Geoscience Reference
In-Depth Information
may.overestimate.the.magnitude.of.climate.change.as.a.stressor.or.an.ultimate.driver.
of.extinction..Thoughtful.tracking.of.butterly.demography.and.trends.and.patterns.
of.resource.use.that.speciically.is.designed.to.examine.potential.effects.of.multiple.
drivers.of.faunal.change.is.most.likely.to.yield.strong.inference.
SUMMARY
Activity.patterns.and.vital.rates.of.butterlies.respond.to.both.weather.and.climate..
Responses. to. the. noise. of. weather. confound. the. interpretation. of. responses. to. the.
signal.of.climate.change,.albeit.some.luctuations.in.weather.patterns.are.consistent.
with. projected. effects. of. increases. in. emissions. of. greenhouse. gases.. Moreover,.
ongoing.changes.in.land.use.and.other.stressors.affect.butterlies.both.directly.and.
indirectly..Accordingly,.shifts.in.the.population.dynamics.of.butterlies.cannot.nec-
essarily.be.interpreted.as.responses.to.climate.change..Some.projections.of.effects.
of.climate.change.on.butterlies.have.relected.assumptions.about.the.dependence.of.
butterlies.on.particular.larval.host.plants.or.other.elements.of.habitat..Evidence.sug-
gests.that.in.fact,.many.species.are.relatively.plastic.in.their.resource.requirements..
Two.criteria.must.be.satisied.to.infer.that.changes.in.climate.are.driving.a.change.
in. the. distribution. or. population. dynamics. of. butterlies.. First,. data. on. the. butter-
lies.and.climatic.variables.must.be.available.across.extensive.areas.and.many.years..
Second,.mechanisms.by.which.not.only.climate.but.different.types.of.land.use.may.
affect.individuals.and.populations.must.be.understood..Climate.change.occurs.in.the.
context.of.multiple.existing.and.interacting.stressors..Changes.in.the.quality,.quan-
tity,.and.spatial.and.temporal.diversity.of.resources.resulting.from.land.use.increase.
the.probability.that.short-term.changes.in.weather.and.long-term.changes.in.climate.
will.lead.to.changes.in.the.population.dynamics.of.butterlies.
REFERENCES
Boggs,.C.L.,.and.D.D..Murphy..1997..Community.composition.in.mountain.ecosystems:.cli-
matic.determinants.of.montane.butterly.distributions..
Global Ecology and Biogeography
Letters
.6:39-48.
Boughton,.D.A..1999..Empirical.evidence.for.complex.source-sink.dynamics.with.alternative.
states.in.a.butterly.metapopulation..
Ecology
.80:2727-2739.
Bradley,.B.,.and.E..Fleishman..2008..Relationships.between.expanding.pinyon-juniper.cover.and.
topography.in.the.central.Great.Basin,.Nevada..
Journal of Biogeography
.35:951-964.
Braschler,.B.,.and.J.K..Hill..2007..Role.of.larval.host.plants.in.the.climate-driven.range.expan-
sion.of.the.butterly.
Polygonia c-album
..
Journal of Animal Ecology
.76:415-423.
Crozier,.L..2004..Warmer.winters.drive.butterly.range.expansion.by.increasing.survivorship..
Ecology
.85:231-241.
Davies,.Z.G.,.R.J..Wilson,.S..Coles,.and.C.D..Thomas..2006..Changing.habitat.associations.
of. a. thermally. constrained. species,. the. silver-spotted. skipper. butterly,. in. response. to.
climate.warming..
Journal of Animal Ecology
75:247-256.
Dell,. D.,. T.H.. Sparks,. and. R.L.H.. Dennis.. 2005.. Climate. change. and. the. effect. of. increas-
ing.spring.temperatures.on.emergence.dates.of.the.butterly.
Apatura iris
.(Lepidoptera:.
Nymphalidae)..
European Journal of Entomology
.102:161-167.
Dennis,. R.L.H.. 1993..
Butterflies and climate change
.. Manchester. University. Press,.
United.Kingdom.
