooler, wetter microclimates

• Paleorefugia

  • areas with long continuity of suitable climate

• Microclimate heterogeneity within a reserve provides 'natural insurance' as climate warms

• Management implication:

  • actively identify and protect refugia within and adjacent to PAs

  • in SE Australia wet gullies in sclerophyll forests are refugia for ferns, cool-adapted herps

Climate change refugia for Australian biodiversity

• (Reside et al. 2014)

  • defining characteristics of climate change refugia for Australian biodiversity, and determine how these should be operationalised in conservation planning

• Refugia must:

  • (i) buffer species from climate extremes

  • (ii) sustain population viability and evolutionary processes

  • (iii) minimise negative species interactions

  • (iv) be accessible to species under threat

• Different types of refugia (heat, fire, predation, disease)

• Proposes refugia identification as core component of Australia's PA expansion strategy

• (Game et al. 2011)

  • assessing how climate change adaptation can be incorporated into national-scale systematic conservation planning, using Papua New Guinea as a test case

    • national conservation plan for Papua New Guinea using Marxan

    • integrated climate change refugia (areas of low projected change in 7 climate variables)

    • compared standard biodiversity-only prioritisation vs. climate-aware prioritisation

• Climate-aware planning identified different priority areas —particularly highland refugia

Climate-smart planning today

• Tools: Marxan with Zones, Zonation, prioritizr (R package) — all now support climate inputs

• Inputs typically include current SDMs, future-projected SDMs, climate velocity, refugia surfaces

• Multi-scenario planning:

  • identify areas that are priorities across multiple climate futures (robust solutions)

• Key challenge:

  • SDMs uncertain —ensemble approaches can help

• Outputs are decision-support, not decisions: stakeholder engagement remains essential

Adaptive Management Under Climate Uncertainty

• Traditional management means fixed objectives,
  stable baselines, linear planning cycles

• Adaptive management means updating management
  as new information emerges

• Structured Decision Making: objectives →
  actions → evaluate → update

• Scenario planning across multiple
  plausible futures, identify robust actions
  across all

• Managed relocation (assisted migration) is controversial but may be necessary for highly
  climate-sensitive species

• Triage thinking prioritises species with best
  chance of persistence given limited resources

Australia: particular challenges and opportunities

• Challenges

  • Flat, arid interior — very high climate velocity,
    few topographic refugia
    Highly fragmented agricultural landscape in key biodiversity zones (wheatbelt, rangelands)

  • Island biogeography limits dispersal (SW WA
    effectively isolated)

  • High baseline extinction rates compound
    climate vulnerability

  • Underfunded PA management — ranger
    numbers down significantly since 1990s

  • Feral animals and invasive plants undermine
    resilience before climate even acts

• Opportunities

  • Large, intact landscapes in Cape York, Kimberley,
    Arnhem Land — globally significant refugia

  • Strong Indigenous ranger networks and IPAs —
    67M+ ha under Indigenous stewardship

  • Nature Positive Plan creates new policy levers

  • EPBC Act review — opportunity to embed
    climate into threatened species listing criteria

  • 30×30 target aligns political opportunity with
    conservation need

  • Great Eastern Ranges initiative models
    transjurisdictional cooperation

Indigenous-Led Conservation in a Changing Climate

• Indigenous Protected Areas (IPAs) cover ~50% of
  Australia's National Reserve System area

• Indigenous fire management ('right way fire’), cool
  burning reduces climate-driven mega-fire risk

• Long temporal knowledge horizons

  • many Indigenous knowledge systems track multi-decadal cycles

• Two-eyed seeing by integrating Indigenous and
  Western science frameworks for adaptation

• Indigenous ranger programs provide on-ground
  monitoring capacity unmatched by government
  agencies in remote Australia

• Co-management (e.g. Kakadu, Booderee, Uluru-Kata
  Tjuta) provides governance models

• Climate adaptation funding increasingly directed via
  IPA programs, stewardship history

Monitoring and Early Warnings in Australian PAs