Evidence map›Paper›PMID 33431566›Full record

ReviewProceedings of the National Academy of Sciences of the United States of America2021

The decline of butterflies in Europe: Problems, significance, and possible solutions.

Martin S Warren, Dirk Maes, Chris A M van Swaay, Philippe Goffart, Hans Van Dyck, Nigel A D Bourn, Irma Wynhoff, Dan Hoare, Sam Ellis

Abstract readReview
In one paragraph

Review in Proceedings of the National Academy of Sciences of the United States of America, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 80 papers.

0numbers the graph read from it
0cells of the map it votes in
80citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

80 citing papers in PubMed.

  1. West European Hedgehog (Ecology and evolution · 2026
    Article
  2. Biases in butterfly survey effort and patterns of protocol used across biogeographic regions.Ecological applications : a publication of the Ecological Society of America · 2026
    Review
  3. Microclimate-based oviposition site selection in butterflies and moths.Biological reviews of the Cambridge Philosophical Society · 2026
    Review
  4. Article
  5. Article
  6. Habitat Use Across the Geographic Range ofEcology and evolution · 2026
    Article
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20 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Martin S WarrenButterfly Conservation Europe, East Lulworth, Dorset BH20 5QP, United Kingdom; martin.warren@bc-europe.eu.
Dirk MaesSpecies Diversity Group, Research Institute for Nature and Forest, B-1000 Brussels, Belgium.ORCID 0000-0002-7947-3788
Chris A M van SwaayDutch Butterfly Conservation, NL-6700 AM Wageningen, the Netherlands.
Philippe GoffartDépartement d'Etude du Milieu Naturel et Agricole, Service Public de Wallonie, B-5030 Gembloux, Belgium.ORCID 0000-0002-5495-3355
Hans Van DyckBehavioural Ecology and Conservation Group, Biodiversity Research Centre, Earth and Life Institute, Université Catholique de Louvain (UCLouvain), B-1348 Louvain-la-Neuve, Belgium.ORCID 0000-0002-2013-6824
Nigel A D BournButterfly Conservation, East Lulworth, Dorset BH20 5QP, United Kingdom.ORCID 0000-0003-1416-6047
Irma WynhoffDutch Butterfly Conservation, NL-6700 AM Wageningen, the Netherlands.ORCID 0000-0002-3003-897X
Dan HoareButterfly Conservation, East Lulworth, Dorset BH20 5QP, United Kingdom.
Sam EllisButterfly Conservation, East Lulworth, Dorset BH20 5QP, United Kingdom.ORCID 0000-0001-6081-045X

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

We review changes in the status of butterflies in Europe, focusing on long-running population data available for the United Kingdom, the Netherlands, and Belgium, based on standardized monitoring transects. In the United Kingdom, 8% of resident species have become extinct, and since 1976 overall numbers declined by around 50%. In the Netherlands, 20% of species have become extinct, and since 1990 overall numbers in the country declined by 50%. Distribution trends showed that butterfly distributions began decreasing long ago, and between 1890 and 1940, distributions declined by 80%. In Flanders (Belgium), 20 butterflies have become extinct (29%), and between 1992 and 2007 overall numbers declined by around 30%. A European Grassland Butterfly Indicator from 16 European countries shows there has been a 39% decline of grassland butterflies since 1990. The 2010 Red List of European butterflies listed 38 of the 482 European species (8%) as threatened and 44 species (10%) as near threatened (note that 47 species were not assessed). A country level analysis indicates that the average Red List rating is highest in central and mid-Western Europe and lowest in the far north of Europe and around the Mediterranean. The causes of the decline of butterflies are thought to be similar in most countries, mainly habitat loss and degradation and chemical pollution. Climate change is allowing many species to spread northward while bringing new threats to susceptible species. We describe examples of possible conservation solutions and a summary of policy changes needed to conserve butterflies and other insects.

Indexed as

ButterfliesConservation of Natural ResourcesExtinction, BiologicalAnimalsBiodiversityEuropebutterfliesconservationEuropeinsect declinemonitoring

Identifiers

PMID33431566
PMCPMC7812787

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.