title: Advantages of volunteer-based biodiversity monitoring in Europe.
abstract: Without robust and unbiased systems for monitoring, changes in natural systems will remain enigmatic for policy makers, leaving them without a clear idea of the consequences of any environmental policies they might adopt. Generally, biodiversity-monitoring activities are not integrated or evaluated across any large geographic region. The EuMon project conducted the first large-scale evaluation of monitoring practices in Europe through an on-line questionnaire and is reporting on the results of this survey. In September 2007 the EuMon project had documented 395 monitoring schemes for species, which represents a total annual cost of about 4 million euro, involving more than 46,000 persons devoting over 148,000 person-days/year to biodiversity-monitoring activities. Here we focused on the analysis of variations of monitoring practices across a set of taxonomic groups (birds, amphibians and reptiles, mammals, butterflies, plants, and other insects) and across 5 European countries (France, Germany, Hungary, Lithuania, and Poland). Our results suggest that the overall sampling effort of a scheme is linked with the proportion of volunteers involved in that scheme. Because precision is a function of the number of monitored sites and the number of sites is maximized by volunteer involvement, our results do not support the common belief that volunteer-based schemes are too noisy to be informative. Just the opposite, we believe volunteer-based schemes provide relatively reliable data, with state-of-the-art survey designs or data-analysis methods, and consequently can yield unbiased results. Quality of data collected by volunteers is more likely determined by survey design, analytical methodology, and communication skills within the schemes rather than by volunteer involvement per se.
authors.affiliation: Station d'Ecologie Expérimentale du CNRS à Moulis, 09200 Saint Girons, France. ds@die-schmellers.de
authors.forename: Dirk S
authors.initials: DS
authors.lastname: Schmeller
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Henry
authors.forename: Romain
authors.initials: R
authors.lastname: Julliard
authors.forename: Bernd
authors.initials: B
authors.lastname: Gruber
authors.forename: Jean
authors.initials: J
authors.lastname: Clobert
authors.forename: Frank
authors.initials: F
authors.lastname: Dziock
authors.forename: Szabolcs
authors.initials: S
authors.lastname: Lengyel
authors.forename: Piotr
authors.initials: P
authors.lastname: Nowicki
authors.forename: Eszter
authors.initials: E
authors.lastname: Déri
authors.forename: Eduardas
authors.initials: E
authors.lastname: Budrys
authors.forename: Tiiu
authors.initials: T
authors.lastname: Kull
authors.forename: Kadri
authors.initials: K
authors.lastname: Tali
authors.forename: Bianca
authors.initials: B
authors.lastname: Bauch
authors.forename: Josef
authors.initials: J
authors.lastname: Settele
authors.forename: Chris
authors.initials: C
authors.lastname: Van Swaay
authors.forename: Andrej
authors.initials: A
authors.lastname: Kobler
authors.forename: Valerija
authors.initials: V
authors.lastname: Babij
authors.forename: Eva
authors.initials: E
authors.lastname: Papastergiadou
authors.forename: Klaus
authors.initials: K
authors.lastname: Henle
mesh_terms: D000818:Animals; D044822:Biodiversity; D003247:Conservation of Natural Resources / Q000191:economics*; D004784:Environmental Monitoring / Q000191:economics* / Q000379:methods*; D005060:Europe; D007391:International Cooperation; D010944:Plants; D014838:Volunteers