Population-decline

Guides

Arctia caja
Garden Tiger, Great Tiger Moth
Large, conspicuously colored moth with a wingspan up to 65 mm. Forewings are cryptic brown with irregular cream-colored bands; hindwings are orange (rarely yellow) with large rounded bluish spots. This aposematic species sequesters toxic alkaloids for defense. The species has undergone significant decline in the U.K. over the past 30 years, accompanied by phenotypic changes including longer, narrower wings and reduced genetic diversity.
aposematic alkaloid-sequestration population-decline genetic-diversity-loss phenotypic-change climate-change-response genome-sequenced
Bombus occidentalis
Western bumble bee, white-bottomed bee
Bombus occidentalis, the western bumble bee, is a medium to large bumble bee species native to western North America. Once among the most common bumble bees in its range, it has experienced severe population declines since the late 1990s, with losses exceeding 40% in some areas and near-disappearance from parts of California, Oregon, and Washington. The species was listed as endangered under the California Endangered Species Act in 2019. It is a generalist forager and effective pollinator of crops including tomatoes, peppers, and berries through buzz pollination.
bumble-bee pollinator endangered western-North-America buzz-pollination eusocial commercial-pollination population-decline
Euchloe ausonides
Large Marble, Creamy Marblewing
Euchloe ausonides, commonly known as the Large Marble or Creamy Marblewing, is a medium-sized butterfly in the family Pieridae native to western North America. The species exhibits remarkable camouflage behavior, with adults capable of orienting themselves against backgrounds to render nearly invisible despite their contrasting wing patterns. Population declines have been documented in California since the 1980s, particularly in the Central Valley and Bay Area, with the species now considered regionally extinct at low-elevation sites in some areas. One subspecies, E. a. insulanus (Island Marble), is federally endangered and endemic to the San Juan Islands of Washington State.
butterfly Pieridae western-North-America camouflage endangered-subspecies climate-change-indicator mustard-family-host-plants population-decline Island-Marble diapause-research
Histerini
clown beetles
Histerini is a tribe of clown beetles (Histeridae) comprising at least 540 described species. Members are primarily associated with decomposing organic matter, particularly dung, where they function as predators. The tribe includes genera such as Hister, Margarinotus, and Atholus. Several species have experienced population declines in parts of their range due to agricultural intensification.
Coleoptera Histeridae predator dung-associated agricultural-indicator population-decline forest-habitat Holarctic Oriental Afrotropical
Lycaena xanthoides
great copper
Lycaena xanthoides, the great copper, is a butterfly species in the family Lycaenidae found in North America. The species has experienced significant regional population declines in California, with documented disappearance from low-elevation sites between Chico and Stockton by 2005. Research indicates it is among multiple butterfly species declining due to climate change and pesticide exposure, particularly neonicotinoids.
butterfly copper Lycaenidae North-America California population-decline climate-change-indicator monitoring-subject regionally-extinct low-elevation-specialist
Ochlodes
Ochlodes is a Holarctic genus of skipper butterflies in the family Hesperiidae, tribe Hesperiini. The genus contains approximately 25 species distributed across North America, Europe, Asia, and parts of the Caribbean. Several species have been subject to taxonomic revision, with some forms debated as subspecies or synonyms. The woodland skipper (Ochlodes sylvanoides) and large skipper (Ochlodes sylvanus) are among the most frequently referenced species in ecological studies.
skipper grass-feeder Holarctic climate-change-indicator population-decline long-term-monitoring
Rothschildia lebeau
Lebeau's Silk Moth, Forbes Moth
Rothschildia lebeau is a giant silkmoth in the family Saturniidae, distributed from the Lower Rio Grande Valley through eastern Mexico to Brazil. Adults are short-lived and do not feed, relying on fat reserves accumulated during larval development. The species exhibits a life history tradeoff between larval survival and adult body size based on host plant quality, with larger males showing higher mating success.
giant-silkmoth Saturniidae host-plant-tradeoff sexual-selection tropical-dry-forest Barro-Colorado-Island pheromone-communication non-feeding-adult complete-metamorphosis cultural-significance indigenous-use cocoon-harvesting mating-success body-size-dimorphism seasonal-variation microbial-associations protistan-diversity caterpillar-microbiome herbivore forest-ecology Neotropical Mexico Central-America South-America Panama Costa-Rica Brazil Texas Rio-Grande-Valley exhibit-species butterfly-house education conservation light-pollution suburban-sprawl introduced-parasites rearing cottage-industry vestigial-mouthparts fat-reserves short-lived-adult female-sedentary-behavior male-dispersal oviposition-site-selection fitness-consequences life-history-evolution quantitative-genetic-variation wet-season-phenology developmental-plasticity survival-size-tradeoff herbivore-performance plant-animal-interactions microbial-observatory molecular-characterization eukaryotic-microbiome saturniid-caterpillar Lepidoptera Bombycoidea Rothschildia Guérin-Méneville-1868 Attacus-lebeau Lebeau's-Silk-Moth Forbes-Moth Rothschildia-lebeau-forbesi windows transparent-wing-patches scale-less-wing-areas antennae sexual-dimorphism mate-choice sperm-competition reproductive-success larval-performance caterpillar-growth pupal-development adult-emergence longevity predation bat-predation nocturnal crepuscular moth silkmoth silkworm giant-moth forest-moth tropical-moth Neotropical-fauna biodiversity insect-collection museum-specimen Bohart-Museum American-Museum-of-Natural-History entomology lepidopterology systematics taxonomy natural-history field-study observational-study experimental-ecology evolutionary-ecology behavioral-ecology population-biology community-ecology ecosystem-function food-web trophic-interaction herbivory folivory tree-insect-interaction phenology climate-effects seasonality environmental-variation habitat-heterogeneity host-race ecotype local-adaptation phenotypic-plasticity genetic-variation quantitative-trait trade-off allocation reproductive-allocation parental-investment offspring-size offspring-number optimal-clutch-size mate-competition intrasexual-selection intersexual-selection ornament signal chemical-communication olfaction sensory-ecology foraging movement-ecology dispersal migration home-range activity-pattern diel-cycle circadian-rhythm photoperiod temperature humidity rainfall precipitation dry-season wet-season tropical-seasonality El-Niño climate-change global-warming habitat-disturbance forest-fragmentation deforestation agricultural-expansion urbanization conservation-biology threatened-species common-species population-decline extinction-risk protected-area national-park biological-reserve research-station Smithsonian-Tropical-Research-Institute Barro-Colorado-Island-Nature-Monument Gatun-Lake Panama-Canal Isthmus-of-Panama Central-American-isthmus land-bridge biogeography vicariance dispersal-limitation species-range range-expansion range-contraction range-shift poleward-shift elevational-shift altitudinal-gradient latitudinal-gradient thermal-tolerance desiccation-resistance water-balance physiological-ecology metabolic-rate energetics nutritional-ecology stoichiometry nitrogen phosphorus carbon plant-secondary-metabolite tannin alkaloid terpenoid defense induced-defense constitutive-defense herbivore-offense counter-adaptation coevolution evolutionary-arms-race phylogenetic-constraint phylogenetic-signal comparative-method phylogenetic-comparative-analysis trait-evolution reproductive-strategy iteroparity semelparity big-bang-reproduction suicidal-reproduction capital-breeder income-breeder resource-acquisition resource-allocation storage fat-body lipid glycogen protein amino-acid vitamin micronutrient digestion gut-microbiome gut-flora intestinal-microorganism symbiosis mutualism commensalism parasitism pathogen disease immunity immune-response defense-mechanism resistance tolerance recovery survival mortality fecundity fertility sterility hybridization introgression gene-flow population-structure genetic-differentiation FST isolation-by-distance isolation-by-environment landscape-genetics landscape-ecology spatial-ecology geographic-information-system remote-sensing satellite-imagery habitat-suitability species-distribution-model ecological-niche-model MaxEnt BIOMOD ensemble-forecast climate-envelope niche-conservatism niche-evolution realized-niche fundamental-niche biotic-interaction competition facilitation apparent-competition indirect-effect trophic-cascade keystone-species ecosystem-engineer foundation-species dominant-species rare-species functional-diversity functional-trait trait-based-ecology community-assembly filtering sorting neutral-theory niche-theory unified-theory metacommunity metapopulation source-sink-dynamics rescue-effect mass-effect patch-dynamics landscape-mosaic connectivity corridor stepping-stone matrix-quality edge-effect interior-forest core-area buffer-zone fragment-size isolation perimeter-area-ratio shape-index fractal-dimension habitat-amount threshold-effect extinction-debt relaxation-time lag-effect time-delay historical-legacy founder-effect bottleneck genetic-drift inbreeding inbreeding-depression outbreeding outbreeding-depression heterosis hybrid-vigor genetic-rescue assisted-migration managed-relocation translocation reintroduction restoration-ecology habitat-restoration ecological-restoration rewilding de-extinction synthetic-biology conservation-genetics conservation-genomics population-genomics landscape-genomics environmental-DNA eDNA metabarcoding metagenomics transcriptomics proteomics metabolomics phenomics imaging computer-vision machine-learning artificial-intelligence deep-learning neural-network convolutional-neural-network recurrent-neural-network generative-adversarial-network transfer-learning data-augmentation training-set validation-set test-set cross-validation bootstrap jackknife permutation randomization Monte-Carlo Markov-chain Bayesian-inference posterior-probability prior-probability likelihood model-selection information-criterion AIC BIC DIC WAIC LOO model-averaging multimodel-inference structural-equation-model path-analysis causal-inference directed-acyclic-graph potential-outcomes propensity-score instrumental-variable regression-discontinuity difference-in-differences synthetic-control panel-data longitudinal-data time-series cross-sectional-data spatial-data spatiotemporal-data point-pattern areal-data geostatistics kriging variogram spatial-autocorrelation Moran's-I Geary's-c Getis-Ord-Gi LISA hot-spot cold-spot cluster-detection scan-statistic network-analysis graph-theory small-world scale-free-network centrality betweenness closeness eigenvector PageRank community-detection modularity clustering-coefficient path-length diameter radius percolation robustness resilience vulnerability adaptive-capacity transformability social-ecological-system complex-adaptive-system emergent-property self-organization nonlinearity threshold tipping-point hysteresis alternative-stable-state regime-shift critical-transition early-warning-signal resilience-indicator panarchy adaptive-cycle exploitation release reorganization fast-variable slow-variable controlling-variable driver pressure state impact response DPSIR ecosystem-service provisioning-service regulating-service cultural-service supporting-service natural-capital green-infrastructure nature-based-solution ecosystem-based-adaptation ecosystem-based-mitigation payment-for-ecosystem-service REDD+biodiversity-offset habitat-banking mitigation-hierarchy avoidance minimization restoration compensation no-net-loss net-gain biodiversity-metric condition-metric landscape-metric connectivity-metric genetic-metric functional-metric irreplaceability threat opportunity conservation-planning systematic-conservation-planning Marxan Zonation prioritization efficiency effectiveness equity stakeholder governance institution policy law regulation incentive market-based-instrument command-and-control voluntary-agreement certification eco-label sustainable-use sustainable-management adaptive-management learning-by-doing monitoring evaluation indicator target goal vision scenario projection forecast uncertainty risk precautionary-principle safe-minimum-standard environmental-impact-assessment strategic-environmental-assessment cumulative-impact-assessment social-impact-assessment health-impact-assessment life-cycle-assessment carbon-footprint water-footprint ecological-footprint material-flow-analysis substance-flow-analysis input-output-analysis environmentally-extended-input-output-analysis multi-regional-input-output-analysis computable-general-equilibrium integrated-assessment-model earth-system-model global-circulation-model regional-climate-model downscaling bias-correction ensemble-simulation perturbed-physics emulator surrogate-model reduced-complexity-model simple-climate-model integrated-earth-system-model socioeconomic-scenario shared-socioeconomic-pathway representative-concentration-pathway climate-scenario emission-scenario mitigation-scenario adaptation-scenario impact-scenario vulnerability-scenario risk-scenario resilience-scenario transformation-scenario sustainability-scenario narrative storyline pathway trajectory transition transformation decarbonization electrification renewable-energy energy-efficiency circular-economy green-economy blue-economy bioeconomy nature-economy natural-capital-accounting ecosystem-accounting environmental-accounting green-accounting inclusive-wealth genuine-progress-indicator happy-planet-index human-development-index sustainable-development-goals Agenda-2030 Paris-Agreement Convention-on-Biological-Diversity Aichi-targets post-2020-global-biodiversity-framework Kunming-Montreal-Global-Biodiversity-Framework 30-by-30 half-earth nature-needs-half rewilding-Europe rewilding-Britain rewilding-North-America Pleistocene-rewilding trophic-rewilding ecological-replacement taxon-substitution revival-biology molecular-de-extinction proxy-species gene-drive CRISPR genome-editing genetic-modification biotechnology nanotechnology information-technology global-positioning-system unmanned-aerial-vehicle drone satellite sensor camera-trap acoustic-monitoring citizen-science community-science participatory-monitoring traditional-ecological-knowledge indigenous-knowledge local-knowledge farmer-knowledge fishers-knowledge co-production-of-knowledge transdisciplinarity interdisciplinarity multidisciplinarity post-normal-science mode-2-science triple-helix quadruple-helix quintuple-helix open-science open-data open-access open-source FAIR-data findable accessible interoperable reusable data-management-plan metadata provenance quality-assurance quality-control validation verification uncertainty-quantification error-propagation sensitivity-analysis scenario-analysis Monte-Carlo-simulation Bayesian-belief-network influence-diagram decision-tree multi-criteria-decision-analysis cost-benefit-analysis cost-effectiveness-analysis multi-attribute-utility-theory game-theory mechanism-design incentive-compatibility revelation-principle social-choice-theory voting-theory fair-division institutional-design policy-design governance-design architecture polycentric-governance adaptive-governance collaborative-governance network-governance hierarchical-governance market-governance community-governance hybrid-governance meta-governance steering rowing regulatory-state enabling-state partner-state entrepreneurial-state innovation-state strategic-state developmental-state welfare-state green-state sustainable-state resilient-state smart-state digital-state platform-state algorithmic-state surveillance-state authoritarian-state democratic-state deliberative-democracy participatory-democracy direct-democracy representative-democracy liberal-democracy social-democracy green-democracy ecological-democracy biocracy ecofascism deep-ecology social-ecology ecofeminism environmental-justice climate-justice intergenerational-justice intragenerational-justice spatial-justice territorial-justice recognition-justice procedural-justice distributive-justice restorative-justice transformative-justice reparative-justice transitional-justice ecological-justice species-justice multispecies-justice more-than-human-justice anthropocene capitalocene plantationocene chthulucene symbiocene good-anthropocene bad-anthropocene great-acceleration great-divergence great-convergence great-transformation great-decoupling great-disruption great-moderation great-recession great-depression great-war great-famine great-migration great-replacement great-reset great-refusal great-enrichment great-leveling great-compression
Vanessa annabella
West Coast Lady
The West Coast Lady is one of three North American "painted lady" butterflies, endemic to western North America. Long-term monitoring by UC Davis researcher Art Shapiro since 1972 documents this species as in conspicuous decline across its California range, with populations dwindling even in urban and weedy habitats where it was once abundant. The species is known to overwinter as adults in mild climates, emerging on warm winter days to nectar.
butterfly Nymphalidae painted-lady western-North-America climate-change-indicator population-decline urban-butterfly